Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Rubber Lid concerns

I love everything about this mug. i use it to store ans reheat soups for lunch at work. My concern is the vented lid. It aborbs stains very easily and has a VERY strong "pastic chemical" smell to it. I can't find out what this is made of but I question if it is safe to be in contact with foodstuff, especially heated foods.