The extra ingredient? Government agencies and environmental advocacy groups are questioning the safety of a chemical in food packaging materials.
Some toxic chemicals may appear where consumers least expect them: on fast-food packaging, says Lauren Sucher, communications director of the nonprofit Environmental Working Group (EWG) of Washington, D.C. Fluorinated telomers, a type of very small polymer with Teflon-like properties, keep grease from seeping through paper and cardboard packaging such as french fry cartons and pizza boxes. And although the telomers themselves may be innocuous in normal use, they can break down upon ingestion into perfluorooctanoic acid (PFOA). PFOA also is a component in the manufacturing process of fluoropolymers and can be present in trace amounts in fluorinated telomers.
Although the human health effects of PFOA are still unconfirmed, the chemical’s ubiquity is cause for concern. Studies submitted in 2001 by the 3M Company (then a PFOA manufacturer) to the government found the chemical in the blood of 96% of 598 children tested in 23 states and the District of Columbia, Sucher says. The EWG is concerned that people could ingest PFOA that transfers from packaging to food, and that as the telomers break down in landfills and other disposal channels, PFOA could enter the environment.
Identifying exactly which products use fluorinated telomers is no simple matter. These telomers aren’t regulated, and most packaging doesn’t identify their presence. Typically they are applied at paper mills, which supply coated paper to manufacturers that in turn supply packaging to restaurants.
In March 2003, the U.S. Environmental Protection Agency (EPA) initiated a priority review under the Toxic Substances Control Act. The review was based on limited data showing some presence of PFOA in people’s blood and studies involving laboratory animals that showed potential developmental and reproductive toxicity, liver toxicity, and cancer. In a 14 April 2003 Federal Register notice, the EPA released a preliminary risk assessment for PFOA and outlined a public process for further developing the assessment.
In July 2003 the EWG asked nine of the country’s largest restaurant chains–Burger King, KFC, Krispy Kreme, McDonald’s, Pizza Hut, Starbucks, Subway, Taco Bell, and Wendy’s–to report on the types of chemical coatings used in their products. As of October 2003, none of the chains had responded directly to the EWG. But some–such as McDonald’s, which does use fluorinated telomers for certain products, and Krispy Kreme, which doesn’t, and instead uses clay-based products exclusively–have responded to press inquiries following publicity of the EWG’s request.
“A question we have to answer,” says EPA public affairs officer David Deegan, “is exactly how people are being exposed to PFOA.” Scientists are scrambling to find how the chemical finds its way into the bloodstream. Deegan says it’s unknown whether food packaging is actually a source of exposure, and that PFOA hasn’t been detected in such wrappings.
But Sucher says there is precedent for perfluorochemicals used in paper products ending up in human blood. The internal monitoring studies done by the 3M Company and reviewed by the EPA show that at least one perfluorochemical metabolite specific to paper protection applications is readily found in people, including 85% of the children tested. Sucher says perfluorochemicals such as PFOA have a half-life of an estimated 4.4 years in the human body.
“We are looking at paper applications as just one of several possible pathways to PFOA exposure [in] the environment,” says Michelle Reardon, a spokesperson for DuPont, a current PFOA manufacturer. But, she says, many other pathways are under investigation as well. Fluorinated telomers are also used in the manufacture of fire-fighting foam, leather products, carpeting, garments such as stain-resistant trousers, and many other applications. Sorting out these potential sources and pathways of PFOA exposure is one of the priorities of the EPA’s review, Deegan says.
In the meantime, Sucher says, environmental groups hope that companies, especially those in the food business, will move away from products with the potential to spread PFOA. “They have every right to use them,” she says. “They are abiding with federal law. On the other hand, as a public health advocacy group, we want them to try to find alternatives.”