SURVEY OF TRACE-ELEMENTS IN LAKE WATERS OF FINNISH LAPLAND USING THE ICP-MS TECHNIQUE

Water samples for trace element analyses (Cd, Pb, As, Ni, Cu, Cr, Zn, Al) were collected from small Finnish headwater lakes in 1992 in conne ction with the national monitoring program on, long-range transboundar y air pollution (LRTAP) and surface water acidification. The lakes wer e situated all over the country, mainly in acid-sensitive upland areas . Data from this survey are compared with data from earlier surveys an d the differences between northern Finland and other parts of the coun try are highlighted. Mean trace element concentrations were significan tly lower for Cd, As, Zn and Ni in lakes in Lapland, compared with sim ilar lakes in central and southern Finland, and reflected the pattern of atmospheric deposition. Chromium, with lowest concentrations in the south, showed similarities to the recent atmospheric load. No clear d ifferences between areas were observed in concentrations of Pb and Cu. Concentration levels of trace elements in lakes in Lapland were simil ar to those in northern Sweden and close to the proposed background va lues. Element concentrations in Lapland correlated with lakewater acid ity (Cd, Zn, As P < 0.001) and with the concentration of total organic carbon (TOC) (Cr P < 0.001, Ni P < 0.01).