Hepatotoxic potential of Malathion in the freshwater teleost, Cirrhinus mrigala (Hamilton)

Abstract

Freshwater edible fish, Cirrhinus mrigala, were exposed to a sublethal concentration (3 microl/L) of commercial grade malathion (50% EC) for 5, 15, or 25 days. After each exposure period, the liver was removed to study biochemical alterations. An increase in free amino acids, protease activity, and acetylcholine (Ach) levels, in contrast to decrement in total, structural, and soluble proteins, and acetylcholine esterase (AchE) activity were observed at 5 and 15 days of exposure, but on day 25 of exposure, all values reached near normalcy. The restoration to normalcy implies that after 15 d of exposure, an oscillatory phase in protein turnover toward a more-synthetic phase seems to occur, leading to the establishment of recuperation and adaptation phenomena.