Food-safe plastics are a different type and grade of plastics than those used in other commercial products, such as toy packaging. Food is stored in different types of plastics, according to the Institute for Agriculture and Trade Policy, and not following the recommended uses can make the plastic unsafe for food.
Plastic labeled as "food-safe" or used for food must meet the U.S. Food and Drug Administration's standards of a higher level of purity than that of regular plastic. Its packaging can contain recycled materials but must not have harmful chemicals or dyes. The food-safe plastic type must be suitable for the food it will contain; for example, a food-safe container made of plastic that does not withstand heat should not contain hot food.
Consumer products and packages use one of seven different types of plastic, but plastic items labeled as "food-safe" or used for food storage typically use one of only three kinds: polypropylene, polycarbonate and high-density polyethylene. Polypropylene does not bend or stretch easily and it can withstand hot items. Food holders with lids, such as yogurt containers, and common food storage containers use polypropylene.
Polycarbonate plastics do not stain easily and are commonly used in food storage items, but the plastic might leach bisphenol A, a harmful substance.
High-density polyethylene is resistant to seepage. It is found in containers for milk, juice and water; the inside of coolers; and large food-storage buckets.
No containers that have held holding chemicals, cleaning agents or "food-safe." Food-safe containers are porous, so items that are hazardous to humans could seep into the plastic.
Food should not be microwaved in a food or "microwave-safe" plastic container, according to the Institute for Agriculture and Trade Policy, because chemicals could leak into the food as the plastic is heated. Do not let plastic wrap -- typically made of polyvinyl chloride -- touch food as it cooks in a microwave, and instead use a paper towel to cover the food if possible. There is greater leaching of chemicals from plastics into fatty foods, according to the institute.
"One-time-use" plastics are not safe for reuse with food and liquids. Single-use water bottles and "throwaway" utensils, food containers and plates, although safe for food at first use, do not withstand repeated use or cleaning. Some types of single-use food plastics cannot tolerate hot or acidic foods without breaking down and leaching chemicals.
- Institute for Agriculture and Trade Policy: Smart Plastics Guide / Healthier Food Uses of Plastics
- Virtual Weber Bullet: What is Food Grade Plastic?
- WebMD: "Pots, Pans, and Plastics: A Shopper's Guide to Food Safety"; Matthew Hoffman, M.D.; December 2008
- University of Nebraska Cooperative Extension in Lancaster County: "Kitchen Food Safety: Bags, Bottles & Beyond"; Alice Henneman; Joyce Jensen; September 2004
- U.S. Food and Drug Administration: Recycled Plastics in Food Packaging