DETERMINATION OF 96-HOUR LC₅₀ VALUE OF ISOPROTURON FOR THE FRESHWATER FISH CYPRINUS CARPIO (L.)

Devika Rani H K and Parimala B

Abstract

The present study focuses on estimating the 96-hour LC₅₀ value of the herbicide Isoproturon in the freshwater fish Cyprinus carpio. Acute toxicity tests were conducted according to APHA standard procedures, and the LC₅₀ was determined using Probit analysis. Before experimentation, the fish were acclimated to laboratory conditions for 30 days. A stock solution of Isoproturon was prepared, and groups of fish were exposed to different concentrations of the herbicide for 96 hours. Findings indicated that the 96-hour LC₅₀ value for Cyprinus carpio was 1.56 mg/L. The sensitivity of the fish to Isoproturon increased with both higher concentrations and longer exposure times, with mortality rising proportionally to the herbicide concentration.