'Endocrine disruption' and the 'wildlife connection'

A 'wildlife connection' has been proposed to link several human sexual-endocrine abnormalities with synthetic chemicals in the environment. A review of several frequently cited examples of 'endocrine disruption' in wildlife indicates, however, that any connection is remote at best. The reported loss of sexuality by bald eagles is attributed to misinterpretations of the wording in a popular article; no supporting data can be found. The existence of feminized male western gulls remains hypothetical; an alternative and plausible explanation for a skewed sex ratio and female-female pairing in this species is supported by field data. Dioxin-related effects in wildlife complement an extensive human data base but provide no obvious insight to the causes of the sexual-endocrine dysfunctions. Sexual abnormalities of the Lake Apopka alligators are attributed to leakage of the nematicide DBCP from a manufacturing facility; DBCP is no longer used because of its capacity to reduce human sperm counts to zero. While concern about effects of low-level exposure of people to synthetic chemicals that exert biological activity continues to he justified, human health risk assessment protocols might incorporate both an extra amount of skepticism and an enhanced respect for scientific rigor.