Monitoring of Tributyl Tin Contamination in Six Marine Inlets using Biological Indicators

Abstract

Dogwhelk and periwinkle specimens were collected from six bays/estuaries in 2000, where Tributyl Tin (TBT) contamination was suspected. In four estuaries, shells of dead Pacific oysters were collected from 7 sites in the vicinity of culture installations. Observations on imposex in dogwhelks, intersex in periwinkles and shell thickness in the Pacific oysters were used to assess the degree of TBT contamination. The results showed low levels of contamination, which are unlikely to have detrimental effects to mollusc culture or fisheries in Mulroy Bay, Valentia Harbour or Tralee Bay. Thickening of oyster shells was detected in Carlingford Lough, Waterford Harbour, Cork Harbour and Fountainstown. The small degree of thickening was considered unlikely to affect marketability.