§ Mr. Steenasked the Minister of Agriculture, Fisheries and Food what tests have been carried out by his Department of the effect on fish, and shellfish, including oysters, of tributyl tin in the rivers of Devon and Cornwall; and if he will make a statement on the implications for human consumption of such fish and shellfish.
§ Mr. MacGregorMy Burnham-on-Crouch Laboratory has carried out tests both in the laboratory and at selected sites around the coast. This work which has included some sampling in Devon and Cornwall, has been concentrated on pacific oysters. It has indicated that the presence of tributyl tin in water can cause shell thickening and reduced growth, thereby inhibiting the cultivation of pacific oysters in certain areas. The levels of tributyl tin detected in affected oyster flesh are extremely low and should pose no risk to human health.