Articles | Volume 22, issue 20
https://doi.org/10.5194/bg-22-5591-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/bg-22-5591-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| Highlight paper
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20 Oct 2025
Research article | Highlight paper |
| 20 Oct 2025
| 20 Oct 2025
Mercury contamination in staple crops impacted by artisanal and small-scale gold mining (ASGM): stable Hg isotopes demonstrate dominance of atmospheric uptake pathway for Hg in crops
Excellent O. Eboigbe
Dept. of Geological Sciences and Geological Engineering, Queens University, 36 Union St, Kingston ON, K7L3N6, Canada,
Nimelan Veerasamy
Dept. of Geological Sciences and Geological Engineering, Queens University, 36 Union St, Kingston ON, K7L3N6, Canada,
Abiodun M. Odukoya
Department of Geosciences, University of Lagos, G97X+XJC, Yaba, Oworonshoki, 101245, Lagos, Nigeria
Nnamdi C. Anene
Ministry of Solid Minerals Development, Government of Nigeria, P.M.B. 107, Luanda Crescent, Wuse II, Abuja, 904101, Federal Capital Territory, Nigeria
Jeroen E. Sonke
Géosciences Environnement Toulouse, CNRS/IRD/University of Toulouse, 14 Av. Edouard Belin, 31400, Toulouse, France
Sayuri Sagisaka Méndez
Department of Environmental Sciences, University of Toronto, 1265 Military Trail, Toronto, ON, M1C1A4, Canada
David S. McLagan
CORRESPONDING AUTHOR
Dept. of Geological Sciences and Geological Engineering, Queens University, 36 Union St, Kingston ON, K7L3N6, Canada,
School of Environmental Studies, Queen's University, 116 Barrie St, Kingston, ON, K7L3N6, Canada
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ASGM is rapidly expanding and Hg-use in the sector impacts agricultural system surrounding these spatially distributed activities. Contamination of crops from ASGM-derived Hg occurs via both uptake from both air and soil/water. In addition to risks to human consumers, Hg in staple crops can also be passed along to livestock/poultry further conflating risks. Research in this area requires interdisciplinary, collaborative, and adaptable approaches to improve our comprehension of these impacts.
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Co-editor-in-chief
The role of Artisanal Small-scale Gold Mining emissions and the uptake of Hg in biota are key research questions in global Hg cycling. The presented work focuses on an understudied region in Nigeria. It results from a successful international collaboration with local researchers from a region with high Artisanal Small-scale Gold Mining emissions and deserves the attention of the scientific community.
The role of Artisanal Small-scale Gold Mining emissions and the uptake of Hg in biota are key...
Short summary
Air, soil, and three common staple crops were assessed at an artisanal and small-scale gold mining (ASGM) processing site, and mercury (Hg) contamination was observed at a farm ≈ 500 m from the processing site. Of the crop tissues examined, foliage had the highest concentrations. Mercury stable isotopes indicate uptake of mercury from the air to the foliage as the dominant uptake pathway. Using typical dietary data for Nigerians, Hg intake from these crops was below reference dose levels and generally safe for consumption.
Air, soil, and three common staple crops were assessed at an artisanal and small-scale gold...
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