title: Distribution of trace elements in the aquatic ecosystem of the Thigithe river and the fish Labeo victorianus in Tanzania and possible risks for human consumption.
abstract: The aim of the present study was to assess the distribution of trace elements in the aquatic ecosystem of the Thigithe river. Samples of surface water, sediment and fish were collected up- and downstream of the North Mara Gold Mine (Tanzania) and following trace elements were analysed: As, Cd, Co, Cr, Cu, Hg, Ni, Pb and Zn. Trace element concentrations in surface water were below or near the detection limit. Regarding the sediments, relative high concentrations of arsenic at all sites and high levels of mercury at a site downstream of the mine where artisanal mining is performed were observed. Trace element concentrations in Ningu fish tissues (Labeo victorianus) were comparable to slightly higher than levels in fishes from unpolluted environments. For none of the measured human health risk by consumption of fish from the Thigithe river is expected when the Tanzanian average amount of 17 g/day is consumed. However, for Hg and As the advised maximum daily consumption of Ningu fish was lower than 100g. As a result fishermen and people living along the shores of the river consuming more fish than the average Tanzanian fish consumption set by the FAO (2005) are possibly at risk.
authors.affiliation: Laboratory of Systemic, Physiological and Ecotoxicological Research, Department of Biology, University of Antwerp, Groenenborgerlaan, 171 2020, Antwerp, Belgium; Department of Wildlife, Ministry of Natural Resources and Tourism, P.O. Box 1994, Dar es Salaam, Tanzania.
authors.forename: Gordian Rocky
authors.initials: GR
authors.lastname: Mataba
authors.affiliation: Laboratory of Systemic, Physiological and Ecotoxicological Research, Department of Biology, University of Antwerp, Groenenborgerlaan, 171 2020, Antwerp, Belgium.
authors.forename: Vera
authors.initials: V
authors.lastname: Verhaert
authors.affiliation: Laboratory of Systemic, Physiological and Ecotoxicological Research, Department of Biology, University of Antwerp, Groenenborgerlaan, 171 2020, Antwerp, Belgium.
authors.forename: Ronny
authors.initials: R
authors.lastname: Blust
authors.affiliation: Laboratory of Systemic, Physiological and Ecotoxicological Research, Department of Biology, University of Antwerp, Groenenborgerlaan, 171 2020, Antwerp, Belgium. Electronic address: lieven.bervoets@uantwerp.be.
authors.forename: Lieven
authors.initials: L
authors.lastname: Bervoets
mesh_terms: D000818:Animals; D003530:Cyprinidae / Q000378:metabolism*; D017753:Ecosystem; D004784:Environmental Monitoring; D005506:Food Contamination / Q000706:statistics & numerical data*; D006801:Humans; D045483:Rivers / Q000737:chemistry; D013636:Tanzania; D014131:Trace Elements / Q000032:analysis* / Q000378:metabolism; D014874:Water Pollutants, Chemical / Q000032:analysis* / Q000378:metabolism
chemical_list: D014131:Trace Elements; D014874:Water Pollutants, Chemical
keywords: Fish; Gold mining; Human health risk; Trace element