BIOAVAILABILITY AND BIOACCUMULATION OF PAH IN AMPHIPODS EXPOSED TO REFERENCE AND HARBOR SEDIMENTS

Abstract

The amphipods Corophium volutator collected from inter-tidal mud flats away from urbanization display the presence of phenanthrene, while larger molecular weight PAHs were only detected in sediments. The latter compounds were abundant in sieved surface sediments collected from Halifax Harbor receiving combined road runoff and sewage effluents and a smaller fraction of the contaminants were bioavailable to amphipods. In laboratory exposures, the kinetics of contaminants uptake by amphipods displayed the steepest increase in concentration the first day of exposure, continued to increase and then decreased, reaching a steady state within a week. The depuration of PAH was more than ten times slower than observed for maximum uptake. Our study indicated the important role played by feeding in the bioavailability and toxicity of sediments. The PAH fingerprint associated with the grain size of particles needs pursuing to better delineate the exposure pathway of PAH to sediment dwelling organisms.

Keywords:

• Amphipods
• feeding
• bioavailability
• sediments
• harbor

Funding for this research was from the Department of Fisheries and Oceans and the National Science and Engineering Research Council of Canada. We would also like to acknowledge the Coop Program at Dalhousie University.