Tributyltin contamination in the Firth of Forth (1975–1987)

Contamination of the Firth of Forth (Scotland) by tributylin compounds leached from antifouling paints has been identified using the degree of penis development (imposex) in the common dogwhelk Nucella lapillus. In 1987, a high degree of imposex was observed in the vicinity of pleasure craft activity, fishing harbours and a boat yard, reflecting localised inputs of tributyltin from these sources. Dogwhelks collected in 1975 from sites comparable to those surveyed in 1987 showed lower degrees of imposex and also a lower incidence of penis development in females.