Geological and Climatic Influences on Natural Radioactivity in Drinking Water and Their Health Impacts: A Study of Dassie and Kombolcha Towns, Ethiopia

Geological and Climatic Influences on Natural Radioactivity in Drinking Water and Their Health Impacts: A Study of Dassie and Kombolcha Towns, 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 Article Geological and Climatic Influences on Natural Radioactivity in Drinking Water and Their Health Impacts: A Study of Dassie and Kombolcha Towns, Ethiopia Hailu Geremew, Yimam Mekonnen, Ashenafi Admasu This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7932825/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 17 Mar, 2026 Read the published version in Scientific Reports → Version 1 posted 15 You are reading this latest preprint version Abstract This study investigates geological and climatic influences on natural radioactivity levels in drinking water from Dassie and Kombolcha towns in Ethiopia’s northern plateau. The basaltic and sedimentary mudrock formations of the region contain elevated natural radionuclide levels, while climatic factors such as precipitation, soil moisture, and humidity enhance their mobility and transport into water sources. Kombolcha, located at a lower altitude, shows higher radionuclide concentrations due to runoff and downward transport along the Borkena River, intensified by rainfall. Uranium’s greater solubility compared to thorium results in higher activity levels across both towns, with consistently elevated uranium and thorium values in Kombolcha. Radiation dose assessments reveal significant health risks, particularly in spring and headwater sources, where uranium concentrations exceed safe limits. These findings highlight the combined role of geology and climate in shaping natural radioactivity patterns, with important implications for long-term health risks, monitoring, and mitigation strategies. Earth and environmental sciences/Climate sciences Earth and environmental sciences/Environmental sciences Earth and environmental sciences/Hydrology Earth and environmental sciences/Natural hazards Natural radioactivity Uranium and thorium concentrations Geological formations Climatic factors Geochemical influences Radiation dose assessment Figures Figure 1 Figure 2 1. Introduction Radionuclides are atoms with unstable nuclei that release radiation as they decay to form stable nuclei. They originate from both natural and artificial sources, but in drinking water systems their occurrence is primarily linked to natural geological and climatic factors. Uranium, thorium, and potassium-40, present in the Earth's crust, are released into water depending on the rock types and the surrounding environmental conditions. Geological formations, such as basaltic, sedimentary, igneous, and metamorphic rocks, are the primary sources of radionuclides, while climatic conditions like precipitation, humidity, and soil moisture regulate their mobility and transport. Together, these factors determine the levels of radionuclides in drinking water and ultimately shape potential health risks for human populations. Uranium is commonly found in geological formations like granitic and sedimentary rocks, which are rich in uranium-bearing minerals such as uraninite, pitchblende, and coffinite. Studies have shown that areas with high concentrations of these rocks tend to have elevated levels of uranium in the environment that leach to the groundwater. As a study conducted in Finland indicates groundwater in granitic bedrock areas had significantly higher uranium concentrations compared to other regions [ 1 , 2 ]. Thorium is primarily found in igneous and metamorphic rocks, particularly in thorium-rich minerals like monazite and thorite. As some investigations indicates, thorium levels in drinking water are generally lower than uranium due to its lower solubility in geochemical solutions, even in ground water. However, regions with thorium-rich geological formations, such as certain areas in India and western part of Africa, have been reported to have higher thorium concentrations in groundwater [ 2 – 4 ]. Potassium-40 is a naturally occurring isotope of potassium and is abundant in many types of rocks, especially in feldspar and mica minerals found in granitic and volcanic rocks. The distribution of potassium-40 in drinking water is influenced by the presence of these minerals in the geological formation. Even if potassium is necessary for human’s body development, studies in some countries like Japan have shown regions with volcanic rocks have higher concentrations of potassium-40 in groundwater [ 4 , 5 ]. These radionuclides can be dissolved in geochemical solutions and/or water from geological formations containing these elements. Drinking water contaminated with these radionuclides can pose significant health risks to humans. Uranium in drinking water is a significant concern due to its both chemical toxicity and radioactivity. Some of the symptoms of chronic ingestion of uranium are kidney damage as uranium tends to accumulate in the kidneys, and causing lung cancer as uranium decay progeny accumulated in the lung [ 6 , 7 ]. Furthermore, uranium's radiological hazard twigs from its decay products, which emit alpha particles. While alpha particles cannot penetrate the skin, they can cause significant damage if ingested, potentially leading to cancer and other health issues. Radon, a decay product of uranium, is a significant concern in drinking water. It can be released into the air during water use, contributing to indoor air pollution. Inhalation of radon and its progeny increases the risk of lung cancer [ 8 , 9 ]. Moreover, ingestion of radon-contaminated water can increase the risk of stomach cancer. Thorium, another naturally occurring radionuclide, can also be present in drinking water. Its health impacts are less well-studied compared to uranium, but it is known to increase the risk of liver diseases and lung cancer when inhaled or ingested in large amounts [ 10 ]. Potassium-40 ( 40 K) is a naturally occurring isotope of potassium. While potassium is an essential nutrient, its radioactive isotope can contribute to an individual's internal radiation dose. The health risks associated with 40 K are generally lower compared to uranium and thorium, due to its widespread distribution and essential biological role in human’s body [ 11 ]. The towns of Dassie and Kombolcha in Ethiopia are rapidly growing urban centers with diverse water sources, like river/running water, headwater (spring water) and underground water. The potential for radionuclide contamination of drinking water in these study areas is high as the regions are found in Ethiopian northern plateau. These study areas are found in the northern plateaus of Ethiopia’s covered by radionuclide hosting rocks like sediments, metamorphic and others. This necessitates thorough investigation to ensure the safety and health of the populations relying on these water sources [ 13 ]. The general objective of this study is to assess and analyze the levels of natural radioactivity influenced by geological and climatic conditions in drinking water and the corresponding radiological health risks in Kombolcha and Dassie towns, with a specific focus on uranium, thorium, and potassium concentrations using gamma ray spectrometry. 2. Materials and Methods This study integrates geological and climatic analyses with radiometric measurements to understand the influences on natural radioactivity in drinking water. Water samples were collected from Dassie and Kombolcha towns, representing different altitudes and geological settings. The methodology included gamma spectrometry for radionuclide activity measurement, geological characterization of the formations surrounding water sources, and incorporation of climatic parameters such as precipitation, humidity, and soil moisture. Climatic data for the study period (2020–2022) were obtained from NASA POWER datasets and used to interpret the seasonal mobility of radionuclides. This combined approach ensured that both geological and climatic influences were captured in the analysis of uranium, thorium, and potassium activity concentrations and their associated health impacts. 2.1. The Study Areas The samples of study were collected from Dassie and Kombolcha towns with an elevation ranging between 2470 and 2550 meters above sea level. The area is home to a population of over 2 Millions. 2.2. Principle of Gamma Spectrometry Sodium Iodide based gamma spectrometry is a technique used to measure and analyze the energy and intensity of gamma rays emitted by radionuclides found in drinking waters collected from the study areas. Sodium iodide (NaI) detectors are commonly used due to their high efficiency. For the purpose of this study, we used a moderate sized NaI(Tl), thallium activated detector of size 4.5x4.5 cm crystal. After photomultiplier tube, we used MASTRO-32 computer program to analyze gamma spectrum. 2.3. Equipment and Calibration The gamma spectrometry system comprises all the necessary equipment, where the shielding principle was done by using a compacted 10cm thickness of concreate. Calibration of the spectrometer is essential for accurate measurements and performed by using Cs-137 and Na-22 known standards of gamma-emitting radionuclides to establish the energy calibration and efficiency of the detector [ 12 ]. 3.4. Sample Collection and Preparation Water samples from Dassie and Kombolcha towns, which are above 25 km far away from each other, were collected using standardized procedures as recommended by several national and international guide lines to avoid contamination. Each sample will be filtered and stored in clean, airtight containers to achieve a secular equilibrium. The samples were then measured for more than 10-hours to ensure detectable levels of radionuclides spectra for analysis. 3.5. Measurement and Analysis The prepared samples will be placed in the NaI detector, and gamma spectra will be acquired over a specified period to ensure adequate counting statistics. The spectra will be analyzed to identify and quantify the radionuclides present using MASTRO-32 computer program. This involves comparing the measured spectra with known reference spectra of radionuclides like soil-6 and soil-375 [ 13 , 14 ]. The activity concentrations of the identified radionuclides were then calculated using the following formula: \(\:A=\frac{C}{E.t.V}\) …………………………………………………………………………………. 1 Where: - A is the activity concentration (Bq/L) , - C is the net count rate (counts per second) , - E is the detection efficiency , - t is the counting time (seconds) , - V is the volume of the sample (liters). 3.6. Quality Control and Assurance Quality control measures include the use of blank samples for the reduction of background radiation, duplicate samples that were collected from different site, and standard reference materials, soil-6 and soil-375 to ensure the accuracy and reliability of the results. Regular calibration of the gamma spectrometry system and validation of analytical procedures were considered for the quality assurance [ 15 ]. 3.7. Data Interpretation and Radiation Dose Calculation The obtained activity concentrations of radionuclides will be used to calculate the annual effective dose for individuals consuming the water [ 14 , 16 , 17 ]. This will be done using the dose conversion factors provided by the International Commission on Radiological Protection (ICRP) as follows: \(\:D=\sum\:_{i=1}^{n}Ci\left(D.C.{F}_{i}.I\right)\) …………………………………………………….……………2 where : - D is the annual effective dose (mSv/year) , -C i is the activity concentration of radionuclide i (Bq/L) , -DCF i is the dose conversion factor for radionuclide i (mSv/Bq) [ 18 ], -I is the annual intake of drinking water (L/year). 3. Results and Discussions 3.1. Results The gamma spectrometry analysis of drinking water samples from Dassie and Kombolcha towns revealed variations in natural radionuclide activity concentrations that closely align with both geological formations and climatic conditions. Water sources in basaltic and sedimentary mudrock formations showed elevated uranium and thorium concentrations, while seasonal precipitation and soil moisture were found to enhance the leaching and transport of these radionuclides. Kombolcha, located at a lower altitude, consistently exhibited higher radionuclide activity levels compared to Dassie, reflecting not only its geological context but also the influence of runoff and river transport driven by rainfall. Overall, uranium showed greater solubility and mobility compared to thorium, which explains its consistently higher activity levels across water sources. The results confirm that the combined effects of geology and climate are central to understanding radioactivity patterns in the study area. Natural Radionuclide Activity Concentration A gamma spectrometer was used to measure the activity values of natural radionuclides in drinking water samples collected from Dassie and Kombolcha towns. The water samples were classified into three categories: underground drinking water, head/spring water, and running/river water. Table 1 Activity concentration of natural radionuclides in underground drinking water and their relation to local geological formations and climatic influences. Selected Towns Site Station Sample Code Activity concentration (mBq/L) 232 Th 226 Ra 40 K Dessie Gerado S1 0.03 \(\:8\pm\:\) 0.005 \(\:1.870\pm\:\) 0.140 \(\:131\pm\:\) 3.100 S2 \(\:BDL\) \(\:BDL\) \(\:320\pm\:\) 5.200 S3 \(\:0.079\pm\:\) 0.002 \(\:1.520\pm\:\) 0.060 \(\:123\pm\:\) 2.230 Avg. 0.039 \(\:\pm\:\) 0.005 \(\:1.130\pm\:\) 0.152 \(\:191\pm\:6.451\) Tita S1 \(\:BDL\) \(\:1.190\pm\:\) 0.180 \(\:108\pm\:\) 2.410 S2 \(\:0.089\pm\:\) 0.008 \(\:BDL\) \(\:430\pm\:\) 7.430 S3 \(\:BDL\) \(\:0.930\pm\:\) 0.083 \(\:292\pm\:\) 4.310 Avg. 0.0300 \(\:\pm\:0.008\) \(\:0.706\pm\:0.198\) \(\:276\pm\:8.921\) Boru S1 \(\:0.080\pm\:\) 0.014 \(\:1.89\pm\:\) 0.210 \(\:260\pm\:\) 4.500 S2 \(\:0.051\pm\:\) 0.006 \(\:0.72\pm\:\) 0.030 \(\:560\pm\:\) 4.500 S3 \(\:0.034\pm\:\) 0.012 \(\:1.051\pm\:\) 0.110 \(\:389\pm\:\) 3.580 Avg. 0.055 \(\:\pm\:0.019\) \(\:1.230\pm\:0.239\) \(\:403\pm\:7.301\) Kombolcha Station1 S1 \(\:0.090\pm\:\:0.016\) \(\:1.145\pm\:\) 0.19 \(\:108\pm\:\) 2.410 S2 \(\:0.070\pm\:\) 0.009 \(\:1.432\pm\:\:0.020\) \(\:430\pm\:\) 7.430 S3 \(\:0.087\pm\:\) 0.015 \(\:0.960\pm\:\) 0.084 \(\:292\pm\:\) 4.310 Avg. 0.082 \(\:\pm\:0.016\) 1.179 \(\:\pm\:0.209\) 277 \(\:\pm\:8.921\) Station 2 S1 \(\:0.064\pm\:\) 0.011 \(\:1.692\pm\:\) 0.218 \(\:179\pm\:\) 2.528 S2 \(\:0.078\pm\:\) 0.012 \(\:0.522\pm\:\) 0.034 \(\:560\pm\:\) 4.500 S3 \(\:0.044\pm\:\) 0.010 \(\:1.121\pm\:\) 0.11 \(\:389\pm\:\) 3.580 Avg. 0.062 \(\:\pm\:0.019\) 1.112 \(\:\pm\:0.246\) 276 \(\:\pm\:6.281\) Reference Values [ 19 ] 0.05 0.5 * * 40 K, a