Metal-contaminated potato crops and potential human health risk in Bolivian mining highlands.
This study assessed metals in irrigation water, soil and potato crops impacted by mining discharges, as well as potential human health risk in the high desert near the historic mining center of Potosí, Bolivia. Metal concentrations were compared with international concentration limit guidelines. In addition, an ingested average daily dose and minimum risk level were used to determine the hazard quotient from potato consumption for adults and children. Irrigation water maximum concentrations of Cd, Pb and Zn in mining-impacted sites were elevated 20- to 1100-fold above international concentration limit guidelines. Agricultural soils contained total metal concentrations of As, Cd, Pb and Zn that exceeded concentration limits in agricultural soil guidelines by 22-, 9-, 3- and 12-fold, respectively. Potato tubers in mining-impacted sites had maximum concentrations of As, Cd, Pb and Zn that exceeded concentration limits in commercially sold vegetables by 9-, 10-, 16- and fourfold, respectively. Using conservative assumptions, hazard quotients (HQ) for potatoes alone were elevated for As, Cd and Pb among children (range 1.1-71.8), in nearly all of the mining-impacted areas; and for As and Cd among adults (range 1.2-34.2) in nearly all of the mining-impacted areas. Only one mining-impacted area had a Pb adult HQ for potatoes above 1 for adults. Toxic trace elements in a major regional dietary staple may be a greater concern than previously appreciated. Considering the multitude of other metal exposure routes in this region, it is likely that total HQ values for these metals may be substantially higher than our estimates.
Centro de Investigación en Ciencias y Recursos GeoAgroAmbientales (CENIGAA), Cra 5 No. 10-38 Oficina 203, Neiva, Huila, Colombia. aegarridor@gmail.com.
Alan E
AE
Garrido
Saint Francis University Environmental Engineering Program, Center for Watershed Research & Service, 117 Evergreen Drive, Loretto, PA, 15940, USA.
William H J
WHJ
Strosnider
Epidemiology Division, Department of Public Health Sciences, Penn State Cancer Institute, Pennsylvania State University College of Medicine, 500 University Drive, Mail Code CH69, Hershey, PA, 17033, USA.
Robin Taylor
RT
Wilson
Gobierno Autónomo del Departamento de Potosí, Secretaría de Minería y Metalurgia, Plaza Simón Bolívar Edificio IV, Centenario Piso II, Potosí, Bolivia.
Janette
J
Condori
Center for Restoration of Ecosystems and Watersheds, School of Civil Engineering and Environmental Science, University of Oklahoma, 202 W. Boyd St., Norman, OK, 73019, USA.
Robert W
RW
Nairn
D000328:Adult; D057914:Agricultural Irrigation; D001151:Arsenic / Q000032:analysis / Q000633:toxicity; D001838:Bolivia; D002104:Cadmium / Q000032:analysis / Q000633:toxicity; D002648:Child; D018556:Crops, Agricultural / Q000737:chemistry* / Q000633:toxicity; D004784:Environmental Monitoring; D006801:Humans; D007854:Lead / Q000032:analysis / Q000633:toxicity; D019216:Metals, Heavy / Q000032:analysis* / Q000633:toxicity; D008906:Mining; D018570:Risk Assessment; D012989:Soil Pollutants / Q000032:analysis* / Q000633:toxicity; D011198:Solanum tuberosum / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000032:analysis* / Q000633:toxicity; D015032:Zinc / Q000032:analysis / Q000633:toxicity
D019216:Metals, Heavy; D012989:Soil Pollutants; D014874:Water Pollutants, Chemical; D002104:Cadmium; D007854:Lead; D015032:Zinc; D001151:Arsenic
Acid mine drainage; Agriculture; Hazard; Human health; Metalloid exposure; Rural community