Biomagnification is a well-documented phenomenon where persistent hydrophobic organic contaminant concentrations in an animal become elevated over and above its food. This increase in contaminant concentration propagates through successive trophic steps in a food web.
Later definitions of biomagnification and food web biomagnification have imposed thermodynamic criteria specifying that biomagnification reflects a nonequilibrium process in which the chemical potential in an animal is elevated above that of its diet and environment. The GI magnification model and the new amendments to this framework explain how exposures through the diet can raise the chemical potential of the animal above that of its food and environment. The above mechanisms apply specifically to hydrophobic organic contaminants. However, other contaminants such as mercury are assimilated and distributed through tissues by different processes. Thus, while mercury conforms to the classic definition of biomagnification and food web biomagnification it is difficult to evaluate the behavior of this compound in the context of the thermodynamic definition of biomagnifica-tion. Further understanding of uptake, assimilation, and elimination mechanisms and the free energy relationships associated with these processes are needed to provide a unifying theory of biomagnification across other contaminant types.
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Global warming is a huge problem which will significantly affect every country in the world. Many people all over the world are trying to do whatever they can to help combat the effects of global warming. One of the ways that people can fight global warming is to reduce their dependence on non-renewable energy sources like oil and petroleum based products.