radionuclide that occurs naturally in a fixed ratio to stable potassium, is not included. This is because potassium is an essential element for humans and its concentration in the body is controlled by metabolic processes. Table 1 summarizes the results of natural radioactivity concentrations in underground drinking water collected from the capital of the South Wollo Zone and the industrial town, Kombolcha. The measurements indicate that the thorium activity concentrations in samples collected from Dassie town, Gerado, and Tita are below the permissible values suggested by a joint report of the IAEA and WHO [ 21 ]. However, the Boru site shows a slightly higher value than the permissible limit for thorium. The uranium activity concentration in the same sampling area exceeds the recommended value from the report. Samples from Kombolcha town exceed the permissible values for both thorium and uranium activity concentrations. Potassium-40, as labeled and explained in Table 1 , has no permissible limit due to its importance for the human body. For head/spring water, samples were collected from three springs (Mume, Sireminch, and Minchitu) used for drinking and other purposes in Dassie town, and two springs (Station 1 and Station 2) in Kombolcha town. Three samples were prepared and analyzed for each head/spring water source as they were for underground water samples. Table 2 shows the experimental results of natural radioactivity concentrations in head/spring water. The experimental results indicate that the natural radionuclides have almost the same properties, with thorium activity concentrations being less than uranium activity concentrations in all samples from both study areas. However, the activity concentrations for head/spring water samples are higher than those for underground water for the three natural radionuclides. Table 2 Activity concentration of radionuclides in head (spring) water, highlighting geological sources and climate-driven mobilities. Selected Towns Site Station Sample Code Activity concentration (mBq/L) 232 Th 226 Ra 40 K Dessie Mume S1 \(\:0.075\pm\:\) 0.032 \(\:1.78\pm\:\) 0.44 \(\:333\pm\:\) 3.710 S2 \(\:BDL\) \(\:1.36\pm\:\) 0.12 \(\:620\pm\:\) 5.150 S3 \(\:0.140\pm\:\) 0.048 \(\:BDL\) \(\:280\pm\:\) 2.230 Avg. 0.071 \(\:\pm\:0.058\) \(\:1.050\pm\:0.456\) \(\:411\pm\:3.67\) 0 Sireminch S1 \(\:0.071\pm\:\) 0.005 \(\:2.120\pm\:\) 0.150 \(\:741\pm\:\) 6.310 S2 \(\:0.057\pm\:\) 0.011 \(\:0.780\pm\:\) 0.061 \(\:518\pm\:\) 4.860 S3 \(\:0.023\pm\:\) 0.009 \(\:BDL\) \(\:846\pm\:\) 7.560 Avg. 0.051 \(\:\pm\:0.015\) \(\:0.970\pm\:0.07\) 0 \(\:702\pm\:6.240\) Minchitu S1 \(\:0.061\pm\:\) 0.026 \(\:1.77\pm\:\) 0.20 \(\:BDL\) S2 \(\:BDL\) \(\:2.27\pm\:\) 0.52 \(\:290\pm\:\) 2.210 S3 \(\:BDL\) \(\:BDL\) \(\:473\pm\:\) 3.150 Avg. 0.0203 \(\:\pm\:0.026\) \(\:1.35\pm\:\) 0.557 \(\:188\pm\:1.790\) kombolcha Station 1 S1 \(\:0.021\pm\:\) 0.004 \(\:2.213\pm\:\) 0.156 \(\:646\pm\:\) 6.310 S2 \(\:0.087\pm\:\) 0.021 \(\:1.708\pm\:\) 0.081 \(\:432\pm\:\) 4.860 S3 \(\:0.043\pm\:\) 0.010 \(\:1.208\pm\:\) 0.062 \(\:567\pm\:\) 5.560 Avg. 0.050 \(\:\pm\:0.004\) 1.710 \(\:\pm\:0.156\) 548 \(\:\pm\:9.713\) Station 2 S1 \(\:0.021\pm\:\) 0.026 \(\:3.670\pm\:\) 0.820 \(\:363\pm\:\) 3.105 S2 0.063 \(\:\pm\:0.018\) \(\:2.476\pm\:\) 0.752 \(\:392\pm\:\) 3.210 S3 0.043 \(\:\pm\:0.008\) \(\:3.272\pm\:\) 0.642 \(\:543\pm\:\) 4.415 Avg. 0.042 \(\:\pm\:0.032\) 3.139 \(\:\pm\:1.284\) 433 \(\:\pm\:6.280\) Reference Values [ 19 ] 0.05 0.5 * The activity concentration of thorium in spring water from Dassie and Kombolcha towns is nearly equal to the recommended value of 0.05 mBq/L, as reported jointly by the FAO, WHO, and IAEA [ 21 ]. However, the uranium activity concentration in the same water samples exceeds the recommended value of 0.5 mBq/L. Additionally, Potassium-40 shows elevated activity concentrations in both towns. This radionuclide is categorized as a light nuclide, and most light nuclides are utilized in body development. Therefore, the radiation dose from Potassium-40 is not considered as significant as that from heavy nuclides [ 22 ]. It is important to note that the results vary across different locations due to the geological and geochemical characteristics of the headwaters. The measured activity concentrations of the three radionuclides are higher in the headwaters from Dassie compared to those from Kombolcha. This difference is attributed to the distinct geological and topographical features of the two towns, which affect the chemical properties of the radionuclides. Samples of running water were collected from two rivers in each town: the Borkena and Gerado rivers in Dassie, and the Borkena and Berberewonze rivers in Kombolcha. Notably, the Borkena River flows through both towns, while the Gerado River is confined to Dassie. Three representative samples were taken from each river, and the average value was used for subsequent analysis. Table 3 presents the experimental results of natural radioactivity concentration in the running water, measured in becquerels per liter (Bq/L). The mean activity concentrations in the river water samples exceeded those found in underground and headwater samples. It is important to note that the water was unfiltered during sampling; untreated river water samples were analyzed directly. Table 3 Activity concentration of radionuclides in running water, showing the combined effects of geological background and precipitation-driven runoff. Selected Towns Site Station Sample Code Activity concentration (Bq/L) 232 Th 226 Ra 40 K Dessie Borkena S1 \(\:0.054\pm\:\) 0.012 \(\:0.780\pm\:\) 0.030 \(\:1.610\pm\:\) 0.740 S2 \(\:0.180\pm\:\) 0.062 \(\:1.410\pm\:\) 0.150 \(\:2.250\pm\:\) 0.850 S3 \(\:BDL\) \(\:1.020\pm\:\) 0.120 \(\:0.890\pm\:\) 0.110 Avg. 0.078 \(\:\pm\:\) 0.063 \(\:1.070\pm\:\) 0.194 1.58 \(\:0\pm\:\) 0.560 Gerado S1 \(\:0.096\pm\:\) 0.031 \(\:1.32\pm\:\) 0.072 \(\:1.280\pm\:\) 0.420 S2 \(\:BDL\) \(\:0.55\pm\:\) 0.068 \(\:0.130\pm\:\) 0.020 S3 \(\:0.194\pm\:\) 0.065 \(\:0.18\pm\:\) 0.014 \(\:1.010\pm\:\) 0.190 Avg. 0.097 \(\:\pm\:\) 0.072 0.687 \(\:\pm\:\) 0.072 0.806 \(\:\pm\:0.210\) kombolcha Berberewonze S1 \(\:0.044\pm\:\) 0.022 \(\:0.780\pm\:\) 0.030 \(\:1.610\pm\:\) 0.740 S2 \(\:0.148\pm\:\) 0.082 \(\:1.410\pm\:\) 0.150 \(\:2.250\pm\:\) 0.850 S3 0.048 \(\:\pm\:\) 0.035 \(\:1.020\pm\:\) 0.120 \(\:0.890\pm\:\) 0.110 Avg. 0.08 \(\:\pm\:0.092\) 1.070 \(\:\pm\:\:0.120\) 1.583 \(\:\pm\:1.132\) Borkena S1 \(\:0.069\pm\:\) 0.013 \(\:1.307\pm\:\) 0.072 \(\:3.828\pm\:\) 0.812 S2 \(\:0.076\pm\:\) 0.014 \(\:1.505\pm\:\) 0.068 \(\:4.183\pm\:\) 0.902 S3 \(\:0.274\pm\:\) 0.085 \(\:2.128\pm\:\) 0.014 \(\:2.201\pm\:\) 0.329 Avg. 0.140 \(\:\pm\:0.087\) 1.647 \(\:\pm\:0.100\) 3.404 \(\:\pm\:1.257\) Reference Value If the river that crosses the two town (Borkena) considered, activity concentration at Kombolcha town is higher than at Dassie town. The flow of rainfall and other geochemical solutions are from Dassie to Kombolcha town. This is considered as a cause of variation of activity concentration at the two towns. The more soluble radionuclide (Uranium) has more concentration in the river water. The activity concentration of potassium does not show variation with thorium and uranium as in the samples of underground water and head water. This can be as a result of chemical properties of potassium hosting geological formations. Radiation Doses from Natural Radionuclides in Drinking Water Numerous studies have investigated the occurrence of natural radionuclides in drinking water from various sources, including groundwater, surface water, and bottled water. The concentrations of these radionuclides vary significantly depending on the geological characteristics of the region, water treatment processes, and other factors. Based on the investigated activity concentrations on natural radionuclides in underground water samples, the resulting radiation dose for the selected towns according to Eq. 2 are as in table below. Table 4 Average activity concentration and annual effective dose from radionuclides in underground drinking water, linked to geological formations and climate factors. Selected Towns Site Station Average Activity concentrations (mBq/L) Annual effective dose (mSv/year) , 232 Th 226 Ra 40 K Dessie Gerado 0.039 \(\:1.130\) \(\:191\) 1.10199 Tita 0.030 \(\:0.706\) \(\:276\) 1.39852 Boru 0.055 \(\:1.230\) \(\:403\) 2.08462 Kombolcha Station 1 0.082 1.179 277 1.50846 Station 2 0.062 1.112 276 1.48688 Reference Values 0.05 0.5 * 1 232 Th values are generally below the reference value of 0.05 mBq/L, except in Kombolcha (Site 1). 226 Ra values exceed the reference value of 0.5 mBq/L at all sites. 40 K does not have a reference value, but shows significant variability across sites. Annual Effective Dose; All sites exceed the reference annual effective dose of 1 mSv/year, with Boru (Dassie) showing the highest value of 2.08462 mSv/year. The activity concentrations of 226 Ra are consistently above the reference value, indicating a potential radiological concern. The annual effective doses at all sites are above the recommended reference value, suggesting a need for further investigation and potential mitigation measures to reduce exposure. The Table 5 provided the measured activity concentrations of radionuclides 232 Th, 226 Ra, and 40 K in Head (spring) drinking water from various sites in selected towns. It also shows the resulting annual effective dose in millisieverts per year (mSv/year) as well. Table 5 Average activity concentration and annual effective dose from head (spring) drinking water, demonstrating geological and climatic influences on dose variation. Selected Towns Site Station Average Activity concentrations (mBq/L) Annual effective dose (mSv/year) , 232 Th 226 Ra 40 K Dessie Mume 0.071 1.050 411 2.08673 Sireminch 0.051 0.970 702 3.38408 Minchity 0.020 1.350 188 1.13019 Kombolcha Station 1 0.050 1.710 548 2.83817 Station 2 0.042 3.139 433 2.60842 Reference Values 0.05 0.5 * 1 All measured values for 232 Th are either at or slightly above the reference value, with Minchity having the lowest and Mume having the highest concentration. 226 Ra, all measured values exceed the reference value significantly, particularly in Kombolcha Station 2. All sites have annual effective doses exceeding this reference value, indicating a higher potential radiation risk from drinking water in these locations. Sireminch in Dassie has the highest annual effective dose (3.38408 mSv/year), while Minchity in Dassie has the lowest among the measured sites but still above the reference value (1.13019 mSv/year). 3.2. Discussions The findings underscore that not only geology but also climatic factors such as precipitation, humidity, and soil moisture strongly influence radionuclide mobility. Seasonal rainfall enhances leaching and transport of uranium and thorium, especially along hydrological pathways like the Borkena River. Thus, both geological formations and climatic variations act together to shape the natural radioactivity levels in drinking water across Dassie and Kombolcha. Natural Radionuclide Activity Concentration As it is able to seen from Fig. 1 , the geological formation of the two towns is from Basaltic and Sedimentary mud rocks. The natural occurrences of uranium and thorium in such geological formations are 0.1-1ppm and 0.1-4ppm in Basaltic respectively, and 1-5ppm and 10-13ppm in Sedimentary Mud rocks respectively [ 20 ]. The chemical properties of these radionuclides in geochemical solution and water determines their concentrations in drinking water. Surface soil moisture, humidity and precipitation of an area enhance the concentrations by facilitating mobilities of radionuclides [ 21 , 22 ]. As humidity, soil moisture and precipitation data, Fig. 2 , of the three years (2020, 2021 and 2022) indicates, mobilities of soluble radionuclides permeable. There is no water shade that prevent the mobilities of these radionuclides. The solubility of uranium in geochemical solution and even in water is higher than thorium. As this study indicates, the activity concentration of uranium is higher than thorium. Among the two towns, the measured activity concentration at Kombolcha town is higher than Dassie town. As from the Fig. 2 , the topography of the two towns is, Dassie is highly elevated than Kombolcha town and all movements of solutions are from Dassie to Kombolcha town gradually following locally known river Borkena shown in Fig. 1 . (D). This transport the radionuclides from Dassie to Kombolcha and enhance the activity concentrations of natural radionuclides in water at Kombolcha town, especially for running/river water. The underground mobility characters of these radionuclides increase their activity concentrations at lower altitude, which is a gradual character of their geochemical mobilities. Relatively their activity measurements at Kombolcha town are higher than Dassie town for underground drinking water, head/spring water and running water. Surface mobilities by running water is the main factor for the activity enhancement at lower altitude, Kombolcha town. The two towns of this study are enclosed by Ethiopian northern plateau formed from igneous and sedimentary rocks. Such types of geological formations are rich in uranium, thorium and potassium contents [ 1 ]. The gradual mixing of these geological formations with water content of the study area increases the activity concentrations of radionuclides. So, as it is able to understand from references [ 1 ] geological formations and geochemical conditions contribute to the elevated values of activity concentrations in Dassie and Kombolcha towns. The weather conditions; surface soil moisture, relative humidity and precipitations facilitate the mobilities of natural radionuclides based on the topography of the study area [ 4 ]. This study found that the more soluble natural radionuclides deposited at lower altitude, more at Kombolcha town than Dassie town. The magnitudes of activity concentration of uranium radionuclide in water samples are higher than thorium due to its more solubility in chemical solutions and water. Radiation Doses from Natural Radionuclides Radiation doses from natural radionuclides in drinking water are an important public health concern because prolonged exposure to radiation, even at low levels, can pose health risks. Natural radionuclides, such as uranium, thorium, radon, and their decay products, are commonly found in varying concentrations in drinking water. The highest annual effective dose is observed in Sireminch (3.38408 mSv/year), followed by Mume (2.08673 mSv/year) in Dassie, and Site Station 1 (2.83817 mSv/year) in Kombolcha. Minchity in Dassie has the lowest annual effective dose (1.13019 mSv/year), followed by Site Station 2 in Kombolcha (2.60842 mSv/year). All sites have 226 Ra levels exceeding the reference value, indicating a potential radiological health risk due to its high radiotoxicity and ability to replace calcium in bones. Although 40 K is a naturally occurring isotope with relatively low radiotoxicity, its high activity concentrations could contribute significantly to the overall radiation dose. While most sites have 232 Th levels close to or slightly above the reference value, the potential health impact is relatively lower compared to 226 Ra. In general, certain sites, particularly Sireminch in Dassie and Station 1 in Kombolcha, exhibit higher annual effective doses, primarily due to elevated 226 Ra and 40 K concentrations. Continuous monitoring and potential mitigation measures are recommended to ensure the safety of the drinking water in these regions. 