8. Biomagnification occurs in food chains because some dangerous chemical substances are not easily removed from living tissues. When a contaminated plant is eaten, it passes the contamination on to the herbivore. When an herbivore eats many contaminated plants, the toxin builds up in their tissues. When a carnivore in turn eats many contaminated herbivores, the toxin builds up to concentrations that are even higher than those in the herbivore. The story continues as we move higher on the food chain, so that the top consumer has the highest concentration of the toxic substance. High concentrations of this dangerous chemical often lead to mutations, cancers, and often to early death.
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