Airborne contamination by heavy metals and aluminum in the freshwater ecosystems of the Kola subarctic region (Russia) / Moiseenko T. I., Kudryavtseva L. P., Rodyushkin I. V. [et al.] // The Science of the Total Environment. - 1995. - Т. 160/161. - С. 715-727.

716 T.l. Moiseenko et al. / Sci. Total Environ. 160 /161 (1995) 715-727 Kola North lakes is substantially higher than that in other regions of the Subarctic and Arctic. Around the industrial centers, sulfate concentra­ tion in lakes exceeds 200 /requiv./l; the typical range of values for the Kola regions is 75-100 /xequiv./l. These values indicate that acidification of surface waters in Kola North catchments is related to the anthropogenic influx of sulfate (Moiseenko, 1991, 1992). The acidification of an aquatic area can cause an increase in concentration of the ionic forms of metals in fresh waters (Schindler et al., 1980; Campbell and Stokes, 1985; King et al., 1992). The dangers of water pollution by heavy metals and Al is widely known. Heavy metals and Al exert a direct toxic influence upon living organ­ isms and accumulate in them, leading to further negative consequences (Kaiser, 1980; Moore and Ramamoorthy, 1987; Moiseenko and Kudravt- seva, 1990; Moiseenko and Yakovlev 1990; New­ man and McIntosh 1991). The objectives of these investigations are to estimate levels of pollution by heavy metals and Al in fresh water ecosystems, acquire information on the accumulation of heavy metals and the resulting toxic effects, and to determine the levels at which concentrations are critical in Arctic and Subarctic waters of the Kola Peninsula. 2. Materials and methods The elements Ni, Cu, Zn, Mn, Sr, Cd, Se, Pb and Al were studied in freshwater systems with respect to the following: 1. To determine concentrations in the waters and sediments of small lakes that received atmospheric input. During late autumn and winter (1990-1993), 374 lakes were investi­ gated for water chemistry and 120 lakes for sediments. These lakes were selected because we suspected that, due to their proximity to emissions, they reflected the impacts of air­ borne contaminants. 2. To evaluate metal speciation in the water, including the dynamics of speciation during periods of flooding, and the characteristics of acidic episodes in the rivers. Daily monitoring of four streams, located along the pollution load gradient, made it possible to estimate the specific character and regularities of vari­ ous heavy metal and Al speciations during periods of acidic episodes in the rivers. Ac­ cording to the degree of heavy metal and Al pollution, the streams are defined as follows: Stream 1, 20 km from the Pechenganikel company; Stream 2, 30 km southwest of the Severonikel company; Stream 3, 40 km south of the Severonikel plant; Stream 4, 80 km east of the Pechenganikel plant. 3. To document the accumulation of metals in fish, including muscles, kidney, liver, gills, skeleton. Species included Coregonus lavare- tus L., Salvelinus alpimts L., Salmo trutta L., and Esox luceus L. Fish were caught with standard gillnet series, consisting of eight fleets, 10- to 45-mm bar mesh size (Rosseland et al., 1979). 4. To determine toxic effects in the heavily pol­ luted water bodies and specific fish patholo­ gies related to the impact of heavy metals. Pathological and morphological examinations were performed on the fish, and symptoms of diseases were recorded. Critical levels of metal concentration in water are calculated according to established regularities in the system: concentration in water -» organism accumulation -> % fish with speci­ fic pathology. Concentration of metals in the water was de­ termined by the atomic absorption method with flameless atomization. To determine metal speci­ ations, an analytical method was applied that included separating suspended and dissolved species by filtering water samples through the filter membrane (45-^m). Dissolved forms were subsequently divided chromatographically into ion-exchangeable (labile) and non-exchangeable (non-labile) forms using an ion exchanger (ion exchange resin Dowex-50W in NA + form). Sediments were analyzed using the extraction method of Buckley and Cranston (1971). Heavy metal contamination factor (C f ) values were cal­ culated as the quotient of concentrations from the uppermost 0-1 cm of sediment and the mean