Haematological alterations in Cyprinus carpio as biomarkers of Cypermethrin toxicity

Possible effects of a synthetic pyrethroid pesticide Cypermethrin (25%EC) were observed in a freshwater fish Cyprinus carpio (Linn.) Juveniles of test fish were exposed for lethal (96h LC50 i.e. 3.31µg/l) and sublethal (1/10th of 96h LC50 i.e. 0.331µg/l for 5, 10 and 15 days) concentrations of cypermethrin to study the haematological parameters: Red Blood Cell (RBC) count; white blood cell (WBC) count; haemoglobin (Hb); Packed Cell Volume (PCV); Mean Corpuscular Volume (MCV); mean corpuscular haemoglobin (MCH); Mean Corpuscular Haemoglobin Concentration (MCHC). RBC count, Hb content and PCV showed decrement at both lethal and sublethal concentrations. WBC count and MCHC exhibited increasing trend at sublethal and decreasing trend at lethal concentration. Elevated values of MCV were recorded at both lethal and sublethal concentrations where as MCH exhibited an increasing trend in all exposure periods of lethal and sublethal concentrations. The haematological alterations led to the conclusion that the cypermethrin has toxic effects on freshwater fish Cyprinus carpio, and that its presence in an aquatic ecosystem may jeopardize the health of status of the ecosystem and biota therein.