Why would Spotted Seatrout and Catfish show high levels of PCBs and Dioxins?
Once PCBs and dioxins have entered into an animal’s body they get stored in fat tissue. This makes it hard for the organism to eliminate them from its body. As you move up the food chain the PCBs/dioxins compounds begin adding up (biomagnification). While animals do eliminate them slowly from their bodies, their physiological systems may not be able to keep pace with the concentration in the environment. Thus some individuals begin accumulating concentrations that pose a risk to humans (or other predators). Predators that are at the top of the food web are going to accumulate the greatest concentrations. It is important to note that not all animals are the same at accumulating PCBs and dioxins. Factors such as growth rate, dietary preferences, migration habits, etc. play a role in determining the concentration that accumulates in the body.
