Effects of Organotin Antifouling Paint Leachates on Pearl Harbor Organisms: A Site Specific Flowthrough Bioassay

Tributyltin (TBT) concentrations in the range of 0.04 to g/l were used for treatments on marine communities at Pearl Harbor, Hawaii. Over an exposure phase of three months and a recovery phase of two months, significant effects were noted on many species of fouling organisms. Four of the six most abundant fouling taxa sustained 100% mortality at g/l TBT. Overall species abundances of fouling organisms were reduced by 50, 60 and 80% by TBT treatments of 0.5, 1.8 and g/l, respectively. TBT concentrations of g/l and higher caused significant reductions in numbers of species and species diversity of organisms that settled on virgin panel surfaces. Significant mortality of oysters (Crassostrea virginica) was observed only in g/l treatments. However, condition indices showed that general health of oysters is markedly reduced by TBT concentrations of g/l and higher.