Evaluation of the micronucleus test on Mytilus galloprovincialis for monitoring applications along French coasts

With a view to monitoring applications, the micronucleus (MN) test was evaluated on hemocytes from Mytilus galloprovincialis obtained in intermediate and contaminated sites along the French Mediterranean coast. A simple, rapid method of sampling and cytological preparation was tested. In vivo determinations of MN variation observed from February to May did not demonstrate clearly the exposure of organisms in highly polluted areas. To provide a basis for long-term interpretation, measurements of chemical pollutants in mussels, as performed by the National Observation Network, were compared with MN test results. The determination of an MN base level specific to each site, though not always related to the different chemical pollutants present, indicated that intersite comparison over wide areas of the French coast might prove difficult. Micronuclei, which have already shown their potential value as an index for the genotoxic effect of the marine environment, need to be improved before monitoring application.