Multi-Elemental Analysis of Lead, Antimony, and Tin in Household Paints and Raw Materials in Southwestern Nigeria

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However, the potential for concurrent exposure to other toxic elements in paints, such as antimony and tin, remains largely uninvestigated, representing a significant knowledge gap in risk assessment. We conducted a cross-sectional market survey in Southwestern Nigeria, analyzing 10 commercially available paint products and 10 raw materials using Energy Dispersive X-ray Fluorescence (XRF) spectroscopy. The results were benchmarked against international regulatory standards (90 ppm for lead). The findings were contextualized with data on child exposure behaviors from a related survey to assess potential health risks. Our analysis revealed a widespread non-compliance with safety standards. A staggering 90% of paint samples exceeded the 90 ppm lead limit, with a mean concentration of 1,086 ppm. Alarmingly, we identified widespread and extreme contamination with other toxic elements: antimony (mean: 31,379 ppm) and tin (mean: 35,896 ppm) were present in all samples. Arsenic was detected in 31% of samples, with one sample containing 4,355 ppm. Source analysis identified pigments (Yellow/Red Oxide) and additives (Calgon, PVA) as primary contamination sources. The Nigerian population, particularly children, is exposed to a dangerous combination of toxic elements from paints. This study moves beyond the well-documented lead problem to highlight a broader, under-recognized threat from antimony and tin. There is recommendation for robust enforcement of existing lead paint laws and the immediate expansion of regulatory frameworks to include other toxic metals. Public health interventions must focus on supply chain regulation, consumer awareness, and the promotion of safer alternatives to mitigate this preventable health risk. Lead Poisoning Child Health Environmental Exposure Household Products Public Health Policy Heavy Metals Nigeria Antimony Figures Figure 1 Figure 2 Figure 3 1. INTRODUCTION The global burden of disease attributable to toxic metal exposure is a major public health concern, with children being disproportionately affected [ 1 , 2 ]. Lead exposure, in particular, has been described as a "silent pandemic," causing an estimated 900,000 premature deaths annually and long-term neurodevelopmental damage in children who survive [ 3 , 4 ]. Despite its well-documented toxicity, lead remains a persistent hazard, especially in low- and middle-income countries (LMICs) where regulatory frameworks are often weak or poorly enforced [ 5 ]. A primary source of lead exposure in these settings is lead-based paint [ 6 , 7 ]. As paint deteriorates over time, it chips and chalks, contaminating household dust and soil. Children, through their natural hand-to-mouth behavior, are at the highest risk of ingesting this contaminated dust, leading to elevated blood lead levels (BLLs) associated with irreversible cognitive deficits, reduced educational attainment, and increased behavioral problems [ 4 , 8 ]. While the lead paint crisis in Nigeria has been previously noted [ 9 , 10 ], the public health narrative has remained narrowly focused on this single element. This singular focus risks overlooking a potentially more significant threat: the "cocktail effect" of simultaneous exposure to multiple toxic elements [ 11 ]. Elements like antimony (Sb), a possible human carcinogen linked to respiratory and cardiovascular issues [ 12 ], and tin (Sn), whose organic compounds are potent endocrine disruptors [ 13 ], are commonly used in paint formulations as flame retardants, biocides, and opacifiers. Their health impacts, particularly in combination with lead, are not well characterized but represent a critical gap in environmental health risk assessment. This study aims to bridge this gap by providing a public health-oriented assessment of toxic metal exposure from paints in Southwestern Nigeria. We employ X-ray Fluorescence (XRF) spectroscopy not as the study's centerpiece, but as a tool to generate evidence for public health action. Our objectives are: To quantify the concentrations of lead and other toxic metals (Sb, Sn, As, Cd) in commercially available paints. To assess the level of compliance with international safety standards and identify sources of contamination in the supply chain. To provide evidence-based recommendations for policy reform, regulatory enforcement, and targeted public health interventions. 2. MATERIALS AND METHODS 2.1. Study Design and Sample Collection A cross-sectional market survey was conducted to obtain a representative sample of paints available to consumers in Southwestern Nigeria. We purposively collected 10 ready-to-use paint products from major retail markets in Lagos, Oyo, and Osun states. To trace the source of contamination, we also collected 10 raw materials used in local paint production from three major suppliers in Ibadan, Lagos, and Osun states, selected based on their prominence in the local paint manufacturing supply chain. This two-tiered approach allows for targeted public health interventions at both the manufacturing and retail levels. The brands, types, locations, and colors of the paint samples are detailed in Table 1 . Table 1 Description of Paint Samples Analyzed by XRF S/N Brand Name Type of Paint Location Color 1 Apa coat Oil Paint Lagos White 2 Fine Coat Aluminum Paint Lagos White 3 Galaxy Plastic Paint Osun Orange 4 Perfect Oil Paint Osun Caramel 5 Princess Enamel Paint Oyo Black 6 Radius Enamel Paint Osun Blue 7 Rainlux Oil Paint Oyo White 8 Realux Enamel Paint Lagos Brown 9 Sedem Synthetic Rubber Lagos White 10 Vila paint Synthetic Rubber Oyo White 2.2. Elemental Analysis and Health Risk Benchmarking Elemental analysis was performed using a calibrated Energy Dispersive X-ray Fluorescence (XRF) spectrometer. We focused our quantitative reporting on elements of public health concern: Lead (Pb), Antimony (Sb), Tin (Sn), Arsenic (As), and Cadmium (Cd). The health risk was benchmarked by comparing lead concentrations directly against the stringent U.S. Consumer Product Safety Commission (CPSC) standard of 90 ppm [ 14 ], a widely accepted public health benchmark. The limits of detection (LOD) and quantification (LOQ) for the analyzed elements were as follows: Pb (LOD: 5 ppm, LOQ: 15 ppm), Sb (LOD: 10 ppm, LOQ: 30 ppm), Sn (LOD: 8 ppm, LOQ: 25 ppm), As (LOD: 3 ppm, LOQ: 10 ppm), Cd (LOD: 2 ppm, LOQ: 6 ppm). 2.3. Sample Preparation Samples were prepared according to their physical state to ensure homogeneity and optimal analysis, minimizing matrix effects [ 16 ]. Powdered Samples (calcium carbonate, titanium oxide, red oxide): These were homogenized using an agate mortar and pestle and then sieved through a 75 µm mesh to ensure uniform particle size. Approximately 5 grams of the homogenized powder were pressed into a 32-mm diameter pellet using a hydraulic press at a pressure of 10 tons for 2 minutes. Liquid Samples (liquid paints, formalin, ammonium hydroxide): Approximately 2 mL of the well-shaken sample was pipetted into a specialized liquid sample holder. The holder was sealed with a 6 µm thick Mylar film to prevent leakage and evaporation while allowing low-energy X-ray transmission. Solid/Gel Samples (resins, calgon): These were carefully cut or scooped to create a flat, uniform surface that completely covered the sample cup opening, ensuring infinite thickness for the X-ray beam. 2.4. XRF Instrumentation and Analytical Procedure Elemental analysis was performed at the National Agency for Science and Engineering Infrastructure (NASENI), Akure, Nigeria, using an Energy Dispersive X-ray Fluorescence (EDXRF) spectrometer (Model EDX3600B, Skyray Instrument). The instrument is equipped with a high-performance Rhodium (Rh) target X-ray tube and a high-resolution Silicon Drift Detector (SDD) with a resolution of < 140 eV at Mn Kα. The instrument can detect elements from Sodium (Na) to Uranium (U). 