Impact of glyphosate on biochemical constituents of the freshwater fish, Catla catla

The freshwater fish, Catla catla was exposed to the test toxicant glycil (SL 41%) (glyphosate), an organophosphate herbicide under static and continuous flow-through systems to determine the acute toxicity values for 24, 48, 72 and 96 h. The LC 50 values obtained in static method were 6.622, 6.546, 6.05 and 5.798 mg/L respectively for 24, 48, 72 and 96 h and in continuous flow-through system the LC 50 values were 5.759, 5.374, 5.249 and 5.191 mg/L respectively for 24, 48, 72 and 96 h. After determination of LC 50 values the fish were exposed to both lethal and sub-lethal concentrations of glyphosate to study the changes in biochemical constituents (glycogen and protein content) of the vital organs viz.; gill, brain, liver, kidney and muscle of the fish Catla catla. The 24, 48, 72 and 96 h LC 50 value of glyphosate were found to be decreased in static and in continuous flow through system indicating a decrease with time of exposure and also the static LC 50 values were found to be higher, compared to the continuous flow-through values. Depletion of total glycogen and protein contents were observed in all the tissues of the fish exposed to toxicant. The results obtained were discussed with the available literature.