PATHWAYS OF SILVER UPTAKE AND ACCUMULATION BY THE AMERICAN OYSTER (CRASSOSTREA-VIRGINICA) IN CHESAPEAKE BAY

Metabolic pathways of silver (Ag) accumulation were examined by exposing hatchery-reared oysters to Ag in a variety of forms including dissolved in water, associated with phytoplankton, and sorbed to sediments. Silver dissolved in water (2 and 5 μg l-1) was rapidly accumulated, with oysters reaching soft-tissue concentrations of 4 to 6 μg g-1 (several times that of controls) in 3-4 weeks. Uptake was negligible from suspended sediments as oysters rejected the particles as pseudofeces. Uptake of Ag associated with algal cells was negligible also: virtually all of this Ag passed through the oysters and was eliminated in the feces. Thus, the major pathway of accumulation in these studies was from dissolved Ag. © 1990.