Nonylphenol exposure in Labeo rohita (Ham.): Evaluation of behavioural response, histological, haematological and enzymatic alterations.

The impact of acute and chronic exposure of nonylphenol (NP) on behaviour, histopathology, haematology and biochemical parameters of Labeo rohita (Hamilton, 1822) was investigated in the current study. The 96 h LC50 of NP for L. rohita was estimated to be 0.548 mg L-1. Acute toxicity of NP induced several behavioural alternations. Further, sub-lethal NP exposure for a period of sixty days to 1/10th (0.0548 mg L-1), 1/15th (0.0365 mg L-1) and 1/20th (0.0274 mg L-1) of 96 h LC50 resulted a reduction in total erythrocyte count and haemoglobin content whereas the total leukocyte count was observed to increase significantly. Among the biochemical parameters, blood glucose level increased, but there was significant decrease in total serum protein, albumin and globulin level. Significant alterations occurred in the histological architecture of gill tissue in NP exposed groups. The catalase and superoxide dismutase activity in gill tissues were elevated significantly while the concentration dependent inhibition of acetylcholinesterase activity was observed on 20th, 40th and 60th day of NP exposure. An increased glutathione-S-transferase activity in gill tissue was also observed in NP exposed groups. The present ecotoxicological study provides a reliable indication for the obligation to control the use and safe disposal of NP.