Endocrine disruptors: from Wingspread to environmental developmental biology

The production and release of synthetic chemicals into the environment has been a hallmark of the "Second Industrial Revolution" and the "Green Revolution." Soon after the inception of these chemicals, anecdotal evidence began to emerge linking environmental contamination of rivers and lakes with a variety of developmental and reproductive abnormalities in wildlife species. The accumulation of evidence suggesting that these synthetic chemicals were detrimental to wildlife, and potentially humans, as a result of their hormonal activity, led to the proposal of the endocrine disruptor hypothesis at the 1991 Wingspread Conference. Since that time, experimental and epidemiological data have shown that exposure of the developing fetus or neonate to environmentally-relevant concentrations of certain synthetic chemicals causes morphological, biochemical, physiological and behavioral anomalies in both vertebrate and invertebrate species. The ubiquitous use, and subsequent human exposure, of one particular chemical, the estrogen mimic bisphenol A (BPA), is the subject of this present review. We have highlighted this chemical since it provides an arresting model of how chemical exposure impacts developmental processes involved in the morphogenesis of tissues and organs, including those of the male and female reproductive systems, the mammary glands and the brain.