TRIBUTYLTIN (TBT) POLLUTION IN THE COASTAL WATERS OF WEST BRITTANY ASINDICATED BY IMPOSEX IN NUCELLA-LAPILLUS

Tributyltin (TBT) pollution in west Brittany coastal waters was assess ed in 1992, 1993 and 1994 using the bioindicator of imposer (superimpo sition of male sexual characters on females) in the neogastropod Nucel la lapillus, Imposer was detected at all 75 stations sampled, fi om Ke rfissien on the north coast to lie de Sein in the south-west, indicati ng widespread pollution even at sites having full exposure to the Atla ntic. Imposer levels in the Bay of Brest were found to be high, female sterilization was prevalent and certain populations appeared to have been exterminated, notably in the northern part of the Bay, The eviden ce suggests that the 1982 legislation, banning the use of TBT-based an tifouling-paints on vessels less than 25 m, is being ignored in certai n areas; some small ports, like those of the islands, are contaminated despite the fact there are few vessels eligible to use this paint.