In the 1960s and 1970s, commercial vessels commonly used bottom paints containing tributyltin (TBT), which has been banned in the International Convention on the Control of Harmful Anti-fouling Systems on Ships of the International Maritime Organization due to its serious toxic effects on marine life (such as the collapse of a French shellfish fishery).
The imposex stages of female dog whelks and other molluscs (including Nucella lima) are used in the United Kingdom and worldwide to monitor levels of tributyltin.