Abstract

The aim of the study was to investigate the effects of organophosphorous pesticide on thecholinesterase activity of different organs of Mytilus edulis. The mussels were exposed to serial dilutions of the pesticides (0, 50, 100, 200, 500, and 1000 µg/l) for 96 h. A significant inhibition of the cholinesterase activity from gill occurred at the lowest concentration, which indicated that gill was the most sensitive organ. The moderate sensitive organs were foot and mantle, which wereinhibited by trichlorfon at 200 μg/l. The least sensitive organs were hemolymph, posterior adductor muscle and digestive gland were inhibited at 1000 μg/l. After incubation of the trichlorfon-exposed mussels for seven days in clean media, the cholinesterase activities from different organs of mussels were not cured completely. The cholinesterase activities from hemolymph, gill, posterior adductor muscle and digestive gland recovered, while the persistent inhibition of cholinesterase activity from foot and mantle were observed. 

Key words: Biomarker, cholinesterase, mussel, trichlorfon.