Tributyltin environmental studies in Chesapeake Bay

Abstract

This paper presents and discusses all available data on tributyltin (TBT) monitoring and toxicity studies conducted in Chesapeake Bay. TBT evaluations in the water column were more numerous than microlayer, sediment or tissue assessments. Maximum TBT concentrations occurred in marina or harbour areas during the beginning of the boating season; significant reductions were reported during the summer and early fall. Significantly lower TBT concentrations generally occurred in non-marina areas. TBT toxicity data were available for various Chesapeake Bay invertebrates and fish. Few studies have been conducted with phytoplankton. Chesapeake Bay copepods were the most sensitive organism tested. Bivalve embryos were also sensitive to TBT. A comparison of TBT environmental concentrations with toxicity data was attempted. Maximum TBT concentrations reported in the water column of Chesapeake Bay marinas would likely be toxic to some copepods and early life stages of bivalves. Mean TBT values reported in some marinas would also be toxic to sensitive Chesapeake Bay copepods. If laboratory toxicity data are considered a realistic indicator of real world effects, then most of the Chesapeake Bay organisms tested to date would not be affected by TBT concentrations reported in non-marina areas. Full life-cycle toxicity tests are needed to evaluate chronic effects of environmentally realistic concentrations of TBT to Chesapeake Bay biota.