Along with refrigeration, modern packaging is considered to be one of the major contributors to the safety of the food we eat and serve our families each day. Food wrap is one of the many applications advances for plastic that has promoted the safe transportation, delivery and storage of food, from the steaks and chicken in the meat section of the grocery store, to the leftovers we keep fresh for a second meal. A number of plastics, including PVC (polyvinyl chloride), can be used for plastic food wrap.
For more than a decade, stories have circulated that there are dangers involved in using plastic food wrap to protect and store food because of allegations that plasticizers can migrate into food and cause harm. More recently, there has been e-mail traffic referring to the "dangers" of using plastic food wrap in the microwave. As the stories have been passed along, numerous inaccuracies have been introduced. One of the urban legends goes so far as to state that food wrap contains dioxin. In the anxiety stirred up by this issue, the clear benefits of plastic to the safety of food are forgotten, confusing consumers who want to do the right thing for their families.
Virtually all food packaging materials contain substances that can migrate into the food they contact, including the plasticizers used in plastic food wrap. Such substances are considered "food contact substances" by the U.S. Food and Drug Administration (FDA), which has regulatory authority over packaging materials that contact food, and must find them safe for their intended use before they can be marketed.
Contrary to recent news reports, PVC food wrap manufactured in the U.S. is not plasticized with phthalates; instead, a different kind of plasticizer di (2-ethylhexyl) adipate (DEHA) is commonly used. DEHA is listed by the U.S. government as a plasticizer that may be used in plastics that contact food.
The stories and e-mails that say DEHA has been shown to cause cancer in humans are incorrect. DEHA has been found to have a weak cancer causing effect at very high dose levels in female mice, by a biological mechanism very different from what happens in humans. Slight reproductive and developmental effects have been seen in rodents at very high DEHA levels much higher than any human would be exposed to through any realistic use of plastic food wrap.
What the FDA Says
The FDA recently published an article in its consumer magazine. It states that the level of plasticizer that might be consumed from plastic film is "well below the levels showing no toxic effect in animals." And it quotes one of its consumer safety officers as saying that the agency "has seen no evidence that plastic containers or films contain dioxins and knows no reason why they would." As for plastic bottles, no plasticizer of any kind is used in the kind of plastic most commonly used for water and soft drinks, known as PET. One oft-repeated claim that Johns Hopkins University has issued a warning about plastic water bottles has been denounced as a hoax by the university. For more information, please see http://www.plasticsmythbuster.org/.
As a practical matter, manufacturer's directions should always be followed, especially when dealing with food-related materials, plastic or otherwise. Any product, including plastic food wrap, no matter what its composition, should be microwaved carefully because its melting point may not be high enough to withstand high heat and it may melt on to the food.
The bottom line on food wrap is best summarized by the comments included on Center for Food and Nutrition Policy web site in 1999, "We...believe the benefits of using plastic wrap to protect food safety and quality on the shelf to far outweigh the imagined risks..."