Assessment of Pesticide Contamination Level of Fish and Human Health Risks in Lake Ziway, Ethiopia

Assessment of Pesticide Contamination Level of Fish and Human Health Risks in Lake Ziway, Ethiopia | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Assessment of Pesticide Contamination Level of Fish and Human Health Risks in Lake Ziway, Ethiopia Mekonnen Maschal Tarekegn, Dagnachew Lelisa Duga, Yitayal Addis Alemayehu, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6016451/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Lake Ziway, located in the Ethiopian Rift Valley, faces significant environmental pressure due to intensive agricultural and floriculture practices. Pesticides are heavily utilized to boost production. This study examined the concentrations, bioaccumulation, and health risks associated with 22 selected pesticides in four fish species: Oreochromis niloticus, Cyprinus carpio, Carassius carrasius , and Clarias gariepinus . A total of 48 fish, grouped by size into three sets for each species, were sourced from local fisheries and analyzed in duplicate. The dorsal muscle samples were extracted using a speed extractor, purified with florisil, and quantified using gas chromatography coupled with mass spectrometry (GC-MS/MS). Most compounds showed mean recoveries between 60% and 120%, except for dieldrin (51.33%) and bendiocarb (121.86%). Detection limits ranged from 0.01 to 2.6 µg kg − 1 . Positive pesticide residues, including Σ HCH, Σ DDTs, HCB, Σ heptachlor, chlorpyrifos, propoxur, and diazinon, were detected at concentrations between 0.010 and 66.44 µg kg − 1 . However, levels of β-HCH, γ-HCH, aldrin, dieldrin, endosulfan I, endosulfan sulfate, bendiocarb, profenofos, chlordane-trans, chlordane-cis, methoxychlor, and chlorpyrifos-methyl were below the detection limit. DDTs were the most prevalent contaminants, with concentrations ranging from 5.08 to 213.61 µg kg − 1 , likely due to historical contamination from past practice. Prolonged consumption of pesticide-contaminated fish poses carcinogenic risks, highlighting the need for stringent enforcement of pesticide regulations. bioaccumulation concentration fish health risks pesticides Figures Figure 1 Figure 2 Figure 3 Figure 4 Introduction Anthropogenic activities, including the heavy use of agrochemicals, unsustainable land use, and municipal and industrial waste discharge, increasingly impact the quality of natural water bodies in many developing countries. Ethiopia, according to Awulachew et al. ( 2007 ), is one of the African nations with the most significant water resources, including 275 km² of smaller water bodies, 7185 km of rivers, and major lakes and reservoirs with an estimated surface area of 7334 km² (Kebede et al., 2017). Lake Ziway, the second most important fishing hub in the country, is home to fifteen different fish species (Daniel, 2015). For generations, people living along Lake Ziway's shoreline have depended on its fishery for food and income, as it is a readily accessible and vital source of livelihood. Spliethoff et al. ( 2009 ) estimate the potential yield from all the species in the lake to be between 2,500 and 6,680 tons per year. Additionally, the lake provides water to large-scale investors in horticulture and floriculture, as well as smallholder farmers. For the town of Ziway, the lake is a crucial source of drinking water and irrigation. Due to its freshness and low salinity, this water resource is highly valued by several sectors (Spliethoff et al., 2009 ). However, in addition to the municipal waste discharges from Ziway, the past two decades have seen rapid growth in smallholder and large-scale export-oriented vegetable, fruit, and commercial floriculture farms along the shoreline, tributary rivers, and outflow river of Lake Ziway (Jansen et al., 2007). The extensive use of agrochemicals in these farms causes pollution. These chemicals are applied to boost agricultural productivity and control disease vectors, thereby ensuring food security (Mergia et al., 2021 ). However, when pesticides are used improperly, they pose risks to wildlife, the environment, and human health (Tibebe et al., 2022 ). Pesticide residues from these farms may contaminate Lake Ziway and its fish species through various mechanisms, including runoff, drainage, and airborne deposition during application (Teklu et al., 2018 ). Chemicals sequestered in the soil can be released into the lake via runoff and erosion from the surrounding catchment, where they may enter to the food chain and affect fish populations (Jansen & Harmsen, 2011 ). This poses a significant threat to the quantity and quality of fish species, which are essential for commerce, a key ecosystem service provided by Lake Ziway. Abera et al. (2018) estimated that the lake's annual fish supply has decreased by about 33%, from 3180 tons recorded by LFDP in 1997 to 1,157 tons, along with a shift in the species composition. In 1994, Carpio and O. niloticus contributed 0.12% and 89% respectively to the fish catch, while by 2014, C. carpio's share had increased to 28% and O. niloticus' had dropped to 50% (Abera et al., 2018). Fish contaminated with pesticides may absorb harmful chemicals, which can then enter the human food chain. Fish contain high proteins and vitamins that are considered a healthier dietary option compared to meat and other animal products (Bell & Waagbø, 2008 ). However, fish consumption also represents a significant pathway for pesticide exposure, potentially raising the levels of these compounds in humans. Environmental contamination can turn fish into a source of hazardous substances, particularly persistent organic pollutants (POPs) (Sun et al., 2006 ). Previously, several studies have been conducted on the physicochemical parameters of Lake Zuway water (Gebremedhin, 2015 ; Merga et al., 2020 ; Teklu et al., 2018 ), while more recent research by Habtamu ( 2020 ) and Merga et al. ( 2021 ) has examined the impacts of pesticides, nutrients, and heavy metals in the lake. However, these studies have mostly concentrated on organochlorine pesticides (OCPs), and the results have been inconsistent, likely due to differences in test methods, sampling procedures, and pesticide degradation. Furthermore, as Lake Ziway is a closed ecosystem and undergoes significant evaporation, the accumulation of chemical pollutants like pesticides is expected to increase or change within the fish populations. Overall, there is insufficient research on the wide range of persistent organic pollutants, particularly pesticides, and their associated health risks in the fish of Lake Ziway using highly selective and sensitive analytical techniques. This study, therefore, aims to assess the accumulation of selected pesticides in different edible fish species, evaluate the health risks associated with fish consumption, and determine the levels of organochlorine (OC), organophosphorus (OP) pesticides, and certain carbamates. The study will also compare pesticide residues to worldwide permissible limits to evaluate the potential health risks associated with consuming contaminated fish species Materials and Methods The Study Area Description Lake Ziway (Fig. 1 ), is found in Ethiopia with a specific location between 7 o 51' to 8 o 07'N and 38 o 43' to 38 o 56'E with an altitude of 1636 m asl, at a distance about 160 km to the south of Addis Ababa, the capital city of Ethiopia. The location has a sub-humid climatic condition, with a mean annual average minimum and maximum temperatures range of 13.4–14.2 o C and 27.5–28.7 o C, respectively (Merga et al., 2020 ). Lake Ziway is a freshwater, historically its formation began approximately 10,000 years ago and covers a surface area of about 434 km 2 (Tibebe et al., 2022 ). It has an average depth of 4.2 m ends to a maximum depth of 9 m (Merga et al., 2020 ). The Meki and Katar Rivers contribute water to the lake (Goshime et al., 2021 ), and its outflow is discharged into the Bulbula River, which further goes to Lake Abeyta as terminal destination (Goshime et al., 2021 ). Sample Collection and Preparation A total of forty-eight fishes, four fishes for a single group with almost the same size classified and composited into three groups for each fish species to make a total of twelve samples were collected from local fishermen upon landing at Lake Ziway in the dry season of May (Table 1 ). Fish species with high-fat contents and consumer preferences; indigenous Nile tilapia ( Oreochromis niloticus ), introduced African sharp-tooth catfish ( Clarias gariepinus ), Carassius carassius and common carp ( Cyprinus carpio ) were included in the current study. The length (cm) and weight (g) of each fish were registered. Then, its body was dissected to obtain the dorsal portion of the fish, above the lateral line between the head and the dorsal fin at Ziway Fishery Laboratory. The dissected samples were washed with Milli-Q water and wrapped using aluminum foil, placed in an icebox before transporting to the laboratory; and stored at -20 o C. The muscle tissue was fully thawed, cut into small pieces, and homogenized. The dorsal muscle part of the four fishes of almost the same length for each class of each fish species was composited and homogenized to obtain a single sample. All pooled samples were lyophilized using a Buchi LyovaporTM L-200 Pro freeze dryer. Sufficient dried sample ground to yield at least 10 to 20 g after grinding. Table 1 Size of investigated fish species Types of fish Group 1 Group 2 Group 3 Length (cm) Weight (g) Length (cm) Weight (g) Length (cm) Weight (g) common carp ( Cyprinus carpio ) 23.5 145.1 25 227.4 30 369 22.5 138.6 25.5 215.5 29 357.6 22.5 134.7 26.5 236.8 30 365.3 22 134.2 26 229 30.5 366 Catfish ( Clarias gariepinus ) 28 173.9 34 301.4 40 407.7 29 249.9 33 291.6 38 382.8 28.5 201.3 33 290 37 390.6 29 253.7 32 287.9 37.5 396.2 Nile Tilapia ( Oreochromis niloticus) 15 58.1 18 106.1 25 201.4 14.5 57.6 17.5 100.1 23 198.6 13.5 56.2 18 112.9 22 191.6 14.7 57.9 17.9 103.4 24 200.5 Crucian carp (Carassius Carassius) 19 186.3 23.5 247.3 26 260.9 19 181.4 24 250.6 26 265.3 20 192.8 24 251.8 27 268.7 19.5 183.7 23.7 249.8 26.5 267.3 Sample Extraction and Analysis The fish samples were extracted at the Ethiopian Food and Drug Authority (EFDA) laboratory. The samples were extracted using a pressurized liquid extraction technique of Buchi Speed Extractor E-916 fitted with 40 mL stainless steel cells. The cell was utilized by fitting with the two cellulose filters. About 5 g of each composited sample was mixed with 5 g of diatomaceous earth and loaded into 40 mL extraction cells to perform the extraction process in duplicate. The extraction process was undertaken in three cycles. The analytes were recovered with a mixture of n-hexane/dichloromethane (50:50) in three static extraction cycles of 10 min each, at 100 o C and 100 bar. The total flush time of the cell with solvent and gas were 2 min and 5 min, respectively. The raw extracts were collected in 240 mL vials and evaporated using a Buchi R-300 rotary evaporator. The dried extract was dissolved using hexane and transferred to test tubes to reduce the volume to about 2 mL using a gentle stream of nitrogen in an organomation OA-HEAT concentrator. The samples were then cleaned up using an active 1 g Florisil column (Florisil cleanup, EPA 3620B method) and finally, the volume was made into 10 mL volumetric flasks for quantification. A list of pesticides targeted for analysis was identified by surveying those widely applied by farmers surrounding Lake Ziway and by reviewing previous research works. Hence, the OCPs, OPPs, and CMs that were investigated are listed with their properties in Table 2 . Table 2 List of investigated pesticides Pesticides Formula Aldrin C 12 H 8 Cl 6 Dieldrin C 12 H 8 Cl 6 O Cis-chlordane C 10 H 6 Cl 8 trans-Chlordane C 10 H 6 Cl 8 p,p’- DDT C 14 H 9 Cl 5 p,p’- DDE C 14 H 8 Cl 4 p,p’- DDD C 14 H 10 Cl 4 Endosulfan-α C 9 H 6 C l6 O 3 S Endosulfan-sulfate C 9 H 6 Cl 6 O 4 S Heptachlor C 10 H 5 Cl 7 Heptachlor-epoxide C 10 H 5 Cl 7 O Hexachlorobenzene (HCB) C 6 Cl 6 α-HCH C 6 H 6 Cl 6 β-HCH C 6 H 6 Cl 6 Lindane (γ-HCH) C 6 H 6 Cl 6 Methoxychlor C 16 H 15 Cl 3 O 2 Chlorpyrifos- methyl C 7 H 7 Cl 3 NO 3 PS Chlorpyrifos C 9 H 11 Cl 3 NO 3 PS Diazinon C 12 H 21 N 2 O 3 PS Profenofos C 11 H 15 BrClO 3 PS Propoxur C 11 H 19 NO 3 Bendiocarb C 11 H 13 NO 4 All targeted pesticides were analyzed using 7890B model Agilent gas chromatography coupled to a 7000D model triple quadrupole mass spectrometer detector (GCMSMS). HP-5ms capillary column having a dimension of 30 m×0.25 mm i.d.×0.25-µm film thickness was used. Helium was used as a carrier gas with a constant flow rate of 1 mL min − 1 . 1 µL of the samples were injected in a splitless mode to split splitless inlet at a temperature of 280°C. Starting from 60°C and holding for 1 min, the oven temperature was risen to 170°C at the rate of 40°C min − 1 and to 250°C at the rate of 5°C min − 1 and finally to 300°C by 10°C min − 1 to hold for 3 min. The transfer line temperature was kept at 280°C. The triple quadrupole mass spectrometer was equipped with an EI source operated at 70 eV. The temperature of the MS ion source was set at 230°C and both quadrupole temperatures were kept at 150°C. Helium and nitrogen were used as quenching and collision gases with a flow rate of 2.25 mLmin − 1 and 1.5 mLmin − 1 , respectively. The Agilent MRM database was used for data acquisition; for each analyte, three MRM transitions were acquired, and two of them were used as confirmatory using their qualifier ratio. Quantification of residual pesticides was performed in duplicate against external reference standards using Agilent quantitative software version 10.0. Laboratory Quality Control The quality of results was ensured with duplicate measurements and recovery analysis. The average recoveries of the spiked standards were 60–120% for most compounds, except for dieldrin (51.33%) and bendiocarb (121.86%). Quantitatively, the pesticide residue was determined by an external standard method using Sigma Aldrich analytical grade chemicals and reagents. The calibration curves were drawn by injecting eight different concentrations of the pesticide standards. Correlation coefficient ( r 2 ) values obtained from calibration curves were > 0.993 in all cases. A signal-to-noise ratio-based calculation of the limit of detections (LOD) and limit of quantifications (LOQ) were also performed for each pesticide detection (Wenzl et al., 2016 ). The LODs were confirmed by the concentrations of analytes whose signal-to-noise (S/N) ratio was three and ranged from 0.010 to 0.034 µg kg − 1 in the fish samples. Those samples with concentrations detected less than LODs were treated as not detected (n.d.). A single standard was tested every 10 samples throughout the whole procedure to ensure that the system was repeatable and free of any carryover. Identification of the pesticides was done based on the retention time and qualifier to quantifier ratio of ions peak area while quantification was done by using quantifier ion peak area. Human Health Risk Assessment Dietary exposure assessment Pesticide health risks associated with daily exposure were evaluated using the USEPA's guidelines. Estimated daily intake (EDI) was calculated at a daily consumption level of 0.027 kg per day − based on FAO data (FAO, 2011 ). The average body weight of an Ethiopian adult used for the calculation was 60 kg as obtained from FAO (FAO, 2011 ). According to Eq. 1 , dietary exposure to the specific residue of contaminated fish is assessed by calculating the EDI based on average pesticide concentrations measured in each fish species (Joseph et al., 2021 ; Tekin & Pazi, 2017; Witczak et al., 2021). $$\:EDI\:(\left(\frac{mg}{kg}\right)\times\:da{y}^{-\:})=\frac{C\times\:CR}{BW}\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:(Eq.