title: Distribution and accumulation of metals in tadpoles inhabiting the metalliferous streams of eastern Chalkidiki, northeast Greece.
abstract: The present study investigates the accumulation of heavy metals [copper (Cu), lead (Pb), zinc (Zn), magnesium (Mn), cadmium (Cd), nickel (Ni), and chromium (Cr)] in tadpoles inhabiting the metalliferous streams flowing within the Asprolakkas River basin (northeast Chalkidiki peninsula, Greece) and the effect of potentially harmful elements in stream water and sediment on the corresponding levels in their tissue. Animals were collected from six sampling sites influenced by a wide range of surface water and stream sediment trace element concentrations. The results of the chemical analyses showed that tadpoles accumulated significant levels of all of the examined metals. The range of whole-body mean measured concentrations were (in dry mass) as follows: Cu (46-182 mg/kg), Pb (103-4,490 mg/kg), Zn (494-11,460 mg/kg), Mn (1,620-13,310 mg/kg), Cd (1.2-82 mg/kg), Ni (57-163 mg/kg), and Cr (38-272 mg/kg). The mean concentrations of Pb, Zn, Mn, Ni, Cr, and Cd in Kokkinolakkas stream, which drains a currently active mining area, were the highest ever reported in tadpoles. Our results indicate that whole-body levels of Pb, Zn, Cu, and Cd increase with stream sediment concentrations and that these organisms tend to accumulate metals bound to Fe and Mn oxides. In addition, high dissolved concentrations and significant concentrations associated with more labile geochemical phases of sediments for specific metals were contributing factors determining whole-body levels. Given the observed bioconcentration factors, as well as the correlation with sediment concentrations, it is proposed that these organisms could be considered as bioindicators of environmental contamination and may be used for monitoring purposes within this metal-rich zone and, perhaps, within other rivers affected by metal mining.
authors.affiliation: Department of Geology and Geoenvironment, University of Athens, 157 84 Athens, Greece. kelepert@geol.uoa.gr
authors.forename: Efstratios
authors.initials: E
authors.lastname: Kelepertzis
authors.forename: Ariadne
authors.initials: A
authors.lastname: Argyraki
authors.forename: Efstratios
authors.initials: E
authors.lastname: Valakos
authors.forename: Emmanouil
authors.initials: E
authors.lastname: Daftsis
mesh_terms: D000818:Animals; D002104:Cadmium / Q000032:analysis / Q000378:metabolism; D004784:Environmental Monitoring; D019015:Geologic Sediments / Q000737:chemistry; D006115:Greece; D007814:Larva / Q000378:metabolism*; D007854:Lead / Q000032:analysis / Q000378:metabolism; D008670:Metals / Q000032:analysis / Q000378:metabolism*; D045483:Rivers / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000378:metabolism*; D015032:Zinc / Q000032:analysis / Q000378:metabolism
chemical_list: D008670:Metals; D014874:Water Pollutants, Chemical; D002104:Cadmium; D007854:Lead; D015032:Zinc