ABSTRACT
This chapter addresses the uptake and bioaccumulation of organic chemicals from the water and sediments into single organisms and in entire food chains. It summarizes the state of knowledge regarding the mechanism of chemical uptake and bioaccumulation in various aquatic organisms and presents a model to predict the accumulation of organic substances in aquatic food chains. The chapter shows how the model can be used to assess toxic effects in fish and other aquatic organisms. The rate of fish growth can have a significant effect on the steady-state concentration in the fish. The bioavailability of organic chemicals in natural waters is largely determined by the interaction of the chemical with organic carbon-containing materials, which occur both in particulate and in dissolved form. Toxic effects resulting from chemical exposure can be expected to occur when the concentration of the chemical in the organism reaches a certain threshold level.