\:1)$$ Where C is the average concentration of pesticide measured in fish (mg kg − 1 ), CR is the average daily fish consumption rate (kg day − 1 ), and BW is the assumed average body weight (kg). Risk characterization The calculated daily consumption was compared to the recommended reference doses (RfD) to assess for non-carcinogenic effects. The Reference Dose is an estimate of daily exposure to the human population that is probably not associated with a significant lifetime risk of harmful effects, with uncertainty ranging maybe an order of magnitude(USEPA, 2000a ). The Hazard Quotient was determined by Eq. 2 . When the Hazard Quotient (HQ) 1, it is not acceptable. $$\:HQ=\frac{EDI}{ARfD}\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:(Eq.2)$$ Estimates of carcinogenic risk are expressed as the likelihood that a person would develop cancer throughout a lifetime of being exposed to pesticide residue. Eq. 3 was used to determine the hazard ratio (HR) for the carcinogenic risk assessment (Dougherty et al., 2000 ). $$\:HR=\frac{EDI}{CBC}\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:(Eq.3)$$ Where CBC is the cancer benchmark concentration. The formula CBC for carcinogenic impact was determined by setting the risk of lifetime exposure to the pesticide residue at 1 in 1,000,000: $$\:CB=\frac{RL\times\:BW}{CR\times\:OSF}\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:(Eq.4)$$ Where, RL is the highest tolerable risk level (1 × 10 − 6 ) and OSF stands for oral slope factor (mg/kg/d), CR for fish consumption rate (g/day), and BW for body weight (kg) (USEPA, 2000a ). Oral slope factor values were obtained from the USEPA’s integrated risk information system (IRIS) (USEPA, 2000a ). As of USEPA ( 2000a ), a risk level below 10 − 6 (acceptable), between 10 − 6 and 10 − 4 (considered) is found in an area of concern, and RL greater than 10 − 4 (high cancer risk) (Dougherty et al., 2000 ). With this definition, an HR ≥ 1 implies a risk level of one in a million-lifetime, showing a potential risk to human health (Dougherty et al., 2000 ). The health risk assessment was conducted on six parameters; ΣDDT was the sum of p,p’ -DDT, p,p’ -DDD, p,p’ -DDE; HCH, Hexachlorobenzene; Σheptachlor was the sum of heptachlor and heptachlor epoxide; diazinon and chlorpyrifos. Data analysis Descriptive statistical analysis was conducted with SPSS version 26. The mean values of each pesticide concentration in the fish species were compared using a one-way ANOVA. To determine the association between fish size and POP concentrations, POP concentrations (µg kg − 1 ) were regressed against total fish length, weight, and fish species as a categorical variable. Microsoft Excel is used for calculations to determine the health risk of the consumption of pesticide-contaminated fish and their compliance with international regulations and European Union MRL values. Results and Discussion Pesticide Concentrations in Fish Samples The present study designated 22 compounds belonging to OCP, OPPs, and Carbamates in the four fish species. The chromatographs below (Fig. 2 and Fig. 3) are selected to show the chromatograms detected using the GCMS triple quadrupole technique. All chromatogram results of the samples, standards, calibration curves, and their response are attached in Appendices. The results of all pesticide concentrations are summarized as arithmetic averages in (µg kg − 1 ) in Table 3 . The analysis revealed the presence of 45% of the pesticides and the remaining 55% were not found above the limit of detection in any sample analyzed. As listed in Table 3 , α -HCH, HCB, Heptachlor, heptachlor epoxide, p,p’- DDD, p,p’ -DDT, p,p’- DDE, chlorpyrifos, propoxur, diazinon were detected while β-HCH, γ-HCH, aldrin, dieldrin, endosulfan I, endosulfan sulfate, bendiocarb, profenofos, chlordane-trans, chlordane-cis, methoxychlor, chlorpyrifos-methyl are pesticides existed in less than detection limit (Appendix 4). According to the European Union guidelines for maximum residue levels (MRL) of pesticides, the analysis of pesticide residues in the samples revealed that DDTs, diazinon, and propoxur were found to have levels higher than the MRL (EU, 2005 ). However, other positively detected pesticides were found to be below the MRL threshold. Levels of OCPs The concentrations of OCPs ranged from 12.77 to 163.93 µg/kg, with a mean concentration of 65.45 µg kg − 1 . The p,p’ -DDT, p,p’- DDE, p,p’- DDD, HCB, α -HCH, and heptachlor were found in every sample. The concentration of DDTs existed ranges from 12.33–162.40 µg kg − 1 . Other pesticides detected in all fish species were hexachlorobenzene (HCB) at concentrations up to 1.13 µg kg − 1 , heptachlor at concentrations from 0.1 µg kg − 1 up to 0.97 µg kg − 1 and α -HCH found up to 0.1µg/kg (Table 3 ). Heptachlor epoxide was found in only catfish species at concentrations up to 0.02 µg/kg. Fish samples found in this investigation often showed an OCP contamination pattern that was DDTs > HPTs > HCB > HCHs. This finding suggests that the biota around the Lake has been exposed to a high level of DDTs. DDTs level in another Ethiopian lake are likewise significantly higher than those of other POPs. The mean concentration of DDTs in Lake Koka was reported ten times higher than that of other POPs (Deribe et al., 2011). Similarly, it has been reported that the biota in Lake Malawi has been exposed to DDT concentrations up to 60 times greater than those of other organochlorine pesticides (Kidd et al., 2001). DDTs DDTs were the most often found and predominated in all samples of the OCPs examined. The concentration ranges from (12.33 to 162.40 µg kg − 1 ) and accounts for 97.97% of the total OCPs. Within the DDT series, p,p’- DDE, the most stable isomer, found at the highest concentrations from 10.75 µg kg − 1 up to 148.9 µg kg − 1 accounted for 84.97% of the total DDTs, an indication of non-recent exposure. The other DDT constituent was p,p’- DDD, which was found in all of these samples at concentrations up to 8.05 µg kg − 1 (Table 4 ). The p,p’- DDT ranges from ( 1.25 to 8.96 µg kg − 1 ) to account for 7.39% of the total OCPs. The proportions of the metabolites ( p,p’ -DDD and p,p’ -DDE) indicated that aerobic degradation was the dominant degradation pathway as the concentrations of p,p’- DDE were greater than the concentrations of p,p’- DDD in all the fish samples. These metabolites are formed by aerobic degradation and anaerobic degradation, respectively, in the environment and organisms (Mahugija et al., 2018 ). As summarized in Table 4 , the highest mean concentration of p,p’- DDE and p,p’- DDD isomers were detected in catfish as 148.9 µg/kg and 8.05 µg/kg, respectively; these differed significantly (p < 0.05) compared with the p,p’- DDE and p,p’- DDD content of other fish species. The lowest concentrations of p,p’- DDE and p,p’- DDD were found in Nile Tilapia 10.75 µg kg − 1 and 0.33 µg kg − 1 , respectively (Table 4 ). Whereas, the highest concentration of p,p’- DDT is found in Cyprinus carpio and the lowest is in the Nile Tilapia fish species (P < 0.01). The ratios of p,p’- DDE and p,p’- DDT in Nile Tilapia, Carassius Carassius, Cyprinus carpio, and Catfish were 8.6, 8.67, 2.93, and 27.32, respectively. The DDE to DDT ratio is a useful tool for assessing DDT degradation and evaluating the current use of DDT in a specific environment (Strandberg & Hites, 2001 ). Observed mean values of p,p'- DDE to p,p'- DDT ratios greater than 1 in the case of all the four fish species suggests that there is long-term bio-transformation of DDT and fish species have experienced almost no recent exposure to DDT (Strandberg and Hites, 2001 ). This finding is supported by a study conducted by Mergia et al. ( 2021 ), which also found no recent exposure to DDT in fish species in Lake Ziway. However, another recent study conducted by Habtamu ( 2020 ), revealed the presence of recent application of DDT in the Lake Ziway catchment area. Table 3 List of target pesticides analyzed and its concentration Target Analyte Range (µg kg − 1 ) Minimum (µg kg − 1 ) Maximum (µg kg − 1 ) Sum (µg kg − 1 ) Mean (µg kg − 1) Std. Deviation α -HCH 0.04 0.06 0.1 0.34 0.09 0.02 Hexachlorobenzene 0.9 0.23 1.13 2.57 0.64 0.37 β-HCH n.d. n.d. n.d. n.d. n.d. n.d. Lindane n.d. n.d. n.d. n.d. n.d. n.d. Heptachlor 0.87 0.1 0.97 2.07 0.52 0.36 Heptachlor epoxide 0.02 0 0.02 0.04 0.01 0.01 Aldrin n.d. n.d. n.d. n.d. n.d. n.d. Dieldrin n.d. n.d. n.d. n.d. n.d. n.d. Chlordane, trans n.d. n.d. n.d. n.d. n.d. n.d. Chlordane, cis 0.3 0 0.3 0.3 0.08 0.15 Endosulfan_ I n.d. n.d. n.d. n.d. n.d. n.d. Endosulfan sulphate n.d. n.d. n.d. n.d. n.d. n.d. p,p’- DDE 138.15 10.75 148.9 217.95 54.49 63.58 p,p’- DDD 7.72 0.33 8.05 19.17 4.79 3.28 p,p’- DDT 7.71 1.25 8.96 19.36 4.84 3.24 Methoxychlor n.d. n.d. n.d. n.d. n.d. n.d. Chlorpyrifos 5.46 0.42 5.88 7.75 1.94 2.63 Chlorpyrifos_ methyl n.d. n.d. n.d. n.d. n.d. n.d. Diazinon 10.09 2.46 12.55 33.72 8.43 4.26 Propoxur 62.47 3.82 66.29 141.87 35.47 25.55 Bendiocarb n.d. n.d. n.d. n.d. n.d. n.d. Profenofos n.d. n.d. n.d. n.d. n.d. n.d. ∑Heptachlor 0.85 0.12 0.97 2.11 0.53 0.35 ∑DDT 150.07 12.33 162.4 256.48 64.12 66.89 ∑OCP 151.16 12.77 163.93 261.8 65.45 67.14 Fish Length (cm) 14.66 18.59 33.25 101.11 25.28 6.15 Fish weight (g) 181.88 120.37 302.25 899.71 224.93 76 Among the four fish species studied, the highest mean concentration of DDTs residues was noted in the Catfish, while the lowest was in the Nile Tilapia (P Cyprinus carpio > Carassius Carassius > Nile Tilapia clearly shows the biomagnification of DDTs in high trophic levels which can be known unanimously based on their feeding habit and biomagnification factor study done by (Mergia et al., 2021 ). Another study conducted on Lake Hawassa which exists in the same rift valley region also revealed the concentration of DDTs in catfish is higher than the Nile tilapia (Deribe et al., 2014 ). In another country, a study conducted in Egypt reported there is a higher rate of pesticide accumulation in catfish (C.gariepinus) compared to Nile tilapia (O. niloticus) from the same location (Yahia & Elsharkawy, 2014 ). Table 4 Concentration of pesticides in fish species Target Analyte Mean concentration (µg/kg) Nile Tilapia Carassius carassius Cyprinus carpio Catfish Hexachlorobenzene 0.23 1.13 0.61 0.6 Alpha-lindane (α -HCH) 0.09 0.1 0.06 0.09 Beta lindane (β-HCH) n.d. n.d. n.d. n.d. Gamma (Lindane) n.d. n.d. n.d. n.d. Heptachlor 0.1 0.46 0.97 0.54 Heptachlor_epoxide 0.02 0.02 n.d. n.d. Aldrin n.d. n.d. n.d. n.d. Dieldrin n.d. n.d. n.d. n.d. Chlordane_trans n.d. n.d. n.d. n.d. Chlordane_cis n.d. n.d. n.d. 0.3 Endosulfan_I n.d. n.d. n.d. n.d. Endosulfan_sulfate n.d. n.d. n.d. n.d. p,p’- DDE 10.75 32.08 26.22 148.9 p,p’- DDD 0.33 4.7 6.09 8.05 p,p’- DDT 1.25 3.7 8.96 5.45 Methoxychlor n.d. n.d. n.d. n.d. Chlorpyrifos 0.42 0.81 0.64 5.88 Chlorpyrifos_methyl n.d. n.d. n.d. n.d. Diazinon 2.46 9.41 9.3 12.55 Propoxur 3.82 34.18 66.29 37.58 Bendiocarb n.d. n.d. n.d. n.d. Profenofos n.d. n.d. n.d. n.d. ∑Heptachlor 0.12 0.48 0.97 0.54 ∑DDT 12.33 40.48 41.27 162.4 ∑OCP 12.77 42.19 42.91 163.93 Fish Length (cm) 18.59 23.18 26.08 33.25 Fish weight (g) 120.37 233.83 243.27 302.25 HCHs From the isomers of HCH, only α -HCH is detected in fish species; whereas the remaining β-HCH, γ-HCH isomers are less than the detection limit in all fish species. HCHs accounted for 0.1% of the total OCPs measured. There are no statistically significant differences (p > 0.05) in the content of HCH isomer in all four fish species. Based on the finding, it can be inferred that the nonexistence of γ-HCH (lindane) concentrations in the samples indicates that there is no current usage of lindane around the Lake. Results of other researchers revealed conflicting trends; for instance, Mergia et al. ( 2021 ), suggested all HCHs are not detected, whereas the results from Yohannes et al. ( 2014 ), revealed all are significantly positive results in all fish species. HCB, HPTs, CHLs and Other OCPs HCB accounted for 0.8% of the total OCPs measured in the studied fish species. HPTs (the sum of heptachlor and heptachlor epoxide) were present in all of the fish species with no significant differences in amount (p > 0.05) in all four fish species. Cis chlordane (CHL) is above the detection limit only in catfish. The remaining investigated OCPs, which include dieldrin and aldrin, trans chlordane, α-endosulfan, endosulfan sulfate, and methoxychlor, are presumably less than the detection limit in all fish species probably due to the prohibition of their usage. Similar to the above comparisons, these results are still conflicting with previous studies on the Lake; Mergia et al. ( 2021 ), suggested all HCB, HPTs, CHLs, dieldrin and aldrin, trans chlordane, α-endosulfan, endosulfan sulfate, and methoxychlor are less than the detection limit. However, HCB, HPTs, and CHLs are positive according to (Yohannes et al., 2014 ). Levels of OPPs Organophosphate pesticides tested were only diazinon, chlorpyrifos and chlorpyrifos-methyl. Chlorpyrifos methyl was less than the detection limit, while diazinon and chlorpyrifos were detected in all fish species. Diazinon concentration ranges from 2.46 to 12.55 µg/kg and accounted for 7.58% of the total pesticides; whereas, chlorpyrifos concentration varied from 0.42 to 5.88 µg/kg and made up only 1.74% of the total pesticide. In catfish, mean values of 5.88 and 12.55 µg/kg chlorpyrifos and diazinon were respectively detected to be significantly differing from other fish species (P < 0.05). The only previous study conducted by Mergia et al. revealed diazinon and chlorpyrifos are found to be less than the detection limit (Mergia et al., 2021 ). However, as support of the current research, diazinon and chlorpyrifos are the types of OPPs registered in Ethiopia and are frequently utilized by small-scale vegetable producers primarily on cabbage, onion, and tomato along the littoral region of the Lake (Mengistie et al., 2017). Level of Carbamates Based on the findings, propoxur was detected in all fish species, with concentrations ranging from 3.82 to 66.29 µg/kg. It constituted 31.87% of all persistent organic pollutants (POPs) that were examined. The amount of propoxur detected in Cyprinus carpio (common carp), 66.29 µg/kg was significantly different from other species (p < 0.05). The content of propoxur was lowest in Nile tilapia and greatest in Cyprinus carpio fish species. No research has been conducted on carbamates in Lake Ziway including propoxur and bendiocarb, to compare for additional information. Relation of Fish Size with Pesticides Accumulation Except for a single value of chlorpyrifos, all pesticides were progressively increasing in concentrations within C. gariepinus fish species of different sizes. The length and weight distribution of analyzed Nile Tilapia , carassius carassius , and cyprinus carpio were very narrow primarily due to the small size of individuals. Thus, the concentration of pesticides within these species did not rise noticeably with size. Based on this study, it appears that length and weight increased along with each other for all individuals of the studied fish species with a positive and strong correlation of R 2 value, 0.877, and a p -value of 0.064. The findings of Yohannes et al. ( 2014 ) and Zhang et al. (2013) also revealed similar correlations between length and weight in fish species. As indicated in Table 5 , the length and weight of the studied fish species varied within the range of 18.59 cm to 33.25 cm and 120.37 g to 302.25 g, respectively. With all data composited for the four fish species, DDTs, chlorpyrifos, and diazinon were progressively increased with the fish size. As the R 2 value in Table 5 indicates, the mean concentration of p,p’- DDE, p,p’- DDD, diazinon, chlorpyrifos, and chlordane-cis show a positive correlation with the size of all fish species. The increase in the concentration of DDT metabolites, such as p,p'- DDE and p,p'- DDD, suggests that the biomagnification of hydrophobic organic compounds is dependent on metabolism capacity and octanol-water partition coefficients (Kow) (Zhang et al., 2013). However, no significant correlation was found between the size of the fishes (length or weight) and concentration of p,p’ -DDT, heptachlor, hexachlorobenhbn mbbbbzene, heptachlor epoxide, α -HCH. The lack of correlation between pesticide concentrations and other factors in fish can be attributed to several reasons. One possible reason is the low concentration of pesticides detected, which may not be consistent enough to establish a strong correlation. Additionally, the decrease in the concentration of p,p’ -DDT is likely due to Metabolization. Metabolization refers to the process by which a substance, in this case, p,p’- DDT, is broken down and transformed within an organism. Chemicals that are metabolized and eliminated by organisms normally show low biomagnification potentials (Deribe et al., 2011).le 5 Table 5 Correlation of pesticides and fish size Target Analyte P -value R 2 Length (cm) Weight (g) Length (cm) Weight (g) Hexachlorobenzene 0.799 0.483 0.040 0.267 HCH-alpha 0.859 0.883 0.020 0.014 Heptachlor 0.475 0.347 0.275 0.426 Heptachlor epoxide 0.175 0.273 0.680 0.528 Chlordane-cis 0.135 0.322 0.748 0.460 DDE -p,p' 0.088 0.230 0.832 0.592 DDD -p,p' 0.056 0.008 0.892 0.985 DDT -p,p' 0.422 0.340 0.335 0.436 Chlorpyrifos 0.116 0.284 0.781 0.512 Diazinon 0.090 0.003 0.828 0.994 Propoxur 0.456 0.309 0.295 0.478 Sum of DDT 0.059 0.188 0.886 0.660 As illustrated in Fig. 4 , the total pesticide concentration is also significantly higher in C. gariepinus (Catfish). The biomagnification pathway of uptake may be significant for fish in their natural habitats, particularly for benthic-based food webs and highly lipophilic pollutants. Since DDT eventually converts to DDE and DDD, larger individuals of these species most likely accumulate a more degraded form of the pesticide. Lipophilic POPs like DDT can bioaccumulate and biomagnify with increasing trophic levels, larger concentrations of POPs exist in fatty or predatory fish species than small fish at lower trophic levels (Gupta et al., 2022 ). As pointed out by Adegun et al. ( 2020 ), length and weight are vital variables for explaining the variation in concentrations of POPs. Therefore, larger fish, which are often the target of commercial and recreational fishing, may pose a greater risk for human consumption due to their higher pesticide content. Additionally, the role of larger fish as predators means that their contamination reflects a broader issue of pesticide magnification throughout the trophic levels of aquatic ecosystems (Sharma et al., 2009 ). The health of these ecosystems and the species within them may be compromised by the pervasive presence of pesticides, which can have wide effects on biodiversity. Human Health Risk Assessment Estimation of daily intake (EDI) Fish consumption is one way that contaminants can enter the human body. To determine the possible exposure of humans to persistent organic pollutants (POPs), Estimated Daily Intake (EDI) values are calculated using the average concentration of target contaminants in several fish species. As summarized in Table 6 , the estimated daily intake (EDI) of DDTs was the highest, while α-HCH had the lowest EDI, aligning with the concentration trends observed in the fish species. The health risk is also attributed to the type of fish in which its pesticide accumulation capacity was observed differently (Table 7 ). Table 6 Health risk associated with the daily intake of pesticides Target Analyte Mean, Residue level (mg/kg) Oral RfD (mg/kg/day) Cancer Slope factor (mg/kg/day) CBC (mg/kgbw/d) EDI(Adult) (mg/kgbw/d) Non-carcinogenic Risk (HQ) Cancer Risk (HR) α -Lindane 8.50x10 − 5 0.008 6.3 1.12x10 − 1 3.83x10 − 8 4.78x10 − 6 3.41x10 − 7 HCB 6.43x10 − 4 0.0008 1.6 5.84x10 − 2 2.89x10 − 7 3.61x10 − 4 4.95x10 − 6 Heptachlors 5.28x10 − 4 0.0005 4.5 2.53x10 − 2 2.37x10 − 7 4.75x10 − 4 9.39x10 − 6 DDTs 6.41x10 − 2 0.0005 0.34 2.75x10 − 3 2.89x10 − 5 5.77x10 − 2 1.05x10 − 2 Chlorpyrifos 1.94x10 − 3 0.0003 NA* NA 8.72x10 − 7 2.91x10 − 3 NA Diazinon 8.43x10 − 3 0.0007 NA NA 3.79x10 − 6 5.42x10 − 3 NA NA: data not available in USEPA database. Risk assessment Non-carcinogenic risk assessment To evaluate the potential noncarcinogenic health risks of consuming persistent organic pollutants (POPs) through diet, the daily intakes were compared to the maximum acceptable daily intake values (reference doses, RfDs) using the standard formula explained (Yu et al., 2012 ). As summarized in Table 6 , the estimated daily intake of all POPs investigated in Ziway Lake is lower than their respective RfD values, indicating that they do not pose a non-carcinogenic health risk. Specifically, α-HCH, despite being present in all fish species, is significantly lower than its RfD value for non-carcinogenic effects. Similarly, a study conducted by Yohannes et al. ( 2014 ), in the same location also reported no non-carcinogenic health risks associated with these pesticides. Additionally, studies conducted in China have also suggested that fish consumption would not pose a non-cancer risk (Cui et al., 2015 ; Yu et al., 2014 ). The non-carcinogenic risk value (HQ < 1) indicates that there is a low risk of adverse health effects from fish consumption. However, it does not assure that there is no probable health risk associated with fish consumption. This study revealed the levels of DDTs and diazinon in all fish species exceeded the EU's recommended MRL threshold. This suggests the pollutants could still accumulate in the human body and potentially cause health concerns. Furthermore, the study did not consider the possibility of synergistic effects when multiple pesticides or pollutants are present simultaneously. Table 7 Health risks based on fish species Target analytes Fish species Nile Tilapia C. carassius Cyprinus carpio Catfish Non-carcinogenic Risk (HQ) Cancer Risk (HR) Non-carcinogenic Risk (HQ) Cancer Risk (HR) Non-carcinogenic Risk (HQ) Cancer Risk (HR) Non-carcinogenic Risk (HQ) Cancer Risk (HR) α -HCH 5.06x10 − 6 3.83x10 − 7 5.63x10 − 6 4.73x10 − 7 3.38x10 − 6 1.70x10 − 7 5.06x10 − 6 3.83x10 − 7 HCB 1.29x10 − 4 6.35x10 − 7 6.36x10 − 4 1.53x10 − 5 3.43x10 − 4 4.47x10 − 6 3.38x10 − 4 4.32x10 − 6 HPTs 1.08x10 − 4 4.86x10 − 7 4.32x10 − 4 7.78x10 − 6 8.73x10 − 4 3.18x10 − 5 4.86x10 − 4 9.84x10 − 6 DDTs 1.11x10 − 2 3.88x10 − 4 3.64x10 − 2 4.18x10 − 3 3.71x10 − 2 4.34x10 − 3 1.46x10 − 1 6.73x10 − 2 Chlorpyrifos 6.30x10 − 4 NA 1.22x10 − 3 NA 9.60x10 − 4 NA 8.82x10 − 3 NA Diazinon 1.58x10 − 3 NA 6.05x10 − 3 NA 5.98x10 − 3 NA 8.07x10 − 3 NA Carcinogenic risk assessment This risk assessment was conducted to assess the carcinogenic effects of OCPs by using cancer risk estimates and HRs. The analysis in Tables 6 and 7 showed that fish consumption linked to α-HCH, HCB, and HPTs contamination posed a negligible cancer risk, with the calculated risks being almost less than 1x10 − 6 , indicating low concern. However, the cancer risk associated with DDTs exceeded 1x10 − 4 in all fish species, indicating that the potential risk from consuming fish contaminated with DDTs should not be ignored. It is crucial to acknowledge these findings and consider further research and measures to mitigate the risks and ensure the safety of our food sources. The levels of cancer risk exposure to DDTs varied across fish species, ranging from 3.88x10 − 4 in O. niloticus to 6.73x10 − 2 in C. gariepinus . This suggests that an adult human being would have a chance of approximately 4 in 10,000 to 7 in 100 of developing cancer from DDTs, respectively. Overall, consuming any fish species contaminated with DDTs would result in a lifetime cancer risk since it is greater than one in a million. Therefore, the current carcinogenic risk associated with DDTs should be a concern, predominantly in the case of the largest fish species, C. gariepinus . To minimize exposure to contaminants in fish, it is advisable to consume smaller and younger fish, as they generally have lower concentrations of contaminants. These findings align with previous research conducted at Lake Ziway by Yohannes et al. ( 2014 ), as well as studies conducted in South Africa and China, which also indicated a cancer risk associated with DDTs in fish consumption (Pheiffer et al., 2018 ; Yu et al., 2014 ). Human health risks are influenced by various sources of uncertainty, including factors such as fish preparation and cooking methods, nutrition adequacy, prior health conditions, and the development of pregnancy in women. These factors can impact the health risk condition differently. In susceptible subgroups, even low levels of contamination can exacerbate their situations, leading to health stress that healthy persons do not often experience. It is important to consider these factors as essentials which may change the potential risk levels associated with contaminants (USEPA, 2000a ). Conclusion Lake Ziway exhibits relatively high levels of contamination from organochlorine pesticides (OCPs), organophosphorus pesticides (OPPs), and carbamates (CMs). Positive detections included Σ HCH, Σ DDTs, HCB, Σ heptachlor, chlorpyrifos, propoxur, and diazinon. However, aldrin, dieldrin, β-HCH, γ-HCH, endosulfan I, endosulfan sulfate, bendiocarb, profenofos, chlordane-trans, chlordane-cis, methoxychlor, and chlorpyrifos-methyl were below detection limits. DDTs were the most abundant contaminant, especially in the fatty African sharp-tooth catfish (C. gariepinus ). The pattern of OCP contamination in the fish species was found to follow the order: DDT > HPTs > HCB > HCH. The study also revealed the bioaccumulation and biomagnification of DDTs, diazinon, heptachlor, and chlorpyrifos, all of which were significantly related to the size of the fish species. The health risk assessment indicated that consuming all four fish species could pose cancer risks due to DDTs, particularly the catfish due to its size. While non-carcinogenic health risks were not observed, the levels of DDTs and diazinon in all fish species exceeded the EU's recommended maximum residue limit (MRL), suggesting that these pollutants could accumulate in the human body and pose health concerns. It is recommended that food web studies be conducted to gain reliable information on pesticide biomagnification at different trophic levels. Besides, future research should explore viable treatment options for removing pesticides from the water resource. Declarations Acknowledgment The authors have acknowledged the laboratory and research facility support of the Ethiopian Civil Service University, Ziway Fishery Laboratory, and the Ethiopian Food and Drug Authority (EFDA) laboratory. Corresponding author Correspondence to Mekonnen Maschal Tarekegn Authors contribution Mekonnen Maschal Tarekegn initiated the research concept, framed the methodology, supervised the laboratory activities, data collection, and analysis, and finalized the report including the manuscript preparation. Dagnachew Lelisa Duga initiated the research proposal, collected samples, carried out lab activities, performed the data analysis, wrote the report, and prepared the manuscript. Yitayal Addis Alemayehu participated in the supervision of laboratory activities, data collection, analysis, and report writing including manuscript preparation. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-6016451","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":429921174,"identity":"d4bb067e-386c-4ea3-ba55-c8189170ba4b","order_by":0,"name":"Mekonnen Maschal Tarekegn","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA30lEQVRIiWNgGAWjYJACZgYGCwY29uYDQLaEDLFaJBj4eI4lgLTwEK9FTiLHAMQhrEW3/fjDzwU1EtFsDDmfX92oseBhYD98dAM+LWZncoylZxyTyG1jOLvNOucY0GE8aWk38Go5kMPGzMMG1MLYu804hw2oRYLHDL+W88+fMfP8A2ph5nlmnPOPGC03EsyYeduAWth4mB/nthGl5Y2xNG8fUAsPmxlzbp8EDxtBv5xPf/iZ55tN7vz5jx9/zvlWJ8fPfvgYXi3IgE0CTBKrHASYP5CiehSMglEwCkYOAABMTkKQ7Owp1wAAAABJRU5ErkJggg==","orcid":"https://orcid.org/0000-0003-4694-873X","institution":"Ethiopian Civil Service University","correspondingAuthor":true,"prefix":"","firstName":"Mekonnen","middleName":"Maschal","lastName":"Tarekegn","suffix":""},{"id":429921175,"identity":"63ef8141-25ad-4a37-9800-4e880cce7cb5","order_by":1,"name":"Dagnachew Lelisa Duga","email":"","orcid":"","institution":"Ethiopian Civil Service University","correspondingAuthor":false,"prefix":"","firstName":"Dagnachew","middleName":"Lelisa","lastName":"Duga","suffix":""},{"id":429921176,"identity":"23393c7d-c51e-4c38-87bd-c473b54463de","order_by":2,"name":"Yitayal Addis Alemayehu","email":"","orcid":"","institution":"Kotebe University of Education","correspondingAuthor":false,"prefix":"","firstName":"Yitayal","middleName":"Addis","lastName":"Alemayehu","suffix":""},{"id":429921177,"identity":"d7db0564-f64e-40e9-92a4-a8d503ef87e6","order_by":3,"name":"Mitiku Adisu Worku","email":"","orcid":"","institution":"Ethiopian Civil Service University","correspondingAuthor":false,"prefix":"","firstName":"Mitiku","middleName":"Adisu","lastName":"Worku","suffix":""}],"badges":[],"createdAt":"2025-02-12 15:28:27","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-6016451/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6016451/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":78807761,"identity":"c3efb545-098f-4e74-b6e1-83ddc70b2344","added_by":"auto","created_at":"2025-03-19 08:23:38","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":105840,"visible":true,"origin":"","legend":"\u003cp\u003eMap of Lake Ziway\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-6016451/v1/47cfd241d985a6c7383ebc77.png"},{"id":78808118,"identity":"a7265fb7-2b4a-4afe-a128-7e1df737e888","added_by":"auto","created_at":"2025-03-19 08:31:38","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":26497,"visible":true,"origin":"","legend":"\u003cp\u003eChromatogram of Cat fish species sample (C3)\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-6016451/v1/8a17669b393627158299c15f.png"},{"id":78807779,"identity":"79e95fc3-6c74-480f-af18-37cf2b76c334","added_by":"auto","created_at":"2025-03-19 08:23:39","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":24489,"visible":true,"origin":"","legend":"\u003cp\u003eChromatogram of OCP standard with 50 µg kg\u003csup\u003e-1\u003c/sup\u003e\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-6016451/v1/221d097bfb2f81542a07aa90.png"},{"id":78808120,"identity":"59bfae31-b7dd-47bc-abdf-a6df6b65181b","added_by":"auto","created_at":"2025-03-19 08:31:39","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":26280,"visible":true,"origin":"","legend":"\u003cp\u003eComparison of fish species and total pesticide concentration\u003c/p\u003e","description":"","filename":"4.png","url":"https://assets-eu.researchsquare.com/files/rs-6016451/v1/1b68f9ac3054378064e4a1e7.png"},{"id":81600462,"identity":"7aa68b4e-1e04-403a-87fe-5e0310045491","added_by":"auto","created_at":"2025-04-29 03:54:45","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1447750,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6016451/v1/effa97d4-1457-4336-a775-85af68d6d3d0.pdf"}],"financialInterests":"","formattedTitle":"Assessment of Pesticide Contamination Level of Fish and Human Health Risks in Lake Ziway, Ethiopia","fulltext":[{"header":"Introduction","content":"\u003cp\u003eAnthropogenic activities, including the heavy use of agrochemicals, unsustainable land use, and municipal and industrial waste discharge, increasingly impact the quality of natural water bodies in many developing countries. Ethiopia, according to Awulachew et al. (\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e2007\u003c/span\u003e), is one of the African nations with the most significant water resources, including 275 km\u0026sup2; of smaller water bodies, 7185 km of rivers, and major lakes and reservoirs with an estimated surface area of 7334 km\u0026sup2; (Kebede et al., 2017). Lake Ziway, the second most important fishing hub in the country, is home to fifteen different fish species (Daniel, 2015).\u003c/p\u003e \u003cp\u003eFor generations, people living along Lake Ziway's shoreline have depended on its fishery for food and income, as it is a readily accessible and vital source of livelihood. Spliethoff et al. (\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e2009\u003c/span\u003e) estimate the potential yield from all the species in the lake to be between 2,500 and 6,680 tons per year. Additionally, the lake provides water to large-scale investors in horticulture and floriculture, as well as smallholder farmers. For the town of Ziway, the lake is a crucial source of drinking water and irrigation. Due to its freshness and low salinity, this water resource is highly valued by several sectors (Spliethoff et al., \u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e2009\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eHowever, in addition to the municipal waste discharges from Ziway, the past two decades have seen rapid growth in smallholder and large-scale export-oriented vegetable, fruit, and commercial floriculture farms along the shoreline, tributary rivers, and outflow river of Lake Ziway (Jansen et al., 2007). The extensive use of agrochemicals in these farms causes pollution. These chemicals are applied to boost agricultural productivity and control disease vectors, thereby ensuring food security (Mergia et al., \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e2021\u003c/span\u003e). However, when pesticides are used improperly, they pose risks to wildlife, the environment, and human health (Tibebe et al., \u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e2022\u003c/span\u003e).\u003c/p\u003e \u003cp\u003ePesticide residues from these farms may contaminate Lake Ziway and its fish species through various mechanisms, including runoff, drainage, and airborne deposition during application (Teklu et al., \u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e2018\u003c/span\u003e). Chemicals sequestered in the soil can be released into the lake via runoff and erosion from the surrounding catchment, where they may enter to the food chain and affect fish populations (Jansen \u0026amp; Harmsen, \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e2011\u003c/span\u003e). This poses a significant threat to the quantity and quality of fish species, which are essential for commerce, a key ecosystem service provided by Lake Ziway. Abera et al. (2018) estimated that the lake's annual fish supply has decreased by about 33%, from 3180 tons recorded by LFDP in 1997 to 1,157 tons, along with a shift in the species composition. In 1994, Carpio and O. niloticus contributed 0.12% and 89% respectively to the fish catch, while by 2014, C. carpio's share had increased to 28% and O. niloticus' had dropped to 50% (Abera et al., 2018).\u003c/p\u003e \u003cp\u003eFish contaminated with pesticides may absorb harmful chemicals, which can then enter the human food chain. Fish contain high proteins and vitamins that are considered a healthier dietary option compared to meat and other animal products (Bell \u0026amp; Waagb\u0026oslash;, \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e2008\u003c/span\u003e). However, fish consumption also represents a significant pathway for pesticide exposure, potentially raising the levels of these compounds in humans. Environmental contamination can turn fish into a source of hazardous substances, particularly persistent organic pollutants (POPs) (Sun et al., \u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e2006\u003c/span\u003e).\u003c/p\u003e \u003cp\u003ePreviously, several studies have been conducted on the physicochemical parameters of Lake Zuway water (Gebremedhin, \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e2015\u003c/span\u003e; Merga et al., \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e2020\u003c/span\u003e; Teklu et al., \u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e2018\u003c/span\u003e), while more recent research by Habtamu (\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e2020\u003c/span\u003e) and Merga et al. (\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e2021\u003c/span\u003e) has examined the impacts of pesticides, nutrients, and heavy metals in the lake. However, these studies have mostly concentrated on organochlorine pesticides (OCPs), and the results have been inconsistent, likely due to differences in test methods, sampling procedures, and pesticide degradation. Furthermore, as Lake Ziway is a closed ecosystem and undergoes significant evaporation, the accumulation of chemical pollutants like pesticides is expected to increase or change within the fish populations. Overall, there is insufficient research on the wide range of persistent organic pollutants, particularly pesticides, and their associated health risks in the fish of Lake Ziway using highly selective and sensitive analytical techniques.