Ecotoxicological assessment of water quality and ecosystem health: a case study of the Volga river / Moiseenko T. I., Gashkina N. A., Sharova Yu. N., Kudryavtseva L. P. // Ecotoxicology and Environmental Safety. - 2008. - Т. 71, № 3. - С. 837-850.

Table 1 Concentration of microelements and their MPC values (;ig/l) and also pH, conductivity {/), calcium in water of Volga River 840 T.I. Moiseenko et al. / Ecotoxicology and Environmental Safety 71 (2008) 837-850 Parameter, element Upper Volga Middle Volga Lower Volga MPC X Min-Max X Min-Max X Min-Max pH 7.7 7.5-7.9 6.8 6.2-7.0 7.4 6.8-8.0 X (uSm/sm) 195 165-268 255 226-280 364 357-387 Ca (mg/1) 29 25-40 36 32-38 35 32-37 Hg <0.05 - <0.05 - <0.05 - 0.01 Cd 0.13 0.08-0.20 0.13 <0.02-0.62 0.13 0.02-0.26 5 Pb 0.46 0.02-0.80 <0.02 - 1.72 1.00-3.20 6 Al 272.3 190-400 31.7 8.20-70.9 820.5 440-1480 300 Sr 101.1 85.0-120 190.8 95.7-289 521.3 469-568 400 Ni 1.78 1.20-2.50 1.72 <0.5-5.58 2.22 1.60-3.30 10 Mn 101.6 72.0-150 62.4 12.9-111 27.7 22.7-35.7 10 Zn 3.73 1.30-5.40 1.36 <1-5.11 5.58 2.60-8.70 10 Cu 2.14 1.20-3.80 2.21 0.94-5.68 1.70 1.30-2.30 1 Cr 0.83 0.29-1.70 0.75 0.49-1.18 0.60 0.47-0.75 70 Co 0.31 <0.2-0.60 0.16 0.14-0.19 0.60 0.30-1.30 10 As 2.8 1.8-4.7 1.0 ■'T 1Г"> d 1.8 1.2-3.2 50 Mo 0.20 0.16-0.23 0.62 0.43-0.82 0.43 0.38-0.49 1 V 1.36 0.98-1.65 1.21 0.85-1.71 2.35 1.95-2.59 1 Se 0.50 <0.5-0.55 0.84 <0.5-1.16 0.81 <0.5-1.17 2 Dash (-) denotes the values below the detection limit; here and in Tables 2-4, X is the average value; Min is the minimum value; Max is the maximum value. Table 2 Concentration of toxic organic substances and their MPC values (;ig/l) in water of Volga River Toxic organic substances Upper Volga Middle Volga Lower Volga MPC X Min-Max X Min-Max X Min-Max Hydrocarbons of oil products Alkanes 12.0 1.45-19.3 31.4 6.2-114 10.0 0.9-17.7 Alkenes 0.1 0-0.4 1.6 0.7-4.0 0.5 CO 1CN О Total 12.1 1.45-19.7 33.0 6.2-118 10.5 0.9-19.5 50 Monatomic saturated alcohols 0.8 0-2.0 1.3 0-5.1 1.1 0.1-4.6 500 Ethers of carboxylic acids Dioctyl cebacate 3.9 0-11.6 0 0 0 0 1 Carbocyclic compounds Cyclohexane and its derivatives 0 0 0 0 0.1 0-0.8 10 Cyclopentadiene and its derivatives 0 0 0 0 0.4 0-1.0 10 Aromatic compounds Xylene 0.3 0-1.0 1.3 0-2.5 0.5 0.2-1.3 50 Isopropyl benzene 0 0 0 0 0.1 0-02 100 Orthophthalic acids ethers Dibutyl phthalate 2.8 1.3-4.5 25.2 5.7-55.7 32.1 9.6-44.5 1 Dioctyl phthalate 11 4.0-17.7 18.6 0-47.2 1.1 0.5-2.3 10 Heterocyclic compounds Derivatives of 1,3-dioxane 0 0 27.6 2.0-81.7 0 0 10 Sum of chlororganic pesticides (DDT, DDE, 0 0 0.01 0-0.04 0 0 0.01 a-hexachloran, y-hexachloran) contamination with alkyl derivatives of dioxane was revealed in the Gorkii Reservoir. Owing to large-scale application of polymer products, phthalates (used as plasticizing agents), and xylene (used for phthalic acid production) were observed in all the investigated sections of the Volga River (especially in the Gorkii Reservoir and the delta downstream of Astrakhan). Dibutyl phthalate, whose concentration in the water varied from 1.3 to 55.7 j.ig/1 (its MPC for fisheries is only 1 j.ig/1 ), deserves special attention. The MPC for oil products was not exceeded in the investigated sections of the Volga River except near the dam of the Gorkii Reservoir, which is probably affected by effluents from petro­ chemical enterprises located upstream of the Gorkii Reservoir near Yaroslavl city. Dangerous substances such as chlororganic compounds were not found in the investigated sites, which could be explained by their absence from the water or by their low concentrations (not exceeding the “ sensitivity threshold” of the applied method). Analysis of scientific papers and data collected by the Hydro­ meteorological Service of Russia has shown that, in individual samples of Volga water, the concentrations of certain dangerous substances (such as DDT, DDE, alpha-, and gamma-hexachloran) exceed the MPC. In 2002, these substances were also found in the Kuibyshev Reservoir (State Report, 2003).