WOW....you all are so wonderful!! I appreciate your comments so much. I keep testing and testing in my microwave and the polyester doesn't get even warm. I've gone up to 10 minutes while watching closely.....I feel so sure they will not burn, but still am frightened by the comments that polyester will burn. I've never smelled any fumes either. I'm sure spilled food would burn. Maybe it's best to just tell them not to put it into the microwave, but that is what makes it so great.....Keep the comments coming...Love hearing from you all!!!!