A method for studying the impact of polluted marine sediments on intertidal colonising organisms; tests with diesel-based drilling mud and tributyltin antifouling paint

This paper describes a novel sediment bioassay which can be used in intertidal mud or sand, thereby exposing a contaminated sediment to a large range of naturally colonising fauna. Natural sediment, in which invertebrates had been killed by freezing, was mixed with diesel-based drilling mud (nominally 1000 mg kg^–1 dry wt as diesel-based-mud equivalents) or particulate tributyltin (TBT) copolymer antifouling paint (nominally 0.1, 1.0 and 10 mg TBT kg^–1 dry wt). The contaminated sediments were then re-laid intertidally in trenches lined with polythene mesh.All treatments except 0.1 mg TBT kg^–1 impaired the casting activity of the polychaete, Arenicola marina. Populations of the polychaete, Scoloplos armiger, and the amphipod, Urothoe poseidonis, were reduced in all contaminated treatments, and a dose-response effect of TBT was demonstrated. No clear effects on other groups (e.g. molluscs) were seen.The results showed that this is a useful technique, although further development is required before it can be used routinely.