Effect of synthetic detergents on some of the behavioral patterns of fish fingerlings (Cirrhina mrigala) and its relation to ecotoxicology.

With the wide spread use of synthetic detergents for household purpose, it is inevitable that these compounds would find their way into rivers and ponds. The effect of detergents on tissue of different fishes have been studied by Abel (1974) and Bromage et al. (1976). Gills, a primary site of osmoregulation, as well as respiration, may be highly vulnerable to lesions because they are in immediate contact with aquatic toxicants. The most prominent manifestation of the acute toxicological effect of detergents is on the gi~ tissue of the fish. Destruction of the gill epithelium is regarded as a consequence of the reduction of surface tension by the presence of surfactants (Bock 1965). Exposure of fish to elevated level of surfactants cause multiple hepatomas to develop on the gill tissue resulting in diminished oxygen uptake and impairment of electrolyte balance (Schmid and Mann 1961). Schooling patterns of fish have been reviewed by Partridge (1982). Detergent causes impairment of chemoreceptor organs (Bardach et al. 1965) and damage to epidermis and pharyngeal wall (Brown et al. 1968). Eleven species of fish exposed to a mixture of hard alkyl benzene sulphonate based detergent under varying environmental conditions and during different stages of development have shown wide differences in response (Thatcher 1966). Behavioural changes have been used successfully as rapid and sensitive indicators of toxic stress in fish (Sprague et al. 1965; Bengtsson 1974 and Besh et al. 1977).