Hormone disruptor

W.R. Kelce, E. Monosson, P. Gamcsik, S.C. Laws and L.E. Gray Jr., Environmental hormone disruptors Evidence that vinclozolin developmental toxicity is mediated by antiandrogenic metabolites. Toxicol. Appl. Pharmacol. 126 276, 1994. 

Dysfunction of the endocrine system could be due to either hyperfunction (excessive hormone production or responses) or hypofunction (insufficient hormone production or responses). Environmental chemicals that have the potential to perturb the endocrine system are known as endocrine or, synonymously, hormone disruptors. 

See also Androgens Diethylstilbestrol Environmental Hormone Disruptors Radiation Toxicology, Ionizing and Nonionizing Reproductive System, Female Reproductive System, Male Toxicity Testing, Reproductive. 

The discussion of EDCs to this point has addressed responses to single chemicals. Mixtures of hormone disruptors have not been well studied, but... 

DeVito M, Biegel L, Brouwer A, Brown S, Brucker-Davis F, Cheek AO, Christensen R, Colborn T, Cooke P, Crissman J, Crofton K, Doerge D, Gray E, Hauser P, Hurley P, Kohn M, Lazar J, McMaster S, McClain M, McConnell E, Meier C, Miller R, Tietge J, Tyl R (1999) Screening methods for thyroid hormone disruptors. Environ Health Perspect 107(5/407-415... 

Kelce, W. R, Mouosson, E., Gamesik, M, P, Laws, S. C., and Gray. L. E., Jr. (1994). Environmental hormone disruptors Evidence that vinclozolin develupmenial toxicity is mediated by aniiandrogenic meiahoUte.s. Ta.xicoi. AppL Pharmacol. 126, 276-285. 

H M, the world s second-largest clothing retailer, first entered Greenpeace s sights after investigations revealed links between major fashion brands and factories that were discharging hazardous chemicals, including hormone-disruptors such as nonylphenol ethoxylates into China s rivers. 

Recently, attention has focused on the potential hazardous effects of certain chemicals on the endocrine system because of the abihty of these chemicals to mimic or block endogenous hormones, or otherwise interfere with the normal function of the endocrine system. Chemicals with this type of activity are most commonly referred to as endocrine disruptors. Some scientists believe that chemicals with the ability to disrupt the endocrine system are a potential threat to the health of humans, aquatic animals, and wildlife. Others believe that endocrine disrupting chemicals do not pose a significant health risk, particularly in light of the fact that hormone mimics exist in the natural environment. Examples of natural hormone mimics are the isoflavinoid phytoestrogens (Adlercreutz 1995 Livingston 1978 Mayr et al. 1992). 

The chemical structure of the substances capable of interacting with a determinate nuclear receptor is tremendously varied. For now no pattern exists that permits one to assure that a particular substance is going to interact with the receptor to produce an agonist or antagonist effect. In recent years the concept of endocrine disruptors has been introduced to describe the substances that are capable of modifying the endocrine equilibrium. Some of them act by binding with nuclear hormone receptors, while others interfere with the processes of regulation of hormone secretion (Lathers 2002 Melnick et al. 2002 Nakata 2002 Powles 2002 Brown et al. 2002 Sonnenschein et al. 1998). 

EC. 1999. Communication from the Commission to the Council and the European Parliament on Community strategy for endocrine disruptors, a range of substances suspected of interfering with the hormone systems of humans and wildlife. COM (1999) 706 Final. http / ec.europa.eu/environment/docum/99706sm.htm... 

Depending upon the circumstance and desired effects, endocrine-disrupting chemicals can be either good or bad. The endocrine system is a finely balanced system responsible for fertility and many of the feminine and masculine traits we are all familiar with. Endocrine disruptors are used by millions of women in the form of the pill to control fertility. Chemicals in birth control pills subtly manipulate the endocrine system to reduce fertility. Unfortunately, we now know that many chemicals are capable of influencing the endocrine systems. When these chemicals, such as DDT and TCDD, are released into the environment, they reduce the fertility of wildlife. Exposure to endocrine disruptors is linked to decreased fertility in shellfish, fish, birds, and mammals. Endocrine disruptors such as nonylphenol have been shown to feminize male fish, interfering with reproduction. Some studies have also linked exposure to endocrine disruptors to decreases in human male sperm count. Ironically, urinary metabolites of the birth control pill as well as the female hormone estrogen pass through waste treatment plants and are released into the aquatic environment, where even small concentrations cause feminization of male fish. 

The subject of endocrine disruptors and fear of chemicals (chemophobia) has been addressed in several recent books on both sides of this contentious issue. Our Stolen Future Hormone... 

Deception Hormonal Chaos and The Feminization of Nature— Our Future at Risk chronicle the perceived, predicted, and observed problems associated with endocrine disruptors.50 Skepticism regarding the human impact of environmental contaminants has been discussed in several books including The Skeptical Environmentalist and Naturally Dangerous Surprising Facts About Food, Health and the Environment,51 and John Stossel (ABC television) remains a consistent skeptic with his features on junk science. 

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