CONTAMINANTS IN OYSTERS IN KANEOHE-BAY, HAWAII

Despite past and present concerns about the toxicity and persistence o f various environmental contaminants (heavy metals and pesticides), re latively few studies have documented their concentrations in tropical or sub-tropical marine ecosystems. In this investigation, a 'mussel wa tch' approach was applied in Kaneohe Bay, Hawaii, to assess the presen t levels of potential contaminants in the Pacific oyster, Crassostrea gigas. Geographical gradients of these contaminants were observed and related to what is known about past and present inputs, Concentrations of lead, copper, chromium and zinc were elevated in oyster tissues ne ar stream mouths in the southern watersheds of Kaneohe Bay. Dieldrin a nd chlordane concentrations in oysters from one of these sites exceede d the US Environmental Protection Agency's screening levels to protect human health, and were much higher than in oysters from the east and Gulf coasts of the temperate mainland USA.