Here's what I found, from the USDA-
<div class="FTQUOTE"><begin quote>Containers & Wraps
Only use cookware that is specially manufactured for use in the microwave oven.
Glass, ceramic containers, and all plastics should be labeled for microwave oven use.
Plastic storage containers such as margarine tubs, take-out containers, whipped topping bowls, and other one-time use containers should not be used in microwave ovens. These containers can warp or melt, possibly causing harmful chemicals to migrate into the food.
Microwave plastic wraps, wax paper, cooking bags, parchment paper, and white microwave-safe paper towels should be safe to use. Do not let plastic wrap touch foods during microwaving.
Never use thin plastic storage bags, brown paper or plastic grocery bags, newspapers, or aluminum foil in the microwave oven.
Last Modified: April 3, 2006
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