2.4.1. Instrument Calibration and Quality Assurance The spectrometer was calibrated using a suite of certified reference materials (CRMs) traceable to the National Institute of Standards and Technology (NIST). For quantitative analysis of lead, a specific calibration curve was established. Standards were prepared in-house by adding varying volumes (2, 4, 6, 8 mL) of a 1000 mg/L lead standard solution (AccuStandard) to 8g of high-purity, lead-free chalk powder. The mixtures were thoroughly homogenized, dried, and pressed into pellets, creating calibration points at approximately 250, 500, 750, and 1000 ppm. The linearity of the calibration curve was excellent (R² = 0.999). A typical calibration curve is shown in Fig. 1 . Quality control measures included: Analysis of a blank sample (chalk pellet) to check for contamination. Periodic analysis of a CRM to verify analytical accuracy. The recovery for lead was between 92–105%. Each sample was analyzed in triplicate, and the mean concentration was reported. The standard deviation (SD) reported in the tables represents the variation across different paint samples. 2.4.2. Analysis Conditions The analysis was conducted under an air atmosphere at room temperature (25 ± 2°C). The operating conditions were optimized for the detection of mid-Z and high-Z elements (Pb, Sb, Sn). The parameters were as follows: Voltage: 40 keV, Current: 350 µA, Medium filter, Live Time: 300 seconds, Atmosphere: Air The spectrum for each sample was acquired and processed using the instrument's dedicated software (EDXRF 3600B Software). The software automatically identified elements based on their characteristic X-ray peaks (Kα and Lα lines) and quantified their concentrations using the fundamental parameters method. 2.5. Data Analysis The acquired quantitative data were exported to Microsoft Excel 365 and SPSS Statistics (Version 28) for statistical analysis. Descriptive statistics (mean, median, standard deviation, minimum, and maximum) were calculated for the concentrations of all detected elements. The results for toxic metals were compared against established regulatory limits, primarily the U.S. CPSC standard of 90 ppm for lead in paint. 3. RESULTS 3.1. Multi-Elemental Composition Panorama The EDXRF analysis detected a total of 27 elements across the twenty samples. Elements consistently below the detection limit in all samples (Na, Mg, etc.) have been omitted from the main tables for clarity. The full detailed tables are available in the Supplementary Material. The elemental assessment revealed significant diversity in composition, reflecting the varied formulations of different paint types and raw materials. Titanium (Ti) was found at the highest concentration, reaching 598,464 ppm in a titanium oxide raw material sample, consistent with its use as a primary white pigment. Other major elements included Calcium (Ca) from extenders like calcium carbonate (max: 248,135 ppm), and Iron (Fe) from pigments like red and yellow oxide (max: 540,466 ppm). A typical XRF spectrum from a paint sample (Sedem Paint) is shown in Fig. 2 , illustrating the multiple elemental peaks detected. 3.2. Concentrations of Key Toxic Metals in Paints The concentrations of the five toxic metals of primary public health concern in the twenty paint samples are detailed in Table 2 and visualized in Fig. 3 . Table 2 Summary of Toxic Metal Concentrations in Paint Samples Metal Minimum Maximum Mean ± SD Median % Samples > 90 ppm (Pb) Pb 81 4,637 1,086 ± 1,566 189 90% As 0 4,355 604 ± 1,302 0 – Cd 0 2 0.4 ± 0.7 0 – Sb 23,134 38,434 31,379 ± 4,674 33,911 – Sn 28,610 43,812 35,896 ± 4,485 36,797 – Note: SD represents variation across different paint samples. Lead (Pb) : All paint samples contained detectable lead. The concentration ranged from 81 ppm to 4,637 ppm, with a mean concentration of 1,086 ppm and a median of 189 ppm. A staggering 90% of the paint samples exceeded the 90 ppm regulatory limit. The highest concentrations were found in synthetic rubber and enamel paints. Arsenic (As) : Arsenic was detected in 8 samples (31%). Concentrations ranged from below the detection limit to 4,355 ppm (Vila paint). The mean concentration across all samples was 604 ppm. Cadmium (Cd) : Cadmium was detected in only 4 samples at very low levels, ranging from 0 to 2 ppm. The mean concentration was 0.4 ppm. Antimony (Sb) : Antimony was detected in all paint samples at exceptionally high concentrations, ranging from 23,134 ppm to 38,434 ppm, with a mean of 31,379 ppm and little variation (SD = 4,674 ppm), suggesting its consistent use as an additive. Tin (Sn) : Tin was also detected in all paint samples at high concentrations, ranging from 28,610 ppm to 43,812 ppm, with a mean of 35,896 ppm. 3.3. Source Apportionment: Toxic Metals in Input Raw Materials The analysis of raw materials (Table 2 ) provided insights into potential sources of contamination. Lead (Pb) : The highest lead concentrations among raw materials were found in color pigments: Yellow Oxide (178 ppm) and Red Oxide (174 ppm). This indicates that these colorants are a primary source of lead contamination in the final paint products. Antimony (Sb) and Tin (Sn) : Raw materials like Calgon (Sb: 36,676 ppm; Sn: 39,335 ppm) and Polyvinyl Acetate (PVA) (Sb: 36,255 ppm; Sn: 41,608 ppm) showed extremely high levels. This suggests that these materials, likely used as dispersants or binders, are major contributors of Sb and Sn in the locally produced paints. Titanium Oxide , a common white pigment, contained 83 ppm of lead, demonstrating that even base materials can be contaminated. 4. DISCUSSION This study provides a multi-elemental assessment of metals in household paints in Southwestern Nigeria. By employing this approach, we have confirmed widespread non-compliance with lead standards and identified elevatead concentrations of antimony and tin. 4.1. Widespread Lead Contamination: A Persistent Crisis The findings of this study unequivocally confirm a widespread non-compliance with safety standards and ongoing lead paint crisis in Nigeria. The mean lead concentration of 1,086 ppm is more than twelve times the 90 ppm US CPSC limit [ 14 ] and significantly higher than the 600 ppm total lead limit stipulated in the Nigerian Industrial Standard (NIS 269:2017) [ 16 ]. This level of non-compliance (90% of samples) is consistent with recent studies from other LMICs. For instance, a 2023 analysis of paints from Uganda found a mean lead concentration of 4,900 ppm, with 67% of samples exceeding 90 ppm [ 17 ]. Similarly, a 2021 study in Kenya reported that 74% of paints violated the 90 ppm standard, with some samples containing over 15,000 ppm lead [ 18 ]. Our results, showing a mean of 1,086 ppm, fit within this troubling global pattern of regulatory failure in LMICs, underscoring that lead-based paints remain the norm rather than the exception in many markets. The high lead levels in raw pigments confirm that the contamination originates early in the supply chain, necessitating interventions at the point of import and local production. 4.2. High Levels Concentrations of Antimony and Tin A key finding of this study is the high concentrations of antimony (Sb) and tin (Sn) in virtually all paint samples. Antimony : The mean concentration of 31,379 ppm (over 3%) is exceptionally high. Antimony trioxide (Sb₂O₃) is used as a flame retardant synergist and opacifier. The consistent presence at such high levels suggests its intentional and substantial use. While there is no universally mandated limit for antimony in paint, the European Union's REACH regulation restricts its use in consumer articles to 0.1% (1000 ppm) for certain applications due to carcinogenicity concerns [ 19 ]. The levels found here are over 30 times this safety benchmark. A recent study from Pakistan also reported high antimony in paints (mean ~ 2,500 ppm) [ 20 ], but the concentrations in our study are an order of magnitude higher, indicating a more widespread and localized problem. Chronic exposure to antimony dust is linked to pneumoconiosis and cardiovascular issues, and the International Agency for Research on Cancer (IARC) classifies antimony trioxide as a Group 2B carcinogen (possibly carcinogenic to humans) [ 21 ]. Tin : The high concentrations of tin (mean 35,896 ppm) are equally concerning. While there are no specific limits for total tin, the presence of such high levels raises concerns about the potential presence of organotin compounds (tributyltin - TBT), which are highly regulated biocides due to their endocrine-disrupting properties [ 13 , 23 ]. The use of TBT in antifouling paints is banned globally under the International Convention on the Control of Harmful Anti-fouling Systems [ 22 ], and its use in consumer products is heavily restricted in many countries [ 23 ]. A 2022 review highlighted the ongoing environmental and health concerns from organotins, even in regions with bans, due to their persistence [ 24 ]. The levels detected in our study, although representing total tin rather than speciated forms, suggest a significant toxic metal burden that warrants further investigation into its chemical form and bioavailability. 