Lidded plastic containers are convenient for leftovers, soups and other foods to be stored in the refrigerator and freezer. they can be washed in the dishwasher, on the top rack only. Do not, however, heat food in plastic, even plastic labeled “microwave safe,” and always let hot foods cool before putting them in plastic. When plastic is heated, it may leach potentially dangerous chemicals into food. Throw out or recycle visibly damaged, stained, or unpleasant-smelling plastic containers due to some concern that chemicals may also leach from scratches. Do not reuse plastic containers intended for one-time use, such as yogurt tubs.
Lidded glass containers are ideal for storing all sorts of foods, in the pantry, the refrigerator, and even the freezer. they are preferable to plastic containers because they are easier to clean, particularly when it comes to greasy residue, and will last for years, making them a much more economical choice. Before subjecting any class container to the extreme temperatures of the freezer or oven, however, be sure it is intended for this purpose. Brands such as Pyrex, for example, are specially designed for use in the freezer and oven. Ordinary glass will crack. If in doubt, leave it out. Most glass containers, unless they have a metallic trim or finish, are safe to use in the microwave, says a 40+year old Residential Cleaning Service in Evanston, Il