Adverse effects of some selected agrochemicals and pharmaceuticals in aquatic environment with reference to amphibians and fish

ABSTRACT

The agrochemicals and pharmaceutical effluents released into the aquatic environment without toxicological risk have the abilities to disrupt the function of endocrine systems. A number of aquatic species are being exposed to small amount of everything from Prozac to perfume to birth control pills that make their way into rivers and streams. Some antidepressants drugs cause development problems in fish, and metamorphosis delays in frogs. The health of amphibians can suffer from exposure to pesticides because of their semi permeable skin, the development of their eggs and larvae in water, and their position in the food web, amphibians can be exposed to waterborne and airborne pollutants in their breeding and foraging habitats. Some studies have shown that several frogs, toads and other amphibian species, especially at their more vulnerable larval stages, can be highly susceptible to fairly low levels of nitrate and nitrite exposure. When exposed to moderate amounts of nitrates and nitrites, some tadpoles and young frogs reduced their feeding activity, swam less vigorously, developed physical abnormalities, suffered paralysis and eventually died. Several agrochemicals reduced the cholinesterase activity of frogs. Some results reported that the trout absorb waterborne pyrene through the branchial and dermal routes