4.3. Arsenic and Potential Combined Effects." The presence of arsenic at levels up to 4,355 ppm in some samples further compounds the health risk. Arsenic is a Class I human carcinogen. The US CPSC limits arsenic in consumer products to a negligible migration level, effectively banning its intentional use [ 25 ]. The detected level of 4,355 ppm is extraordinarily high and indicates serious contamination. Cadmium was found at low levels, which is consistent with its phased use in pigments. The detection of this multi-toxicant "cocktail" (Pb, Sb, Sn, As) is a major public health concern. The combined neurotoxic, carcinogenic, and endocrine-disrupting effects of these elements could lead to synergistic or additive health impacts, significantly amplifying the risk for children, who are most vulnerable to such chemical mixtures [ 11 , 26 ]. Recent studies have highlighted the importance of such mixture assessments in environmental health. [ 27 ]. 4.4. Public Health Implications and the Role of Multi-Elemental XRF Screening This study demonstrates the critical advantage of using a multi-elemental technique like XRF for public health surveillance. A singular focus on lead would have completely missed the significant threat from antimony and tin. XRF provides a cost-effective tool for regulatory bodies to conduct holistic market surveillance and enforce comprehensive safety standards. However, it is important to note that XRF provides total elemental concentrations and cannot determine chemical speciation, which is crucial for fully assessing the toxicity and bioavailability of elements like tin and arsenic. Future studies should incorporate speciation analysis to better characterize the health risks. 4.5. Study Limitations and Future Research This study has limitations. The sample size, while representative, could be expanded in future nationwide surveys. XRF provides total elemental concentration and does not specify the chemical form (speciation), which is critical for determining the bioavailability and toxicity of elements like tin (organic vs. inorganic) and arsenic (As³⁺ vs. As⁵⁺). Future research should incorporate speciation analysis and bio accessibility studies (using simulated lung or gastric fluids) to better understand the actual health risk. Furthermore, correlating the levels of these metals in paints with biomarkers of exposure in vulnerable populations would provide direct evidence of the health impact. 5. CONCLUSION AND RECOMMENDATIONS This study utilized EDXRF spectroscopy to provide an unprecedented multi-elemental profile of paints and their raw materials in Southwestern Nigeria. The results paint a dire picture: commercially available paints are heavily contaminated with a cocktail of toxic metals. The pervasive and high levels of lead confirm a persistent and widespread non-compliance with safety standards. The newly identified and alarmingly high concentrations of antimony and tin reveal a broader, previously underappreciated toxicological threat that extends beyond lead. The following actions are urgently recommended: Immediate Regulatory Enforcement : The Standards Organization of Nigeria (SON) must rigorously and publicly enforce the existing mandatory standard (NIS 269:2017) that sets a 90 ppm limit for lead in paints. Non-compliant products must be removed from the market. Expansion of Regulatory Frameworks : Regulatory standards must be expanded to include mandatory limits for other toxic metals, particularly antimony, tin, and arsenic, in paint formulations. A total lead limit of 90 ppm should be the starting point, not the end goal. Supply Chain Intervention : Regulatory efforts must target the source by mandating the certification of raw materials. Importers and local suppliers of pigments, driers, and other additives must provide evidence of low heavy metal content. Public and Industry Awareness : A nationwide campaign should be launched to educate manufacturers, retailers, painters, and the general public about the widespread health risks of toxic metals in paints and to promote consumer demand for safer, third-party certified products. Adoption of Advanced Screening : Regulatory agencies should adopt XRF technology for rapid and cost-effective market surveillance to ensure compliance. Safeguarding the health of the Nigerian population, particularly its children, from preventable chemical exposure requires decisive and evidence-based action. Addressing this multi-elemental contamination in paints is a critical and achievable step towards that goal. Declarations Clinical Trial Number Not applicable. Ethics Approval: Not applicable. Consent to Participate: Not applicable Consent for Publication: Not applicable. Funding: This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. Author Contribution Peter T. Osuolale: Conceptualization, Methodology, Formal Analysis, Software, Data Curation, Writing – Original Draft.Prof. J. O. Ojo: Project Administration, Supervision, Writing – Review & Editing.Danjuma D. Maza: Supervision, Validation, Writing – Review & Editing.Grace O. Akinlade: Resources, Writing – Review & Editing.Abayomi M. Olaosun: Validation, Writing – Review & Editing, Visualization.Alade Adetomiwa Adebayo: Resources, Writing – Review & Editing.Tolulope Karaotose: Writing – Review & Editing.Sylvester Jesse: Writing – Review & Editing. Data Availability The datasets generated and analyzed during the current study are available from the corresponding author on reasonable request. All relevant data supporting the findings of this study are included within the manuscript and its supplementary materials. References Prüss-Ustün A, Vickers C, Haefliger P, Bertollini R. Knowns and unknowns on burden of disease due to chemicals: a systematic review. 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International Agency for Research on Cancer (IARC). IARC Monographs on the Identification of Carcinogenic Hazards to Humans, Volume 121: Antimony Trioxide and Some Antimony Trioxide Compounds. World Health Organization; 2019. International Maritime Organization (IMO). (2001). International Convention on the Control of Harmful Anti-fouling Systems on Ships. Kannan K, Tanabe S. Organotin compounds in the environment: an overview. Reviews of Environmental Contamination and Toxicology. New York, NY: Springer; 2009. pp. 1–50. Li Z, Li R, Zhou J. A review of the environmental occurrence, effects, and mitigation strategies for organotin compounds. Sci Total Environ. 2022;807:150856. U.S. Consumer Product Safety Commission (CPSC). (2009). 16 C.F.R. Part 1303 – Ban of Lead-Containing Paint and Certain Consumer Products Bearing Lead-Containing Paint (Arsenic provision). Carpenter DO, Arcaro K, Spink DC. Understanding the human health effects of chemical mixtures. Environ Health Perspect. 2002;110(suppl 1):25–42. Ustaoğlu F, Yüksel B, Yazman MM, Jaskuła J, Tokatlı C. Chemometric investigation of river system contamination: Source identification and risk assessment using positive matrix factorization and Monte Carlo simulation. J Contam Hydrol. 2025;273:104627. Additional Declarations No competing interests reported. Supplementary Files SupplementaryMaterialsDPH.docx Cite Share Download PDF Status: Posted Version 1 posted 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. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-8995080","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":610927257,"identity":"f83c5f38-01eb-4793-a011-1a3c711e4db0","order_by":0,"name":"Peter Taiwo 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University","correspondingAuthor":false,"prefix":"","firstName":"Jesse","middleName":"","lastName":"Sylvester","suffix":""}],"badges":[],"createdAt":"2026-02-28 11:54:21","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-8995080/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-8995080/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":105432923,"identity":"f2c0a166-f5c4-499f-9484-49103e774f72","added_by":"auto","created_at":"2026-03-26 02:57:15","extension":"jpg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":95048,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eCalibration Curve for Lead using XRF\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"Picture1.jpg","url":"https://assets-eu.researchsquare.com/files/rs-8995080/v1/7c55d9272c069081fcb54617.jpg"},{"id":105432925,"identity":"64e15d9c-a47a-4973-81c0-f410f74172af","added_by":"auto","created_at":"2026-03-26 02:57:16","extension":"jpg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":27197,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eA Typical XRF Spectrum of Sedem Paint\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"Picture2.jpg","url":"https://assets-eu.researchsquare.com/files/rs-8995080/v1/c3c89a2d514b967fcd981448.jpg"},{"id":105432926,"identity":"db5b65fa-999a-4c35-b3fd-9fdec7e8a012","added_by":"auto","created_at":"2026-03-26 02:57:16","extension":"jpg","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":13579,"visible":true,"origin":"","legend":"\u003cp\u003eBoxplot of Toxic Metal Concentrations in Paint Samples (Red dashed line indicates the 90-ppm Pb limit)\u003c/p\u003e","description":"","filename":"Picture3.jpg","url":"https://assets-eu.researchsquare.com/files/rs-8995080/v1/e0bc510a1aa5170ecae5c061.jpg"},{"id":108657680,"identity":"9df0b11e-1020-44a2-9a0e-7b8c0bd3bbf8","added_by":"auto","created_at":"2026-05-07 04:10:39","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":403848,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8995080/v1/30e3ae7a-6ffe-45f0-b6c3-82760141eaad.pdf"},{"id":105565939,"identity":"cf269a26-17ba-41d6-bf4d-916b9f68f2fa","added_by":"auto","created_at":"2026-03-27 12:54:49","extension":"docx","order_by":0,"title":"","display":"","copyAsset":false,"role":"supplement","size":27401,"visible":true,"origin":"","legend":"","description":"","filename":"SupplementaryMaterialsDPH.docx","url":"https://assets-eu.researchsquare.com/files/rs-8995080/v1/27cccd0914f76acfbae5bacd.docx"}],"financialInterests":"No competing interests reported.","formattedTitle":"Multi-Elemental Analysis of Lead, Antimony, and Tin in Household Paints and Raw Materials in Southwestern Nigeria","fulltext":[{"header":"1. INTRODUCTION","content":"\u003cp\u003eThe global burden of disease attributable to toxic metal exposure is a major public health concern, with children being disproportionately affected [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. Lead exposure, in particular, has been described as a \"silent pandemic,\" causing an estimated 900,000 premature deaths annually and long-term neurodevelopmental damage in children who survive [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. Despite its well-documented toxicity, lead remains a persistent hazard, especially in low- and middle-income countries (LMICs) where regulatory frameworks are often weak or poorly enforced [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eA primary source of lead exposure in these settings is lead-based paint [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. As paint deteriorates over time, it chips and chalks, contaminating household dust and soil. Children, through their natural hand-to-mouth behavior, are at the highest risk of ingesting this contaminated dust, leading to elevated blood lead levels (BLLs) associated with irreversible cognitive deficits, reduced educational attainment, and increased behavioral problems [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eWhile the lead paint crisis in Nigeria has been previously noted [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e], the public health narrative has remained narrowly focused on this single element. This singular focus risks overlooking a potentially more significant threat: the \"cocktail effect\" of simultaneous exposure to multiple toxic elements [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. Elements like antimony (Sb), a possible human carcinogen linked to respiratory and cardiovascular issues [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e], and tin (Sn), whose organic compounds are potent endocrine disruptors [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e], are commonly used in paint formulations as flame retardants, biocides, and opacifiers. Their health impacts, particularly in combination with lead, are not well characterized but represent a critical gap in environmental health risk assessment.\u003c/p\u003e \u003cp\u003eThis study aims to bridge this gap by providing a public health-oriented assessment of toxic metal exposure from paints in Southwestern Nigeria. We employ X-ray Fluorescence (XRF) spectroscopy not as the study's centerpiece, but as a tool to generate evidence for public health action. Our objectives are:\u003c/p\u003e \u003cp\u003e \u003col\u003e \u003cspan\u003e \u003cli\u003e \u003cp\u003eTo quantify the concentrations of lead and other toxic metals (Sb, Sn, As, Cd) in commercially available paints.\u003c/p\u003e \u003c/li\u003e \u003c/span\u003e \u003cspan\u003e \u003cli\u003e \u003cp\u003eTo assess the level of compliance with international safety standards and identify sources of contamination in the supply chain.\u003c/p\u003e \u003c/li\u003e \u003c/span\u003e \u003cspan\u003e \u003cli\u003e \u003cp\u003eTo provide evidence-based recommendations for policy reform, regulatory enforcement, and targeted public health interventions.\u003c/p\u003e \u003c/li\u003e \u003c/span\u003e \u003c/ol\u003e \u003c/p\u003e"},{"header":"2. MATERIALS AND METHODS","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003e2.1. Study Design and Sample Collection\u003c/h2\u003e \u003cp\u003eA cross-sectional market survey was conducted to obtain a representative sample of paints available to consumers in Southwestern Nigeria. We purposively collected 10 ready-to-use paint products from major retail markets in Lagos, Oyo, and Osun states. To trace the source of contamination, we also collected 10 raw materials used in local paint production from three major suppliers in Ibadan, Lagos, and Osun states, selected based on their prominence in the local paint manufacturing supply chain. This two-tiered approach allows for targeted public health interventions at both the manufacturing and retail levels. The brands, types, locations, and colors of the paint samples are detailed in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e.