Endocrine Disrupters

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Having largely lost the intellectual debate on cancer (although their spurious claims still adversely affect policy), anti-chemical activists have decided to add more tools to their arsenal. Among their most powerful tools is the claim that chemicals are causing widespread problems by disrupting the endocrine systems of humans and wildlife. Accordingly, activists argue that we should ban or heavily regulate various chemicals, particularly pesticide products, on the basis of assertions that such chemicals may have an endocrine-related effect. 

Endocrine systems in both humans and animals consist of a series of glands that secrete hormones and send messages throughout the body. Working in conjunction with the nervous system, these messages trigger various responses, such as growth, maturation of reproductive systems, and contractions during pregnancy. Foreign chemicals can disrupt proper functioning of the endocrine system and lead to health problems. Environmentalists refer to such external chemicals as endocrine disrupters, but others use more neutral terms because not all effects are negative or substantial. The American Council on Science and Health (ACSH) calls them endocrine modulators, which is the term used in the subsequent discussion. The National Research Council calls them “hormonally active agents.” 

The endocrine disrupter alarm tactic focuses primarily on synthetic chemicals. Allegedly, because we have used and continue to use man-made chemicals—particularly a class of chemicals called organochlorines, such as DDT (dichloro-diphenyl-trichloroethane) and PCBs (polychlorinated biphenyls)—the public and wildlife are widely suffering with everything from infertility and cancer to neurological disorders and developmental problems. But before rushing to ban and regulate all man-made chemicals, policymakers should review some facts.