| Popis: |
This chapter focuses on the characteristics and processes that influence the availability of chemicals at the environment-organism interface in multiphase systems, such as sediment, and the rate and magnitude of absorption of available chemical into the organism. However, experimental results are sometimes equivocal, reflecting technical and analytical difficulties, as well as the complex interaction of animal behavior and physiology, contaminant physicochemical properties, and sediment-water characteristics and chemistry that determines both bioavailability and organism uptake and accumulation. Benthic invertebrates are probably the most diverse and difficult group to model because of their wide variety of feeding behaviors and activity patterns. Accumulation in benthic organisms becomes increasingly important as contaminants are transported downward by sedimentation processes. The kinetics of uptake from water has been well characterized in a variety of marine and freshwater fish, and several models are available to calculate bioaccumulation of, primarily, organic chemicals. |
