private yachts and motorboats were the prime users of tributyl tin (TBT)-based antifouling paints that have had well-documented profound reproductive and developmental effects on molluscs such as oysters and whelks from the 1970s and 1980s (first surfacing as a serious problem in French oyster growing areas; Alzieu et al., 1986) before such paints were withdrawn from use. Marinas, where large numbers of recreational vessels are moored, tend to be hotspots of pollution by hydrocarbons, sewage and antifouling compounds.