Tributyltin and mussel growth in San Diego bay

During three San Diego Bay field tests (1987- 1988), juvenile mussels (Mytilus edulis) were exposed to mean ambient tributyltin (TBT) concentrations from 7 to 500 ng/l for 12 weeks. Mussel lengths and weights, seawater [TBT] and various physical/chemical parameters were measured weekly. TBT bioaccumulation was measured at the end of each test. At mean seawater [TBT] 2200 ng/l significant reductions in mussel growth rates were observed. Other environmental factors appear to modify the effects of TBT on juvenile mussel growth below 100 ng/l TBT. No clear relationship between growth rate and [TBT) in mussel tissues at concentrations below 1.5 ug TBT/g tissue was found. Although there appears to be a linear relationship between TBT bioaccumulation and seawater [TBT], the relationship between bioconcentration factor and seawater [TBT] appears to be inverse and exponential. No dose-related mortality was observed.