\u003c/p\u003e \u003cp\u003eThis study, therefore, aims to assess the accumulation of selected pesticides in different edible fish species, evaluate the health risks associated with fish consumption, and determine the levels of organochlorine (OC), organophosphorus (OP) pesticides, and certain carbamates. The study will also compare pesticide residues to worldwide permissible limits to evaluate the potential health risks associated with consuming contaminated fish species\u003c/p\u003e"},{"header":"Materials and Methods","content":"\u003cp\u003eThe Study Area Description\u003c/p\u003e \u003cp\u003eLake Ziway (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e), is found in Ethiopia with a specific location between 7\u003csup\u003eo\u003c/sup\u003e51' to 8\u003csup\u003eo\u003c/sup\u003e07'N and 38\u003csup\u003eo\u003c/sup\u003e43' to 38\u003csup\u003eo\u003c/sup\u003e56'E with an altitude of 1636 m asl, at a distance about 160 km to the south of Addis Ababa, the capital city of Ethiopia. The location has a sub-humid climatic condition, with a mean annual average minimum and maximum temperatures range of 13.4\u0026ndash;14.2 \u003csup\u003eo\u003c/sup\u003eC and 27.5\u0026ndash;28.7 \u003csup\u003eo\u003c/sup\u003eC, respectively (Merga et al., \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e2020\u003c/span\u003e). Lake Ziway is a freshwater, historically its formation began approximately 10,000 years ago and covers a surface area of about 434 km\u003csup\u003e2\u003c/sup\u003e (Tibebe et al., \u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e2022\u003c/span\u003e). It has an average depth of 4.2 m ends to a maximum depth of 9 m (Merga et al., \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e2020\u003c/span\u003e). The Meki and Katar Rivers contribute water to the lake (Goshime et al., \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e2021\u003c/span\u003e), and its outflow is discharged into the Bulbula River, which further goes to Lake Abeyta as terminal destination (Goshime et al., \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e2021\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eSample Collection and Preparation\u003c/p\u003e \u003cp\u003eA total of forty-eight fishes, four fishes for a single group with almost the same size classified and composited into three groups for each fish species to make a total of twelve samples were collected from local fishermen upon landing at Lake Ziway in the dry season of May (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). Fish species with high-fat contents and consumer preferences; indigenous Nile tilapia (\u003cem\u003eOreochromis niloticus\u003c/em\u003e), introduced African sharp-tooth catfish (\u003cem\u003eClarias gariepinus\u003c/em\u003e), \u003cem\u003eCarassius carassius\u003c/em\u003e and common carp (\u003cem\u003eCyprinus carpio\u003c/em\u003e) were included in the current study. The length (cm) and weight (g) of each fish were registered. Then, its body was dissected to obtain the dorsal portion of the fish, above the lateral line between the head and the dorsal fin at Ziway Fishery Laboratory. The dissected samples were washed with Milli-Q water and wrapped using aluminum foil, placed in an icebox before transporting to the laboratory; and stored at -20 \u003csup\u003eo\u003c/sup\u003eC. The muscle tissue was fully thawed, cut into small pieces, and homogenized. The dorsal muscle part of the four fishes of almost the same length for each class of each fish species was composited and homogenized to obtain a single sample. All pooled samples were lyophilized using a Buchi LyovaporTM L-200 Pro freeze dryer. Sufficient dried sample ground to yield at least 10 to 20 g after grinding.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eSize of investigated fish species\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"7\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eTypes of fish\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003eGroup 1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c5\" namest=\"c4\"\u003e \u003cp\u003eGroup 2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c7\" namest=\"c6\"\u003e \u003cp\u003eGroup 3\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003eLength (cm)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003eWeight (g)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003eLength (cm)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003eWeight (g)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003eLength (cm)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e\u003cb\u003eWeight (g)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"3\" rowspan=\"4\"\u003e \u003cp\u003ecommon carp (\u003cem\u003eCyprinus carpio\u003c/em\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e23.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e145.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e25\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e227.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e369\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e22.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e138.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e25.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e215.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e29\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e357.6\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e22.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e134.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e26.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e236.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e365.3\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e22\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e134.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e26\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e229\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e30.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e366\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"3\" rowspan=\"4\"\u003e \u003cp\u003eCatfish\u003c/p\u003e \u003cp\u003e(\u003cem\u003eClarias gariepinus\u003c/em\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e28\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e173.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e34\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e301.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e40\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e407.7\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e29\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e249.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e33\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e291.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e38\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e382.8\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e28.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e201.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e33\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e290\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e37\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e390.6\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e29\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e253.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e32\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e287.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e37.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e396.2\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"3\" rowspan=\"4\"\u003e \u003cp\u003eNile Tilapia (\u003cem\u003eOreochromis niloticus)\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e15\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e58.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e18\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e106.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e25\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e201.4\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e14.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e57.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e17.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e100.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e23\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e198.6\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e13.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e56.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e18\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e112.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e22\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e191.6\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e14.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e57.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e17.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e103.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e24\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e200.5\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"3\" rowspan=\"4\"\u003e \u003cp\u003eCrucian carp\u003c/p\u003e \u003cp\u003e\u003cem\u003e(Carassius Carassius)\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e19\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e186.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e23.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e247.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e26\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e260.9\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e19\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e181.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e24\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e250.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e26\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e265.3\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e20\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e192.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e24\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e251.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e27\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e268.7\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e19.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e183.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e23.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e249.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e26.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e267.3\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eSample Extraction and Analysis\u003c/p\u003e \u003cp\u003eThe fish samples were extracted at the Ethiopian Food and Drug Authority (EFDA) laboratory. The samples were extracted using a pressurized liquid extraction technique of Buchi Speed Extractor E-916 fitted with 40 mL stainless steel cells. The cell was utilized by fitting with the two cellulose filters. About 5 g of each composited sample was mixed with 5 g of diatomaceous earth and loaded into 40 mL extraction cells to perform the extraction process in duplicate. The extraction process was undertaken in three cycles.\u003c/p\u003e \u003cp\u003eThe analytes were recovered with a mixture of n-hexane/dichloromethane (50:50) in three static extraction cycles of 10 min each, at 100 \u003csup\u003eo\u003c/sup\u003eC and 100 bar. The total flush time of the cell with solvent and gas were 2 min and 5 min, respectively. The raw extracts were collected in 240 mL vials and evaporated using a Buchi R-300 rotary evaporator. The dried extract was dissolved using hexane and transferred to test tubes to reduce the volume to about 2 mL using a gentle stream of nitrogen in an organomation OA-HEAT concentrator. The samples were then cleaned up using an active 1 g Florisil column (Florisil cleanup, EPA 3620B method) and finally, the volume was made into 10 mL volumetric flasks for quantification. A list of pesticides targeted for analysis was identified by surveying those widely applied by farmers surrounding Lake Ziway and by reviewing previous research works. Hence, the OCPs, OPPs, and CMs that were investigated are listed with their properties in Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eList of investigated pesticides\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"3\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePesticides\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003eFormula\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eAldrin\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eC\u003csub\u003e12\u003c/sub\u003eH\u003csub\u003e8\u003c/sub\u003eCl\u003csub\u003e6\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eDieldrin\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eC\u003csub\u003e12\u003c/sub\u003eH\u003csub\u003e8\u003c/sub\u003eCl\u003csub\u003e6\u003c/sub\u003eO\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eCis-chlordane\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eC\u003csub\u003e10\u003c/sub\u003eH\u003csub\u003e6\u003c/sub\u003eCl\u003csub\u003e8\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003etrans-Chlordane\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eC\u003csub\u003e10\u003c/sub\u003eH\u003csub\u003e6\u003c/sub\u003eCl\u003csub\u003e8\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003e\u003cem\u003ep,p\u0026rsquo;-\u003c/em\u003eDDT\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eC\u003csub\u003e14\u003c/sub\u003eH\u003csub\u003e9\u003c/sub\u003eCl\u003csub\u003e5\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003e\u003cem\u003ep,p\u0026rsquo;-\u003c/em\u003eDDE\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eC\u003csub\u003e14\u003c/sub\u003eH\u003csub\u003e8\u003c/sub\u003eCl\u003csub\u003e4\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003e\u003cem\u003ep,p\u0026rsquo;-\u003c/em\u003eDDD\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eC\u003csub\u003e14\u003c/sub\u003eH\u003csub\u003e10\u003c/sub\u003eCl\u003csub\u003e4\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eEndosulfan-α\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eC\u003csub\u003e9\u003c/sub\u003eH\u003csub\u003e6\u003c/sub\u003eC\u003csub\u003el6\u003c/sub\u003eO\u003csub\u003e3\u003c/sub\u003eS\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eEndosulfan-sulfate\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eC\u003csub\u003e9\u003c/sub\u003eH\u003csub\u003e6\u003c/sub\u003eCl\u003csub\u003e6\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003eS\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eHeptachlor\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eC\u003csub\u003e10\u003c/sub\u003eH\u003csub\u003e5\u003c/sub\u003eCl\u003csub\u003e7\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eHeptachlor-epoxide\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eC\u003csub\u003e10\u003c/sub\u003eH\u003csub\u003e5\u003c/sub\u003eCl\u003csub\u003e7\u003c/sub\u003eO\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eHexachlorobenzene (HCB)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eC\u003csub\u003e6\u003c/sub\u003eCl\u003csub\u003e6\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eα-HCH\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eC\u003csub\u003e6\u003c/sub\u003eH\u003csub\u003e6\u003c/sub\u003eCl\u003csub\u003e6\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eβ-HCH\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eC\u003csub\u003e6\u003c/sub\u003eH\u003csub\u003e6\u003c/sub\u003eCl\u003csub\u003e6\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eLindane (γ-HCH)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eC\u003csub\u003e6\u003c/sub\u003eH\u003csub\u003e6\u003c/sub\u003eCl\u003csub\u003e6\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eMethoxychlor\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eC\u003csub\u003e16\u003c/sub\u003eH\u003csub\u003e15\u003c/sub\u003eCl\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e2\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eChlorpyrifos- methyl\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eC\u003csub\u003e7\u003c/sub\u003eH\u003csub\u003e7\u003c/sub\u003eCl\u003csub\u003e3\u003c/sub\u003eNO\u003csub\u003e3\u003c/sub\u003ePS\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eChlorpyrifos\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eC\u003csub\u003e9\u003c/sub\u003eH\u003csub\u003e11\u003c/sub\u003eCl\u003csub\u003e3\u003c/sub\u003eNO\u003csub\u003e3\u003c/sub\u003ePS\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eDiazinon\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eC\u003csub\u003e12\u003c/sub\u003eH\u003csub\u003e21\u003c/sub\u003eN\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e3\u003c/sub\u003ePS\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eProfenofos\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eC\u003csub\u003e11\u003c/sub\u003eH\u003csub\u003e15\u003c/sub\u003eBrClO\u003csub\u003e3\u003c/sub\u003ePS\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003ePropoxur\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eC\u003csub\u003e11\u003c/sub\u003eH\u003csub\u003e19\u003c/sub\u003eNO\u003csub\u003e3\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eBendiocarb\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eC\u003csub\u003e11\u003c/sub\u003eH\u003csub\u003e13\u003c/sub\u003eNO\u003csub\u003e4\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eAll targeted pesticides were analyzed using 7890B model Agilent gas chromatography coupled to a 7000D model triple quadrupole mass spectrometer detector (GCMSMS). HP-5ms capillary column having a dimension of 30 m\u0026times;0.25 mm i.d.\u0026times;0.25-\u0026micro;m film thickness was used. Helium was used as a carrier gas with a constant flow rate of 1 mL min\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e. 1 \u0026micro;L of the samples were injected in a splitless mode to split splitless inlet at a temperature of 280\u0026deg;C. Starting from 60\u0026deg;C and holding for 1 min, the oven temperature was risen to 170\u0026deg;C at the rate of 40\u0026deg;C min\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e and to 250\u0026deg;C at the rate of 5\u0026deg;C min\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e and finally to 300\u0026deg;C by 10\u0026deg;C min\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e to hold for 3 min. The transfer line temperature was kept at 280\u0026deg;C.