\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\u003eDescription of Paint Samples Analyzed by XRF\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"5\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eS/N\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eBrand Name\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eType of Paint\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eLocation\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eColor\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eApa coat\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eOil Paint\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eLagos\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eWhite\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eFine Coat\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eAluminum Paint\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eLagos\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eWhite\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eGalaxy\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003ePlastic Paint\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eOsun\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eOrange\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003ePerfect\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eOil Paint\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eOsun\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eCaramel\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003ePrincess\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eEnamel Paint\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eOyo\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eBlack\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eRadius\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eEnamel Paint\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eOsun\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eBlue\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eRainlux\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eOil Paint\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eOyo\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eWhite\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eRealux\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eEnamel Paint\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eLagos\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eBrown\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSedem\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eSynthetic Rubber\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eLagos\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eWhite\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e10\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eVila paint\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eSynthetic Rubber\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eOyo\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eWhite\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003e2.2. Elemental Analysis and Health Risk Benchmarking\u003c/h2\u003e \u003cp\u003eElemental analysis was performed using a calibrated Energy Dispersive X-ray Fluorescence (XRF) spectrometer. We focused our quantitative reporting on elements of public health concern: Lead (Pb), Antimony (Sb), Tin (Sn), Arsenic (As), and Cadmium (Cd). The health risk was benchmarked by comparing lead concentrations directly against the stringent U.S. Consumer Product Safety Commission (CPSC) standard of 90 ppm [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e], a widely accepted public health benchmark. The limits of detection (LOD) and quantification (LOQ) for the analyzed elements were as follows: Pb (LOD: 5 ppm, LOQ: 15 ppm), Sb (LOD: 10 ppm, LOQ: 30 ppm), Sn (LOD: 8 ppm, LOQ: 25 ppm), As (LOD: 3 ppm, LOQ: 10 ppm), Cd (LOD: 2 ppm, LOQ: 6 ppm).\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003e2.3. Sample Preparation\u003c/h2\u003e \u003cp\u003eSamples were prepared according to their physical state to ensure homogeneity and optimal analysis, minimizing matrix effects [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e].\u003c/p\u003e \u003cp\u003e \u003cul\u003e \u003cli\u003e \u003cp\u003e \u003cb\u003ePowdered Samples\u003c/b\u003e (calcium carbonate, titanium oxide, red oxide): These were homogenized using an agate mortar and pestle and then sieved through a 75 \u0026micro;m mesh to ensure uniform particle size. Approximately 5 grams of the homogenized powder were pressed into a 32-mm diameter pellet using a hydraulic press at a pressure of 10 tons for 2 minutes.\u003c/p\u003e \u003c/li\u003e \u003cli\u003e \u003cp\u003e \u003cb\u003eLiquid Samples\u003c/b\u003e (liquid paints, formalin, ammonium hydroxide): Approximately 2 mL of the well-shaken sample was pipetted into a specialized liquid sample holder. The holder was sealed with a 6 \u0026micro;m thick Mylar film to prevent leakage and evaporation while allowing low-energy X-ray transmission.\u003c/p\u003e \u003c/li\u003e \u003cli\u003e \u003cp\u003e \u003cb\u003eSolid/Gel Samples\u003c/b\u003e (resins, calgon): These were carefully cut or scooped to create a flat, uniform surface that completely covered the sample cup opening, ensuring infinite thickness for the X-ray beam.\u003c/p\u003e \u003c/li\u003e \u003c/ul\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec6\" class=\"Section2\"\u003e \u003ch2\u003e2.4. XRF Instrumentation and Analytical Procedure\u003c/h2\u003e \u003cp\u003eElemental analysis was performed at the National Agency for Science and Engineering Infrastructure (NASENI), Akure, Nigeria, using an Energy Dispersive X-ray Fluorescence (EDXRF) spectrometer (Model EDX3600B, Skyray Instrument). The instrument is equipped with a high-performance Rhodium (Rh) target X-ray tube and a high-resolution Silicon Drift Detector (SDD) with a resolution of \u0026lt;\u0026thinsp;140 eV at Mn Kα. The instrument can detect elements from Sodium (Na) to Uranium (U).\u003c/p\u003e \u003cdiv id=\"Sec7\" class=\"Section3\"\u003e \u003ch2\u003e2.4.1. Instrument Calibration and Quality Assurance\u003c/h2\u003e \u003cp\u003eThe spectrometer was calibrated using a suite of certified reference materials (CRMs) traceable to the National Institute of Standards and Technology (NIST). For quantitative analysis of lead, a specific calibration curve was established. Standards were prepared in-house by adding varying volumes (2, 4, 6, 8 mL) of a 1000 mg/L lead standard solution (AccuStandard) to 8g of high-purity, lead-free chalk powder. The mixtures were thoroughly homogenized, dried, and pressed into pellets, creating calibration points at approximately 250, 500, 750, and 1000 ppm. The linearity of the calibration curve was excellent (R\u0026sup2; = 0.999). A typical calibration curve is shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eQuality control measures included:\u003c/p\u003e \u003cp\u003e \u003cul\u003e \u003cli\u003e \u003cp\u003eAnalysis of a blank sample (chalk pellet) to check for contamination.\u003c/p\u003e \u003c/li\u003e \u003cli\u003e \u003cp\u003ePeriodic analysis of a CRM to verify analytical accuracy. The recovery for lead was between 92\u0026ndash;105%. Each sample was analyzed in triplicate, and the mean concentration was reported. The standard deviation (SD) reported in the tables represents the variation across different paint samples.\u003c/p\u003e \u003c/li\u003e \u003c/ul\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec8\" class=\"Section3\"\u003e \u003ch2\u003e2.4.2. Analysis Conditions\u003c/h2\u003e \u003cp\u003eThe analysis was conducted under an air atmosphere at room temperature (25\u0026thinsp;\u0026plusmn;\u0026thinsp;2\u0026deg;C). The operating conditions were optimized for the detection of mid-Z and high-Z elements (Pb, Sb, Sn). The parameters were as follows:\u003c/p\u003e \u003cp\u003e \u003cul\u003e \u003cli\u003e \u003cp\u003eVoltage: 40 keV, Current: 350 \u0026micro;A, Medium filter, Live Time: 300 seconds, Atmosphere: Air\u003c/p\u003e \u003c/li\u003e \u003c/ul\u003e \u003c/p\u003e \u003cp\u003eThe spectrum for each sample was acquired and processed using the instrument's dedicated software (EDXRF 3600B Software). The software automatically identified elements based on their characteristic X-ray peaks (Kα and Lα lines) and quantified their concentrations using the fundamental parameters method.\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv id=\"Sec9\" class=\"Section2\"\u003e \u003ch2\u003e2.5. Data Analysis\u003c/h2\u003e \u003cp\u003eThe acquired quantitative data were exported to Microsoft Excel 365 and SPSS Statistics (Version 28) for statistical analysis. Descriptive statistics (mean, median, standard deviation, minimum, and maximum) were calculated for the concentrations of all detected elements. The results for toxic metals were compared against established regulatory limits, primarily the U.S. CPSC standard of 90 ppm for lead in paint.\u003c/p\u003e \u003c/div\u003e"},{"header":"3. RESULTS","content":"\u003cdiv id=\"Sec11\" class=\"Section2\"\u003e \u003ch2\u003e3.1. Multi-Elemental Composition Panorama\u003c/h2\u003e \u003cp\u003eThe EDXRF analysis detected a total of 27 elements across the twenty samples. Elements consistently below the detection limit in all samples (Na, Mg, etc.) have been omitted from the main tables for clarity. The full detailed tables are available in the Supplementary Material. The elemental assessment revealed significant diversity in composition, reflecting the varied formulations of different paint types and raw materials.