title: Pathways of human exposure to cobalt in Katanga, a mining area of the D.R. Congo.
abstract: Human exposure biomonitoring in the African Copperbelt (Katanga, southern D.R. Congo) revealed elevated cobalt (Co) exposure in the general population. This study was designed to identify the Co exposure routes for the non-occupationally exposed population in that area. The concentration of Co was measured in environmental and urine samples collected in urban and rural communities close to metal mining and/or refining plants, villages near a lake receiving effluents from metal refining plants, and control rural areas without industrial pollution. Drinking water, uncooked food items (maize flour, washed vegetables, fish and meat), indoor and outdoor dust samples were collected at each location. A food questionnaire was used to estimate dietary Co intake for adults and children. Geometric mean urine-Co (U-Co) concentrations were 4.5-fold (adults) and 6.6-fold (children) higher in the polluted than in the control area, with U-Co values being intermediate in the lakeside area. Average Co concentrations in environmental samples differed 6-40-fold between these areas. U-Co was positively correlated with most environmental Co concentrations, the highest correlations being found with Co in drinking water, vegetables and fruit. Estimated average total Co intake for adults was 63 (±42) μg/day in the control area, 94 (±55) μg/day in the lakeside villages and 570 (±100) μg Co/day in the polluted areas. U-Co was significantly related to modelled Co intake (R(2)=0.48, adults and R(2)=0.47, children; log-log relationship). Consumption of legumes, i.e. sweet potato leaves (polluted) and cereals+fish (lakeside) was the largest contributor to Co intake in adults, whereas dust ingestion appeared to contribute substantially in children in the polluted area. In conclusion, dietary Co is the main source of Co exposure in the polluted area and Co is efficiently transferred from soil and water in the human food chain.
authors.affiliation: Veterinary and Agrochemical Research Centre (VAR), Leuvensesteenweg 17, B-3080 Tervuren, Belgium; Division Soil and Water Management, KU Leuven, Kasteelpark Arenberg 20, B-3001 Leuven, Belgium.
authors.forename: Karlien
authors.initials: K
authors.lastname: Cheyns
authors.affiliation: Unité de Toxicologie et Environnement, Ecole de Santé Publique, Faculté de Médecine, Université de Lubumbashi, People's Republic of Congo.
authors.forename: Célestin
authors.initials: C
authors.lastname: Banza Lubaba Nkulu
authors.affiliation: Unité de Toxicologie et Environnement, Ecole de Santé Publique, Faculté de Médecine, Université de Lubumbashi, People's Republic of Congo; Unité de Toxicologie et Environnement, Ecole de Santé Publique, Faculté de Médecine, Université de Kamina, People's Republic of Congo.
authors.forename: Léon Kabamba
authors.initials: LK
authors.lastname: Ngombe
authors.affiliation: Unité de Toxicologie et Environnement, Ecole de Santé Publique, Faculté de Médecine, Université de Lubumbashi, People's Republic of Congo.
authors.forename: Jimmy Ngoy
authors.initials: JN
authors.lastname: Asosa
authors.affiliation: Louvain Centre for Toxicology and Applied Pharmacology, Institut de Recherche Expérimentale et Clinique, Université Catholique de Louvain, Belgium.
authors.forename: Vincent
authors.initials: V
authors.lastname: Haufroid
authors.affiliation: Geodynamics and Mineral Resources, Royal Museum for Central Africa, Tervuren, Belgium.
authors.forename: Thierry
authors.initials: T
authors.lastname: De Putter
authors.affiliation: Occupational & Environmental Medicine, Department of Public Health and Primary Care, KU Leuven, Herestraat 49 (O&N 706), B-3000 Leuven, Belgium; Centre for Environmental Sciences, Hasselt University, Belgium.
authors.forename: Tim
authors.initials: T
authors.lastname: Nawrot
authors.affiliation: Unité de Toxicologie et Environnement, Ecole de Santé Publique, Faculté de Médecine, Université de Kamina, People's Republic of Congo.
authors.forename: Célestin Muleka
authors.initials: CM
authors.lastname: Kimpanga
authors.affiliation: Unité de Toxicologie et Environnement, Ecole de Santé Publique, Faculté de Médecine, Université de Lubumbashi, People's Republic of Congo.
authors.forename: Oscar Luboya
authors.initials: OL
authors.lastname: Numbi
authors.affiliation: Unité de Toxicologie et Environnement, Ecole de Santé Publique, Faculté de Médecine, Université de Lubumbashi, People's Republic of Congo.
authors.forename: Benjamin Kabyla
authors.initials: BK
authors.lastname: Ilunga
authors.affiliation: Occupational & Environmental Medicine, Department of Public Health and Primary Care, KU Leuven, Herestraat 49 (O&N 706), B-3000 Leuven, Belgium.
authors.forename: Benoit
authors.initials: B
authors.lastname: Nemery
authors.affiliation: Division Soil and Water Management, KU Leuven, Kasteelpark Arenberg 20, B-3001 Leuven, Belgium.
authors.forename: Erik
authors.initials: E
authors.lastname: Smolders
mesh_terms: D000328:Adult; D002648:Child; D003035:Cobalt / Q000032:analysis*; D015023:Democratic Republic of the Congo; D004391:Dust / Q000032:analysis; D004781:Environmental Exposure / Q000706:statistics & numerical data*; D004785:Environmental Pollutants / Q000032:analysis*; D005260:Female; D005506:Food Contamination / Q000032:analysis* / Q000706:statistics & numerical data; D006801:Humans; D008297:Male; D008906:Mining; D012987:Soil / Q000737:chemistry
chemical_list: D004391:Dust; D004785:Environmental Pollutants; D012987:Soil; D003035:Cobalt
keywords: Biomonitoring; Cobalt; Environmental pollution; Exposure estimation; Katanga; Urine cobalt