A Study of Endosulfan Caused Lethal Effects as well as Histopathological Changes in Common Carp (Cyprinus carpio)

To evaluate the toxic effects of pesticide Endosulfan in fish, acute toxicity tests were carried out in valuing common carp (Cyprinus carpio) of 5-20 and 21-40 gr, using static water of 21°C and employing Organisation of Economic Coopration and Development (O.E.C.D) method .
Mortality limits of 0.0002-0.0022 and 0.001-0.0046 mg/lit were found in fish of 5-20 gr and 21-40 gr, respectively. The LC50 of 0.0061, 0.0029, 0.0016 and 0.0009 mg/lit were obtained in fish of 5-20 gr within 24, 48, 72 and 96 hours of post- challenge, respecti vely, while those in fish of 21-40 gr were 0.0079, 0.0053, 0.0035 and 0.0024 mg/lit, respectively.
The affected fish showed pale colour, irregular swimming behaviour, whirling and bottom sitting.
Following a temporary recovery, fish showed sufferings of severe convulsion and respiratory disorder, resulting in death within a short time after challenge.
Histologically, there were hyperemia and inflammation of secondary lamellae in the fish challenged with lower doses of the pesticide whereas a general necrosis was observed when fish were in contact with higher doses. Similar histopathological changes were observed in the kidney and liver tissues.
According to the mortality limits and LC5o (less than 0.1 mg/lit), this pesticide should be considered as a very highly toxic chemical for common carp, causing a rapid and accumulative mortality in fish.