§ Mr. OnslowTo ask the Secretary of State for the Environment what rivers in England and Wales are known to have been polluted by the use of tributyl tin by boat owners.
§ Mr. Howard[holding answer 26 May 1989]: The main freshwater rivers affected have been those carrying large numbers of pleasure craft, which were treated with tributyl tin antifouling paints before the Government banned their sale and supply in 1987. We have direct evidence of contamination of the Rivers Bure, Yare, Great Ouse, Thames, Aire and Medway. It is too soon to detect the effect of the ban in reducing tributyl tin concentrations in rivers.