4. Conclusions This study demonstrates that natural radioactivity in drinking water is shaped by the interplay of geological formations and climatic conditions. The basaltic and sedimentary mudrocks of Dassie and Kombolcha are rich in uranium, thorium, and potassium, providing a geological source of radionuclides. Climatic factors particularly precipitation, humidity, and soil moisture enhance radionuclide mobility, facilitating their leaching and transport into underground, spring, and river water sources. The lower altitude of Kombolcha, combined with rainfall-driven runoff from Dassie via the Borkena River, explains its consistently higher radionuclide activity concentrations. Radiation dose assessments revealed that annual effective doses in several sites exceed recommended safety limits, largely due to elevated uranium and radium concentrations, posing potential long-term health risks. These findings highlight the need for continuous monitoring and the integration of geological and climatic considerations in water safety assessments, with mitigation strategies aimed at protecting public health in Ethiopia’s northern plateau. Declarations Acknowledgement The authors would like to thank Wollo University for supporting this work and all individuals who assisted during field sampling and data collection. Special appreciation is extended to those who provided access to climatic datasets and local geological information, which were essential in linking environmental factors to the observed radioactivity patterns. Funding: This work was supported by Wollo University office of research and community service. Conflict of interest: There are no personal relationships that could have appeared to influence the work reported in this paper. Ethics approval and consent to participate: Not applicable. Consent for publication: Not applicable. Data availability: The climate factor data are available in https://power.larc.nasa.gov/data-access-viewer/ Authors contribution The first author designed the study, carried out the sample collection, geological analysis, and manuscript preparation. The second and third authors contributed to data analysis, integration of climatic datasets, and editing the manuscript in accordance with journal guidelines. All authors reviewed, approved, and agreed to the final version of the manuscript, ensuring that both geological and climatic influences were properly framed in the study. References Asikainen, M. and H. Kahlos, Natural radioactivity of drinking water in Finland. Health Physics, 1980. 39 (1): p. 77-83. Syaeful, H., I. Sukadana, and A. Sumaryanto, Radiometric mapping for naturally occurring radioactive materials (NORM) assessment in Mamuju, West Sulawesi. Atom Indonesia, 2014. 40 (1): p. 33-39. Sahoo, S.K.A., H.; Tokonami, S., & Sorimachi, A. , Thoron ( 220 Rn) in environment and its related issues. Journal of Nuclear and Radiochemical Sciences, 2010. 11 (1): p. 1-9. IAEA, Guidelines for radioelement mapping using gamma ray spectrometry data , ed. I. 1011–4289. 2003, VIENNA: AEA-TECDOC-1363. Yonehara, H., Aoyama, T., & Radford, E. P. , Natural background radiation and radon exposure in Japan. Health Physics, 1996. 71 (2): p. 340-345. Kurttio, P., et al., Renal effects of uranium in drinking water. Environmental health perspectives, 2002. 110 (4): p. 337-342. Ademola, J.A. and O.R. Ojeniran, Radon-222 from different sources of water and the assessment of health hazard. J Water Health, 2017. 15 (1): p. 97-102. Darby, S., et al., Radon in homes and risk of lung cancer: collaborative analysis of individual data from 13 European case-control studies. Bmj, 2005. 330 (7485): p. 223. Appleton, J.D., Radon: sources, health risks, and hazard mapping. Ambio, 2007. 36 (1): p. 85-9. Rowland, R., A. Stehney, and H. Lucas, Dose-response relationships for radium-induced bone sarcomas. Health Physics, 1983. 44 : p. 15-31. Comar, C.L., Radioactive isotopes in human nutrition: Their use and their effects. Radiation Research, 1964. 22 (2): p. 265-280. Gilmore, G., Practical gamma-ray spectroscopy . 2008: John Wiley & Sons. Knoll, G.F., Radiation detection and measurement . 2010: John Wiley & Sons. IAEA, Determination and Interpretation of Characteristic Limits for Radioactivity Measurements , in Series No. 48 , I.A.Q.i.N. Applications, Editor. 2017, VIENNA. ISO/IEC, General requirements for the competence of testing and calibration laboratories . 2017. Ibikunle, S., O. Ajayi, and O. Dada, Activity Concentration Assessment of Natural Radionuclides in Borehole Water and it‟ s Radiological Impact from Akure, Nigeria. Int J Sci Res, 2013. 4 : p. 2875-9. Ibikunle, S., et al., Natural radioactivity measurement of water and sediment from the historic Ikogosi warm and cold spring, Nigeria. Nigeria Journal of Pure and Applied Physics, 2018. 8 (1): p. 20-26. Eckerman, K., et al., ICRP publication 119: compendium of dose coefficients based on ICRP publication 60. Annals of the ICRP, 2012. 41 : p. 1-130. Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture, I.A.E.A., World Health Organization, Criteria for Radionuclide Activity Concentrations for Food and Drinking Water , I.T. SERIES, Editor. 2016, IAEA: VIENNA. A.M. Tye, A.E.M., P.L. Smedley, Distribution of Natural Radioactivity in the Environment . Open Report OR/17/01, ed. S.C.P. Land. 2017, British Geological Survey. Arogunjo, A., et al., Uranium and thorium in soils, mineral sands, water and food samples in a tin mining area in Nigeria with elevated activity. Journal of environmental radioactivity, 2009. 100 (3): p. 232-240. Skeppström, K. and B. Olofsson, Uranium and radon in groundwater. European water, 2007. 17 (18): p. 51-62. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Published Journal Publication published 17 Mar, 2026 Read the published version in Scientific Reports → Version 1 posted Editorial decision: Revision requested 06 Jan, 2026 Reviews received at journal 05 Jan, 2026 Reviews received at journal 21 Dec, 2025 Reviews received at journal 17 Dec, 2025 Reviewers agreed at journal 16 Dec, 2025 Reviewers agreed at journal 15 Dec, 2025 Reviewers agreed at journal 13 Dec, 2025 Reviewers agreed at journal 08 Nov, 2025 Reviewers agreed at journal 07 Nov, 2025 Reviewers agreed at journal 05 Nov, 2025 Reviewers invited by journal 05 Nov, 2025 Editor invited by journal 31 Oct, 2025 Editor assigned by journal 29 Oct, 2025 Submission checks completed at journal 29 Oct, 2025 First submitted to journal 23 Oct, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. 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-7932825","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":542076411,"identity":"29516d39-3830-42de-8e76-fe375cffc858","order_by":0,"name":"Hailu Geremew","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA7UlEQVRIiWNgGAWjYBACCWYGBiCSkAGyGR8ACR4+YrXwANnMBiAtbAS1MIC1MIC0sIE4DAS1SLbzHmAuqLHgMTh//Frl1xw7GTYG5oePbuDRIs3Ml8A845gEj8GNnLLbstuSgQ5jMzbOwaNFjpnHgJmHDaSFJ+225DYgG+gdacJa/gG1nD+TViy5rZ6wFmmQFt42oJYD6ccYP247TFiLZDOPwWHePgkeyRs5zNKM247zsDET8IvE+TOGj3m+1cnxnT/+8OPPbdX2/OzNDx/j0wICByAUyFMgmpmAciTA/oDxB/GqR8EoGAWjYAQBAGlrOj/dvvj4AAAAAElFTkSuQmCC","orcid":"","institution":"Wollo University","correspondingAuthor":true,"prefix":"","firstName":"Hailu","middleName":"","lastName":"Geremew","suffix":""},{"id":542076412,"identity":"260193b8-2f61-4f5e-a704-1f5a541c8927","order_by":1,"name":"Yimam Mekonnen","email":"","orcid":"","institution":"Wollo University","correspondingAuthor":false,"prefix":"","firstName":"Yimam","middleName":"","lastName":"Mekonnen","suffix":""},{"id":542076413,"identity":"27837eb1-235d-42e6-9f07-35a4d1a37ab2","order_by":2,"name":"Ashenafi Admasu","email":"","orcid":"","institution":"Wollo University","correspondingAuthor":false,"prefix":"","firstName":"Ashenafi","middleName":"","lastName":"Admasu","suffix":""}],"badges":[],"createdAt":"2025-10-23 13:53:15","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-7932825/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-7932825/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1038/s41598-026-43834-9","type":"published","date":"2026-03-17T15:58:47+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":96248423,"identity":"9eea1fa7-b795-4cb6-a08d-7278f8014c27","added_by":"auto","created_at":"2025-11-19 07:28:27","extension":"docx","order_by":0,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":511652,"visible":true,"origin":"","legend":"","description":"","filename":"ArticleA1.docx","url":"https://assets-eu.researchsquare.com/files/rs-7932825/v1/ef748a2d27a90c1c70629a73.docx"},{"id":96086082,"identity":"c723eb60-4525-4316-ae97-6972fcb344dc","added_by":"auto","created_at":"2025-11-17 12:28:47","extension":"json","order_by":1,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":4954,"visible":true,"origin":"","legend":"","description":"","filename":"8494f8c6c71e432da182377530f9a947.json","url":"https://assets-eu.researchsquare.com/files/rs-7932825/v1/e41677dd5d74ff710a8881cb.json"},{"id":96247048,"identity":"d8d3286c-afc6-48d6-b93a-a8e580ed6092","added_by":"auto","created_at":"2025-11-19 07:27:05","extension":"xml","order_by":2,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":113099,"visible":true,"origin":"","legend":"","description":"","filename":"8494f8c6c71e432da182377530f9a9471enriched.xml","url":"https://assets-eu.researchsquare.com/files/rs-7932825/v1/78d5f451fa142f2135914c68.xml"},{"id":96246713,"identity":"f8eb7184-3dbe-4ce3-a499-d2865ed56e2b","added_by":"auto","created_at":"2025-11-19 07:26:35","extension":"eps","order_by":4,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":89008,"visible":true,"origin":"","legend":"","description":"","filename":"drawingimage2.eps","url":"https://assets-eu.researchsquare.com/files/rs-7932825/v1/7d8dcd427f1af16b5609dcaf.eps"},{"id":96247780,"identity":"12b1e7ef-09ea-479d-a874-84cb1cb7d0f3","added_by":"auto","created_at":"2025-11-19 07:27:43","extension":"eps","order_by":5,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":92381,"visible":true,"origin":"","legend":"","description":"","filename":"drawingimage3.eps","url":"https://assets-eu.researchsquare.com/files/rs-7932825/v1/8f9a04f600e6ae4a07f5a52d.eps"},{"id":96248008,"identity":"c42bfeb6-8984-47e3-bb65-3ea3f8d3c537","added_by":"auto","created_at":"2025-11-19 07:27:57","extension":"png","order_by":6,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":391676,"visible":true,"origin":"","legend":"","description":"","filename":"floatimage1.png","url":"https://assets-eu.researchsquare.com/files/rs-7932825/v1/fc20f7fdd12c62c4468cf0f9.png"},{"id":96086089,"identity":"974d1355-3f19-4ff1-a55d-816a127425d8","added_by":"auto","created_at":"2025-11-17 12:28:48","extension":"png","order_by":7,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":120411,"visible":true,"origin":"","legend":"","description":"","filename":"Onlinefloatimage1.png","url":"https://assets-eu.researchsquare.com/files/rs-7932825/v1/a30790d0fe982e9cfd75464c.png"},{"id":96086085,"identity":"d2de18bc-f4c9-4b77-874b-a2b3f0834196","added_by":"auto","created_at":"2025-11-17 12:28:48","extension":"xml","order_by":8,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":112491,"visible":true,"origin":"","legend":"","description":"","filename":"8494f8c6c71e432da182377530f9a9471structuring.xml","url":"https://assets-eu.researchsquare.com/files/rs-7932825/v1/48cdde35bfe96ac1c9b643fc.xml"},{"id":96086090,"identity":"4ccb2896-2b4a-4208-8326-923cf0e8afcc","added_by":"auto","created_at":"2025-11-17 12:28:48","extension":"html","order_by":9,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":131821,"visible":true,"origin":"","legend":"","description":"","filename":"earlyproof.html","url":"https://assets-eu.researchsquare.com/files/rs-7932825/v1/1c44e5fb1de8397c4dd27307.html"},{"id":96086080,"identity":"2fd61269-f064-4d2b-9591-b32477e4c725","added_by":"auto","created_at":"2025-11-17 12:28:47","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":544901,"visible":true,"origin":"","legend":"\u003cp\u003eGeographical location, geological formations, and climatic context (altitude, rainfall patterns) of Dassie and Kombolcha towns.\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-7932825/v1/c6cea99014883f992be1dde1.png"},{"id":96086081,"identity":"827f7b6e-8f2e-486e-bfa5-0a6c749c09b9","added_by":"auto","created_at":"2025-11-17 12:28:47","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":40404,"visible":true,"origin":"","legend":"\u003cp\u003eClimatic parameters (precipitation, humidity, and soil moisture) influencing the mobility of natural radionuclides in the study area (Source: NASA POWER dataset).\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-7932825/v1/9b9a1eceeaadf29a2bbce2b3.png"},{"id":105224084,"identity":"1b010deb-0e8c-4210-b14a-444490e36a3d","added_by":"auto","created_at":"2026-03-23 16:12:19","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1624556,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7932825/v1/146e7fb4-9964-4bba-9d8f-d05b1537ebc8.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Geological and Climatic Influences on Natural Radioactivity in Drinking Water and Their Health Impacts: A Study of Dassie and Kombolcha Towns, Ethiopia","fulltext":[{"header":"1. Introduction","content":"\u003cp\u003eRadionuclides are atoms with unstable nuclei that release radiation as they decay to form stable nuclei. They originate from both natural and artificial sources, but in drinking water systems their occurrence is primarily linked to natural geological and climatic factors. Uranium, thorium, and potassium-40, present in the Earth's crust, are released into water depending on the rock types and the surrounding environmental conditions. Geological formations, such as basaltic, sedimentary, igneous, and metamorphic rocks, are the primary sources of radionuclides, while climatic conditions like precipitation, humidity, and soil moisture regulate their mobility and transport. Together, these factors determine the levels of radionuclides in drinking water and ultimately shape potential health risks for human populations.