Spatial Variability, Bio-accumulation, and Health Risks of Heavy Metals in Wudil Agricultural Produce: Insights from MP-AES Quantification

Spatial Variability, Bio-accumulation, and Health Risks of Heavy Metals in Wudil Agricultural Produce: Insights from MP-AES Quantification | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Spatial Variability, Bio-accumulation, and Health Risks of Heavy Metals in Wudil Agricultural Produce: Insights from MP-AES Quantification Emmanuel Bernard, Ugwoke Augustina Oyibo, Mahmoud Bello Amina, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8467829/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract This study quantified heavy metals contamination in peri-urban agricultural soils and vegetables from Wudil, Kano State, Nigeria, using Microwave Plasma–Atomic Emission Spectroscopy (MP-AES, Agilent 4210). Concentrations of Pb, Cd, Cu, Zn, and Cr in soils ranged from 0.25 to 1.16 mg/kg, while vegetable concentrations varied between 0.08 and 11.03 mg/kg, reflecting distinct metal-specific uptake patterns. Manganese (Mn) exhibited the highest accumulation in vegetables (7.58–11.03 mg/kg; mean 9.11 mg/kg), particularly in lettuce, whereas Chromium (Cr) showed moderate variability (0.08–0.85 mg/kg). Cadmium (Cd) and Lead (Pb) concentrations in vegetables remained comparatively low (Cd: 0.02–0.19 mg/kg; Pb: 0.05–0.41 mg/kg), yet their toxicological relevance was evident in elevated Estimated Daily Intake (EDI) and Target Hazard Quotient (THQ) values. Although THQ values for individual metals were generally < 1, but cumulative Hazard Index (HI) values for some vegetables exceeded the safety threshold (ΣTHQ = 1.01–1.80). Cancer Risk (CR) estimates for Cd and Cr surpassed the acceptable limit of 10⁻⁴, with pepper (CR = 0.0180) and spinach (CR = 0.0124) presenting the highest carcinogenic risk. Despite moderate soil contamination (PLI = 0.44), vegetable uptake significantly amplified human-health risks. These findings highlight the need for continuous monitoring, improved wastewater-irrigation management, and targeted public-health interventions to reduce long-term dietary exposure. Estimated Daily Intake (EDI) Human health risk assessment Peri-urban agriculture Pollution Load Index (PLI) Soil–vegetable transfer Full Text Additional Declarations No competing interests reported. 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. 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-8467829","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":572788048,"identity":"ff16d5d7-30bd-466c-94c4-f689219d9e43","order_by":0,"name":"Emmanuel Bernard","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA5ElEQVRIiWNgGAWjYBACAwjFLAfEDSAWYwOxWoxhionXkthAtBZz9t5nD37usU7fzt7Y+OEHg43shgO8h1/g02LZc9zcsOdZeu7OnoPNkj0MacYbDvClWeB12I00NgmeA4dzN9xIbJBmYDicuOEAj5kBXi33n7FJ/jlwON3gRmLzbwaG/0RoucHGJg20JQGopQ1oywGQFuMH+P2SxiYtcyDdEOiXNsseg2TjmYd5zPDpAIbYMTbJNwes5c3Zmw/f+FFhJ9t3vMf4A149cBfCSWYGNgkStEAAM3G2jIJRMApGwUgBAGLDTHz/zLwiAAAAAElFTkSuQmCC","orcid":"","institution":"Nigeria Police Academy – Wudil, P. 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Quantification","fulltext":[],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":true,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":true,"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":"Estimated Daily Intake (EDI), Human health risk assessment, Peri-urban agriculture, Pollution Load Index (PLI), Soil–vegetable transfer","lastPublishedDoi":"10.21203/rs.3.rs-8467829/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8467829/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eThis study quantified heavy metals contamination in peri-urban agricultural soils and vegetables from Wudil, Kano State, Nigeria, using Microwave Plasma\u0026ndash;Atomic Emission Spectroscopy (MP-AES, Agilent 4210). Concentrations of Pb, Cd, Cu, Zn, and Cr in soils ranged from 0.25 to 1.16 mg/kg, while vegetable concentrations varied between 0.08 and 11.03 mg/kg, reflecting distinct metal-specific uptake patterns. Manganese (Mn) exhibited the highest accumulation in vegetables (7.58\u0026ndash;11.03 mg/kg; mean 9.11 mg/kg), particularly in lettuce, whereas Chromium (Cr) showed moderate variability (0.08\u0026ndash;0.85 mg/kg). Cadmium (Cd) and Lead (Pb) concentrations in vegetables remained comparatively low (Cd: 0.02\u0026ndash;0.19 mg/kg; Pb: 0.05\u0026ndash;0.41 mg/kg), yet their toxicological relevance was evident in elevated Estimated Daily Intake (EDI) and Target Hazard Quotient (THQ) values. Although THQ values for individual metals were generally\u0026thinsp;\u0026lt;\u0026thinsp;1, but cumulative Hazard Index (HI) values for some vegetables exceeded the safety threshold (ΣTHQ\u0026thinsp;=\u0026thinsp;1.01\u0026ndash;1.80). Cancer Risk (CR) estimates for Cd and Cr surpassed the acceptable limit of 10⁻⁴, with pepper (CR\u0026thinsp;=\u0026thinsp;0.0180) and spinach (CR\u0026thinsp;=\u0026thinsp;0.0124) presenting the highest carcinogenic risk. Despite moderate soil contamination (PLI\u0026thinsp;=\u0026thinsp;0.44), vegetable uptake significantly amplified human-health risks. These findings highlight the need for continuous monitoring, improved wastewater-irrigation management, and targeted public-health interventions to reduce long-term dietary exposure.\u003c/p\u003e","manuscriptTitle":"Spatial Variability, Bio-accumulation, and Health Risks of Heavy Metals in Wudil Agricultural Produce: Insights from MP-AES Quantification","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-01-12 20:42:33","doi":"10.21203/rs.3.rs-8467829/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":"2241b807-66ed-4322-8bf5-9276e3954f64","owner":[],"postedDate":"January 12th, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2026-01-23T16:10:19+00:00","versionOfRecord":[],"versionCreatedAt":"2026-01-12 20:42:33","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8467829","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8467829","identity":"rs-8467829","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}