Chlorpyrifos (CPF) and carbendazim (CBZ) are widely used pesticide and fungicide in India. The 96 h LC(50) values of chlorpyrifos and carbendazim for the marine invertebrate Donax faba, were 247.72 μg L(-1) and 200.82 μg L(-1) respectively. CBZ was found to accumulate less than CPF. Gill, body and