By Mary Jane Dittmar
“Brominated flame retardants (BFRs), can mimic estrogen hormones and possibly disrupt the body’s endocrine system,” according research undertaken by the U.S. Department of Health and Human Services National Institutes of Health (NIH) News National Institute of Environmental Health Sciences (NIEHS).The study is online in Environmental Health Perspectives.
The study involved tetrabromobisphenol A (TBBPA), a widely used flame retardant, which was shown to cause tumors in rats and mice in data from a two-year bioassay study the National Toxicology Program (NTP) released earlier this year (CLICK HERE for the report).
Linda Birnbaum, Ph.D., director of NIEHS’ NTP, lead researcher, and an expert in flame retardants, noted, “The ability of flame retardants to bind to and inhibit estrogen sulfotransferase, an enzyme that metabolizes estrogen, could result in the body’s having too much estrogen.” The endocrine system controls and coordinates numerous functions, including growth and development, reproduction, response to stress, and energy levels.
The researchers used X-ray crystallography to build a 3-D model of the protein binding to flame retardants. Crystallography allows researchers to look at proteins at the atomic level. Birnbaum explained that the 3-D imaging capabilities enable researchers “to see the flame retardants binding, or attaching, to proteins like estrogens do.” She and her colleagues examined how TBBPA and a derivative of another flame retardant, tetrabromodiphenyl ether, or BDE-47, which is no longer produced in the United States, compared with the binding of estradiol, a naturally occurring estrogen, to the estrogen sulfotransferase.
Although many flame retardants are no longer produced in the United States, some BFRs are slow to break down and can persist in the environment. People are exposed to flame retardants through diet; consumer products in the home, car, and workplace; and house dust.
One of the objectives of conducting studies on how flame retardants affect bodily systems is that the industry will develop safer alternatives for those products now available that adversely affect the human body.
This NIH News Release is available online at:
<http://www.nih.gov/news/health/aug2013/niehs-19.htm>. For additional information on this topic, contact Robin Mackar, NIEHS, <e-mail:rmackar@niehs.nih.gov>
NIEHS supports research to understand the effects of the environment on human health and is part of NIH. For more information on environmental health topics, visit http://www.niehs.nih.gov.
References
Gosavi RA, Knudsen GA, Birnbaum, LS, Pedersen LC. “Mimicking of estradiol binding by flame retardants and their metabolites: a crystallographic analysis.” Environ Health Perspect; doi:10.1289/ehp.1306902 [online August 19, 2013].
National Toxicology Program. 2013. Tetrabromobisphenol A. Available: http://ntp.niehs.nih.gov/go/TS-M200033 [accessed August 12, 2013].
MARY JANE DITTMAR is senior associate editor of Fire Engineering and conference manager of FDIC. Before joining the magazine in January 1991, she served as editor of a trade magazine in the health/nutrition market and held various positions in the educational and medical advertising fields. She has a bachelor’s degree in English/journalism and a master’s degree in communication arts.
