Wednesday, March 28, 2012

Toxic Chemicals in Food Packaging

I have been working on a post about the potential dangers of conventional nonstick cookware. The chemicals of concern associated with nonstick cookware are a family of chemicals called perfluorinated compounds (PFCs) and, specifically, one form of PFC, perfluorooctanoic acid (PFOA).

But after researching PFCs and PFOA, it appears that other sources of exposure to these toxic chemicals are likely as much, or more, of a threat to our health than exposure to conventional nonstick cookware. In particular, certain food packaging materials made of PFCs appear to migrate into food, enter into the bloodstream and break down into PFOA and other toxic chemicals.

Some background about these chemicals: PFCs have a unique ability to repel oil and water; they are used to make materials stain- and stick-resistant.  These chemicals are used in the manufacture of greaseproof food packaging including microwave popcorn bags, fast food wrappings, pizza boxes and candy bar wrappers. They are also used to make stain-resistant clothing, carpets and soft furnishings. 

PFCs are dangerous because they accumulate in our bodies and remain there for a very long time.  A 2009 report by the CDC found PFOA in the blood of nearly every one of over 2000 participants, indicating that PFOA exposure is widespread in the U.S. population.  PFCs persist in the environment and do not break down. And they are toxic--PFOA was deemed a likely human carcinogen by an EPA Science Advisory Board; it is also suspected of causing reduced fertility, poor birth outcomes and problems with the thyroid gland.

In addition, a study published in the Journal of the American Medical Association in January found that exposure to PFCs may weaken children's responses to vaccines, reducing the effectiveness of the vaccines. The study suggests that these chemicals are toxic to the immune system.

In 2006 Dupont, the manufacturer of Teflon, and 7 other companies entered into an agreement with the EPA to reduce the content of PFOA in consumer products by 95 percent by 2010, and to work toward eliminating it from consumer products by 2015. Dupont says that as of January 2012, it no longer uses PFOA to manufacture nonstick coatings for cookware. 

However, many experts agree that the crux of the PFOA problem is not nonstick cookware, but a class of chemicals called fluorotelomers which are used to impart stain and grease resistance to food packaging, carpets and textiles. Nena Baker, in her book The Body Toxic, suggests that DuPont, the manufacturer of Teflon, allowed nonstick cookware to take the public relations heat and serve as a distraction from fluorotelomers and their potentially central role in PFOA exposure. DuPont manufactures a whole host of fluorotelomer products.

The fluorotelomers used in food packaging are not made with PFOA, however, PFOA is an unintended byproduct of the manufacturing process.  But of even more concern, the fluorotelomers migrate into food and once they are in our bodies metabolize and break down into PFCs, including PFOA. And as noted above, once in our bodies these chemicals remain there for a very long time.

In 2005, the FDA published a study of the migration of fluorotelomers from food packaging to food. The study investigated microwave popcorn bags, which have the most grease-repelling fluorotelomer coatings of any food wrappings. The study found that a significant percentage of the fluorotelomers migrated from the bags to the popcorn oil. Once in the body, the fluorotelomers metabolize directly into PFOA and also metabolize into intermediate compounds that then also break down into PFOA.

A more recent study, published in 2010 found that dangerous chemicals in fast food wrappers and microwave popcorn bags (fluorotelomer-based products called PAPs) are a  potentially significant source of PFOA exposure in humans.

To reduce your exposure to dangerous PFCs:
  • Stay away from microwave popcorn.  Pop your popcorn on your stove.
  • Avoid greasy packaged and fast food. Packages such as pizza boxes, french fry boxes and fast food wrappers can contain PFCs.
  • Don't use paper plates; they can be coated with PFCs.
  • Avoid stain-resistant treatments on new carpets or furniture. According to the CDC, the presence of PFCs in carpet treatments could be an important source of exposure to these dangerous chemicals, especially for children.
  • Avoid nonstick cookware. If you do use it, be careful not to heat to above 450 degrees and discard any pans if the coating starts to flake or deteriorate.
I'm still looking into the new non-PFOA nonstick cookware and alternatives to nonstick, so stay tuned for a post about that.