Is it true that microwaving with plastic releases cancer causing dioxins into the food?
No. A popular Web rumor wrongly contends that plastics contain dioxins, which are a likely carcinogen. Some plastic wraps may, however, contain chemical plasticizers that add flexibility, and those can migrate into food when heated. The risks associated with consuming trace amounts of plasticizers are small. But more research is needed, so leave space between plastic wrap and food, or use a paper towel to cover your food instead. (Note that plastic containers not approved for microwave use can warp and leak potentially hazardous chemicals into the food.) Source: ConsumerReports.org Microwave Safety Web site: http://www.consumerreports.org/cro/appliances/kitchen-appliances/microwave-ovens/microwave-safety-9-06/overview/0609_microwave-safety_ov.
