Popcorn lovers take note: microwave popcorn may be convenient, but it also may be hiding a potentially unhealthy substance, and it’s not the butter. It is perfluorooctanoic acid (PFOA), a synthetic chemical that is found in the lining of microwave popcorn bags.
According to the Environmental Protection Agency (EPA), PFOA is used by companies to make fluoropolymers, substances that have special properties such as the ability to resist fire, oil, grease, and water. This characteristic is highly desirable in substances that can be used to coat the inside of microwave popcorn bags to repel grease and moisture and the inside of non-pstick cooking utensils (Teflon®). When the chemicals used to line these bags are heated, some release PFOA, which an EPA scientific advisory panel has identified as a likely human carcinogen.
A study conducted by the Food and Drug Administration (FDA) used a technique called liquid chromatography-mass spectrometry to identify just how much PFOA migrates from a microwave popcorn bag into the popcorn. It found that a very small amount of the chemical did leach into the popcorn, but no warnings were issued about its health dangers. The FDA study did estimate that blood levels of PFOA from microwave popcorn may account for about 20 percent of the average amount found in the blood of Americans, which means consumers need to worry about more than microwave popcorn when it comes to PFOA.
PFOA has been linked with liver, pancreatic, and testicular cancer as well as reproductive disturbances in laboratory animals. It has also been found to sicken humans and birds when outgassed from overheating cooking vessels coated with Teflon. PFOA is known to accumulate and linger in the body once it is ingested.
But PFOA is not the only dangerous substance that could be lurking in your popcorn. An artificial butter flavoring called diacetyl was believed to be the cause of a rash of a potentially deadly respiratory disease that struck two dozen workers in a microwave popcorn plant in 2001. Although the National Institute for Occupational Safety and Health believed that exposure to the artificial butter flavoring was behind the disease that destroys lung tissue and for the fact that 130 plant employees had twice the national average rates of asthma and bronchitis, it still said it believed it was safe for people to eat microwave popcorn and other foods that used diacetyl.
For now, DuPont and other manufacturers have promised to phase out their use of PFOA by 2015 under an EPA voluntary plan. Since diacetyl is deemed safe by the FDA, no action is planned for this substance. To minimize exposure to PFOA, microwave popcorn lovers may want to choose another way to enjoy their popcorn, say with a hot-air popper or the traditional skillet and stove method of making popcorn.
Begley TH et al. Food Additives and Contaminants 2005 Oct 22 (10): 1023-31
Environmental Working Group
Healthierlife.uk.co, June 6, 2006