Academic Journal
Assessment of crop-specific heavy metal transfer and dietary exposure in fertilized tropical smallholder soils in Kaduna State Nigeria.
| Τίτλος: | Assessment of crop-specific heavy metal transfer and dietary exposure in fertilized tropical smallholder soils in Kaduna State Nigeria. |
|---|---|
| Συγγραφείς: | Olowomofe OG; Federal University, Oye Ekiti, Ekiti State, Nigeria. olawale.olowomofe@fuoye.edu.ng., Faweya BE; Ekiti State University, Ado Ekiti, Ekiti State, Nigeria. |
| Πηγή: | Environmental geochemistry and health [Environ Geochem Health] 2026 Oct 05; Vol. 48 (15). Date of Electronic Publication: 2026 Oct 05. |
| Τύπος έκδοσης: | Journal Article |
| Γλώσσα: | English |
| Στοιχεία περιοδικού: | Publisher: Kluwer Academic Publishers Country of Publication: Netherlands NLM ID: 8903118 Publication Model: Electronic Cited Medium: Internet ISSN: 1573-2983 (Electronic) Linking ISSN: 02694042 NLM ISO Abbreviation: Environ Geochem Health Subsets: MEDLINE |
| Imprint Name(s): | Publication: 1999- : Dordrecht : Kluwer Academic Publishers Original Publication: Kew, Surrey : Science and Technology Letters, 1985- |
| Ιατρικοί όροι (MeSH): | Metals, Heavy*/analysis , Metals, Heavy*/metabolism , Soil Pollutants*/analysis , Soil Pollutants*/metabolism , Crops, Agricultural*/chemistry , Crops, Agricultural*/metabolism , Dietary Exposure*/analysis , Fertilizers*/analysis , Food Contamination*/analysis, Zea mays/chemistry ; Manihot/chemistry ; Soil/chemistry ; Abelmoschus/chemistry ; Nigeria ; Environmental Monitoring ; Humans ; Tropical Climate ; Risk Assessment |
| Περίληψη: | Fertilizer-associated heavy metals may accumulate in edible crops, yet crop-specific transfer and dietary risks remain poorly characterized in tropical smallholder systems. This study quantified Pb, Cu, Fe, Zn, Cd and Ni in paired soil and edible tissues of okra, maize and cassava from fertilized farms across five locations in Kaduna State, Nigeria. Thirty paired samples were analysed by Flame AAS, and transfer factors, multivariate statistics and dietary risk indices were used to assess metal distribution, uptake and potential exposure. Mean soil concentrations were 20.54, 42.95, 3350.00, 116.47, 0.141 and 38.41 mg kg-1 for Pb, Cu, Fe, Zn, Cd and Ni, respectively, compared with 0.650, 15.83, 908.57, 50.07, 0.014 and 0.174 mg kg-1 in edible tissues. Maize showed greater Pb accumulation than cassava and okra, although Pb transfer remained low across all crops. Dietary screening yielded a THQ of 2.98 for maize, exceeding the non-carcinogenic screening threshold of 1 and driven mainly by Cu and Pb, while the combined Pb + Cd carcinogenic risk was highest in maize (3.17 × 10-5). Cassava also slightly exceeded the THQ threshold (1.07), whereas okra remained well below it (0.011). Overall, the findings identify maize and cassava as priority crops for continued monitoring of Cu and Pb in agricultural fields subject to routine fertilizer use. (© 2026. The Author(s), under exclusive licence to Springer Nature B.V.) |
| Competing Interests: | Declarations. Conflict of interests: The authors declare that they have no relevant financial or non-financial interests to disclose. Ethical approval: Not applicable. This study did not involve human participants, human data, human tissue, or animals. Consent to participate: Not applicable. Consent for publication: Not applicable. AI Declaration: During the preparation of this manuscript, the authors used ChatGPT to assist with language editing, sentence refinement, and improvement of readability. After using this tool, the authors carefully reviewed and edited the content as needed and take full responsibility for the final content of the manuscript. |
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| Contributed Indexing: | Keywords: Cassava; Fertilized soil; Heavy metals; Ingestion risk; Maize; Okra; Soil–crop transfer |
| Substance Nomenclature: | 0 (Metals, Heavy) 0 (Soil Pollutants) 0 (Fertilizers) 0 (Soil) |
| Entry Date(s): | Date Created: 20261005 Date Completed: 20261005 Latest Revision: 20261005 |
| Update Code: | 20261006 |
| DOI: | 10.1007/s10653-026-03521-0 |
| PMID: | 42832094 |
| Βάση Δεδομένων: | MEDLINE |
