So-called "microwave-safe" plastic actually leaches toxic Bisphenol-A (BPA), according to a recent report in the Journal Sentinel, a newspaper in Milwaukee, Wisconsin, that commissioned lab tests of 10 products, all of which released the chemical in potentially toxic amounts. Products included frozen microwaveable meals, which were heated as directed on their labels, plastic food storage containers labeled "microwave-safe," plastic baby bottles and canned foods, including baby formula and baby food.

Some of the products would be expected to contain BPA, such as a Rubbermaid Premier container with a #7 recycling code, which includes polycarbonate plastic, known to be made with BPA. But to everyone's surprise (including ours), BPA was also found to leach from containers with recycling #s 1, 2 and 5. This flies in the face of standard advice for avoiding BPA.

No need to panic and toss all your plastics. But we do suggest not heating food, and especially not baby's, in any kind of plastic bottle or dish, given the National Toxicology Program's expression of concern about the developmental risk of exposures to the very young. Kudos to our consumer sentinels at the Sentinel Journal, whose report has spurred federal and state lawmakers to start calling for the elimination of the controversial chemical from food and drink containers.

This article originally appeared in Plenty in November 2008. The story has since been added to MNN.com. Copyright Enrivon Press 2008

Microwaves and plastics shouldn't mix
Whether it's marked "microwave-safe" or not, using plastic in the microwave is not a good idea.