\u003c/p\u003e \u003cp\u003eTitanium (Ti) was found at the highest concentration, reaching 598,464 ppm in a titanium oxide raw material sample, consistent with its use as a primary white pigment. Other major elements included Calcium (Ca) from extenders like calcium carbonate (max: 248,135 ppm), and Iron (Fe) from pigments like red and yellow oxide (max: 540,466 ppm). A typical XRF spectrum from a paint sample (Sedem Paint) is shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e, illustrating the multiple elemental peaks detected.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec12\" class=\"Section2\"\u003e \u003ch2\u003e3.2. Concentrations of Key Toxic Metals in Paints\u003c/h2\u003e \u003cp\u003eThe concentrations of the five toxic metals of primary public health concern in the twenty paint samples are detailed in Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e and visualized in Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eSummary of Toxic Metal Concentrations in Paint Samples\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=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" 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\"\u003e \u003cp\u003eMetal\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMinimum\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eMaximum\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eMean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eMedian\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003e% Samples\u0026thinsp;\u0026gt;\u0026thinsp;90 ppm (Pb)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePb\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e81\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e4,637\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e1,086\u0026thinsp;\u0026plusmn;\u0026thinsp;1,566\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e189\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e90%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAs\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e4,355\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e604\u0026thinsp;\u0026plusmn;\u0026thinsp;1,302\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u0026ndash;\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCd\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.4\u0026thinsp;\u0026plusmn;\u0026thinsp;0.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u0026ndash;\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSb\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e23,134\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e38,434\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e31,379\u0026thinsp;\u0026plusmn;\u0026thinsp;4,674\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e33,911\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u0026ndash;\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSn\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e28,610\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e43,812\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e35,896\u0026thinsp;\u0026plusmn;\u0026thinsp;4,485\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e36,797\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u0026ndash;\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"6\"\u003e\u003cem\u003eNote: SD represents variation across different paint samples.\u003c/em\u003e\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003cul\u003e \u003cli\u003e \u003cp\u003e \u003cb\u003eLead (Pb)\u003c/b\u003e: All paint samples contained detectable lead. The concentration ranged from 81 ppm to 4,637 ppm, with a mean concentration of 1,086 ppm and a median of 189 ppm. A staggering 90% of the paint samples exceeded the 90 ppm regulatory limit. The highest concentrations were found in synthetic rubber and enamel paints.\u003c/p\u003e \u003c/li\u003e \u003cli\u003e \u003cp\u003e \u003cb\u003eArsenic (As)\u003c/b\u003e: Arsenic was detected in 8 samples (31%). Concentrations ranged from below the detection limit to 4,355 ppm (Vila paint). The mean concentration across all samples was 604 ppm.\u003c/p\u003e \u003c/li\u003e \u003cli\u003e \u003cp\u003e \u003cb\u003eCadmium (Cd)\u003c/b\u003e: Cadmium was detected in only 4 samples at very low levels, ranging from 0 to 2 ppm. The mean concentration was 0.4 ppm.\u003c/p\u003e \u003c/li\u003e \u003cli\u003e \u003cp\u003e \u003cb\u003eAntimony (Sb)\u003c/b\u003e: Antimony was detected in all paint samples at exceptionally high concentrations, ranging from 23,134 ppm to 38,434 ppm, with a mean of 31,379 ppm and little variation (SD\u0026thinsp;=\u0026thinsp;4,674 ppm), suggesting its consistent use as an additive.\u003c/p\u003e \u003c/li\u003e \u003cli\u003e \u003cp\u003e \u003cb\u003eTin (Sn)\u003c/b\u003e: Tin was also detected in all paint samples at high concentrations, ranging from 28,610 ppm to 43,812 ppm, with a mean of 35,896 ppm.\u003c/p\u003e \u003c/li\u003e \u003c/ul\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec13\" class=\"Section2\"\u003e \u003ch2\u003e3.3. Source Apportionment: Toxic Metals in Input Raw Materials\u003c/h2\u003e \u003cp\u003eThe analysis of raw materials (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e) provided insights into potential sources of contamination.\u003c/p\u003e \u003cp\u003e \u003cul\u003e \u003cli\u003e \u003cp\u003e \u003cb\u003eLead (Pb)\u003c/b\u003e: The highest lead concentrations among raw materials were found in color pigments: Yellow Oxide (178 ppm) and Red Oxide (174 ppm). This indicates that these colorants are a primary source of lead contamination in the final paint products.\u003c/p\u003e \u003c/li\u003e \u003cli\u003e \u003cp\u003e \u003cb\u003eAntimony (Sb) and Tin (Sn)\u003c/b\u003e: Raw materials like Calgon (Sb: 36,676 ppm; Sn: 39,335 ppm) and Polyvinyl Acetate (PVA) (Sb: 36,255 ppm; Sn: 41,608 ppm) showed extremely high levels. This suggests that these materials, likely used as dispersants or binders, are major contributors of Sb and Sn in the locally produced paints.\u003c/p\u003e \u003c/li\u003e \u003cli\u003e \u003cp\u003e \u003cb\u003eTitanium Oxide\u003c/b\u003e, a common white pigment, contained 83 ppm of lead, demonstrating that even base materials can be contaminated.\u003c/p\u003e \u003c/li\u003e \u003c/ul\u003e \u003c/p\u003e \u003c/div\u003e"},{"header":"4. DISCUSSION","content":"\u003cp\u003eThis study provides a multi-elemental assessment of metals in household paints in Southwestern Nigeria. By employing this approach, we have confirmed widespread non-compliance with lead standards and identified elevatead concentrations of antimony and tin.\u003c/p\u003e \u003cdiv id=\"Sec15\" class=\"Section2\"\u003e \u003ch2\u003e4.1. Widespread Lead Contamination: A Persistent Crisis\u003c/h2\u003e \u003cp\u003eThe findings of this study unequivocally confirm a widespread non-compliance with safety standards and ongoing lead paint crisis in Nigeria. The mean lead concentration of 1,086 ppm is more than twelve times the 90 ppm US CPSC limit [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e] and significantly higher than the 600 ppm total lead limit stipulated in the Nigerian Industrial Standard (NIS 269:2017) [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]. This level of non-compliance (90% of samples) is consistent with recent studies from other LMICs. For instance, a 2023 analysis of paints from Uganda found a mean lead concentration of 4,900 ppm, with 67% of samples exceeding 90 ppm [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]. Similarly, a 2021 study in Kenya reported that 74% of paints violated the 90 ppm standard, with some samples containing over 15,000 ppm lead [\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]. Our results, showing a mean of 1,086 ppm, fit within this troubling global pattern of regulatory failure in LMICs, underscoring that lead-based paints remain the norm rather than the exception in many markets. The high lead levels in raw pigments confirm that the contamination originates early in the supply chain, necessitating interventions at the point of import and local production.