\u003c/p\u003e \u003cp\u003eThe triple quadrupole mass spectrometer was equipped with an EI source operated at 70 eV. The temperature of the MS ion source was set at 230\u0026deg;C and both quadrupole temperatures were kept at 150\u0026deg;C. Helium and nitrogen were used as quenching and collision gases with a flow rate of 2.25 mLmin\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e and 1.5 mLmin\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e, respectively. The Agilent MRM database was used for data acquisition; for each analyte, three MRM transitions were acquired, and two of them were used as confirmatory using their qualifier ratio. Quantification of residual pesticides was performed in duplicate against external reference standards using Agilent quantitative software version 10.0.\u003c/p\u003e \u003cp\u003eLaboratory Quality Control\u003c/p\u003e \u003cp\u003eThe quality of results was ensured with duplicate measurements and recovery analysis. The average recoveries of the spiked standards were 60\u0026ndash;120% for most compounds, except for dieldrin (51.33%) and bendiocarb (121.86%). Quantitatively, the pesticide residue was determined by an external standard method using Sigma Aldrich analytical grade chemicals and reagents. The calibration curves were drawn by injecting eight different concentrations of the pesticide standards. Correlation coefficient (\u003cem\u003er\u003c/em\u003e\u003csup\u003e\u003cem\u003e2\u003c/em\u003e\u003c/sup\u003e) values obtained from calibration curves were \u0026gt;\u0026thinsp;0.993 in all cases. A signal-to-noise ratio-based calculation of the limit of detections (LOD) and limit of quantifications (LOQ) were also performed for each pesticide detection (Wenzl et al., \u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e2016\u003c/span\u003e). The LODs were confirmed by the concentrations of analytes whose signal-to-noise (S/N) ratio was three and ranged from 0.010 to 0.034 \u0026micro;g kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e in the fish samples. Those samples with concentrations detected less than LODs were treated as not detected (n.d.). A single standard was tested every 10 samples throughout the whole procedure to ensure that the system was repeatable and free of any carryover. Identification of the pesticides was done based on the retention time and qualifier to quantifier ratio of ions peak area while quantification was done by using quantifier ion peak area.\u003c/p\u003e \u003cp\u003eHuman Health Risk Assessment\u003c/p\u003e \u003cp\u003eDietary exposure assessment\u003c/p\u003e \u003cp\u003e Pesticide health risks associated with daily exposure were evaluated using the USEPA's guidelines. Estimated daily intake (EDI) was calculated at a daily consumption level of 0.027 kg per day\u003csup\u003e\u0026minus;\u003c/sup\u003e based on FAO data (FAO, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e2011\u003c/span\u003e). The average body weight of an Ethiopian adult used for the calculation was 60 kg as obtained from FAO (FAO, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e2011\u003c/span\u003e). According to \u003cem\u003eEq.\u0026nbsp;1\u003c/em\u003e, dietary exposure to the specific residue of contaminated fish is assessed by calculating the EDI based on average pesticide concentrations measured in each fish species (Joseph et al., \u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e2021\u003c/span\u003e; Tekin \u0026amp; Pazi, 2017; Witczak et al., 2021).\u003cdiv id=\"Equa\" class=\"Equation\"\u003e\u003cdiv format=\"TEX\" class=\"mathdisplay\" id=\"FileID_Equa\" name=\"EquationSource\"\u003e\n$$\\:EDI\\:(\\left(\\frac{mg}{kg}\\right)\\times\\:da{y}^{-\\:})=\\frac{C\\times\\:CR}{BW}\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:(Eq.\\:1)$$\u003c/div\u003e\u003c/div\u003e\u003c/p\u003e \u003cp\u003eWhere C is the average concentration of pesticide measured in fish (mg kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e), CR is the average daily fish consumption rate (kg day\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e), and BW is the assumed average body weight (kg).\u003c/p\u003e \u003cp\u003eRisk characterization\u003c/p\u003e \u003cp\u003eThe calculated daily consumption was compared to the recommended reference doses (RfD) to assess for non-carcinogenic effects. The Reference Dose is an estimate of daily exposure to the human population that is probably not associated with a significant lifetime risk of harmful effects, with uncertainty ranging maybe an order of magnitude(USEPA, \u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e2000a\u003c/span\u003e). The Hazard Quotient was determined by \u003cem\u003eEq.\u0026nbsp;2\u003c/em\u003e. When the Hazard Quotient (HQ)\u0026thinsp;\u0026lt;\u0026thinsp;1, the risk is considered acceptable, and when the HQ\u0026thinsp;\u0026gt;\u0026thinsp;1, it is not acceptable.\u003cdiv id=\"Equb\" class=\"Equation\"\u003e\u003cdiv format=\"TEX\" class=\"mathdisplay\" id=\"FileID_Equb\" name=\"EquationSource\"\u003e\n$$\\:HQ=\\frac{EDI}{ARfD}\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:(Eq.2)$$\u003c/div\u003e\u003c/div\u003e\u003c/p\u003e \u003cp\u003eEstimates of carcinogenic risk are expressed as the likelihood that a person would develop cancer throughout a lifetime of being exposed to pesticide residue. \u003cem\u003eEq.\u0026nbsp;3\u003c/em\u003e was used to determine the hazard ratio (HR) for the carcinogenic risk assessment (Dougherty et al., \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e2000\u003c/span\u003e).\u003cdiv id=\"Equc\" class=\"Equation\"\u003e\u003cdiv format=\"TEX\" class=\"mathdisplay\" id=\"FileID_Equc\" name=\"EquationSource\"\u003e\n$$\\:HR=\\frac{EDI}{CBC}\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:(Eq.3)$$\u003c/div\u003e\u003c/div\u003e\u003c/p\u003e \u003cp\u003eWhere CBC is the cancer benchmark concentration. The formula CBC for carcinogenic impact was determined by setting the risk of lifetime exposure to the pesticide residue at 1 in 1,000,000:\u003cdiv id=\"Equd\" class=\"Equation\"\u003e\u003cdiv format=\"TEX\" class=\"mathdisplay\" id=\"FileID_Equd\" name=\"EquationSource\"\u003e\n$$\\:CB=\\frac{RL\\times\\:BW}{CR\\times\\:OSF}\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:(Eq.4)$$\u003c/div\u003e\u003c/div\u003e\u003c/p\u003e \u003cp\u003eWhere, RL is the highest tolerable risk level (1 \u0026times; 10\u003csup\u003e\u0026minus;\u0026thinsp;6\u003c/sup\u003e) and OSF stands for oral slope factor (mg/kg/d), CR for fish consumption rate (g/day), and BW for body weight (kg) (USEPA, \u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e2000a\u003c/span\u003e). Oral slope factor values were obtained from the USEPA\u0026rsquo;s integrated risk information system (IRIS) (USEPA, \u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e2000a\u003c/span\u003e). As of USEPA (\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e2000a\u003c/span\u003e), a risk level below 10\u003csup\u003e\u0026minus;\u0026thinsp;6\u003c/sup\u003e (acceptable), between 10\u003csup\u003e\u0026minus;\u0026thinsp;6\u003c/sup\u003e and 10\u003csup\u003e\u0026minus;\u0026thinsp;4\u003c/sup\u003e (considered) is found in an area of concern, and RL greater than 10\u003csup\u003e\u0026minus;\u0026thinsp;4\u003c/sup\u003e (high cancer risk) (Dougherty et al., \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e2000\u003c/span\u003e). With this definition, an HR\u0026thinsp;\u003cspan type=\"Underline\" class=\"Underline\" name=\"Emphasis\"\u003e\u0026ge;\u003c/span\u003e\u0026thinsp;1 implies a risk level of one in a million-lifetime, showing a potential risk to human health (Dougherty et al., \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e2000\u003c/span\u003e). The health risk assessment was conducted on six parameters; ΣDDT was the sum of \u003cem\u003ep,p\u0026rsquo;\u003c/em\u003e-DDT, \u003cem\u003ep,p\u0026rsquo;\u003c/em\u003e-DDD, \u003cem\u003ep,p\u0026rsquo;\u003c/em\u003e-DDE; HCH, Hexachlorobenzene; Σheptachlor was the sum of heptachlor and heptachlor epoxide; diazinon and chlorpyrifos.\u003c/p\u003e \u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eData analysis\u003c/h2\u003e \u003cp\u003eDescriptive statistical analysis was conducted with SPSS version 26. The mean values of each pesticide concentration in the fish species were compared using a one-way ANOVA. To determine the association between fish size and POP concentrations, POP concentrations (\u0026micro;g kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e) were regressed against total fish length, weight, and fish species as a categorical variable. Microsoft Excel is used for calculations to determine the health risk of the consumption of pesticide-contaminated fish and their compliance with international regulations and European Union MRL values.\u003c/p\u003e \u003c/div\u003e"},{"header":"Results and Discussion","content":"\u003cp\u003ePesticide Concentrations in Fish Samples\u003c/p\u003e \u003cp\u003eThe present study designated 22 compounds belonging to OCP, OPPs, and Carbamates in the four fish species. The chromatographs below (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e and Fig.\u0026nbsp;3) are selected to show the chromatograms detected using the GCMS triple quadrupole technique. All chromatogram results of the samples, standards, calibration curves, and their response are attached in Appendices.\u003c/p\u003e \u003cp\u003eThe results of all pesticide concentrations are summarized as arithmetic averages in (\u0026micro;g kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e) in Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e. The analysis revealed the presence of 45% of the pesticides and the remaining 55% were not found above the limit of detection in any sample analyzed. As listed in Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e, α -HCH, HCB, Heptachlor, heptachlor epoxide, \u003cem\u003ep,p\u0026rsquo;-\u003c/em\u003eDDD, \u003cem\u003ep,p\u0026rsquo;\u003c/em\u003e-DDT, \u003cem\u003ep,p\u0026rsquo;-\u003c/em\u003eDDE, chlorpyrifos, propoxur, diazinon were detected while β-HCH, γ-HCH, aldrin, dieldrin, endosulfan I, endosulfan sulfate, bendiocarb, profenofos, chlordane-trans, chlordane-cis, methoxychlor, chlorpyrifos-methyl are pesticides existed in less than detection limit (Appendix 4). According to the European Union guidelines for maximum residue levels (MRL) of pesticides, the analysis of pesticide residues in the samples revealed that DDTs, diazinon, and propoxur were found to have levels higher than the MRL (EU, \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e2005\u003c/span\u003e). However, other positively detected pesticides were found to be below the MRL threshold.\u003c/p\u003e \u003cp\u003eLevels of OCPs\u003c/p\u003e \u003cp\u003eThe concentrations of OCPs ranged from 12.77 to 163.93 \u0026micro;g/kg, with a mean concentration of 65.45 \u0026micro;g kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e. The \u003cem\u003ep,p\u0026rsquo;\u003c/em\u003e-DDT, \u003cem\u003ep,p\u0026rsquo;-\u003c/em\u003eDDE, \u003cem\u003ep,p\u0026rsquo;-\u003c/em\u003eDDD, HCB, α -HCH, and heptachlor were found in every sample. The concentration of DDTs existed ranges from 12.33\u0026ndash;162.40 \u0026micro;g kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e. Other pesticides detected in all fish species were hexachlorobenzene (HCB) at concentrations up to 1.13 \u0026micro;g kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e, heptachlor at concentrations from 0.1 \u0026micro;g kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e up to 0.97 \u0026micro;g kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e and α -HCH found up to 0.1\u0026micro;g/kg (Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e). Heptachlor epoxide was found in only catfish species at concentrations up to 0.02 \u0026micro;g/kg. Fish samples found in this investigation often showed an OCP contamination pattern that was DDTs\u0026thinsp;\u0026gt;\u0026thinsp;HPTs\u0026thinsp;\u0026gt;\u0026thinsp;HCB\u0026thinsp;\u0026gt;\u0026thinsp;HCHs. This finding suggests that the biota around the Lake has been exposed to a high level of DDTs. DDTs level in another Ethiopian lake are likewise significantly higher than those of other POPs. The mean concentration of DDTs in Lake Koka was reported ten times higher than that of other POPs (Deribe et al., 2011). Similarly, it has been reported that the biota in Lake Malawi has been exposed to DDT concentrations up to 60 times greater than those of other organochlorine pesticides (Kidd et al., 2001).\u003c/p\u003e \u003cp\u003eDDTs\u003c/p\u003e \u003cp\u003eDDTs were the most often found and predominated in all samples of the OCPs examined. The concentration ranges from (12.33 to 162.40 \u0026micro;g kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e) and accounts for 97.97% of the total OCPs. Within the DDT series, \u003cem\u003ep,p\u0026rsquo;-\u003c/em\u003eDDE, the most stable isomer, found at the highest concentrations from 10.75 \u0026micro;g kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e up to 148.9 \u0026micro;g kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e accounted for 84.97% of the total DDTs, an indication of non-recent exposure. The other DDT constituent was \u003cem\u003ep,p\u0026rsquo;-\u003c/em\u003eDDD, which was found in all of these samples at concentrations up to 8.05 \u0026micro;g kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e (Table\u0026nbsp;\u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e4\u003c/span\u003e). The \u003cem\u003ep,p\u0026rsquo;-\u003c/em\u003eDDT ranges from ( 1.25 to 8.96 \u0026micro;g kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e) to account for 7.39% of the total OCPs. The proportions of the metabolites (\u003cem\u003ep,p\u0026rsquo;\u003c/em\u003e-DDD and \u003cem\u003ep,p\u0026rsquo;\u003c/em\u003e-DDE) indicated that aerobic degradation was the dominant degradation pathway as the concentrations of \u003cem\u003ep,p\u0026rsquo;-\u003c/em\u003eDDE were greater than the concentrations of \u003cem\u003ep,p\u0026rsquo;-\u003c/em\u003eDDD in all the fish samples. These metabolites are formed by aerobic degradation and anaerobic degradation, respectively, in the environment and organisms (Mahugija et al., \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e2018\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eAs summarized in Table\u0026nbsp;\u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e4\u003c/span\u003e, the highest mean concentration of \u003cem\u003ep,p\u0026rsquo;-\u003c/em\u003eDDE and \u003cem\u003ep,p\u0026rsquo;-\u003c/em\u003eDDD isomers were detected in catfish as 148.9 \u0026micro;g/kg and 8.05 \u0026micro;g/kg, respectively; these differed significantly (p\u0026thinsp;\u0026lt;\u0026thinsp;0.05) compared with the \u003cem\u003ep,p\u0026rsquo;-\u003c/em\u003eDDE and \u003cem\u003ep,p\u0026rsquo;-\u003c/em\u003eDDD content of other fish species. The lowest concentrations of \u003cem\u003ep,p\u0026rsquo;-\u003c/em\u003eDDE and \u003cem\u003ep,p\u0026rsquo;-\u003c/em\u003eDDD were found in Nile Tilapia 10.75 \u0026micro;g kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e and 0.33 \u0026micro;g kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e, respectively (Table\u0026nbsp;\u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e4\u003c/span\u003e). Whereas, the highest concentration of \u003cem\u003ep,p\u0026rsquo;-\u003c/em\u003eDDT is found in Cyprinus carpio and the lowest is in the Nile Tilapia fish species (P\u0026thinsp;\u0026lt;\u0026thinsp;0.01). The ratios of \u003cem\u003ep,p\u0026rsquo;-\u003c/em\u003eDDE and \u003cem\u003ep,p\u0026rsquo;-\u003c/em\u003eDDT in Nile Tilapia, Carassius Carassius, Cyprinus carpio, and Catfish were 8.6, 8.67, 2.93, and 27.32, respectively. The DDE to DDT ratio is a useful tool for assessing DDT degradation and evaluating the current use of DDT in a specific environment (Strandberg \u0026amp; Hites, \u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e2001\u003c/span\u003e). Observed mean values of \u003cem\u003ep,p'-\u003c/em\u003eDDE to \u003cem\u003ep,p'-\u003c/em\u003eDDT ratios greater than 1 in the case of all the four fish species suggests that there is long-term bio-transformation of DDT and fish species have experienced almost no recent exposure to DDT (Strandberg and Hites, \u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e2001\u003c/span\u003e). This finding is supported by a study conducted by Mergia et al. (\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e2021\u003c/span\u003e), which also found no recent exposure to DDT in fish species in Lake Ziway. However, another recent study conducted by Habtamu (\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e2020\u003c/span\u003e), revealed the presence of recent application of DDT in the Lake Ziway catchment area.