If you’re looking to create plastic food packaging, it’s essential that you understand which plastics are food-safe. Food-safe plastic resins are those approved for contact with edibles by the Food and Drug Administration (FDA). They are known as food contact substances (FCS).
The FDA defines food contact substances as “any substance that is intended for use as a component of materials used in manufacturing, packing, packaging, transporting, or holding food.”
Here are the most common plastic resins approved by the FDA for food contact.
Polyethylene Terephthalate (PET)
PET resin is widely used in plastics that have food contact applications, from the ubiquitous 2-liter soda bottles to salad dressing bottles to peanut butter jars. The vast majority of single serving drinking bottles are made from PET. Specially-treated PET containers are microwaveable and used in take-out containers and single-serving food trays.
The FDA has approved both virgin and post-consumer recycled (PCR) PET for food contact. The resin has been thoroughly studied for negative health effects and found to cause none. According to a foundational study, “PET itself is biologically inert if ingested, is dermally safe during handling, and is not a hazard if inhaled.”
PET resin is stable. That means it doesn’t degrade when in contact with food or beverages, it resists corrosion, and it repels microorganisms. These qualities that make it ideal for food contact.
Polypropylene (PP)
Polypropylene is a widely used plastic. You likely have polypropylene plastic in your fridge and cupboards right now: it’s regularly used in reusable food storage containers. It’s also the resin used to make yogurt containers and other single-serving tubs.
PP plastics are approved for food contact. They are inert materials and do not present a health hazard to the consumers. The FDA began to approve recycled polypropylene as food-safe in 2013.
Polypropylene’s high melting point makes it suitable for microwaveable food containers. It’s nonvolatile and doesn’t react to liquids, acids, or bases, so it’s perfect to store a wide variety of foods.
High-Density Polyethylene (HDPE)
HDPE is the most common household plastic. At the grocery store, you see a lot of HDPE plastic bottles in the juice aisle and the milk case. HDPE is also used in butter containers, cereal box liners, and in large food buckets, such as those that supply school cafeterias and restaurants.
Virgin HDPE is a safe plastic for food contact. The FDA has sanctioned recycled HDPE for food contact on a case-by-case basis for over 20 years.
HDPE resin produces plastic that is corrosion-resistant and absorbs little moisture, making it well-suited for storing beverages. Also, HDPE containers don’t leach chemicals into their contents.
Low-Density Polyethylene (LDPE)
LDPE plastics are similar to HDPE plastics but are known for being less rigid. They are popular in squeeze bottles, such as used for ketchup and mustard; plastic films, such as those that wrap commercial baked goods and meat; and six-pack rings.
Virgin LDPE resins are safe for food contact. While recycled LDPE/PP blends have been approved for food contact by the FDA on two occasions, materials made from 100% PCR LDPE resin are not cleared for food contact.
LDPE has good chemical resistance, high impact strength, and strong wear absorption. Like PET and HDPE plastics, LDPE can hold your food products without leaching any harmful materials or allowing microorganisms to permeate.
Polycarbonate (PC)
Polycarbonate is commonly used in water-cooler bottles, baby bottles, and reusable water containers.
There’s been a lot of discussion the past few years about the food safety of polycarbonate because there is bisphenol A (BPA) in the resin). BPA is rumored to be hazardous to health. Because of the public scrutiny, it has been extensively tested. The average consumer intake of BPA is very low, and the chemical does not accumulate in the body. No health risks are known to exist at such small levels, and the FDA has concluded it is safe for food contact. Some manufacturers have substituted FDA-approved co-polyester to provide clear containers that are BPA-free.
PC is an especially tough plastic (it’s used for bullet-resistant windows), making it ideal for “unbreakable” water bottles and storing large amounts of a product.
There you have it — the most popular plastic resins approved for food contact. Interested in more info for your plastic packaging project? Check out our blog on the benefits of plastics packaging.