Concerns about toxic bottles and other consumer goods have led to new plastics—but we don't know much about them
Bisphenol A (BPA)—the once-obscure chemical building block of polycarbonate plastics, the epoxy resins that line many food and beverage cans, and of the coatings that make inks appear in most cash register receipts—is now almost a household word. But familiarity with the chemical has grown not because BPA is used in countless everyday products, but because of its potential adverse health effects, in particular its ability to act as an endocrine-disrupting chemical.
As a result, many major manufacturers of baby bottles, toddlers' drinking cups, and reusable water bottles—among other products—have switched to "BPA-free" materials. A number of prominent retailers in the U.S. and abroad are doing the same. So the question arises: What are these BPA-free materials, and who's making sure they're safe?
As scientific evidence of BPA's biological activity grows, the search for alternatives becomes more imperative. While the polymers BPA creates are strong, they easily release the substance, which can get into our bodies not only through contact with BPA-laden products themselves but also through food, dust, and air. Potential adverse effects—which can occur at very low levels of exposure—include disrupted genetic signaling and hormone activity that can lead to diabetes; obesity; impaired reproductive, developmental, neurological, immune, and cardiovascular system function; and certain cancers. Of particular concern are the effects of BPA on infants and children. BPA eventually does break down, but the chemical is in so many products that it is virtually ubiquitous. The Centers for Disease Control and Prevention has found BPA in more than 90 percent of the Americans it has tested.
The degree to which BPA poses a direct health risk continues to be debated. But China, Canada, Japan, the European Union, more than half a dozen U.S. states, the District of Columbia, and several other local and national governments have already restricted some uses of BPA, particularly in children's products, and this year about 17 states are expected to introduce similar legislation. So even if BPA is less of a risk than many people think, demand for alternatives is increasing. While there are currently no federal restrictions on BPA use, both the U.S Environmental Protection Agency (EPA), which has labeled BPA "a chemical of concern," and the Food and Drug Administration (FDA) have issued statements of support for the use of BPA alternatives.
So what are these BPA-free materials and what do we know about them?
Glass, ceramics, and stainless steel are alternatives for some uses of polycarbonates, but plastics have obvious attractions. And avoiding many uses of BPA—can linings, paper—will require some kind of new polymer, or products will have to be redesigned to perform as desired without, for example, a plastic liner or coating. Companies are pursuing both strategies.
Then there are the new plastics on the market for BPA-free bottles, can liners, and other such products. The Environmental Protection Agency (EPA) also has an effort underway through its Design for Environment program to examine the alternatives to the BPA-based thermal papers used in receipts, currency, and other similarly printed papers. But because the U.S. system of regulating chemicals relies primarily on information supplied by a material's manufacturer, we know relatively little about these new plastics.
For example, among the more widely used plastics now marketed as "BPA-free" is Tritan copolyester, made by the Eastman Chemical Company. According to Eastman, sales of Tritan copolyester quadrupled between March of 2009 and March 2010. But currently the available information about this product's chemistry comes from its manufacturer. The Eastman Chemical website offers Material Safety Data Sheets (MSDS) for 23 different compounds sold under the Tritan copolyester name (each intended for different product applications). The MSDS sheets list no toxicity data and note that the compounds' environmental effects have not been tested.
In May 2010, Eastman released test results showing several of the chemicals that make up Tritan copolyester to be free of both BPA and any endocrine-disrupting activity. But no other environmental or toxicity information or the final product's other chemical ingredients is included.
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The point is not to single out the Eastman Chemical Company or Tritan copolyester, which may be entirely environmentally benign, but to highlight the dilemma we're in when it comes to assessing the safety of new materials. The same could be said of any number of new materials used in hundreds of consumer products. Under the Toxic Substances Control Act (TSCA), the U.S. law that regulates chemicals in commerce, it's entirely permissible to launch a new material into high-volume production without disclosing its precise chemical identity or any information about its toxicity. This makes it impossible for the public to assess product safety independently of manufacturer claims. And currently, despite EPA and FDA policies that support "safe" alternatives to a chemical of concern like BPA, neither federal agency conducts safety testing of new materials destined for consumer products before they come on the market.
The National Institutes of Health is supporting research into the health effects of BPA with $30 million in grants. But there is no comparable research examining products marketed as BPA alternatives. The EPA's Design for Environment effort is examining literature provided by manufacturers of alternate materials but is not currently conducting or commissioning any safety testing of its own. The EPA has outlined an "chemical action plan" that involves assessing the environmental and health impacts of bisphenol A and strategies to reduce exposure, but the only materials the agency can include in its Design for Environment program are the non-food contact products over which it has jurisdiction. Food contact products are regulated by the FDA, which has no program to develop or test materials.
What all this means is that while U.S. federal policy supports alternatives to BPA—and we're using products containing these new materials at increasing volume—we actually know very little about them and lack a system that would provide independent assessment of new materials before they're in our homes. With demand growing for safe plastics, it's clear that we need a better and more proactive way of ensuring their safety—and ours.
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