A STEADY-STATE MODEL OF PCB ACCUMULATION IN DAB FOOD-WEB

A five-compartment steady-state food web model is proposed for the ben thic food web leading to the dab. Three exposure pathways are consider ed in the description of accumulation by benthic animals: ingestion of particulate contaminants associated with either sediment or phytoplan kton, and respiratory uptake of free dissolved contaminant in overlayi ng water. Application of the model to a simple food web in the Bay of Seine (Eastern Channel) indicates that : a) feeding is the principal r oute of contamination, especially for PCB which have more than four ch lorine atoms in the molecule ; b) excretion and growth rates, phytopla nkton lipid fraction and organic carbon content of sediment are the pa rameters which mostly determine the chemical bioaccumulation in the fo od web.