\u003c/p\u003e\u003cp\u003eUranium is commonly found in geological formations like granitic and sedimentary rocks, which are rich in uranium-bearing minerals such as uraninite, pitchblende, and coffinite. Studies have shown that areas with high concentrations of these rocks tend to have elevated levels of uranium in the environment that leach to the groundwater. As a study conducted in Finland indicates groundwater in granitic bedrock areas had significantly higher uranium concentrations compared to other regions [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eThorium is primarily found in igneous and metamorphic rocks, particularly in thorium-rich minerals like monazite and thorite. As some investigations indicates, thorium levels in drinking water are generally lower than uranium due to its lower solubility in geochemical solutions, even in ground water. However, regions with thorium-rich geological formations, such as certain areas in India and western part of Africa, have been reported to have higher thorium concentrations in groundwater [\u003cspan additionalcitationids=\"CR3\" citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e].\u003c/p\u003e\u003cp\u003ePotassium-40 is a naturally occurring isotope of potassium and is abundant in many types of rocks, especially in feldspar and mica minerals found in granitic and volcanic rocks. The distribution of potassium-40 in drinking water is influenced by the presence of these minerals in the geological formation. Even if potassium is necessary for human\u0026rsquo;s body development, studies in some countries like Japan have shown regions with volcanic rocks have higher concentrations of potassium-40 in groundwater [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eThese radionuclides can be dissolved in geochemical solutions and/or water from geological formations containing these elements. Drinking water contaminated with these radionuclides can pose significant health risks to humans. Uranium in drinking water is a significant concern due to its both chemical toxicity and radioactivity. Some of the symptoms of chronic ingestion of uranium are kidney damage as uranium tends to accumulate in the kidneys, and causing lung cancer as uranium decay progeny accumulated in the lung [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. Furthermore, uranium's radiological hazard twigs from its decay products, which emit alpha particles. While alpha particles cannot penetrate the skin, they can cause significant damage if ingested, potentially leading to cancer and other health issues.\u003c/p\u003e\u003cp\u003eRadon, a decay product of uranium, is a significant concern in drinking water. It can be released into the air during water use, contributing to indoor air pollution. Inhalation of radon and its progeny increases the risk of lung cancer [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e, \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. Moreover, ingestion of radon-contaminated water can increase the risk of stomach cancer.\u003c/p\u003e\u003cp\u003eThorium, another naturally occurring radionuclide, can also be present in drinking water. Its health impacts are less well-studied compared to uranium, but it is known to increase the risk of liver diseases and lung cancer when inhaled or ingested in large amounts [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e].\u003c/p\u003e\u003cp\u003ePotassium-40 (\u003csup\u003e40\u003c/sup\u003eK) is a naturally occurring isotope of potassium. While potassium is an essential nutrient, its radioactive isotope can contribute to an individual's internal radiation dose. The health risks associated with \u003csup\u003e40\u003c/sup\u003eK are generally lower compared to uranium and thorium, due to its widespread distribution and essential biological role in human\u0026rsquo;s body [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eThe towns of Dassie and Kombolcha in Ethiopia are rapidly growing urban centers with diverse water sources, like river/running water, headwater (spring water) and underground water. The potential for radionuclide contamination of drinking water in these study areas is high as the regions are found in Ethiopian northern plateau. These study areas are found in the northern plateaus of Ethiopia\u0026rsquo;s covered by radionuclide hosting rocks like sediments, metamorphic and others. This necessitates thorough investigation to ensure the safety and health of the populations relying on these water sources [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. The general objective of this study is to assess and analyze the levels of natural radioactivity influenced by geological and climatic conditions in drinking water and the corresponding radiological health risks in Kombolcha and Dassie towns, with a specific focus on uranium, thorium, and potassium concentrations using gamma ray spectrometry.\u003c/p\u003e"},{"header":"2. Materials and Methods","content":"\u003cp\u003eThis study integrates geological and climatic analyses with radiometric measurements to understand the influences on natural radioactivity in drinking water. Water samples were collected from Dassie and Kombolcha towns, representing different altitudes and geological settings. The methodology included gamma spectrometry for radionuclide activity measurement, geological characterization of the formations surrounding water sources, and incorporation of climatic parameters such as precipitation, humidity, and soil moisture. Climatic data for the study period (2020\u0026ndash;2022) were obtained from NASA POWER datasets and used to interpret the seasonal mobility of radionuclides. This combined approach ensured that both geological and climatic influences were captured in the analysis of uranium, thorium, and potassium activity concentrations and their associated health impacts.\u003c/p\u003e\n\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e\n \u003ch2\u003e2.1. The Study Areas\u003c/h2\u003e\n \u003cdiv class=\"BlockQuote\"\u003e\n \u003cp\u003eThe samples of study were collected from Dassie and Kombolcha towns with an elevation ranging between 2470 and 2550 meters above sea level. The area is home to a population of over 2 Millions.\u003c/p\u003e\n \u003c/div\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec4\" class=\"Section2\"\u003e\n \u003ch2\u003e2.2. Principle of Gamma Spectrometry\u003c/h2\u003e\n \u003cp\u003eSodium Iodide based gamma spectrometry is a technique used to measure and analyze the energy and intensity of gamma rays emitted by radionuclides found in drinking waters collected from the study areas. Sodium iodide (NaI) detectors are commonly used due to their high efficiency. For the purpose of this study, we used a moderate sized NaI(Tl), thallium activated detector of size 4.5x4.5 cm crystal. After photomultiplier tube, we used MASTRO-32 computer program to analyze gamma spectrum.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec5\" class=\"Section2\"\u003e\n \u003ch2\u003e2.3. Equipment and Calibration\u003c/h2\u003e\n \u003cp\u003eThe gamma spectrometry system comprises all the necessary equipment, where the shielding principle was done by using a compacted 10cm thickness of concreate. Calibration of the spectrometer is essential for accurate measurements and performed by using Cs-137 and Na-22 known standards of gamma-emitting radionuclides to establish the energy calibration and efficiency of the detector [\u003cspan class=\"CitationRef\"\u003e12\u003c/span\u003e].\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec6\" class=\"Section2\"\u003e\n \u003ch2\u003e3.4. Sample Collection and Preparation\u003c/h2\u003e\n \u003cp\u003eWater samples from Dassie and Kombolcha towns, which are above 25 km far away from each other, were collected using standardized procedures as recommended by several national and international guide lines to avoid contamination. Each sample will be filtered and stored in clean, airtight containers to achieve a secular equilibrium. The samples were then measured for more than 10-hours to ensure detectable levels of radionuclides spectra for analysis.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec7\" class=\"Section2\"\u003e\n \u003ch2\u003e3.5. Measurement and Analysis\u003c/h2\u003e\n \u003cp\u003eThe prepared samples will be placed in the NaI detector, and gamma spectra will be acquired over a specified period to ensure adequate counting statistics. The spectra will be analyzed to identify and quantify the radionuclides present using MASTRO-32 computer program. This involves comparing the measured spectra with known reference spectra of radionuclides like soil-6 and soil-375 [\u003cspan class=\"CitationRef\"\u003e13\u003c/span\u003e, \u003cspan class=\"CitationRef\"\u003e14\u003c/span\u003e]. The activity concentrations of the identified radionuclides were then calculated using the following formula:\u003c/p\u003e\n \u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:A=\\frac{C}{E.t.V}\\)\u003c/span\u003e\u003c/span\u003e\u0026hellip;\u0026hellip;\u0026hellip;\u0026hellip;\u0026hellip;\u0026hellip;\u0026hellip;\u0026hellip;\u0026hellip;\u0026hellip;\u0026hellip;\u0026hellip;\u0026hellip;\u0026hellip;\u0026hellip;\u0026hellip;\u0026hellip;\u0026hellip;\u0026hellip;\u0026hellip;\u0026hellip;\u0026hellip;\u0026hellip;\u0026hellip;\u0026hellip;\u0026hellip;\u0026hellip;\u0026hellip;\u0026hellip;\u0026hellip;\u0026hellip;. 1\u003c/p\u003e\n \u003cp\u003eWhere:\u003c/p\u003e\n \u003cp\u003e\u003cem\u003e- A is the activity concentration (Bq/L)\u003c/em\u003e,\u003c/p\u003e\n \u003cp\u003e\u003cem\u003e- C is the net count rate (counts per second)\u003c/em\u003e,\u003c/p\u003e\n \u003cp\u003e\u003cem\u003e- E is the detection efficiency\u003c/em\u003e,\u003c/p\u003e\n \u003cp\u003e\u003cem\u003e- t is the counting time (seconds)\u003c/em\u003e,\u003c/p\u003e\n \u003cp\u003e\u003cem\u003e- V is the volume of the sample (liters).\u003c/em\u003e\u003c/p\u003e\u003cbr\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec8\" class=\"Section2\"\u003e\n \u003ch2\u003e3.6. Quality Control and Assurance\u003c/h2\u003e\n \u003cp\u003eQuality control measures include the use of blank samples for the reduction of background radiation, duplicate samples that were collected from different site, and standard reference materials, soil-6 and soil-375 to ensure the accuracy and reliability of the results. Regular calibration of the gamma spectrometry system and validation of analytical procedures were considered for the quality assurance [\u003cspan class=\"CitationRef\"\u003e15\u003c/span\u003e].\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec9\" class=\"Section2\"\u003e\n \u003ch2\u003e3.7. Data Interpretation and Radiation Dose Calculation\u003c/h2\u003e\n \u003cp\u003eThe obtained activity concentrations of radionuclides will be used to calculate the annual effective dose for individuals consuming the water [\u003cspan class=\"CitationRef\"\u003e14\u003c/span\u003e, \u003cspan class=\"CitationRef\"\u003e16\u003c/span\u003e, \u003cspan class=\"CitationRef\"\u003e17\u003c/span\u003e]. This will be done using the dose conversion factors provided by the International Commission on Radiological Protection (ICRP) as follows:\u003c/p\u003e\n \u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:D=\\sum\\:_{i=1}^{n}Ci\\left(D.C.{F}_{i}.I\\right)\\)\u003c/span\u003e\u003c/span\u003e\u0026hellip;\u0026hellip;\u0026hellip;\u0026hellip;\u0026hellip;\u0026hellip;\u0026hellip;\u0026hellip;\u0026hellip;\u0026hellip;\u0026hellip;\u0026hellip;\u0026hellip;\u0026hellip;\u0026hellip;\u0026hellip;\u0026hellip;\u0026hellip;\u0026hellip;\u0026hellip;.\u0026hellip;\u0026hellip;\u0026hellip;\u0026hellip;\u0026hellip;2\u003c/p\u003e\n \u003cp\u003e\u003cem\u003ewhere\u003c/em\u003e:\u003c/p\u003e\n \u003cp\u003e\u003cem\u003e- D is the annual effective dose (mSv/year)\u003c/em\u003e,\u003c/p\u003e\n \u003cp\u003e\u003cem\u003e-C\u003c/em\u003e\u003csub\u003e\u003cem\u003ei\u003c/em\u003e\u003c/sub\u003e \u003cem\u003eis the activity concentration of radionuclide i (Bq/L)\u003c/em\u003e,\u003c/p\u003e\n \u003cp\u003e\u003cem\u003e-DCF\u003c/em\u003e\u003csub\u003e\u003cem\u003ei\u003c/em\u003e\u003c/sub\u003e \u003cem\u003eis the dose conversion factor for radionuclide i (mSv/Bq)\u003c/em\u003e[\u003cspan class=\"CitationRef\"\u003e18\u003c/span\u003e],\u003c/p\u003e\n \u003cp\u003e\u003cem\u003e-I is the annual intake of drinking water (L/year).\u003c/em\u003e\u003c/p\u003e\n\u003c/div\u003e"},{"header":"3. Results and Discussions","content":"\u003cdiv id=\"Sec11\" class=\"Section2\"\u003e\u003ch2\u003e3.1. Results\u003c/h2\u003e\u003cp\u003eThe gamma spectrometry analysis of drinking water samples from Dassie and Kombolcha towns revealed variations in natural radionuclide activity concentrations that closely align with both geological formations and climatic conditions. Water sources in basaltic and sedimentary mudrock formations showed elevated uranium and thorium concentrations, while seasonal precipitation and soil moisture were found to enhance the leaching and transport of these radionuclides. Kombolcha, located at a lower altitude, consistently exhibited higher radionuclide activity levels compared to Dassie, reflecting not only its geological context but also the influence of runoff and river transport driven by rainfall. Overall, uranium showed greater solubility and mobility compared to thorium, which explains its consistently higher activity levels across water sources. The results confirm that the combined effects of geology and climate are central to understanding radioactivity patterns in the study area.\u003c/p\u003e\u003cp\u003e\u003cb\u003eNatural Radionuclide Activity Concentration\u003c/b\u003e\u003c/p\u003e\u003cp\u003eA gamma spectrometer was used to measure the activity values of natural radionuclides in drinking water samples collected from Dassie and Kombolcha towns. The water samples were classified into three categories: underground drinking water, head/spring water, and running/river water.\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\u003eActivity concentration of natural radionuclides in underground drinking water and their relation to local geological formations and climatic influences.