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec16\" class=\"Section2\"\u003e \u003ch2\u003e4.2. High Levels Concentrations of Antimony and Tin\u003c/h2\u003e \u003cp\u003eA key finding of this study is the high concentrations of antimony (Sb) and tin (Sn) in virtually all paint samples.\u003c/p\u003e \u003cp\u003e \u003cul\u003e \u003cli\u003e \u003cp\u003e \u003cb\u003eAntimony\u003c/b\u003e: The mean concentration of 31,379 ppm (over 3%) is exceptionally high. Antimony trioxide (Sb₂O₃) is used as a flame retardant synergist and opacifier. The consistent presence at such high levels suggests its intentional and substantial use. While there is no universally mandated limit for antimony in paint, the European Union's REACH regulation restricts its use in consumer articles to 0.1% (1000 ppm) for certain applications due to carcinogenicity concerns [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e]. The levels found here are over 30 times this safety benchmark. A recent study from Pakistan also reported high antimony in paints (mean\u0026thinsp;~\u0026thinsp;2,500 ppm) [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e], but the concentrations in our study are an order of magnitude higher, indicating a more widespread and localized problem. Chronic exposure to antimony dust is linked to pneumoconiosis and cardiovascular issues, and the International Agency for Research on Cancer (IARC) classifies antimony trioxide as a Group 2B carcinogen (possibly carcinogenic to humans) [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e].\u003c/p\u003e \u003c/li\u003e \u003cli\u003e \u003cp\u003e \u003cb\u003eTin\u003c/b\u003e: The high concentrations of tin (mean 35,896 ppm) are equally concerning. While there are no specific limits for total tin, the presence of such high levels raises concerns about the potential presence of organotin compounds (tributyltin - TBT), which are highly regulated biocides due to their endocrine-disrupting properties [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e, \u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e]. The use of TBT in antifouling paints is banned globally under the International Convention on the Control of Harmful Anti-fouling Systems [\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e], and its use in consumer products is heavily restricted in many countries [\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e]. A 2022 review highlighted the ongoing environmental and health concerns from organotins, even in regions with bans, due to their persistence [\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e]. The levels detected in our study, although representing total tin rather than speciated forms, suggest a significant toxic metal burden that warrants further investigation into its chemical form and bioavailability.\u003c/p\u003e \u003c/li\u003e \u003c/ul\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec17\" class=\"Section2\"\u003e \u003ch2\u003e4.3. Arsenic and Potential Combined Effects.\"\u003c/h2\u003e \u003cp\u003eThe presence of arsenic at levels up to 4,355 ppm in some samples further compounds the health risk. Arsenic is a Class I human carcinogen. The US CPSC limits arsenic in consumer products to a negligible migration level, effectively banning its intentional use [\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e]. The detected level of 4,355 ppm is extraordinarily high and indicates serious contamination. Cadmium was found at low levels, which is consistent with its phased use in pigments. The detection of this multi-toxicant \"cocktail\" (Pb, Sb, Sn, As) is a major public health concern. The combined neurotoxic, carcinogenic, and endocrine-disrupting effects of these elements could lead to synergistic or additive health impacts, significantly amplifying the risk for children, who are most vulnerable to such chemical mixtures [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e, \u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e]. Recent studies have highlighted the importance of such mixture assessments in environmental health. [\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e].\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec18\" class=\"Section2\"\u003e \u003ch2\u003e4.4. Public Health Implications and the Role of Multi-Elemental XRF Screening\u003c/h2\u003e \u003cp\u003eThis study demonstrates the critical advantage of using a multi-elemental technique like XRF for public health surveillance. A singular focus on lead would have completely missed the significant threat from antimony and tin. XRF provides a cost-effective tool for regulatory bodies to conduct holistic market surveillance and enforce comprehensive safety standards. However, it is important to note that XRF provides total elemental concentrations and cannot determine chemical speciation, which is crucial for fully assessing the toxicity and bioavailability of elements like tin and arsenic. Future studies should incorporate speciation analysis to better characterize the health risks.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec19\" class=\"Section2\"\u003e \u003ch2\u003e4.5. Study Limitations and Future Research\u003c/h2\u003e \u003cp\u003eThis study has limitations. The sample size, while representative, could be expanded in future nationwide surveys. XRF provides total elemental concentration and does not specify the chemical form (speciation), which is critical for determining the bioavailability and toxicity of elements like tin (organic vs. inorganic) and arsenic (As\u0026sup3;⁺ vs. As⁵⁺). Future research should incorporate speciation analysis and bio accessibility studies (using simulated lung or gastric fluids) to better understand the actual health risk. Furthermore, correlating the levels of these metals in paints with biomarkers of exposure in vulnerable populations would provide direct evidence of the health impact.\u003c/p\u003e \u003c/div\u003e"},{"header":"5. CONCLUSION AND RECOMMENDATIONS","content":"\u003cp\u003eThis study utilized EDXRF spectroscopy to provide an unprecedented multi-elemental profile of paints and their raw materials in Southwestern Nigeria. The results paint a dire picture: commercially available paints are heavily contaminated with a cocktail of toxic metals. The pervasive and high levels of lead confirm a persistent and widespread non-compliance with safety standards. The newly identified and alarmingly high concentrations of antimony and tin reveal a broader, previously underappreciated toxicological threat that extends beyond lead.\u003c/p\u003e \u003cp\u003eThe following actions are urgently recommended:\u003c/p\u003e \u003cp\u003e \u003col\u003e \u003cspan\u003e \u003cli\u003e \u003cp\u003e \u003cb\u003eImmediate Regulatory Enforcement\u003c/b\u003e: The Standards Organization of Nigeria (SON) must rigorously and publicly enforce the existing mandatory standard (NIS 269:2017) that sets a 90 ppm limit for lead in paints. Non-compliant products must be removed from the market.\u003c/p\u003e \u003c/li\u003e \u003c/span\u003e \u003cspan\u003e \u003cli\u003e \u003cp\u003e \u003cb\u003eExpansion of Regulatory Frameworks\u003c/b\u003e: Regulatory standards must be expanded to include mandatory limits for other toxic metals, particularly antimony, tin, and arsenic, in paint formulations. A total lead limit of 90 ppm should be the starting point, not the end goal.\u003c/p\u003e \u003c/li\u003e \u003c/span\u003e \u003cspan\u003e \u003cli\u003e \u003cp\u003e \u003cb\u003eSupply Chain Intervention\u003c/b\u003e: Regulatory efforts must target the source by mandating the certification of raw materials. Importers and local suppliers of pigments, driers, and other additives must provide evidence of low heavy metal content.\u003c/p\u003e \u003c/li\u003e \u003c/span\u003e \u003cspan\u003e \u003cli\u003e \u003cp\u003e \u003cb\u003ePublic and Industry Awareness\u003c/b\u003e: A nationwide campaign should be launched to educate manufacturers, retailers, painters, and the general public about the widespread health risks of toxic metals in paints and to promote consumer demand for safer, third-party certified products.