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eList of target pesticides analyzed and its concentration\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"7\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTarget Analyte\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eRange (\u0026micro;g kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eMinimum (\u0026micro;g kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eMaximum (\u0026micro;g kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eSum (\u0026micro;g kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eMean (\u0026micro;g kg\u003csup\u003e\u0026minus;\u0026thinsp;1)\u003c/sup\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003eStd. Deviation\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eα -HCH\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.04\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.06\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.34\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.09\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.02\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHexachlorobenzene\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.23\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e2.57\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.64\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.37\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eβ-HCH\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eLindane\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHeptachlor\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.87\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.97\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e2.07\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.52\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.36\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHeptachlor epoxide\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.02\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.02\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.04\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.01\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.01\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAldrin\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDieldrin\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eChlordane, trans\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eChlordane, cis\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.08\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.15\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eEndosulfan_ I\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eEndosulfan sulphate\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003ep,p\u0026rsquo;-\u003c/em\u003eDDE\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e138.15\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e10.75\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e148.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e217.95\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e54.49\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e63.58\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003ep,p\u0026rsquo;-\u003c/em\u003eDDD\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e7.72\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.33\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e8.05\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e19.17\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e4.79\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e3.28\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003ep,p\u0026rsquo;-\u003c/em\u003eDDT\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e7.71\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.25\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e8.96\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e19.36\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e4.84\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e3.24\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMethoxychlor\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eChlorpyrifos\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e5.46\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.42\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e5.88\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e7.75\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.94\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e2.63\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eChlorpyrifos_ methyl\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDiazinon\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e10.09\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2.46\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e12.55\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e33.72\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e8.43\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e4.26\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePropoxur\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e62.47\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3.82\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e66.29\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e141.87\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e35.47\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e25.55\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBendiocarb\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eProfenofos\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u0026sum;Heptachlor\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.85\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.12\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.97\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e2.11\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.53\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.35\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u0026sum;DDT\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e150.07\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e12.33\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e162.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e256.48\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e64.12\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e66.89\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u0026sum;OCP\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e151.16\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e12.77\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e163.93\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e261.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e65.45\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e67.14\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFish Length (cm)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e14.66\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e18.59\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e33.25\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e101.11\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e25.28\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e6.15\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFish weight (g)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e181.88\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e120.37\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e302.25\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e899.71\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e224.93\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e76\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eAmong the four fish species studied, the highest mean concentration of DDTs residues was noted in the Catfish, while the lowest was in the Nile Tilapia (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05). The concertation of DDTs in fish species found as Catfish\u0026thinsp;\u0026gt;\u0026thinsp;Cyprinus carpio\u0026thinsp;\u0026gt;\u0026thinsp;Carassius Carassius\u0026thinsp;\u0026gt;\u0026thinsp;Nile Tilapia clearly shows the biomagnification of DDTs in high trophic levels which can be known unanimously based on their feeding habit and biomagnification factor study done by (Mergia et al., \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e2021\u003c/span\u003e). Another study conducted on Lake Hawassa which exists in the same rift valley region also revealed the concentration of DDTs in catfish is higher than the Nile tilapia (Deribe et al., \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e2014\u003c/span\u003e). In another country, a study conducted in Egypt reported there is a higher rate of pesticide accumulation in catfish (C.gariepinus) compared to Nile tilapia (O. niloticus) from the same location (Yahia \u0026amp; Elsharkawy, \u003cspan citationid=\"CR34\" class=\"CitationRef\"\u003e2014\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab4\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 4\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eConcentration of pesticides in fish species\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"5\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eTarget Analyte\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"4\" nameend=\"c5\" namest=\"c2\"\u003e \u003cp\u003eMean concentration (\u0026micro;g/kg)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNile Tilapia\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eCarassius carassius\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eCyprinus \u003c/p\u003e \u003cp\u003ecarpio\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eCatfish\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHexachlorobenzene\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.23\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.61\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.6\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAlpha-lindane (α -HCH)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.09\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.06\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.09\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBeta lindane (β-HCH)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGamma (Lindane)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHeptachlor\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.46\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.97\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.54\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHeptachlor_epoxide\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.02\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.02\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAldrin\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDieldrin\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eChlordane_trans\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eChlordane_cis\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.3\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eEndosulfan_I\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eEndosulfan_sulfate\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003ep,p\u0026rsquo;-\u003c/em\u003eDDE\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e10.75\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e32.08\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e26.22\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e148.9\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003ep,p\u0026rsquo;-\u003c/em\u003eDDD\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.33\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e6.09\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e8.05\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003ep,p\u0026rsquo;-\u003c/em\u003eDDT\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.25\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e8.96\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e5.45\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMethoxychlor\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eChlorpyrifos\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.42\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.81\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.64\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e5.88\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eChlorpyrifos_methyl\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDiazinon\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2.46\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e9.41\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e9.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e12.55\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePropoxur\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e3.82\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e34.18\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e66.29\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e37.58\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBendiocarb\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eProfenofos\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003en.d.\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u0026sum;Heptachlor\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.12\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.48\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.97\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.54\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u0026sum;DDT\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e12.33\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e40.48\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e41.27\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e162.4\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u0026sum;OCP\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e12.77\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e42.19\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e42.91\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e163.93\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFish Length (cm)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e18.59\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e23.18\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e26.08\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e33.25\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFish weight (g)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e120.37\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e233.83\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e243.27\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e302.25\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eHCHs\u003c/p\u003e\u003cp\u003eFrom the isomers of HCH, only α -HCH is detected in fish species; whereas the remaining β-HCH, γ-HCH isomers are less than the detection limit in all fish species. HCHs accounted for 0.1% of the total OCPs measured. There are no statistically significant differences (p\u0026thinsp;\u0026gt;\u0026thinsp;0.05) in the content of HCH isomer in all four fish species. Based on the finding, it can be inferred that the nonexistence of γ-HCH (lindane) concentrations in the samples indicates that there is no current usage of lindane around the Lake. Results of other researchers revealed conflicting trends; for instance, Mergia et al. (\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e2021\u003c/span\u003e), suggested all HCHs are not detected, whereas the results from Yohannes et al. (\u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e2014\u003c/span\u003e), revealed all are significantly positive results in all fish species.\u003c/p\u003e \u003cp\u003eHCB, HPTs, CHLs and Other OCPs\u003c/p\u003e \u003cp\u003eHCB accounted for 0.8% of the total OCPs measured in the studied fish species. HPTs (the sum of heptachlor and heptachlor epoxide) were present in all of the fish species with no significant differences in amount (p\u0026thinsp;\u0026gt;\u0026thinsp;0.05) in all four fish species. Cis chlordane (CHL) is above the detection limit only in catfish. The remaining investigated OCPs, which include dieldrin and aldrin, trans chlordane, α-endosulfan, endosulfan sulfate, and methoxychlor, are presumably less than the detection limit in all fish species probably due to the prohibition of their usage. Similar to the above comparisons, these results are still conflicting with previous studies on the Lake; Mergia et al. (\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e2021\u003c/span\u003e), suggested all HCB, HPTs, CHLs, dieldrin and aldrin, trans chlordane, α-endosulfan, endosulfan sulfate, and methoxychlor are less than the detection limit. However, HCB, HPTs, and CHLs are positive according to (Yohannes et al., \u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e2014\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eLevels of OPPs\u003c/p\u003e \u003cp\u003eOrganophosphate pesticides tested were only diazinon, chlorpyrifos and chlorpyrifos-methyl. Chlorpyrifos methyl was less than the detection limit, while diazinon and chlorpyrifos were detected in all fish species. Diazinon concentration ranges from 2.46 to 12.55 \u0026micro;g/kg and accounted for 7.58% of the total pesticides; whereas, chlorpyrifos concentration varied from 0.42 to 5.88 \u0026micro;g/kg and made up only 1.74% of the total pesticide. In catfish, mean values of 5.88 and 12.55 \u0026micro;g/kg chlorpyrifos and diazinon were respectively detected to be significantly differing from other fish species (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05). The only previous study conducted by Mergia et al. revealed diazinon and chlorpyrifos are found to be less than the detection limit (Mergia et al., \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e2021\u003c/span\u003e). However, as support of the current research, diazinon and chlorpyrifos are the types of OPPs registered in Ethiopia and are frequently utilized by small-scale vegetable producers primarily on cabbage, onion, and tomato along the littoral region of the Lake (Mengistie et al., 2017).