\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\u003eSelected Towns\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003eSite Station\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003eSample Code\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colspan=\"3\" nameend=\"c6\" namest=\"c4\"\u003e\u003cp\u003e\u003csup\u003eActivity concentration (mBq/L)\u003c/sup\u003e\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003csup\u003e232\u003c/sup\u003eTh\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003csup\u003e226\u003c/sup\u003eRa\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003csup\u003e40\u003c/sup\u003eK\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"11\" rowspan=\"12\"\u003e\u003cp\u003eDessie\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\" morerows=\"3\" rowspan=\"4\"\u003e\u003cp\u003eGerado\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eS1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.03\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:8\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.005\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:1.870\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.140\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:131\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 3.100\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eS2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:BDL\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:BDL\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:320\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 5.200\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eS3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:0.079\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.002\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:1.520\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.060\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:123\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 2.230\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eAvg.\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.039\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.005\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:1.130\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e0.152\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:191\\pm\\:6.451\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\" morerows=\"3\" rowspan=\"4\"\u003e\u003cp\u003eTita\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eS1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:BDL\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:1.190\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.180\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:108\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 2.410\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eS2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:0.089\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.008\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:BDL\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:430\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 7.430\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eS3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:BDL\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:0.930\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.083\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:292\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 4.310\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eAvg.\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.0300\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\pm\\:0.008\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:0.706\\pm\\:0.198\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:276\\pm\\:8.921\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\" morerows=\"3\" rowspan=\"4\"\u003e\u003cp\u003eBoru\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eS1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:0.080\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.014\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:1.89\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.210\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:260\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 4.500\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eS2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:0.051\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.006\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:0.72\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.030\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:560\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 4.500\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eS3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:0.034\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.012\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:1.051\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.110\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:389\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 3.580\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eAvg.\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.055\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\pm\\:0.019\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:1.230\\pm\\:0.239\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:403\\pm\\:7.301\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"7\" rowspan=\"8\"\u003e\u003cp\u003eKombolcha\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\" morerows=\"3\" rowspan=\"4\"\u003e\u003cp\u003eStation1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eS1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:0.090\\pm\\:\\:0.016\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:1.145\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.19\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:108\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 2.410\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eS2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:0.070\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.009\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:1.432\\pm\\:\\:0.020\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:430\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 7.430\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eS3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:0.087\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.015\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:0.960\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.084\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:292\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 4.310\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eAvg.\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.082\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\pm\\:0.016\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e1.179\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\pm\\:0.209\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e277\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\pm\\:8.921\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\" morerows=\"3\" rowspan=\"4\"\u003e\u003cp\u003eStation 2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eS1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:0.064\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.011\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:1.692\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.218\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:179\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 2.528\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eS2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:0.078\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.012\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:0.522\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.034\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:560\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 4.500\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eS3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:0.044\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.010\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:1.121\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.11\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:389\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 3.580\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eAvg.\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.062\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\pm\\:0.019\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e1.112\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\pm\\:0.246\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e276\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\pm\\:6.281\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"3\" nameend=\"c3\" namest=\"c1\"\u003e\u003cp\u003eReference Values [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.05\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\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\u003e\u003cb\u003e*\u003c/b\u003e \u003csup\u003e40\u003c/sup\u003eK, a radionuclide that occurs naturally in a fixed ratio to stable potassium, is not included. This is because potassium is an essential element for humans and its concentration in the body is controlled by metabolic processes.\u003c/p\u003e\u003cp\u003eTable\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e summarizes the results of natural radioactivity concentrations in underground drinking water collected from the capital of the South Wollo Zone and the industrial town, Kombolcha. The measurements indicate that the thorium activity concentrations in samples collected from Dassie town, Gerado, and Tita are below the permissible values suggested by a joint report of the IAEA and WHO [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e]. However, the Boru site shows a slightly higher value than the permissible limit for thorium. The uranium activity concentration in the same sampling area exceeds the recommended value from the report. Samples from Kombolcha town exceed the permissible values for both thorium and uranium activity concentrations. Potassium-40, as labeled and explained in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e, has no permissible limit due to its importance for the human body.\u003c/p\u003e\u003cp\u003eFor head/spring water, samples were collected from three springs (Mume, Sireminch, and Minchitu) used for drinking and other purposes in Dassie town, and two springs (Station 1 and Station 2) in Kombolcha town. Three samples were prepared and analyzed for each head/spring water source as they were for underground water samples. Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e shows the experimental results of natural radioactivity concentrations in head/spring water. The experimental results indicate that the natural radionuclides have almost the same properties, with thorium activity concentrations being less than uranium activity concentrations in all samples from both study areas. However, the activity concentrations for head/spring water samples are higher than those for underground water for the three natural radionuclides.\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\u003eActivity concentration of radionuclides in head (spring) water, highlighting geological sources and climate-driven mobilities.\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\u003eSelected Towns\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003eSite Station\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003eSample Code\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colspan=\"3\" nameend=\"c6\" namest=\"c4\"\u003e\u003cp\u003e\u003csup\u003eActivity concentration (mBq/L)\u003c/sup\u003e\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003csup\u003e232\u003c/sup\u003eTh\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003csup\u003e226\u003c/sup\u003eRa\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003csup\u003e40\u003c/sup\u003eK\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"11\" rowspan=\"12\"\u003e\u003cp\u003eDessie\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\" morerows=\"3\" rowspan=\"4\"\u003e\u003cp\u003eMume\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eS1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:0.075\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.032\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:1.78\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.44\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:333\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 3.710\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eS2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:BDL\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:1.36\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.12\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:620\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 5.150\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eS3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:0.140\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.048\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:BDL\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:280\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 2.230\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eAvg.\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.071\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\pm\\:0.058\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:1.050\\pm\\:0.456\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:411\\pm\\:3.67\\)\u003c/span\u003e\u003c/span\u003e0\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\" morerows=\"3\" rowspan=\"4\"\u003e\u003cp\u003eSireminch\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eS1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:0.071\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.005\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:2.120\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.150\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:741\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 6.310\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eS2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:0.057\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.011\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:0.780\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.061\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:518\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 4.860\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eS3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:0.023\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.009\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:BDL\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:846\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 7.560\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eAvg.