Assessing pollution in coastal ecosystems: a preliminary survey using the micronucleus test in the mussel Mytilus edulis.

Mussels Mytilus edulis were sampled at increasing distances from urban effluents in two very different locations, Gijon (northern Spain, Europe, 43 degrees N) and Puerto Madryn (Argentina, South America, 43 degrees S), and from an industry effluent in Puerto Madryn. The micronucleus test was performed on branchial cells. For the three situations, a statistically significant negative association was found between the distance of sampling site from the effluent and the mean number of micronuclei per 1000 cell counts, in a range of distances as short as 300m. The micronucleus test in Mytilidae, here revealed to be sensitive enough to monitor urban pollution, is proposed for routine surveys of pollution as a bioindicator of choice for coastal ecosystems.