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| Items | – Name: Title Label: Title Group: Ti Data: Assessment of crop-specific heavy metal transfer and dietary exposure in fertilized tropical smallholder soils in Kaduna State Nigeria. – Name: Author Label: Authors Group: Au Data: <searchLink fieldCode="AU" term="%22Olowomofe+OG%22">Olowomofe OG</searchLink>; Federal University, Oye Ekiti, Ekiti State, Nigeria. olawale.olowomofe@fuoye.edu.ng.<br /><searchLink fieldCode="AU" term="%22Faweya+BE%22">Faweya BE</searchLink>; Ekiti State University, Ado Ekiti, Ekiti State, Nigeria. – Name: TitleSource Label: Source Group: Src Data: <searchLink fieldCode="JN" term="%228903118%22">Environmental geochemistry and health</searchLink> [Environ Geochem Health] 2026 Oct 05; Vol. 48 (15). <i>Date of Electronic Publication: </i>2026 Oct 05. – Name: TypePub Label: Publication Type Group: TypPub Data: Journal Article – Name: Language Label: Language Group: Lang Data: English – Name: TitleSource Label: Journal Info Group: Src Data: <i>Publisher: </i><searchLink fieldCode="PB" term="%22Kluwer+Academic+Publishers%22">Kluwer Academic Publishers </searchLink><i>Country of Publication: </i>Netherlands <i>NLM ID: </i>8903118 <i>Publication Model: </i>Electronic <i>Cited Medium: </i>Internet <i>ISSN: </i>1573-2983 (Electronic) <i>Linking ISSN: </i><searchLink fieldCode="IS" term="%2202694042%22">02694042 </searchLink><i>NLM ISO Abbreviation: </i>Environ Geochem Health <i>Subsets: </i>MEDLINE – Name: PublisherInfo Label: Imprint Name(s) Group: PubInfo Data: <i>Publication</i>: 1999- : Dordrecht : Kluwer Academic Publishers<br /><i>Original Publication</i>: Kew, Surrey : Science and Technology Letters, 1985- – Name: SubjectMESH Label: MeSH Terms Group: Su Data: <searchLink fieldCode="MM" term="%22Metals%2C+Heavy%22">Metals, Heavy*</searchLink>/<searchLink fieldCode="MM" term="%22Metals%2C+Heavy+analysis%22">analysis</searchLink> <br /><searchLink fieldCode="MM" term="%22Metals%2C+Heavy%22">Metals, Heavy*</searchLink>/<searchLink fieldCode="MM" term="%22Metals%2C+Heavy+metabolism%22">metabolism</searchLink> <br /><searchLink fieldCode="MM" term="%22Soil+Pollutants%22">Soil Pollutants*</searchLink>/<searchLink fieldCode="MM" term="%22Soil+Pollutants+analysis%22">analysis</searchLink> <br /><searchLink fieldCode="MM" term="%22Soil+Pollutants%22">Soil Pollutants*</searchLink>/<searchLink fieldCode="MM" term="%22Soil+Pollutants+metabolism%22">metabolism</searchLink> <br /><searchLink fieldCode="MM" term="%22Crops%2C+Agricultural%22">Crops, Agricultural*</searchLink>/<searchLink fieldCode="MM" term="%22Crops%2C+Agricultural+chemistry%22">chemistry</searchLink> <br /><searchLink fieldCode="MM" term="%22Crops%2C+Agricultural%22">Crops, Agricultural*</searchLink>/<searchLink fieldCode="MM" term="%22Crops%2C+Agricultural+metabolism%22">metabolism</searchLink> <br /><searchLink fieldCode="MM" term="%22Dietary+Exposure%22">Dietary Exposure*</searchLink>/<searchLink fieldCode="MM" term="%22Dietary+Exposure+analysis%22">analysis</searchLink> <br /><searchLink fieldCode="MM" term="%22Fertilizers%22">Fertilizers*</searchLink>/<searchLink fieldCode="MM" term="%22Fertilizers+analysis%22">analysis</searchLink> <br /><searchLink fieldCode="MM" term="%22Food+Contamination%22">Food Contamination*</searchLink>/<searchLink fieldCode="MM" term="%22Food+Contamination+analysis%22">analysis</searchLink><br /><searchLink fieldCode="MH" term="%22Zea+mays%22">Zea mays</searchLink>/<searchLink fieldCode="MH" term="%22Zea+mays+chemistry%22">chemistry</searchLink> ; <searchLink fieldCode="MH" term="%22Manihot%22">Manihot</searchLink>/<searchLink fieldCode="MH" term="%22Manihot+chemistry%22">chemistry</searchLink> ; <searchLink fieldCode="MH" term="%22Soil%22">Soil</searchLink>/<searchLink fieldCode="MH" term="%22Soil+chemistry%22">chemistry</searchLink> ; <searchLink fieldCode="MH" term="%22Abelmoschus%22">Abelmoschus</searchLink>/<searchLink fieldCode="MH" term="%22Abelmoschus+chemistry%22">chemistry</searchLink> ; <searchLink fieldCode="MH" term="%22Nigeria%22">Nigeria</searchLink> ; <searchLink fieldCode="MH" term="%22Environmental+Monitoring%22">Environmental Monitoring</searchLink> ; <searchLink fieldCode="MH" term="%22Humans%22">Humans</searchLink> ; <searchLink fieldCode="MH" term="%22Tropical+Climate%22">Tropical Climate</searchLink> ; <searchLink fieldCode="MH" term="%22Risk+Assessment%22">Risk Assessment</searchLink> – Name: Abstract Label: Abstract Group: Ab Data: Fertilizer-associated heavy metals may accumulate in edible crops, yet crop-specific transfer and dietary risks remain poorly characterized in tropical smallholder