A review on ecotoxic potential of pollutants in fish

Abstract

Fishes in the aquatic food web are at the top of most aquatic food chains and form an important link in the aquatic-terrestrial food chain also. They are easily available in the wild, market, can be easily maintained in the laboratory and act as important models for indicating the outcome of exposure of human populations to toxic and genotoxic chemicals in drinking water. They respond to toxicants in a manner similar to higher vertebrates and metabolize and accumulate pollutants. Food is a major route for exposure of human populations to toxic chemicals in water so fish and shell fish have been recognized as major vectors for transfer of contaminants to humans, as these major sources of protein in many countries, are often contaminated with high concentrations of pollutants. In living systems, these are biotransformed to various toxic derivatives which react with DNA and lead to tumour development are carcinogenic and/or mutagenic to life leading to the number of cancer cases. Epidemiological studies have revealed that workers in the dye industry had a higher incidence of urinary bladder tumours than that of the general population. Therefore, in the present review an attempt has been made to document the work done in past on the use of fishes for studying toxicological changes induced by pollutants. Actually, toxicity and genotoxicity of dyes in fish has not been much explored, therefore along with the few reports available on dyes, literature on toxicity and genotoxicity of other aquatic pollutants has also been reviewed in the present study.