Assessment of fish health status in the Pechora River: effects of contamination.

The present study aimed to assess the ecological situation in the Pechora River Basin (east part of Sub-Arctic Russia) using histopathologies of fish and to relate fish health to environmental quality. This paper reports histopathological alterations of fish kidney, liver, and gills and their association with chemical contamination of the Pechora River. A variety of histopathological changes was found. Differences between studied species and sites of the Pechora River with regard to the type, prevalence, and severity of lesions were studied. The types of the lesions indicated that fish respond to both direct toxicant effects of contaminated water and sediment, and secondary stress effects caused by factors such as parasitism. The structural modifications found in this study are a result of acute damage associated with short-term exposure as much as chronic response due to long-term pollution.