Environmental impact of TBT: the French experience.

The deleterious effects of TBT released by antifouling paints were first documented in Arcachon Bay (France) at the end of the 1970s. As a result of the high level of water contamination, the production of Pacific oysters was severely affected by a complete lack of reproduction and the appearance of calcification anomalies which were responsible for a strong decline in the marketable value of the remaining stock. Regulations that had been successively adopted from January 1982 had positive effects on the recovery of the oyster grounds by reducing ambient water concentrations. Most antifouling paints act by releasing toxicants into the water which avoid the fixation of the organisms responsible for fouling. The use of these paints results in significant inputs of biocides in the waters. The harmful effects on non-target organisms were first evidenced in the bay of Arcachon (France) where the most acute disturbances were recorded following tributyltin (TBT) contamination.