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is when toxins build up in a food chain. The animals at the of the food chain are affected most severely.
This is what happens:
1.Small amounts of toxic substances - often from activity - are taken up by plants.
2.These plants are eaten by consumers.
3.The primary consumers are eaten by consumers, and the secondary consumers are by higher level consumers.
4.At each stage () of the food chain, harmless substances are excreted but the toxins remain in the tissues of the organisms - so the of toxin becomes most concentrated in the body tissues of the animals at the of the food chain.
An example of bioaccumulation is the use of DDT as an in the 1950s and 1960s. Birds of prey were badly affected because it made the shells of their eggs very , causing them to break easily when the birds tried to incubate them.