\u003c/p\u003e \u003c/li\u003e \u003c/span\u003e \u003cspan\u003e \u003cli\u003e \u003cp\u003e \u003cb\u003eAdoption of Advanced Screening\u003c/b\u003e: Regulatory agencies should adopt XRF technology for rapid and cost-effective market surveillance to ensure compliance.\u003c/p\u003e \u003c/li\u003e \u003c/span\u003e \u003c/ol\u003e \u003c/p\u003e \u003cp\u003eSafeguarding the health of the Nigerian population, particularly its children, from preventable chemical exposure requires decisive and evidence-based action. Addressing this multi-elemental contamination in paints is a critical and achievable step towards that goal.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e \u003ch2\u003eClinical Trial Number\u003c/h2\u003e \u003cp\u003eNot applicable.\u003c/p\u003e \u003c/p\u003e\u003cp\u003e \u003ch2\u003eEthics Approval:\u003c/h2\u003e \u003cp\u003eNot applicable.\u003c/p\u003e \u003c/p\u003e \u003cp\u003e \u003cstrong\u003eConsent to Participate:\u003c/strong\u003e \u003cp\u003eNot applicable\u003c/p\u003e \u003c/p\u003e \u003cp\u003e \u003cstrong\u003eConsent for Publication:\u003c/strong\u003e \u003cp\u003eNot applicable.\u003c/p\u003e \u003c/p\u003e\u003ch2\u003eFunding:\u003c/h2\u003e \u003cp\u003eThis research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.\u003c/p\u003e\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003ePeter T. Osuolale: Conceptualization, Methodology, Formal Analysis, Software, Data Curation, Writing \u0026ndash; Original Draft.Prof. J. O. Ojo: Project Administration, Supervision, Writing \u0026ndash; Review \u0026amp; Editing.Danjuma D. Maza: Supervision, Validation, Writing \u0026ndash; Review \u0026amp; Editing.Grace O. Akinlade: Resources, Writing \u0026ndash; Review \u0026amp; Editing.Abayomi M. Olaosun: Validation, Writing \u0026ndash; Review \u0026amp; Editing, Visualization.Alade Adetomiwa Adebayo: Resources, Writing \u0026ndash; Review \u0026amp; Editing.Tolulope Karaotose: Writing \u0026ndash; Review \u0026amp; Editing.Sylvester Jesse: Writing \u0026ndash; Review \u0026amp; Editing.\u003c/p\u003e\u003ch2\u003eData Availability\u003c/h2\u003e\u003cp\u003eThe datasets generated and analyzed during the current study are available from the corresponding author on reasonable request. All relevant data supporting the findings of this study are included within the manuscript and its supplementary materials.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003ePr\u0026uuml;ss-Ust\u0026uuml;n A, Vickers C, Haefliger P, Bertollini R. Knowns and unknowns on burden of disease due to chemicals: a systematic review. Environ Health. 2011;10(1):9.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWorld Health Organization. (2021). \u003cem\u003eLead poisoning\u003c/em\u003e. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://www.who.int/news-room/fact-sheets/detail/lead-poisoning-and-health\u003c/span\u003e\u003cspan address=\"https://www.who.int/news-room/fact-sheets/detail/lead-poisoning-and-health\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAttina TM, Trasande L. 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U.S. Department of Health and Human Services; 2019.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eATSDR. Toxicological Profile for Tin. U.S. Department of Health and Human Services; 2005.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eU.S. Consumer Product Safety Commission (CPSC). 16 C.F.R. Part 1303 \u0026ndash; Ban of Lead-Containing Paint. and Certain Consumer Products Bearing Lead-Containing Paint; 2009.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eRouillon M, Taylor MP. Can field portable X-ray fluorescence (pXRF) produce high quality data for application in environmental contamination research? Environ Pollut. 2016;214:255\u0026ndash;64.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eStandards Organization of Nigeria (SON). NIS 269:2017 \u0026ndash; Standard for Emulsion and Gloss. 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A review of the environmental occurrence, effects, and mitigation strategies for organotin compounds. Sci Total Environ. 2022;807:150856.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eU.S. Consumer Product Safety Commission (CPSC). (2009). 16 C.F.R. Part 1303 \u0026ndash; Ban of Lead-Containing Paint and Certain Consumer Products Bearing Lead-Containing Paint (Arsenic provision).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eCarpenter DO, Arcaro K, Spink DC. Understanding the human health effects of chemical mixtures. Environ Health Perspect. 2002;110(suppl 1):25\u0026ndash;42.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eUstaoğlu F, Y\u0026uuml;ksel B, Yazman MM, Jaskuła J, Tokatlı C. Chemometric investigation of river system contamination: Source identification and risk assessment using positive matrix factorization and Monte Carlo simulation. J Contam Hydrol. 2025;273:104627.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Lead Poisoning, Child Health, Environmental Exposure, Household Products, Public Health Policy, Heavy Metals, Nigeria, Antimony","lastPublishedDoi":"10.21203/rs.3.rs-8995080/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8995080/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eLead exposure is a critical public health issue, with paint being a primary source in many low- and middle-income countries. However, the potential for concurrent exposure to other toxic elements in paints, such as antimony and tin, remains largely uninvestigated, representing a significant knowledge gap in risk assessment.\u003c/p\u003e \u003cp\u003eWe conducted a cross-sectional market survey in Southwestern Nigeria, analyzing 10 commercially available paint products and 10 raw materials using Energy Dispersive X-ray Fluorescence (XRF) spectroscopy. The results were benchmarked against international regulatory standards (90 ppm for lead). The findings were contextualized with data on child exposure behaviors from a related survey to assess potential health risks.\u003c/p\u003e \u003cp\u003eOur analysis revealed a widespread non-compliance with safety standards. A staggering 90% of paint samples exceeded the 90 ppm lead limit, with a mean concentration of 1,086 ppm. Alarmingly, we identified widespread and extreme contamination with other toxic elements: antimony (mean: 31,379 ppm) and tin (mean: 35,896 ppm) were present in all samples. Arsenic was detected in 31% of samples, with one sample containing 4,355 ppm. Source analysis identified pigments (Yellow/Red Oxide) and additives (Calgon, PVA) as primary contamination sources.\u003c/p\u003e \u003cp\u003eThe Nigerian population, particularly children, is exposed to a dangerous combination of toxic elements from paints. This study moves beyond the well-documented lead problem to highlight a broader, under-recognized threat from antimony and tin. There is recommendation for robust enforcement of existing lead paint laws and the immediate expansion of regulatory frameworks to include other toxic metals. Public health interventions must focus on supply chain regulation, consumer awareness, and the promotion of safer alternatives to mitigate this preventable health risk.\u003c/p\u003e","manuscriptTitle":"Multi-Elemental Analysis of Lead, Antimony, and Tin in Household Paints and Raw Materials in Southwestern Nigeria","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-03-26 02:57:11","doi":"10.21203/rs.3.rs-8995080/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"1967743a-121d-4d62-a87a-727eb5c6c97f","owner":[],"postedDate":"March 26th, 2026","published":true,"recentEditorialEvents":[{"type":"decision","content":"Rejected","date":"2026-05-07T04:01:51+00:00","index":"","fulltext":""}],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2026-05-07T04:09:48+00:00","versionOfRecord":[],"versionCreatedAt":"2026-03-26 02:57:11","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8995080","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8995080","identity":"rs-8995080","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}