systems. This study quantified Pb, Cu, Fe, Zn, Cd and Ni in paired soil and edible tissues of okra, maize and cassava from fertilized farms across five locations in Kaduna State, Nigeria. Thirty paired samples were analysed by Flame AAS, and transfer factors, multivariate statistics and dietary risk indices were used to assess metal distribution, uptake and potential exposure. Mean soil concentrations were 20.54, 42.95, 3350.00, 116.47, 0.141 and 38.41 mg kg<superscript>-1</superscript> for Pb, Cu, Fe, Zn, Cd and Ni, respectively, compared with 0.650, 15.83, 908.57, 50.07, 0.014 and 0.174 mg kg<superscript>-1</superscript> in edible tissues. Maize showed greater Pb accumulation than cassava and okra, although Pb transfer remained low across all crops. Dietary screening yielded a THQ of 2.98 for maize, exceeding the non-carcinogenic screening threshold of 1 and driven mainly by Cu and Pb, while the combined Pb + Cd carcinogenic risk was highest in maize (3.17 × 10<superscript>-5</superscript>). Cassava also slightly exceeded the THQ threshold (1.07), whereas okra remained well below it (0.011). Overall, the findings identify maize and cassava as priority crops for continued monitoring of Cu and Pb in agricultural fields subject to routine fertilizer use.<br /> (© 2026. The Author(s), under exclusive licence to Springer Nature B.V.) – Name: Abstract Label: Competing Interests Group: Ab Data: Declarations. Conflict of interests: The authors declare that they have no relevant financial or non-financial interests to disclose. Ethical approval: Not applicable. This study did not involve human participants, human data, human tissue, or animals. Consent to participate: Not applicable. Consent for publication: Not applicable. AI Declaration: During the preparation of this manuscript, the authors used ChatGPT to assist with language editing, sentence refinement, and improvement of readability. 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World Health Organization. https://www.who.int/publications/i/item/9789241209601. – Name: SubjectMinor Label: Contributed Indexing Group: Data: <i>Keywords: </i>Cassava; Fertilized soil; Heavy metals; Ingestion risk; Maize; Okra; Soil–crop transfer – Name: NumberCAS Label: Substance Nomenclature Group: ID Data: 0 (Metals, Heavy)<br />0 (Soil Pollutants)<br />0 (Fertilizers)<br />0 (Soil) – Name: DateEntry Label: Entry Date(s) Group: Date Data: <i>Date Created: </i>20261005 <i>Date Completed: </i>20261005 <i>Latest Revision: </i>20261005 – Name: DateUpdate Label: Update Code Group: Date Data: 20261006 – Name: DOI Label: DOI Group: ID Data: 10.1007/s10653-026-03521-0 – Name: AN Label: PMID Group: ID Data: 42832094 |
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| RecordInfo | BibRecord: BibEntity: Identifiers: – Type: doi Value: 10.1007/s10653-026-03521-0 Languages: – Code: eng Text: English Subjects: – SubjectFull: Zea mays chemistry Type: general – SubjectFull: Manihot chemistry Type: general – SubjectFull: Soil chemistry Type: general – SubjectFull: Abelmoschus chemistry Type: general – SubjectFull: Nigeria Type: general – SubjectFull: Environmental Monitoring Type: general – SubjectFull: Humans Type: general – SubjectFull: Tropical Climate Type: general – SubjectFull: Risk Assessment Type: general – SubjectFull: Metals, Heavy analysis Type: general – SubjectFull: Metals, Heavy metabolism Type: general – SubjectFull: Soil Pollutants analysis Type: general – SubjectFull: Soil Pollutants metabolism Type: general – SubjectFull: Crops, Agricultural chemistry Type: general – SubjectFull: Crops, Agricultural metabolism Type: general – SubjectFull: Dietary Exposure analysis Type: general – SubjectFull: Fertilizers analysis Type: general – SubjectFull: Food Contamination analysis Type: general Titles: – TitleFull: Assessment of crop-specific heavy metal transfer and dietary exposure in fertilized tropical smallholder soils in Kaduna State Nigeria. Type: main BibRelationships: HasContributorRelationships: – PersonEntity: Name: NameFull: Olowomofe OG – PersonEntity: Name: NameFull: Faweya BE IsPartOfRelationships: – BibEntity: Dates: – D: 05 M: 10 Text: 2026 Oct 05 Type: published Y: 2026 Identifiers: – Type: issn-electronic Value: 1573-2983 Numbering: – Type: volume Value: 48 – Type: issue Value: 15 Titles: – TitleFull: Environmental geochemistry and health Type: main |
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