Acute toxicity of vegetable oil factory effluent to some freshwater teleosts in relation to size.

Specimens of Cirrhina mrigala (Ham.), Labeo rohita (Ham.) and Channa punctatus (Bl.) falling in the size (total length) range of 5.5 +/- 1.0 cm to 27.0 +/- 2.0 cm were exposed to different concentrations of the vegetable oil factory effluent for evaluating the influence of size on the acute toxicity of the factory effluent. The results suggest that relative toxicity of the effluent decreased with increase in the size of the fish. However, for specimens exceeding 20.0 +/- 1.6 cm in size, the toxicity of the effluent increased with an increase in size of the fish. The results also indicate that C. mrigala was most susceptible, while C. punctatus was least susceptible to the effluent.