Acetylthiocholine (ATC) - Cleaving cholinesterase (ChE) activity as a potential biomarker of pesticide exposure in the Manila clam, Ruditapes philippinarum, of Korea

► We determined ChE activity of Manila clam to be a suitable biomarker for OPs. ► Clear dose-response relationship was shown between ChE activity of clam and OPs. ► Clams from the mid-western coast of Korea indicated spatial variation in ChE activity. ► IBP concentration showed a significant relationship with ChE activity in Manila clam. ► ChE activity of clam can be useful biomarker of OPs in the coastal environment.