\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.051\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\pm\\:0.015\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:0.970\\pm\\:0.07\\)\u003c/span\u003e\u003c/span\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:702\\pm\\:6.240\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\" morerows=\"3\" rowspan=\"4\"\u003e\u003cp\u003eMinchitu\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eS1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:0.061\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.026\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:1.77\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.20\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:BDL\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eS2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:BDL\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:2.27\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.52\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:290\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 2.210\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eS3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:BDL\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:BDL\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:473\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 3.150\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eAvg.\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.0203\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\pm\\:0.026\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:1.35\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e0.557\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:188\\pm\\:1.790\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"7\" rowspan=\"8\"\u003e\u003cp\u003ekombolcha\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\" morerows=\"3\" rowspan=\"4\"\u003e\u003cp\u003eStation 1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eS1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:0.021\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.004\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:2.213\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.156\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:646\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 6.310\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eS2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:0.087\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.021\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:1.708\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.081\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:432\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 4.860\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eS3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:0.043\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.010\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:1.208\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.062\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:567\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 5.560\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eAvg.\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.050\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\pm\\:0.004\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e1.710\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\pm\\:0.156\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e548 \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\pm\\:9.713\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\" morerows=\"3\" rowspan=\"4\"\u003e\u003cp\u003eStation 2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eS1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:0.021\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.026\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:3.670\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.820\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:363\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 3.105\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eS2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.063\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\pm\\:0.018\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:2.476\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.752\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:392\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 3.210\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eS3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.043\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\pm\\:0.008\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:3.272\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.642\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:543\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 4.415\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eAvg.\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.042 \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\pm\\:0.032\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e3.139 \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\pm\\:1.284\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e433 \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\pm\\:6.280\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"3\" nameend=\"c3\" namest=\"c1\"\u003e\u003cp\u003eReference Values [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cb\u003e0.05\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cb\u003e0.5\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cb\u003e*\u003c/b\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\u003eThe activity concentration of thorium in spring water from Dassie and Kombolcha towns is nearly equal to the recommended value of 0.05 mBq/L, as reported jointly by the FAO, WHO, and IAEA [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e]. However, the uranium activity concentration in the same water samples exceeds the recommended value of 0.5 mBq/L. Additionally, Potassium-40 shows elevated activity concentrations in both towns. This radionuclide is categorized as a light nuclide, and most light nuclides are utilized in body development. Therefore, the radiation dose from Potassium-40 is not considered as significant as that from heavy nuclides [\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e]. It is important to note that the results vary across different locations due to the geological and geochemical characteristics of the headwaters. The measured activity concentrations of the three radionuclides are higher in the headwaters from Dassie compared to those from Kombolcha. This difference is attributed to the distinct geological and topographical features of the two towns, which affect the chemical properties of the radionuclides.\u003c/p\u003e\u003cp\u003eSamples of running water were collected from two rivers in each town: the Borkena and Gerado rivers in Dassie, and the Borkena and Berberewonze rivers in Kombolcha. Notably, the Borkena River flows through both towns, while the Gerado River is confined to Dassie. Three representative samples were taken from each river, and the average value was used for subsequent analysis. Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e presents the experimental results of natural radioactivity concentration in the running water, measured in becquerels per liter (Bq/L). The mean activity concentrations in the river water samples exceeded those found in underground and headwater samples. It is important to note that the water was unfiltered during sampling; untreated river water samples were analyzed directly.\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\u003eActivity concentration of radionuclides in running water, showing the combined effects of geological background and precipitation-driven runoff.\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\u003eSelected Towns\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003eSite Station\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003eSample Code\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colspan=\"3\" nameend=\"c6\" namest=\"c4\"\u003e\u003cp\u003e\u003csup\u003eActivity concentration (Bq/L)\u003c/sup\u003e\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003csup\u003e232\u003c/sup\u003eTh\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003csup\u003e226\u003c/sup\u003eRa\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003csup\u003e40\u003c/sup\u003eK\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"7\" rowspan=\"8\"\u003e\u003cp\u003eDessie\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\" morerows=\"3\" rowspan=\"4\"\u003e\u003cp\u003eBorkena\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eS1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:0.054\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.012\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:0.780\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.030\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:1.610\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.740\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eS2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:0.180\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.062\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:1.410\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.150\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:2.250\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.850\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eS3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:BDL\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:1.020\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.120\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:0.890\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.110\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eAvg.\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.078\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e0.063\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:1.070\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e0.194\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e1.58\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:0\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e0.560\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\" morerows=\"3\" rowspan=\"4\"\u003e\u003cp\u003eGerado\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eS1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:0.096\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.031\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:1.32\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.072\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:1.280\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.420\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eS2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:BDL\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:0.55\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.068\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:0.130\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.020\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eS3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:0.194\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.065\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:0.18\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.014\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:1.010\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.190\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eAvg.\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.097\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e0.072\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.687\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e0.072\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.806\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\pm\\:0.210\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"7\" rowspan=\"8\"\u003e\u003cp\u003ekombolcha\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\" morerows=\"3\" rowspan=\"4\"\u003e\u003cp\u003eBerberewonze\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eS1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:0.044\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.022\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:0.780\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.030\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:1.610\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.740\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eS2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:0.148\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.082\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:1.410\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.150\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:2.250\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.850\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eS3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.048\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e0.035\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:1.020\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.120\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:0.890\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.110\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eAvg.\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.08 \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\pm\\:0.092\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e1.070 \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\pm\\:\\:0.120\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e1.583 \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\pm\\:1.132\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\" morerows=\"3\" rowspan=\"4\"\u003e\u003cp\u003eBorkena\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eS1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:0.069\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.013\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:1.307\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.072\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:3.828\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.812\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eS2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:0.076\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.014\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:1.505\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.068\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:4.183\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.902\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eS3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:0.274\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.085\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:2.128\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.014\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:2.201\\pm\\:\\)\u003c/span\u003e\u003c/span\u003e 0.329\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eAvg.