Supporting high quality research by the nation's leading scientists and engineers to improve EPA's scientific basis for decisions on national environmental issues.Endocrine disruption: Fact or urban legend? Highlights. Purported EDCs in personal care products include 4- MBC (UV filter) or parabens that showed oestrogenic activity in screening tests, although regulatory toxicity studies showed no adverse effects on reproductive endpoints. Hormonal potency is the key issue of the safety of EDCs. Oestrogen- based drugs, e. Additive effects of EDs are unlikely due to the multitude of mechanisms how substances may produce a hormone- like activity; even after uptake of different substances with a similar mode of action, the possibility of additive effects is reduced by different absorption, metabolism and kinetics. Abstract; About This Article; Supplemental Material; Background: Laboratory and human studies raise concerns about endocrine disruption and asthma resulting from exposure to chemicals in consumer products. In this activity you will learn how environmental “surprises” and scientific uncertainty related to endocrine disruptors influence the decisions that people make. EPA implements screening, testing and research programs to gather information the Agency uses to evaluate possible endocrine effects associated with the use of a chemical. EPA takes appropriate steps to mitigate any related. We review the international definitions of endocrine disruptors (EDs). We discuss the association of EDs with the testicular dysgenesis syndrome. We discuss the pivotal role of potency in the safety assessment of EDs. Topics include the demographics of autoimmunity; the role that environmental toxins can play in autoimmune diseases; how the endocrine system and hormone balance can affect autoimmunity; a review of laboratory tests that can. BPA exploded into the headlines in 2008, when stories about 'toxic baby bottles' and 'poison' packaging became ubiquitous. Good Morning America issued a 'consumer alert.' The New York Times urged Congress to ban BPA in baby. International Acceptance: BG1Luc ER TA Test Method: Endocrine disruptor screening assay: ICCVAM (2012) OECD TG 457 (2012) Draft Performance Standards for TG 457 (2012) H295R. There is an increasing interest in micropollutants in the environment that can interfere with the endocrine system, affecting health, growth and reproduction of animals and humans. These substances are known as. Bisphenol A (BPA) is an organic synthetic compound with the chemical formula (CH 3) 2 C(C 6 H 4 OH) 2 belonging to the group of diphenylmethane derivatives and bisphenols, with two hydroxyphenyl groups. It is a colorless solid. This is supported by a number of studies on mixtures of chemical EDCs. Overall, despite of 2. Abbreviations. Bf. R, Bundesamt f. Therefore, it is not surprising that high doses of industrial chemicals, such as phthalates, chlorinated compounds as well as numerous other substances were also found to adversely affect reproduction in laboratory animals. From the early 1. Thus a novel category of potentially hazardous substances, endocrine disruptors or endocrine modulators was born, although the exact definition of the meaning of these terms is still debated and somewhat unclear ( Foster and Agzarian, 2. Indeed, the European Union, the WHO and the US EPA employ slightly different definitions thereby adding to the breadth of interpretational room for any data generated. Special concerns have been raised by some scientists and environmental activists that human exposure to hormonally- active ingredients used in personal care products/cosmetics with potential hormonal activity, such as parabens, phthalates or certain ultraviolet filters, may affect human endocrine systems and pose a risk to human health (Witorsch and Thomas, 2. For example, it has been suggested that human exposure, in particular pre- natal exposure of the human foetus, to such substances may affect human semen quality, produce or contribute to male infertility, birth defects in male infants, breast and testicular cancers, obesity and other adverse health effects. Given that chemicals with potential hormone- like activity, in particular personal care product ingredients, have a minute potency when compared with that of actual, mammalian hormones, such as oestradiol, novel hypotheses were developed that human exposure to mixtures of a multitude of weakly active substances may produce additive or even synergistic effects and yet pose a risk to human health (Witorsch, 2. Myers et al., 2. 00. Considering these hypotheses, we attempted to summarise the present state of knowledge on Endocrine disruptors and to review whether ingredients of personal care products/cosmetics may produce adverse human health effects secondary to endocrine disruption. What are “Endocrine disruptors”? The Endocrine system is the term for multiple and diverse hormonal systems in the mammalian organism, such as thyroid hormones, hormones originating from the pancreas, ovaries, testes, adrenals or the brain. There have been a number of definitions of what is an “Endocrine disruptor” (ED). The most commonly agreed are the following: An ED is an exogenous substance that causes adverse health effects in the intact organism or its progeny, secondary/consequent to changes in endocrine function“( Weybridge, 1. A similar definition has been chosen by the World Health Organisation's International Program on Chemical Safety: An endocrine disrupter is an exogenous substance or mixture that alters function(s) of the endocrine system and consequently causes adverse health effects in an intact organism, or its progeny, or (sub)populations ( WHO/IPCS, 2. A joint expert group of the German Bundesamt fuer Risikobewertung (Bf. R) and UK health authorities (UK- Bf. R) regulatory expert group proposed an identical definition: An ED is an exogenous substance or mixture that alters function(s) of the endocrine system and consequently causes adverse health effects in an intact organism, or its progeny or (sub) populations ( Bf. R, 2. 01. 1). The most recent definition issued by the EU is that an ED is an exogenous substance that causes adverse health effects in an intact organism, or its progeny, secondary to changes in endocrine function ( EU, 2. European Food Safety Agency (EFSA, 2. The US EPA defined EDC as follows: Endocrine disrupting chemicals (EDCs) have been defined as exogenous agents that interfere with the production, release, transport, metabolism, binding, action, or elimination of the natural hormones in the body responsible for the maintenance of homeostasis and the regulation of developmental processes ( EPA, 2. It is important to note that all major international definitions stipulate that an EDC must cause adverse effects via an endocrine- mediated mechanism in an intact organism. A common definition of what constitutes an adverse effect has been proposed by the Bf. R/UK expert group, the WHO IPCS, ECETOC and independent authors (Bf. R, 2. 01. 1, WHO/IPCS, 2. ECETOC, 2. 00. 9 and Lewis et al., 2. All current definitions agree that the definition of an “adverse effect” means toxicity, i. Therefore, only a substance that produces toxicity in an intact organism via a hormonal or hormone- like mechanism represents a genuine ED.
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