Sandimirov S. Specific Features of Accumulation of Cu, Ni, Zn, Cd and Hg in Two Whitefish Coregonus lavaretus (L.). Morphs Inhabiting the Inari-Pasvik Lacustrine-Riverine System. Inland Water Biology. 2011, Vol. 4, №, p. 383-392.

SPECIFIC FEATURES OF ACCUMULATION OF Cu, Ni, Zn, Cd, AND Hg 385 Fig. 1. Schematic map of the study region at the Pasvik River: (1) sampling sites. determined using the cold vapor atomic absorption technique in a FIMS (PerkinElmer) with the samples dissolved 5 to 500 times, depending on the organ ana­ lyzed. The quality control of the analysis was performed with a simultaneous determination of the studied ele­ ments in the DORM-2 certified reference material (shark muscle tissue, Institute for National Measure­ ment Standards, Canada). Statistical processing was performed with an assessment of the statistical signifi­ cance of differences in HM accumulation: in fish organs, ecological morphs, and the distance between the waterbody and the source of pollution based on a t-test for independent variables. Upon a high variabil­ ity of studied parameters, a small size of group sam­ ples, and a high precision of analyses, all available val­ ues o f metal contents were considered. The results are presented as means, standard errors, and deviations, as well as limits and extreme values. The data process­ ing was performed using STATISTICA 8 software package. RESULTS Copper An analysis o f the levels of Cu accumulation for the whole study period revealed that the metal level in the gill of both whitefish morphs gradually decreases the further the waterbody under study is from the source of pollution. The highest levels of metals were found in the fish from Lake Kuetsjarvi: <8 ^g/g in whitefish gill and muscles. The highest mean levels of Cu accumu­ lation were found in kidney (up to 16.41 ^g/g) and liver (up to 70 ^g/g in the medium-rakered and up to 42 ^g/g in sparsely rakered morphs) (Table 2). In gen­ eral, the intensity of Cu accumulation in two morphs INLAND WATER BIOLOGY Vol. 4 No. 3 2011