biomagnification(redirected from biologic magnification)
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The increasing concentration of a substance, such as a toxic chemical, in the tissues of organisms at successively higher levels in a food chain.
biomagnificationThe result of bioaccumulation and biotransfer by which tissue concentrations of chemicals in organisms at one trophic level exceed tissue concentrations in organisms at the next lower trophic level in a food chain.
biomagnification(bī″ō-mag″nĭ-fĭ-kā′shŏn) [ bio- + magnification]
The increase in the concentration of biologically active substances in organisms as they rise up the food chain. Pesticides are one example of a substance that biomagnifies. Trace concentrations of agricultural pesticides may be ingested by aquatic organisms, such as plankton. Plankton may be consumed by filter-feeding clams or small fish, which will store larger concentrations of toxins in fat or muscle. These animals may be eaten by predators such as trout or salmon, which may subsequently be consumed by carnivores such as bear, eagles, osprey, or humans. In each successive level of the food chain, higher and higher concentrations of pesticides will be found. Ultimately enough pesticide may be present in individual organisms to cause disease.