Microwaving Plastic

Dear Lisa

I received an email from a friend stating that a doctor on T.V. explained that microwaving with plastic releases toxins into our bodies that can cause cancer. Is this true? I am worried that I have been harming my kids because I microwave in plastic all of the time.

“Worried about cancer in N.J.”

Dear “Worried about cancer”,

It has been known for a long time that, “Hot food melts some plastics, such as margarine tubs, causing migration of package constituents. (1) “It’s true that substances used to make plastics can leach into food, but as part of the approval process, the FDA considers the amount of a substance expected to migrate into food and the toxicological concerns about the particular chemical.” The agency has assessed migration levels of substances added to regulated plastics and has found the levels to be well within the margin of safety based on information available to the agency. The FDA will revisit its safety evaluation if new scientific information raises concerns (2).

What we don’t know is what levels of which chemicals that are leached out of the plastic into the foods cause cancer in humans? How many years of exposure are needed in order to reach a level that puts someone at risk? What type of people are more susceptible to the accumulation of these chemicals? What other medical conditions may be caused by the accumulation of these chemicals in the body?

It is clear that future research needs to be done in order to answer these questions. In the mean time, parents can take one of two courses of action. Continue to prepare your child’s meals microwaved in plastic until it is proven that it is not safe or stop preparing meals microwaved in plastic until repeated research studies prove that it is safe. Before you make this decision ask yourself these questions; Are the misshapen, stained plastic containers that I use microwave safe? Does the plastic wrap that I buy state that it is safe to be used in the microwave?

The one thing that the experts do agree upon is that consumers should use plastics for their intended purpose and in accordance with directions. “Microwave-safe plastic wrap should be placed loosely over food so that steam can escape and should not directly touch your food.” (2) Rolf Halden, PhD, PE, assistant professor at the Johns Hopkins Bloomberg School of Public Health states, “If you are cooking with plastics or using plastic utensils, the best thing to do is to follow the directions and only use plastics that are specifically meant for cooking. Inert containers are best, for example heat-resistant glass, ceramics and good old stainless steel.”(3 )

References:
(1)Farley, D. Keeping Up with the Microwave Revolution. FDA Consumer Magazine. 1992; December.
(2)Meadows, M. Plastics and the Microwave. FDA Consumer Magazine. 2002; November.
(3)Johns Hopkins Bloomberg School of Public Health. Public Health News Center. Researcher Dispels Myth of Dioxins and Plastic Water Bottles: 2006. Available at
http://www.jhsph.edu/PublicHealthNews/articles/Halden_dioxins.html
Accessed May 10, 2006.

Lisa Kelly R.N., P.N.P.,C.
Certified Pediatric Nurse Practitioner

Pediatric Advice For Parents