\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.140 \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\pm\\:0.087\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e1.647 \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\pm\\:0.100\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e3.404 \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\pm\\:1.257\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"3\" nameend=\"c3\" namest=\"c1\"\u003e\u003cp\u003eReference Value\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003eIf the river that crosses the two town (Borkena) considered, activity concentration at Kombolcha town is higher than at Dassie town. The flow of rainfall and other geochemical solutions are from Dassie to Kombolcha town. This is considered as a cause of variation of activity concentration at the two towns. The more soluble radionuclide (Uranium) has more concentration in the river water. The activity concentration of potassium does not show variation with thorium and uranium as in the samples of underground water and head water. This can be as a result of chemical properties of potassium hosting geological formations.\u003c/p\u003e\u003cp\u003e\u003cb\u003eRadiation Doses from Natural Radionuclides in Drinking Water\u003c/b\u003e\u003c/p\u003e\u003cp\u003eNumerous studies have investigated the occurrence of natural radionuclides in drinking water from various sources, including groundwater, surface water, and bottled water. The concentrations of these radionuclides vary significantly depending on the geological characteristics of the region, water treatment processes, and other factors. Based on the investigated activity concentrations on natural radionuclides in underground water samples, the resulting radiation dose for the selected towns according to Eq.\u0026nbsp;2 are as in table below.\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\u003eAverage activity concentration and annual effective dose from radionuclides in underground drinking water, linked to geological formations and climate factors.\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\u003eSelected Towns\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003eSite Station\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colspan=\"3\" nameend=\"c5\" namest=\"c3\"\u003e\u003cp\u003e\u003csup\u003eAverage Activity concentrations (mBq/L)\u003c/sup\u003e\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e\u003cem\u003eAnnual effective dose (mSv/year)\u003c/em\u003e,\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003csup\u003e232\u003c/sup\u003eTh\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003csup\u003e226\u003c/sup\u003eRa\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003csup\u003e40\u003c/sup\u003eK\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003eDessie\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eGerado\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.039\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:1.130\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:191\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e1.10199\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eTita\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.030\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:0.706\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:276\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e1.39852\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eBoru\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.055\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:1.230\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:403\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e2.08462\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003eKombolcha\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eStation 1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.082\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1.179\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e277\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e1.50846\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eStation 2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.062\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1.112\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e276\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e1.48688\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e\u003cp\u003e\u003cb\u003eReference Values\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.05\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e*\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e1\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\u003e\u003csup\u003e232\u003c/sup\u003eTh values are generally below the reference value of 0.05 mBq/L, except in Kombolcha (Site 1). \u003csup\u003e226\u003c/sup\u003eRa values exceed the reference value of 0.5 mBq/L at all sites. \u003csup\u003e40\u003c/sup\u003eK does not have a reference value, but shows significant variability across sites. Annual Effective Dose; All sites exceed the reference annual effective dose of 1 mSv/year, with Boru (Dassie) showing the highest value of 2.08462 mSv/year. The activity concentrations of \u003csup\u003e226\u003c/sup\u003eRa are consistently above the reference value, indicating a potential radiological concern. The annual effective doses at all sites are above the recommended reference value, suggesting a need for further investigation and potential mitigation measures to reduce exposure.\u003c/p\u003e\u003cp\u003eThe Table \u003cspan refid=\"Tab5\" class=\"InternalRef\"\u003e5\u003c/span\u003e provided the measured activity concentrations of radionuclides \u003csup\u003e232\u003c/sup\u003eTh, \u003csup\u003e226\u003c/sup\u003eRa, and \u003csup\u003e40\u003c/sup\u003eK in Head (spring) drinking water from various sites in selected towns. It also shows the resulting annual effective dose in millisieverts per year (mSv/year) as well.\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\u003eAverage activity concentration and annual effective dose from head (spring) drinking water, demonstrating geological and climatic influences on dose variation.\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\" colspan=\"2\" morerows=\"1\" nameend=\"c2\" namest=\"c1\" rowspan=\"2\"\u003e\u003cp\u003eSelected Towns\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003eSite Station\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colspan=\"3\" nameend=\"c6\" namest=\"c4\"\u003e\u003cp\u003e\u003csup\u003eAverage Activity concentrations (mBq/L)\u003c/sup\u003e\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c7\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e\u003cem\u003eAnnual effective dose (mSv/year)\u003c/em\u003e,\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003csup\u003e232\u003c/sup\u003eTh\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003csup\u003e226\u003c/sup\u003eRa\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003csup\u003e40\u003c/sup\u003eK\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003eDessie\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e\u003cp\u003eMume\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.071\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e1.050\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e411\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e2.08673\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e\u003cp\u003eSireminch\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.051\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.970\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e702\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e3.38408\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e\u003cp\u003eMinchity\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.020\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e1.350\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e188\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e1.13019\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003eKombolcha\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e\u003cp\u003eStation 1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.050\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e1.710\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e548\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e2.83817\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e\u003cp\u003eStation 2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.042\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e3.139\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e433\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e2.60842\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"3\" nameend=\"c3\" namest=\"c1\"\u003e\u003cp\u003e\u003cb\u003eReference Values\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cb\u003e0.05\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cb\u003e0.5\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cb\u003e*\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e\u003cb\u003e1\u003c/b\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 measured values for \u003csup\u003e232\u003c/sup\u003eTh are either at or slightly above the reference value, with Minchity having the lowest and Mume having the highest concentration. \u003csup\u003e226\u003c/sup\u003eRa, all measured values exceed the reference value significantly, particularly in Kombolcha Station 2. All sites have annual effective doses exceeding this reference value, indicating a higher potential radiation risk from drinking water in these locations. Sireminch in Dassie has the highest annual effective dose (3.38408 mSv/year), while Minchity in Dassie has the lowest among the measured sites but still above the reference value (1.13019 mSv/year).\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec12\" class=\"Section2\"\u003e\u003ch2\u003e3.2. Discussions\u003c/h2\u003e\u003cp\u003eThe findings underscore that not only geology but also climatic factors such as precipitation, humidity, and soil moisture strongly influence radionuclide mobility. Seasonal rainfall enhances leaching and transport of uranium and thorium, especially along hydrological pathways like the Borkena River. Thus, both geological formations and climatic variations act together to shape the natural radioactivity levels in drinking water across Dassie and Kombolcha.\u003c/p\u003e\u003cp\u003e\u003cb\u003eNatural Radionuclide Activity Concentration\u003c/b\u003e\u003c/p\u003e\u003cp\u003eAs it is able to seen from Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e, the geological formation of the two towns is from Basaltic and Sedimentary mud rocks. The natural occurrences of uranium and thorium in such geological formations are 0.1-1ppm and 0.1-4ppm in Basaltic respectively, and 1-5ppm and 10-13ppm in Sedimentary Mud rocks respectively [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e]. The chemical properties of these radionuclides in geochemical solution and water determines their concentrations in drinking water. Surface soil moisture, humidity and precipitation of an area enhance the concentrations by facilitating mobilities of radionuclides [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e, \u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e]. As humidity, soil moisture and precipitation data, Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e, of the three years (2020, 2021 and 2022) indicates, mobilities of soluble radionuclides permeable.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003eThere is no water shade that prevent the mobilities of these radionuclides. The solubility of uranium in geochemical solution and even in water is higher than thorium. As this study indicates, the activity concentration of uranium is higher than thorium. Among the two towns, the measured activity concentration at Kombolcha town is higher than Dassie town. As from the Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e, the topography of the two towns is, Dassie is highly elevated than Kombolcha town and all movements of solutions are from Dassie to Kombolcha town gradually following locally known river Borkena shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e. (D). This transport the radionuclides from Dassie to Kombolcha and enhance the activity concentrations of natural radionuclides in water at Kombolcha town, especially for running/river water.\u003c/p\u003e\u003cp\u003eThe underground mobility characters of these radionuclides increase their activity concentrations at lower altitude, which is a gradual character of their geochemical mobilities. Relatively their activity measurements at Kombolcha town are higher than Dassie town for underground drinking water, head/spring water and running water. Surface mobilities by running water is the main factor for the activity enhancement at lower altitude, Kombolcha town. The two towns of this study are enclosed by Ethiopian northern plateau formed from igneous and sedimentary rocks. Such types of geological formations are rich in uranium, thorium and potassium contents [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. The gradual mixing of these geological formations with water content of the study area increases the activity concentrations of radionuclides. So, as it is able to understand from references [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e] geological formations and geochemical conditions contribute to the elevated values of activity concentrations in Dassie and Kombolcha towns. The weather conditions; surface soil moisture, relative humidity and precipitations facilitate the mobilities of natural radionuclides based on the topography of the study area [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. This study found that the more soluble natural radionuclides deposited at lower altitude, more at Kombolcha town than Dassie town. The magnitudes of activity concentration of uranium radionuclide in water samples are higher than thorium due to its more solubility in chemical solutions and water.\u003c/p\u003e\u003cp\u003e\u003cb\u003eRadiation Doses from Natural Radionuclides\u003c/b\u003e\u003c/p\u003e\u003cp\u003eRadiation doses from natural radionuclides in drinking water are an important public health concern because prolonged exposure to radiation, even at low levels, can pose health risks. Natural radionuclides, such as uranium, thorium, radon, and their decay products, are commonly found in varying concentrations in drinking water.