Plastic containers are made of different textures, which have different purpose and application. And some of plastic containers are not suitable for containing food.
Frozen foods packaging and condiment squeeze bottles often contain Low-Density Polyethylene plastic because it is flexible and resistant to solvents. Low-Density Polyethylene plastic does not contain any known harmful chemicals. Low-density polyethylene containers may have the symbol "LDPE" on them.
Polyethylene teraphthalate is light-weight, clear and smooth; its manufacturers intend it for a single use only. While it does not contain bisphenol A or phthalates, it does contain antimony, a possible human carcinogen. Also, harmful bacteria can build up in it as you reuse it. Polyethylene teraphthalate containers may have the symbol "PET" on them.
Milk containers, detergent bottles, freezer bags and plastic grocery bags often contain high-density polyethylene, a relatively stiff plastic. High-Density Polyethylene plastic neither contains bisphenol A nor phthalates. It is not known to contain other harmful chemicals. High-density polyethylene containers may have the symbol "HDPE" on them.
You should avoid Polycarbonate plastic containers because they may contain bisphenol A that leaches into their contents. Type 7 plastics often have the symbol "PC" or "Other" on them. You will find polycarbonate plastics in 3- and 5-gallon water-cooler bottles; hard, plastic reusable water bottles; and to-go coffee mugs. Manufacturers use polycarbonate for these purposes because it is virtually shatter-proof.
Polyvinyl chloride contains phthalates that can cause reproductive problems in animals and humans. Polyvinyl Chloride plastic can be plasticized or unplasticized; the former is clear and flexible, the latter is more rigid. Food containers commonly made with polyvinyl chloride include fruit juice bottles, cooking oil bottles and clear food packaging. Plasticized PVC pipes and siding contain phthalates as well. Polyvinyl chloride containers may have the symbol "V" on them.
Polypropylene containers do not leach harmful chemicals into foods or liquids. They commonly contain yogurt, medicine, drinks, ketchup and medicines. Polypropylene plastic is flexible, hard and semi-transparent and has high resistance to solvents. Polypropylene containers may have the symbol "PP" on them.
When you choose plastic containers, you’d better consider what kind of things you want to place in the containers. Some of them are not safe for food.