Uptake of PCBs from sediment by Nereis virens and Crangon septemspinosa.

The concentration of PCB, as Aroclor 1254, accumulated from sandy sediment by Nereis virens is directly related to PCB concentration in sediment and to exposure time, and is inversely related to worm size. There was no indication of equilibrium concentrations being attained during 32 days' exposure. Concentration factors at 32 days ranged from 10.8 for 0.6-g worms to 3.8 for 4.7-g worms. There was no obvious excretion of PCB by N. virens during 26 days' post exposure. Accumulation of PCB by Crangon septemspinosa is directly related to PCB concentration in sediment and inversely related to animal size. Concentration factors at 32 days ranged from 3.5 for 0.1-g shrimp to 1.9 for 2.9-g shrimp. Field collected N. virens ranging in weight from 1.3 to 20.0 g were analyzed for PCB, sigma DDT and dieldrin. Smaller worms had accumulated more per unit weight of each compound than larger worms.