\u003c/p\u003e \u003cp\u003eLevel of Carbamates\u003c/p\u003e \u003cp\u003eBased on the findings, propoxur was detected in all fish species, with concentrations ranging from 3.82 to 66.29 \u0026micro;g/kg. It constituted 31.87% of all persistent organic pollutants (POPs) that were examined. The amount of propoxur detected in Cyprinus carpio (common carp), 66.29 \u0026micro;g/kg was significantly different from other species (p\u0026thinsp;\u0026lt;\u0026thinsp;0.05). The content of propoxur was lowest in Nile tilapia and greatest in Cyprinus carpio fish species. No research has been conducted on carbamates in Lake Ziway including propoxur and bendiocarb, to compare for additional information.\u003c/p\u003e \u003cp\u003eRelation of Fish Size with Pesticides Accumulation\u003c/p\u003e \u003cp\u003eExcept for a single value of chlorpyrifos, all pesticides were progressively increasing in concentrations within \u003cem\u003eC. gariepinus\u003c/em\u003e fish species of different sizes. The length and weight distribution of analyzed \u003cem\u003eNile Tilapia\u003c/em\u003e, \u003cem\u003ecarassius carassius\u003c/em\u003e, and \u003cem\u003ecyprinus carpio\u003c/em\u003e were very narrow primarily due to the small size of individuals. Thus, the concentration of pesticides within these species did not rise noticeably with size.\u003c/p\u003e \u003cp\u003eBased on this study, it appears that length and weight increased along with each other for all individuals of the studied fish species with a positive and strong correlation of R\u003csup\u003e2\u003c/sup\u003e value, 0.877, and a \u003cem\u003ep\u003c/em\u003e-value of 0.064. The findings of Yohannes et al. (\u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e2014\u003c/span\u003e) and Zhang et al. (2013) also revealed similar correlations between length and weight in fish species. As indicated in Table\u0026nbsp;\u003cspan refid=\"Tab5\" class=\"InternalRef\"\u003e5\u003c/span\u003e, the length and weight of the studied fish species varied within the range of 18.59 cm to 33.25 cm and 120.37 g to 302.25 g, respectively. With all data composited for the four fish species, DDTs, chlorpyrifos, and diazinon were progressively increased with the fish size. As the R\u003csup\u003e2\u003c/sup\u003e value in Table\u0026nbsp;\u003cspan refid=\"Tab5\" class=\"InternalRef\"\u003e5\u003c/span\u003e indicates, the mean concentration of \u003cem\u003ep,p\u0026rsquo;-\u003c/em\u003eDDE, \u003cem\u003ep,p\u0026rsquo;-\u003c/em\u003eDDD, diazinon, chlorpyrifos, and chlordane-cis show a positive correlation with the size of all fish species. The increase in the concentration of DDT metabolites, such as \u003cem\u003ep,p'-\u003c/em\u003eDDE and \u003cem\u003ep,p'-\u003c/em\u003eDDD, suggests that the biomagnification of hydrophobic organic compounds is dependent on metabolism capacity and octanol-water partition coefficients (Kow) (Zhang et al., 2013).\u003c/p\u003e \u003cp\u003eHowever, no significant correlation was found between the size of the fishes (length or weight) and concentration of \u003cem\u003ep,p\u0026rsquo;\u003c/em\u003e-DDT, heptachlor, hexachlorobenhbn mbbbbzene, heptachlor epoxide, α -HCH. The lack of correlation between pesticide concentrations and other factors in fish can be attributed to several reasons. One possible reason is the low concentration of pesticides detected, which may not be consistent enough to establish a strong correlation. Additionally, the decrease in the concentration of \u003cem\u003ep,p\u0026rsquo;\u003c/em\u003e-DDT is likely due to Metabolization. Metabolization refers to the process by which a substance, in this case, \u003cem\u003ep,p\u0026rsquo;-\u003c/em\u003eDDT, is broken down and transformed within an organism. Chemicals that are metabolized and eliminated by organisms normally show low biomagnification potentials (Deribe et al., 2011).le 5\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab5\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 5\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eCorrelation of pesticides and fish size\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"6\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eTarget Analyte\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003e\u003cem\u003eP\u003c/em\u003e-value\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\" morerows=\"1\" rowspan=\"2\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003eR\u003csup\u003e2\u003c/sup\u003e\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eLength (cm)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eWeight (g)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eLength (cm)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eWeight (g)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHexachlorobenzene\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.799\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.483\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.040\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.267\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHCH-alpha\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.859\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.883\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.020\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.014\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHeptachlor\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.475\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.347\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.275\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.426\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHeptachlor epoxide\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.175\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.273\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.680\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.528\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eChlordane-cis\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.135\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.322\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.748\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.460\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDDE\u003cem\u003e-p,p'\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.088\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.230\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.832\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.592\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDDD\u003cem\u003e-p,p'\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.056\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.008\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.892\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.985\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDDT\u003cem\u003e-p,p'\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.422\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.340\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.335\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.436\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eChlorpyrifos\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.116\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.284\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.781\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.512\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDiazinon\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.090\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.003\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.828\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.994\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePropoxur\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.456\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.309\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.295\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.478\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSum of DDT\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.059\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.188\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.886\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.660\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eAs illustrated in Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e4\u003c/span\u003e, the total pesticide concentration is also significantly higher in \u003cem\u003eC. gariepinus\u003c/em\u003e (Catfish). The biomagnification pathway of uptake may be significant for fish in their natural habitats, particularly for benthic-based food webs and highly lipophilic pollutants. Since DDT eventually converts to DDE and DDD, larger individuals of these species most likely accumulate a more degraded form of the pesticide. Lipophilic POPs like DDT can bioaccumulate and biomagnify with increasing trophic levels, larger concentrations of POPs exist in fatty or predatory fish species than small fish at lower trophic levels (Gupta et al., \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e2022\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eAs pointed out by Adegun et al. (\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2020\u003c/span\u003e), length and weight are vital variables for explaining the variation in concentrations of POPs. Therefore, larger fish, which are often the target of commercial and recreational fishing, may pose a greater risk for human consumption due to their higher pesticide content. Additionally, the role of larger fish as predators means that their contamination reflects a broader issue of pesticide magnification throughout the trophic levels of aquatic ecosystems (Sharma et al., \u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e2009\u003c/span\u003e). The health of these ecosystems and the species within them may be compromised by the pervasive presence of pesticides, which can have wide effects on biodiversity.\u003c/p\u003e \u003cp\u003eHuman Health Risk Assessment\u003c/p\u003e \u003cp\u003eEstimation of daily intake (EDI)\u003c/p\u003e \u003cp\u003eFish consumption is one way that contaminants can enter the human body. To determine the possible exposure of humans to persistent organic pollutants (POPs), Estimated Daily Intake (EDI) values are calculated using the average concentration of target contaminants in several fish species. As summarized in Table\u0026nbsp;\u003cspan refid=\"Tab6\" class=\"InternalRef\"\u003e6\u003c/span\u003e, the estimated daily intake (EDI) of DDTs was the highest, while α-HCH had the lowest EDI, aligning with the concentration trends observed in the fish species. The health risk is also attributed to the type of fish in which its pesticide accumulation capacity was observed differently (Table\u0026nbsp;\u003cspan refid=\"Tab7\" class=\"InternalRef\"\u003e7\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab6\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 6\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eHealth risk associated with the daily intake of pesticides\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"8\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTarget Analyte\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMean, Residue level (mg/kg)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eOral RfD (mg/kg/day)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eCancer Slope factor (mg/kg/day)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eCBC (mg/kgbw/d)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eEDI(Adult)\u003c/p\u003e \u003cp\u003e(mg/kgbw/d)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003eNon-carcinogenic Risk (HQ)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c8\"\u003e \u003cp\u003eCancer Risk (HR)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eα -Lindane\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e8.50x10\u003csup\u003e\u0026minus;\u0026thinsp;5\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.008\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e6.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.12x10\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e3.83x10\u003csup\u003e\u0026minus;\u0026thinsp;8\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e4.78x10\u003csup\u003e\u0026minus;\u0026thinsp;6\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e3.41x10\u003csup\u003e\u0026minus;\u0026thinsp;7\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHCB\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e6.43x10\u003csup\u003e\u0026minus;\u0026thinsp;4\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.0008\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e5.84x10\u003csup\u003e\u0026minus;\u0026thinsp;2\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e2.89x10\u003csup\u003e\u0026minus;\u0026thinsp;7\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e3.61x10\u003csup\u003e\u0026minus;\u0026thinsp;4\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e4.95x10\u003csup\u003e\u0026minus;\u0026thinsp;6\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHeptachlors\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e5.28x10\u003csup\u003e\u0026minus;\u0026thinsp;4\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.0005\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e4.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e2.53x10\u003csup\u003e\u0026minus;\u0026thinsp;2\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e2.37x10\u003csup\u003e\u0026minus;\u0026thinsp;7\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e4.75x10\u003csup\u003e\u0026minus;\u0026thinsp;4\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e9.39x10\u003csup\u003e\u0026minus;\u0026thinsp;6\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDDTs\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e6.41x10\u003csup\u003e\u0026minus;\u0026thinsp;2\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.0005\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.34\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e2.75x10\u003csup\u003e\u0026minus;\u0026thinsp;3\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e2.89x10\u003csup\u003e\u0026minus;\u0026thinsp;5\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e5.77x10\u003csup\u003e\u0026minus;\u0026thinsp;2\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e1.05x10\u003csup\u003e\u0026minus;\u0026thinsp;2\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eChlorpyrifos\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.94x10\u003csup\u003e\u0026minus;\u0026thinsp;3\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.0003\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eNA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eNA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e8.72x10\u003csup\u003e\u0026minus;\u0026thinsp;7\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e2.91x10\u003csup\u003e\u0026minus;\u0026thinsp;3\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eNA\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDiazinon\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e8.43x10\u003csup\u003e\u0026minus;\u0026thinsp;3\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.0007\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eNA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eNA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e3.79x10\u003csup\u003e\u0026minus;\u0026thinsp;6\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e5.42x10\u003csup\u003e\u0026minus;\u0026thinsp;3\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eNA\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eNA: data not available in USEPA database.\u003c/p\u003e \u003cp\u003eRisk assessment\u003c/p\u003e \u003cp\u003eNon-carcinogenic risk assessment\u003c/p\u003e \u003cp\u003eTo evaluate the potential noncarcinogenic health risks of consuming persistent organic pollutants (POPs) through diet, the daily intakes were compared to the maximum acceptable daily intake values (reference doses, RfDs) using the standard formula explained (Yu et al., \u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e2012\u003c/span\u003e). As summarized in Table\u0026nbsp;\u003cspan refid=\"Tab6\" class=\"InternalRef\"\u003e6\u003c/span\u003e, the estimated daily intake of all POPs investigated in Ziway Lake is lower than their respective RfD values, indicating that they do not pose a non-carcinogenic health risk. Specifically, α-HCH, despite being present in all fish species, is significantly lower than its RfD value for non-carcinogenic effects. Similarly, a study conducted by Yohannes et al. (\u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e2014\u003c/span\u003e), in the same location also reported no non-carcinogenic health risks associated with these pesticides. Additionally, studies conducted in China have also suggested that fish consumption would not pose a non-cancer risk (Cui et al., \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e2015\u003c/span\u003e; Yu et al., \u003cspan citationid=\"CR36\" class=\"CitationRef\"\u003e2014\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eThe non-carcinogenic risk value (HQ\u0026thinsp;\u0026lt;\u0026thinsp;1) indicates that there is a low risk of adverse health effects from fish consumption. However, it does not assure that there is no probable health risk associated with fish consumption. This study revealed the levels of DDTs and diazinon in all fish species exceeded the EU's recommended MRL threshold. This suggests the pollutants could still accumulate in the human body and potentially cause health concerns. Furthermore, the study did not consider the possibility of synergistic effects when multiple pesticides or pollutants are present simultaneously.