Accumulation of Benzo[a]pyrene in a Larval Bivalve via Trophic Transfer

The diatom Thalassiosira pseudonana was cultured in 10 μg/L 14C-benzo[a]pyrene (B[a]P) and subsequently fed to larvae of the hard clam Mercenaria mercenaria. The rate of direct uptake of B[a]P from seawater by the diatoms was much greater than the rate of trophic transfer of B[a]P from the diatoms to the clam larvae. This was attributed to greater efficiency of direct uptake and to the larger quantity of B[a]P available in the water. A comparison of direct uptake by bivalves (as reported in the literature) with trophic transfer measured in the present investigation indicated that the processes may be equally important in accumulation of B[a]P in natural populations of bivalves.