DDT was widely used as a pesticide for 20 years. Its use was banned after studies showed severe side effects were evident in humans, the environment, and animals as a result of DDT. Which reason best explains why the side effects of DDT were so harmful?

DDT is persistent and can build up in the tissues of organisms over time. This bioaccumulation means that animals, including humans, can be exposed to increasingly harmful concentrations, especially higher up the food chain. Therefore, the best choice is “DDT bioaccumulates.”

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