Endocrine disruptors: update on xenoestrogens

Abstract

Endocrine disruptors and their possible impact on human and animal health have become a topic of discussion and an area of active research in toxicology. A focus has been on xenoestrogens, i.e., environmental chemicals with estrogenic activity. In principle, there is agreement that such compounds, in high doses, may cause developmental, reproductive and tumorigenic effects ("hazard"). A matter of controversy is the question of risks associated with xenoestrogens under realistic (low) exposure scenarios; this is due to uncertainty on how to assess the interactions of exogenous compounds with the endocrine system and its complex regulation. Our overview will address topics including: consequences from previous clinical use of the potent estrogen diethylstilbestrol with particular emphasis on dose-response relationships, other observations in humans exposed to estrogenic chemicals in an occupational context, and available information on exposure levels of synthetic and naturally occurring estrogens in the diet. Together with a critical appraisal of methods to detect and quantitate the estrogenic activity of synthetic and naturally occurring chemicals, novel aspects in the risk assessment for endocrine active compounds are discussed.

Epigenetic Reprogramming Induced by Environmental Estrogens

“…Based upon numerous previous studies, xenoestrogens, also called "environmental estrogens or hormones" or "Endocrine Disrupting Compounds (EDC)", are considered as serious environmental hazards that have hormone disruptive effects on human and wildlife health [5,6]. Studies have found that fetuses and young children exposed to BPA are at risk for secondary sexual developmental changes, brain and behavior changes and immune disorders [7].…”

Publications in toxicology: the current situation

“…The availability of funds in areas of political preference may have a higher impact on the choice of a particular research field than scientific considerations. A now classical example for such a development is the global wave of publications on ''endocrine disruptors'' (Degen and Bolt 2000).…”

Influence of Estrogen and Xenoestrogens on Basolateral Uptake of Tetraethylammonium by Opossum Kidney Cells in Culture

“…Xenoestrogens as environmental contaminants have sparked much debate as a public health concern, because significant levels are present in the environment (Degen and Bolt, 2000). The industrial chemical bisphenol A (BPA; used to make polycarbonate plastics and epoxy resins), naturally occurring plant estrogens (e.g., zearalenone), and the potent synthetic pharmaceutical estrogen diethylstilbestrol (DES) are some examples of the more prevalent environmental xenoestrogens of toxicological interest (Degen and Bolt, 2000;Juberg, 2000;Safe, 2000).…”

“…The industrial chemical bisphenol A (BPA; used to make polycarbonate plastics and epoxy resins), naturally occurring plant estrogens (e.g., zearalenone), and the potent synthetic pharmaceutical estrogen diethylstilbestrol (DES) are some examples of the more prevalent environmental xenoestrogens of toxicological interest (Degen and Bolt, 2000;Juberg, 2000;Safe, 2000). Although the potential hazard to human health from exposure to environmental xenoestrogens has not been conclusively determined (Degen and Bolt, 2000;Juberg, 2000;Safe, 2000), significant reproductive and associated anomalies in wildlife have been attributed to their exposure to xenoestrogens (Juberg, 2000), raising a significant health concern for humans.…”

“…Much of the focus on xenoestrogens has been on the disruption of reproductive function (Degen and Bolt, 2000;Juberg, 2000;Safe, 2000). However, as noted above, sex hormones also have well documented physiological effects on nonreproductive tissues such as the kidney, which contain receptors for both testosterone and estrogen (DeVries et al, 1972;Stefani et al, 1994).…”