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.

T.I. Moiseenko et al. / Ecotoxicology and Environmental Safety 71 (2008) 837-850 845 Table 4 Characteristics of the physiological state of fishes caught in the Volga River Parameter, element Upper Volga Middle Volga Lower Volga X Min-Max X Min-Max X Min-Max Z 1.54 1.33-1.71 1.97 1.71-2.11 1.45 1.00-1.74 Percentage of the fishes demonstrating second and third stages of the disease 44.3 37.7-52.4 72.9 53.6-85.2 41.8 20.0-64.1 Percentage of the fishes demonstrating pathological disturbances in the liver 56.5 41.0-64.3 68.4 46.4-92.6 29.5 18.2-44.4 Percentage of the fishes demonstrating pathological disturbances in the kidneys 25.4 21.4-28.6 59.9 32.1-80.0 9.4 0-25.6 Hemoglobin (Hb) (mg/1) 103 81-124 96 52-126 88 56-122 Percentage of the fishes with Hb not exceeding 90 mg/1 15.2 0-37.5 22.0 11.8-40.0 54.3 9.1-80.0 Leucocytes Lymphocytes (%) 87.5 82-93 85.8 68-94 64.7 29-93 Monocytes (%) 1.0 0-2 1.5 0-5 3.7 0-10 Neutrophiles (%) 11.3 5-14 12.6 5-29 31.6 6-66 Including foamy (%) 7.7 2-11 6.0 1-20 16.2 3-34 Erythrocytes Mature forms (%) 94.1 89.9-96.6 94.1 85.5-99.9 92.6 76.1-99.8 Young cells (%) 5.9 3.4-10.1 5.9 0.1-14.5 7.4 0.2-23.9 Fig. 4. Pathological changes in the liver of bream (arrowed), x 320: a—normal structure; b—lipoid dystrophy; с—hydropic dystrophy; d—karyopycnosis and necrosis of hepatocytes; e—inflammation; and f—breakdown of blood cells. blood pressure, and blood flow deceleration. As a result, the supply of the tissues with blood becomes disturbed, and tissue hypoxia occurs. All these processes taking place together can lead to congestive edema. Disturbances revealed in the liver cell structure entail the development of first sclerosis, and then cirrhosis. 5.3. Kidneys The largest number of fish with pathological disturbances in the kidneys was caught in certain areas of the Gorkii and Kuibyshev reservoirs (Table 4). Pathological disturbances in the kidney tissue manifested themselves in fibrosis, where vast connective-tissue accretions substituted zones of necrosis in the canaliculi and interstitial tissue. In medicine, similar histopathol- ogy is typical of interstitial nephritis (fibroelastosis). In the connective tissue between the kidney canaliculi, pronounced interstitial inflammation (a diffuse infiltrate composed of blood cells) was observed (Fig. 5f). Signs of congestive hyperemia in the veins were revealed. Severe degeneration of adipose tissue was also diagnosed (Fig. 5d). In this case, the adipose tissue had a clearly formed structure; lipocytes were organized in groups ( “ lobules”, separated from each other by membranes with blood vessels). The following disturbances were found: destruction of lymphoid tissue (Fig. 5b); proliferative inflammation (Fig. 5c), with zones of necrosis surrounded by thick connective- tissue capsules, separating the disturbed zone from normally