bisphenol-A Commonly called BPA

In the chemical family: Bisphenol A & BADGE

Bisphenol a (BPA), a synthetic estrogen used to harden polycarbonate plastics and epoxy resin, is the focus of a growing number of research studies and legislative actions. An estimated 6 billion pounds of BPA are produced globally annually, generating about $6 billion in sales. It is fabricated into thousands of products made of hard, clear polycarbonate plastics and tough epoxy resins, including safety equipment, eyeglasses, computer and cell phone casings, water and beverage bottles and epoxy paint and coatings. But BPA-based plastics break down readily, particularly when heated or washed with strong detergent.

Trace BPA exposure has been shown to disrupt the endocrine system and trigger a wide variety of disorders, including chromosomal and reproductive system abnormalities, impaired brain and neurological functions, cancer, cardiovascular system damage, adult-onset diabetes, early puberty, obesity and resistance to chemotherapy.

In March 2007, Environmental Working Group published a ground-breaking study documenting that BPA had leached from epoxy can linings into more than half the canned foods, beverages and canned liquid infant formula randomly purchased at supermarkets around the country. The EWG study, the first of its kind, helped explain why the U.S. Centers for Disease Control and Prevention (CDC) had found detectable levels of BPA in the urine of 93 percent of Americans over the age of six. In the absence of any U.S. regulation on BPA contamination of food, EWG has published an online guide to baby-safe bottles and formula.

n September 2008, the National Toxicology Program found that BPA at current human exposure levels may be toxic to the brain, behavior and prostate gland of fetuses, infants and children.

Since then, manufacturers like Nalgene, Camelbak and Playtex offered non-BPA bottles, and Wal-Mart, Toys"R"Us and other retail giants discontinued sales of BPA-based plastic baby bottles, sippy cups and other food containers. Six major companies -- Avent, Disney First Years, Gerber, Dr. Brown, Playtex and Evenflow -- have stopped using BPA-based plastic in baby bottles for the U.S. market.

In January 2010, the federal Food and Drug Administration shifted its posture and no longer asserts that trace BPA contamination in food and beverages is safe. The agency has launched a new investigation of low-dose BPA risks and is encouraging industry to develop BPA-free can lining.

Food containers are not the only source of human BPA exposure. In July 2010, EWG made public laboratory tests finding high levels of BPA on 40 percent of receipts sampled from major U.S. businesses and services, including outlets of McDonald's, CVS, KFC, Whole Foods, WalMart, Safeway and the U.S. Postal Service. The chemical is used to coat some thermal papers used in receipt printers.

For a timeline of the BPA controversy, click here.

For a fact sheet on recent BPA, research, click here.