\u003c/p\u003e\u003cp\u003eThe highest annual effective dose is observed in Sireminch (3.38408 mSv/year), followed by Mume (2.08673 mSv/year) in Dassie, and Site Station 1 (2.83817 mSv/year) in Kombolcha. Minchity in Dassie has the lowest annual effective dose (1.13019 mSv/year), followed by Site Station 2 in Kombolcha (2.60842 mSv/year). All sites have \u003csup\u003e226\u003c/sup\u003eRa levels exceeding the reference value, indicating a potential radiological health risk due to its high radiotoxicity and ability to replace calcium in bones. Although \u003csup\u003e40\u003c/sup\u003eK is a naturally occurring isotope with relatively low radiotoxicity, its high activity concentrations could contribute significantly to the overall radiation dose. While most sites have \u003csup\u003e232\u003c/sup\u003eTh levels close to or slightly above the reference value, the potential health impact is relatively lower compared to \u003csup\u003e226\u003c/sup\u003eRa. In general, certain sites, particularly Sireminch in Dassie and Station 1 in Kombolcha, exhibit higher annual effective doses, primarily due to elevated \u003csup\u003e226\u003c/sup\u003eRa and \u003csup\u003e40\u003c/sup\u003eK concentrations. Continuous monitoring and potential mitigation measures are recommended to ensure the safety of the drinking water in these regions.\u003c/p\u003e\u003c/div\u003e"},{"header":"4. Conclusions","content":"\u003cp\u003eThis study demonstrates that natural radioactivity in drinking water is shaped by the interplay of geological formations and climatic conditions. The basaltic and sedimentary mudrocks of Dassie and Kombolcha are rich in uranium, thorium, and potassium, providing a geological source of radionuclides. Climatic factors particularly precipitation, humidity, and soil moisture enhance radionuclide mobility, facilitating their leaching and transport into underground, spring, and river water sources. The lower altitude of Kombolcha, combined with rainfall-driven runoff from Dassie via the Borkena River, explains its consistently higher radionuclide activity concentrations. Radiation dose assessments revealed that annual effective doses in several sites exceed recommended safety limits, largely due to elevated uranium and radium concentrations, posing potential long-term health risks. These findings highlight the need for continuous monitoring and the integration of geological and climatic considerations in water safety assessments, with mitigation strategies aimed at protecting public health in Ethiopia\u0026rsquo;s northern plateau.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eAcknowledgement\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors would like to thank Wollo University for supporting this work and all individuals who assisted during field sampling and data collection. Special appreciation is extended to those who provided access to climatic datasets and local geological information, which were essential in linking environmental factors to the observed radioactivity patterns.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding:\u003c/strong\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis work was supported by Wollo University office of research and community service.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConflict of interest:\u003c/strong\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThere are no personal relationships that could have appeared to influence the work reported in this paper.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate: \u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication:\u0026nbsp;\u003c/strong\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData availability:\u003c/strong\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe climate factor data are available in https://power.larc.nasa.gov/data-access-viewer/\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors contribution\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe first author designed the study, carried out the sample collection, geological analysis, and manuscript preparation. The second and third authors contributed to data analysis, integration of climatic datasets, and editing the manuscript in accordance with journal guidelines. All authors reviewed, approved, and agreed to the final version of the manuscript, ensuring that both geological and climatic influences were properly framed in the study.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eAsikainen, M. and H. Kahlos, \u003cem\u003eNatural radioactivity of drinking water in Finland.\u003c/em\u003e Health Physics, 1980. \u003cstrong\u003e39\u003c/strong\u003e(1): p. 77-83.\u003c/li\u003e\n\u003cli\u003eSyaeful, H., I. Sukadana, and A. Sumaryanto, \u003cem\u003eRadiometric mapping for naturally occurring radioactive materials (NORM) assessment in Mamuju, West Sulawesi.\u003c/em\u003e Atom Indonesia, 2014. \u003cstrong\u003e40\u003c/strong\u003e(1): p. 33-39.\u003c/li\u003e\n\u003cli\u003eSahoo, S.K.A., H.; Tokonami, S., \u0026amp; Sorimachi, A. , \u003cem\u003eThoron (\u003csup\u003e220\u003c/sup\u003eRn) in environment and its related issues.\u003c/em\u003e Journal of Nuclear and Radiochemical Sciences, 2010. \u003cstrong\u003e11\u003c/strong\u003e(1): p. 1-9.\u003c/li\u003e\n\u003cli\u003eIAEA, \u003cem\u003eGuidelines for radioelement mapping using gamma ray spectrometry data\u003c/em\u003e, ed. I. 1011\u0026ndash;4289. 2003, VIENNA: AEA-TECDOC-1363.\u003c/li\u003e\n\u003cli\u003eYonehara, H., Aoyama, T., \u0026amp; Radford, E. P. , \u003cem\u003eNatural background radiation and radon exposure in Japan.\u003c/em\u003e Health Physics, 1996. \u003cstrong\u003e71\u003c/strong\u003e(2): p. 340-345.\u003c/li\u003e\n\u003cli\u003eKurttio, P., et al., \u003cem\u003eRenal effects of uranium in drinking water.\u003c/em\u003e Environmental health perspectives, 2002. \u003cstrong\u003e110\u003c/strong\u003e(4): p. 337-342.\u003c/li\u003e\n\u003cli\u003eAdemola, J.A. and O.R. Ojeniran, \u003cem\u003eRadon-222 from different sources of water and the assessment of health hazard.\u003c/em\u003e J Water Health, 2017. \u003cstrong\u003e15\u003c/strong\u003e(1): p. 97-102.\u003c/li\u003e\n\u003cli\u003eDarby, S., et al., \u003cem\u003eRadon in homes and risk of lung cancer: collaborative analysis of individual data from 13 European case-control studies.\u003c/em\u003e Bmj, 2005. \u003cstrong\u003e330\u003c/strong\u003e(7485): p. 223.\u003c/li\u003e\n\u003cli\u003eAppleton, J.D., \u003cem\u003eRadon: sources, health risks, and hazard mapping.\u003c/em\u003e Ambio, 2007. \u003cstrong\u003e36\u003c/strong\u003e(1): p. 85-9.\u003c/li\u003e\n\u003cli\u003eRowland, R., A. Stehney, and H. Lucas, \u003cem\u003eDose-response relationships for radium-induced bone sarcomas.\u003c/em\u003e Health Physics, 1983. \u003cstrong\u003e44\u003c/strong\u003e: p. 15-31.\u003c/li\u003e\n\u003cli\u003eComar, C.L., \u003cem\u003eRadioactive isotopes in human nutrition: Their use and their effects.\u003c/em\u003e Radiation Research, 1964. \u003cstrong\u003e22\u003c/strong\u003e(2): p. 265-280.\u003c/li\u003e\n\u003cli\u003eGilmore, G., \u003cem\u003ePractical gamma-ray spectroscopy\u003c/em\u003e. 2008: John Wiley \u0026amp; Sons.\u003c/li\u003e\n\u003cli\u003eKnoll, G.F., \u003cem\u003eRadiation detection and measurement\u003c/em\u003e. 2010: John Wiley \u0026amp; Sons.\u003c/li\u003e\n\u003cli\u003eIAEA, \u003cem\u003eDetermination and Interpretation of Characteristic Limits for Radioactivity Measurements\u003c/em\u003e, in\u003cem\u003e Series No. 48\u003c/em\u003e, I.A.Q.i.N. Applications, Editor. 2017, VIENNA.\u003c/li\u003e\n\u003cli\u003eISO/IEC, \u003cem\u003eGeneral requirements for the competence of testing and calibration laboratories\u003c/em\u003e. 2017.\u003c/li\u003e\n\u003cli\u003eIbikunle, S., O. Ajayi, and O. Dada, \u003cem\u003eActivity Concentration Assessment of Natural Radionuclides in Borehole Water and it‟ s Radiological Impact from Akure, Nigeria.\u003c/em\u003e Int J Sci Res, 2013. \u003cstrong\u003e4\u003c/strong\u003e: p. 2875-9.\u003c/li\u003e\n\u003cli\u003eIbikunle, S., et al., \u003cem\u003eNatural radioactivity measurement of water and sediment from the historic Ikogosi warm and cold spring, Nigeria.\u003c/em\u003e Nigeria Journal of Pure and Applied Physics, 2018. \u003cstrong\u003e8\u003c/strong\u003e(1): p. 20-26.\u003c/li\u003e\n\u003cli\u003eEckerman, K., et al., \u003cem\u003eICRP publication 119: compendium of dose coefficients based on ICRP publication 60.\u003c/em\u003e Annals of the ICRP, 2012. \u003cstrong\u003e41\u003c/strong\u003e: p. 1-130.\u003c/li\u003e\n\u003cli\u003eJoint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture, I.A.E.A., World Health Organization, \u003cem\u003eCriteria for Radionuclide Activity Concentrations for Food and Drinking Water\u003c/em\u003e, I.T. SERIES, Editor. 2016, IAEA: VIENNA.\u003c/li\u003e\n\u003cli\u003eA.M. Tye, A.E.M., P.L. Smedley, \u003cem\u003eDistribution of Natural Radioactivity in the Environment\u003c/em\u003e. Open Report OR/17/01, ed. S.C.P. Land. 2017, British Geological Survey.\u003c/li\u003e\n\u003cli\u003eArogunjo, A., et al., \u003cem\u003eUranium and thorium in soils, mineral sands, water and food samples in a tin mining area in Nigeria with elevated activity.\u003c/em\u003e Journal of environmental radioactivity, 2009. \u003cstrong\u003e100\u003c/strong\u003e(3): p. 232-240.\u003c/li\u003e\n\u003cli\u003eSkeppstr\u0026ouml;m, K. and B. Olofsson, \u003cem\u003eUranium and radon in groundwater.\u003c/em\u003e European water, 2007. \u003cstrong\u003e17\u003c/strong\u003e(18): p. 51-62.\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"scientific-reports","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"scirep","sideBox":"Learn more about [Scientific Reports](http://www.nature.com/srep/)","snPcode":"","submissionUrl":"","title":"Scientific Reports","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Scientific Reports","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Natural radioactivity, Uranium and thorium concentrations, Geological formations, Climatic factors, Geochemical influences, Radiation dose assessment","lastPublishedDoi":"10.21203/rs.3.rs-7932825/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7932825/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eThis study investigates geological and climatic influences on natural radioactivity levels in drinking water from Dassie and Kombolcha towns in Ethiopia\u0026rsquo;s northern plateau. The basaltic and sedimentary mudrock formations of the region contain elevated natural radionuclide levels, while climatic factors such as precipitation, soil moisture, and humidity enhance their mobility and transport into water sources. Kombolcha, located at a lower altitude, shows higher radionuclide concentrations due to runoff and downward transport along the Borkena River, intensified by rainfall. Uranium\u0026rsquo;s greater solubility compared to thorium results in higher activity levels across both towns, with consistently elevated uranium and thorium values in Kombolcha. Radiation dose assessments reveal significant health risks, particularly in spring and headwater sources, where uranium concentrations exceed safe limits. These findings highlight the combined role of geology and climate in shaping natural radioactivity patterns, with important implications for long-term health risks, monitoring, and mitigation strategies.\u003c/p\u003e","manuscriptTitle":"Geological and Climatic Influences on Natural Radioactivity in Drinking Water and Their Health Impacts: A Study of Dassie and Kombolcha Towns, Ethiopia","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-11-17 12:28:43","doi":"10.21203/rs.3.rs-7932825/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2026-01-06T06:16:41+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-01-05T09:20:07+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-12-21T06:02:07+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-12-17T06:01:50+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"171951607799494559155175598664831480471","date":"2025-12-16T05:32:39+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"157777155643501248741556591604598988773","date":"2025-12-15T06:05:25+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"255498889730469828907676809650608824715","date":"2025-12-13T22:15:41+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"38720171451694102440576797382557944870","date":"2025-11-09T02:08:44+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"152896476488791284673795950681446032843","date":"2025-11-07T15:49:10+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"155601996660769239981952176244978336936","date":"2025-11-05T18:15:08+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-11-05T15:43:37+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2025-10-31T12:29:28+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-10-29T04:10:22+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-10-29T04:09:52+00:00","index":"","fulltext":""},{"type":"submitted","content":"Scientific Reports","date":"2025-10-23T13:39:47+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"scientific-reports","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"scirep","sideBox":"Learn more about [Scientific Reports](http://www.nature.com/srep/)","snPcode":"","submissionUrl":"","title":"Scientific Reports","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Scientific Reports","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"7ad94ab6-0a7d-4415-b8c2-adbb324726e2","owner":[],"postedDate":"November 17th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[{"id":57669526,"name":"Earth and environmental sciences/Climate sciences"},{"id":57669527,"name":"Earth and environmental sciences/Environmental sciences"},{"id":57669528,"name":"Earth and environmental sciences/Hydrology"},{"id":57669529,"name":"Earth and environmental sciences/Natural hazards"}],"tags":[],"updatedAt":"2026-03-23T16:08:38+00:00","versionOfRecord":{"articleIdentity":"rs-7932825","link":"https://doi.org/10.1038/s41598-026-43834-9","journal":{"identity":"scientific-reports","isVorOnly":false,"title":"Scientific Reports"},"publishedOn":"2026-03-17 15:58:47","publishedOnDateReadable":"March 17th, 2026"},"versionCreatedAt":"2025-11-17 12:28:43","video":"","vorDoi":"10.1038/s41598-026-43834-9","vorDoiUrl":"https://doi.org/10.1038/s41598-026-43834-9","workflowStages":[]},"version":"v1","identity":"rs-7932825","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7932825","identity":"rs-7932825","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}