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab7\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 7\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eHealth risks based on fish species\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"9\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c9\" colnum=\"9\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e \u003cp\u003eTarget analytes\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"8\" nameend=\"c9\" namest=\"c2\"\u003e \u003cp\u003eFish species\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003e\u003cb\u003eNile Tilapia\u003c/b\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c5\" namest=\"c4\"\u003e \u003cp\u003e\u003cb\u003eC. carassius\u003c/b\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c7\" namest=\"c6\"\u003e \u003cp\u003e\u003cb\u003eCyprinus carpio\u003c/b\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c9\" namest=\"c8\"\u003e \u003cp\u003e\u003cb\u003eCatfish\u003c/b\u003e\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNon-carcinogenic Risk (HQ)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eCancer Risk (HR)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eNon-carcinogenic Risk (HQ)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eCancer Risk (HR)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eNon-carcinogenic Risk (HQ)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003eCancer Risk (HR)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c8\"\u003e \u003cp\u003eNon-carcinogenic Risk (HQ)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c9\"\u003e \u003cp\u003eCancer Risk (HR)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eα -HCH\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e5.06x10\u003csup\u003e\u0026minus;\u0026thinsp;6\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3.83x10\u003csup\u003e\u0026minus;\u0026thinsp;7\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e5.63x10\u003csup\u003e\u0026minus;\u0026thinsp;6\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e4.73x10\u003csup\u003e\u0026minus;\u0026thinsp;7\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e3.38x10\u003csup\u003e\u0026minus;\u0026thinsp;6\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.70x10\u003csup\u003e\u0026minus;\u0026thinsp;7\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e5.06x10\u003csup\u003e\u0026minus;\u0026thinsp;6\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e3.83x10\u003csup\u003e\u0026minus;\u0026thinsp;7\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHCB\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.29x10\u003csup\u003e\u0026minus;\u0026thinsp;4\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e6.35x10\u003csup\u003e\u0026minus;\u0026thinsp;7\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e6.36x10\u003csup\u003e\u0026minus;\u0026thinsp;4\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.53x10\u003csup\u003e\u0026minus;\u0026thinsp;5\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e3.43x10\u003csup\u003e\u0026minus;\u0026thinsp;4\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e4.47x10\u003csup\u003e\u0026minus;\u0026thinsp;6\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e3.38x10\u003csup\u003e\u0026minus;\u0026thinsp;4\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e4.32x10\u003csup\u003e\u0026minus;\u0026thinsp;6\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHPTs\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.08x10\u003csup\u003e\u0026minus;\u0026thinsp;4\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4.86x10\u003csup\u003e\u0026minus;\u0026thinsp;7\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e4.32x10\u003csup\u003e\u0026minus;\u0026thinsp;4\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e7.78x10\u003csup\u003e\u0026minus;\u0026thinsp;6\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e8.73x10\u003csup\u003e\u0026minus;\u0026thinsp;4\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e3.18x10\u003csup\u003e\u0026minus;\u0026thinsp;5\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e4.86x10\u003csup\u003e\u0026minus;\u0026thinsp;4\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e9.84x10\u003csup\u003e\u0026minus;\u0026thinsp;6\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDDTs\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.11x10\u003csup\u003e\u0026minus;\u0026thinsp;2\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3.88x10\u003csup\u003e\u0026minus;\u0026thinsp;4\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3.64x10\u003csup\u003e\u0026minus;\u0026thinsp;2\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e4.18x10\u003csup\u003e\u0026minus;\u0026thinsp;3\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e3.71x10\u003csup\u003e\u0026minus;\u0026thinsp;2\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e4.34x10\u003csup\u003e\u0026minus;\u0026thinsp;3\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e1.46x10\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e6.73x10\u003csup\u003e\u0026minus;\u0026thinsp;2\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eChlorpyrifos\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e6.30x10\u003csup\u003e\u0026minus;\u0026thinsp;4\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eNA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.22x10\u003csup\u003e\u0026minus;\u0026thinsp;3\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eNA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e9.60x10\u003csup\u003e\u0026minus;\u0026thinsp;4\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eNA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e8.82x10\u003csup\u003e\u0026minus;\u0026thinsp;3\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eNA\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDiazinon\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.58x10\u003csup\u003e\u0026minus;\u0026thinsp;3\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eNA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e6.05x10\u003csup\u003e\u0026minus;\u0026thinsp;3\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eNA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e5.98x10\u003csup\u003e\u0026minus;\u0026thinsp;3\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eNA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e8.07x10\u003csup\u003e\u0026minus;\u0026thinsp;3\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eNA\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e\u003cp\u003eCarcinogenic risk assessment\u003c/p\u003e \u003cp\u003eThis risk assessment was conducted to assess the carcinogenic effects of OCPs by using cancer risk estimates and HRs. The analysis in Tables\u0026nbsp;\u003cspan refid=\"Tab6\" class=\"InternalRef\"\u003e6\u003c/span\u003e and \u003cspan refid=\"Tab7\" class=\"InternalRef\"\u003e7\u003c/span\u003e showed that fish consumption linked to α-HCH, HCB, and HPTs contamination posed a negligible cancer risk, with the calculated risks being almost less than 1x10\u003csup\u003e\u0026minus;\u0026thinsp;6\u003c/sup\u003e, indicating low concern. However, the cancer risk associated with DDTs exceeded 1x10\u003csup\u003e\u0026minus;\u0026thinsp;4\u003c/sup\u003e in all fish species, indicating that the potential risk from consuming fish contaminated with DDTs should not be ignored. It is crucial to acknowledge these findings and consider further research and measures to mitigate the risks and ensure the safety of our food sources.\u003c/p\u003e \u003cp\u003eThe levels of cancer risk exposure to DDTs varied across fish species, ranging from 3.88x10\u003csup\u003e\u0026minus;\u0026thinsp;4\u003c/sup\u003e in O. niloticus to 6.73x10\u003csup\u003e\u0026minus;\u0026thinsp;2\u003c/sup\u003e in \u003cem\u003eC. gariepinus\u003c/em\u003e. This suggests that an adult human being would have a chance of approximately 4 in 10,000 to 7 in 100 of developing cancer from DDTs, respectively. Overall, consuming any fish species contaminated with DDTs would result in a lifetime cancer risk since it is greater than one in a million. Therefore, the current carcinogenic risk associated with DDTs should be a concern, predominantly in the case of the largest fish species, \u003cem\u003eC. gariepinus\u003c/em\u003e. To minimize exposure to contaminants in fish, it is advisable to consume smaller and younger fish, as they generally have lower concentrations of contaminants. These findings align with previous research conducted at Lake Ziway by Yohannes et al. (\u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e2014\u003c/span\u003e), as well as studies conducted in South Africa and China, which also indicated a cancer risk associated with DDTs in fish consumption (Pheiffer et al., \u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e2018\u003c/span\u003e; Yu et al., \u003cspan citationid=\"CR36\" class=\"CitationRef\"\u003e2014\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eHuman health risks are influenced by various sources of uncertainty, including factors such as fish preparation and cooking methods, nutrition adequacy, prior health conditions, and the development of pregnancy in women. These factors can impact the health risk condition differently. In susceptible subgroups, even low levels of contamination can exacerbate their situations, leading to health stress that healthy persons do not often experience. It is important to consider these factors as essentials which may change the potential risk levels associated with contaminants (USEPA, \u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e2000a\u003c/span\u003e).\u003c/p\u003e "},{"header":"Conclusion","content":"\u003cp\u003eLake Ziway exhibits relatively high levels of contamination from organochlorine pesticides (OCPs), organophosphorus pesticides (OPPs), and carbamates (CMs). Positive detections included Σ HCH, Σ DDTs, HCB, Σ heptachlor, chlorpyrifos, propoxur, and diazinon. However, aldrin, dieldrin, β-HCH, γ-HCH, endosulfan I, endosulfan sulfate, bendiocarb, profenofos, chlordane-trans, chlordane-cis, methoxychlor, and chlorpyrifos-methyl were below detection limits. DDTs were the most abundant contaminant, especially in the fatty African sharp-tooth catfish (C. \u003cem\u003egariepinus\u003c/em\u003e). The pattern of OCP contamination in the fish species was found to follow the order: DDT\u0026thinsp;\u0026gt;\u0026thinsp;HPTs\u0026thinsp;\u0026gt;\u0026thinsp;HCB\u0026thinsp;\u0026gt;\u0026thinsp;HCH. The study also revealed the bioaccumulation and biomagnification of DDTs, diazinon, heptachlor, and chlorpyrifos, all of which were significantly related to the size of the fish species. The health risk assessment indicated that consuming all four fish species could pose cancer risks due to DDTs, particularly the catfish due to its size. While non-carcinogenic health risks were not observed, the levels of DDTs and diazinon in all fish species exceeded the EU's recommended maximum residue limit (MRL), suggesting that these pollutants could accumulate in the human body and pose health concerns. It is recommended that food web studies be conducted to gain reliable information on pesticide biomagnification at different trophic levels. Besides, future research should explore viable treatment options for removing pesticides from the water resource.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003eAcknowledgment\u003c/p\u003e\n\u003cp\u003eThe authors have acknowledged the laboratory and research facility support of the Ethiopian Civil Service University, Ziway Fishery Laboratory, and the Ethiopian Food and Drug Authority (EFDA) laboratory.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCorresponding author\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eCorrespondence to Mekonnen Maschal Tarekegn\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eAuthors contribution\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eMekonnen Maschal Tarekegn initiated the research concept, framed the methodology, supervised the laboratory activities, data collection, and analysis, and finalized the report including the manuscript preparation. Dagnachew Lelisa Duga initiated the research proposal, collected samples, carried out lab activities, performed the data analysis, wrote the report, and prepared the manuscript. Yitayal Addis Alemayehu participated in the supervision of laboratory activities, data collection, analysis, and report writing including manuscript preparation. Mitiku Adisu Worku participated in the methodology development and supervised the data collection and analysis, participated in the report writing and manuscript preparation.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eData availability\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eData will be made available upon request.\u003c/p\u003e\n\u003cp\u003eDeclarations Ethics approval and consent to participate\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eNot applicable.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eConsent for publication \u0026nbsp;\u003c/p\u003e\n\u003cp\u003eNot applicable.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eCompeting interests\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThe authors declare no competing interests\u003c/p\u003e\n\u003cp\u003eFunding\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThere was no funding to carry out this study. \u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eAbera Lemma, Getahun, A., \u0026amp; Lemma, B. (2018). Changes in Fish Diversity and Fisheries in Ziway-Shala Basin: The Case of Lake Ziway, Ethiopia. \u003cem\u003eJournal of Fisheries \u0026amp; Livestock Production\u003c/em\u003e, \u003cem\u003e06\u003c/em\u003e(01), 1\u0026ndash;7. https://doi.org/10.4172/2332-2608.1000263\u003c/li\u003e\n\u003cli\u003eAdegun, A. O., Akinnifesi, T. A., Ololade, I. A., Busquets, R., Hooda, P. S., Cheung, P. C. W., Aseperi, A. K., \u0026amp; Barker, J. (2020). Quantification of neonicotinoid pesticides in six cultivable fish species from the river Owena in Nigeria and a template for food safety assessment. \u003cem\u003eWater (Switzerland)\u003c/em\u003e, \u003cem\u003e12\u003c/em\u003e(9). https://doi.org/10.3390/W12092422\u003c/li\u003e\n\u003cli\u003eAwulachew, S. B., Yilma, A. D., Loulseged, M., Loiskandl, W., Ayana, M., \u0026amp; Tena, A. (2007). Water Resources and Irrigation Development in Ethiopia. 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(2012). \u003cem\u003eCorrect Equations for Calculating the Maximum Allowable Fish Consumption Rate for Human Health Risk Assessment Considering the Noncarcinogenic Effects of Multiple Contaminants in Fish\u003c/em\u003e. \u003cem\u003e10481\u003c/em\u003e(1), 10481\u0026ndash;10482.\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"bioaccumulation, concentration, fish, health risks, pesticides","lastPublishedDoi":"10.21203/rs.3.rs-6016451/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6016451/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eLake Ziway, located in the Ethiopian Rift Valley, faces significant environmental pressure due to intensive agricultural and floriculture practices. Pesticides are heavily utilized to boost production. This study examined the concentrations, bioaccumulation, and health risks associated with 22 selected pesticides in four fish species: \u003cem\u003eOreochromis niloticus, Cyprinus carpio, Carassius carrasius\u003c/em\u003e, and \u003cem\u003eClarias gariepinus\u003c/em\u003e. A total of 48 fish, grouped by size into three sets for each species, were sourced from local fisheries and analyzed in duplicate. The dorsal muscle samples were extracted using a speed extractor, purified with florisil, and quantified using gas chromatography coupled with mass spectrometry (GC-MS/MS). Most compounds showed mean recoveries between 60% and 120%, except for dieldrin (51.33%) and bendiocarb (121.86%). Detection limits ranged from 0.01 to 2.6 \u0026micro;g kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e. Positive pesticide residues, including Σ HCH, Σ DDTs, HCB, Σ heptachlor, chlorpyrifos, propoxur, and diazinon, were detected at concentrations between 0.010 and 66.44 \u0026micro;g kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e. However, levels of β-HCH, γ-HCH, aldrin, dieldrin, endosulfan I, endosulfan sulfate, bendiocarb, profenofos, chlordane-trans, chlordane-cis, methoxychlor, and chlorpyrifos-methyl were below the detection limit. DDTs were the most prevalent contaminants, with concentrations ranging from 5.08 to 213.61 \u0026micro;g kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e, likely due to historical contamination from past practice. Prolonged consumption of pesticide-contaminated fish poses carcinogenic risks, highlighting the need for stringent enforcement of pesticide regulations.\u003c/p\u003e","manuscriptTitle":"Assessment of Pesticide Contamination Level of Fish and Human Health Risks in Lake Ziway, Ethiopia","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-03-19 08:23:12","doi":"10.21203/rs.3.rs-6016451/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"bcc5e7c0-6abd-4ce5-8904-fcf31015194f","owner":[],"postedDate":"March 19th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-04-29T03:46:37+00:00","versionOfRecord":[],"versionCreatedAt":"2025-03-19 08:23:12","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-6016451","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6016451","identity":"rs-6016451","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}