Several animal studies show adverse effects, such as abnormal reproductive development, at exposures of 2.4 micrograms of BPA per kilogram of body weight per day. Our food-safety scientists recommend limiting daily exposure to one-thousandth of that level, or 0.0024 micrograms per kilogram of body weight, following established practices to ensure an adequate margin of safety.
An FDA special scientific advisory panel reported in late 2008 that the agency's basis for setting safety standards to protect consumers was inadequate and should be re-evaluated. A congressional subcommittee determined in 2009 that the agency relied too heavily on studies sponsored by the American Plastics Council. BPA, a building block of plastics, is a component of epoxy resin used in cans and packaging. "The FDA's reliance on industry studies in determining BPA's safety must be re-evaluated in light of clear signs industry is willing to mislead the American people on this public-health issue," said Rep. Bart Stupak, D-Mich., chairman of the House Energy and Commerce Committee's Oversight and Investigations Subcommittee. Bills are pending in Congress that would ban the use of BPA in all food and beverage containers.
Industry has been waging a fight against new regulations. The American Chemistry Council says on its Web site: "The weight of scientific evidence clearly supports the safety of BPA and provides strong reassurance that there is no basis for human health concerns from exposure to BPA." The chemical was first marketed in the 1940s as a plastic component and by the 1960s was used in almost all can linings to extend shelf life. Now it is one of the highest-volume chemicals in the world; at least 7 billion pounds are produced annually for use in countless products, including dental sealants, PVC water pipes, medical equipment, consumer electronics, and even cash-register receipts.
New evidence of the risks of BPA at low levels increases the concern about those multiple sources of exposure. "Our regulatory standards now are based on the outdated assumption that when you test a chemical's safety at high doses, the results also will reveal any risks occurring at low doses, but as hundreds of studies have now demonstrated, it doesn't work that way with estrogen-mimicking chemicals like BPA, which can have completely different and potentially more harmful effects at low doses," says Frederick vom Saal, a professor of developmental biology at the University of Missouri at Columbia and a leading researcher on BPA.