Accumulation of mutagenic xenobiotics in water ecosystems with special reference to lake baikal

摘要

Mutagenic substances are amongst the msot dangerous compounds of the antropogenic pollution, their action may be delayed and that mmanifested in the subsequent generationsof animals (including fish) and people. recent sharp increasesin the number of tumours in fish in most cases can be attributed to the pollution of aquatic ecosystems with mutagenic and carcinogenic xenobiotics (MCX), with a smaller number of malformations caused by viral diseases. Chemical methods of detection are not sensitive enough to monitor MCX which can cause biological effects at extremely low concentrations in tissues of animals. The advantagesof biological testing are high sensitivity and possibility to identify compounds which acquire mutagenic and carcinogenic properties after metabolic activation, for instance with cytochrome P-450. We assayed tissue extracts of aquatic organisms (aquatic plants, decapoda, molluscs, fish, Baikal seals, fish-eating birds and their eggs) from Lake Baikal and the Selenga River estuary as well as fresh and waste water samples using Salmonella/microsome Ames test. Presence of MCX was followed in the main food chain in Lake Baikal which consists of a primary zooplankton producer Epishura baikalensis (90