The FDA states that microwave-safe plastic wraps, wax paper, cooking bags, parchment paper and white microwave-safe paper towels are safe to use. The FDA advises consumers to use products as intended including: use plastic containers only for their intended purpose; don’t reuse carry-out containers, margarine tubs and other containers not specifically designed for the microwave or freezer; discard single use microwave containers after you use them; and make sure microwave-safe plastic wrap is placed loosely over food so that steam can escape and it does not come in direct contact with your food.

Substances used to make plastic can indeed leech into your food, but the FDA has assessed the minute levels were found to be within a safe level, and those levels don’t include leeching dioxin. Dioxins are not in food-safe plastic or in plastic wrap and are not formed in the microwave.

Hormonal mimics

But there may still be reason to fear that leeching plastic, even if it isn’t leeching dioxin.

“Several European studies found that many plasticizers migrated from plastic containers and wraps into foods as they were heated in microwave ovens. Some of the chemicals were absorbed in high quantities (several hundreds of milligrams per kilogram food),” Dr. Rolf Halden, assistant professor in the Department of Environmental Health Sciences and the Center for Water and Health at the Johns Hopkins Bloomberg School of Public Health, said in an interview with The Office of Communications and Public Affairs. “The amount of chemical absorbed by the food depended on the temperature of the container and food, the duration of the heating, the type of plastic used and its initial plasticizer content, as well as the type of food being heated.

“As a general rule, the fattier the food, the more of the chemicals potentially can be absorbed and retained by it.”

The chemicals in question are phthalates “which are environmental contaminants that can exhibit hormone-like behavior by acting as endocrine disruptors in humans and animals,” Dr. Halden said. “These ‘synthetic hormones’ may pose a special risk to susceptible populations such as children, who are more vulnerable because they are still developing. But again, it’s not clear how much exposure to these chemicals is occurring.”

So should we be worried?

“In general, most studies of the kind are based on very high concentrations and/or very levels of exposure that simply cannot occur within the real world setting (i.e., no one can actually consume 50,000 ounces of water each day from water bottles left out in the sun),” assures Dr. Richard Dowell, a neuropsychologist at Evangelical Community Hospital. “The studies simply identify the potential negative impact of a material by exaggerating the dose. However, the actual risk to humans is rarely, if ever, known because exposures are so (relatively speaking) small.

“So, while there may be a risk,” Dowell added, “it is very small. You probably would be better served to worry about being injured in a motor vehicle accident, about dying from use of alcohol while driving, about the negative effects of cigarette smoking, about being killed or having your child killed in Iraq, about the senseless $12 billion a month we spend on the war in Iraq while our gas prices climb and our country is less safe than four years ago.”

If you’re still concerned and you want to minimize your exposure to these chemicals, the solution is simple: Recycle the plastic and use glass, ceramics and stainless steel containers instead.