The U.S. Food & Drug Administration (FDA) has determined that plastics used for packaging food must be of greater purity than plastics used for the packaging of non-foods. As a result, this type of plastic is referred to as food grade plastic. Food grade plastic may not contain dyes or recycled plastic that has been considered harmful to humans. Recycled plastic can be used to create food grade plastic food storage containers, however. When using food grade plastics to store your foodstuffs, note that highly acidic foods like tomatoes or foods that contain alcohol and/or fats may leech plastic additives from the packaging or container into the food. Be sure to select only FDA-approved plastic food containers.