The plastics most widely considered food grade are codes 1 (PET), 2 (HDPE), 4 (LDPE), and 5 (PP). These four types make up the vast majority of food packaging you see on store shelves, from water bottles and milk jugs to yogurt cups and squeeze bottles. But “food grade” isn’t simply about the type of plastic. It depends on how the plastic was manufactured, what additives were used, and what food it will touch.
What “Food Grade” Actually Means
A plastic is food grade when it has been evaluated for safety in direct contact with food. In the United States, the FDA requires manufacturers to demonstrate “a reasonable certainty of no harm” before a plastic can be used in food packaging. This isn’t a rubber stamp. The FDA analyzes testing data showing how much of the plastic’s chemical components migrate into food, estimates how much of those chemicals a person would consume over time, and compares that exposure to toxicological safety thresholds.
The FDA assumes a worst-case scenario in its calculations: that the material will capture 100 percent of the market for its intended use. This means the safety assessment accounts for a person encountering that plastic in every meal, not just occasionally. If the estimated dietary exposure falls below safe levels even under those conditions, the plastic gets cleared for food contact.
This is why the recycling number on the bottom of a container doesn’t automatically tell you whether it’s food safe. A code 5 container made for industrial chemical storage is not the same as a code 5 yogurt cup. The resin type is one factor, but the additives, colorants, and manufacturing process all matter.
The Seven Resin Codes, Ranked for Food Safety
Code 1: PET (Polyethylene Terephthalate)
PET is the clear, lightweight plastic used for soda bottles, cooking oil bottles, peanut butter jars, and microwavable food trays. It’s one of the most common food-contact plastics. However, PET is generally designed for single use. The bottles can deform when they reach about 70°C (158°F), and reusing them, particularly with liquids they weren’t designed for, can increase chemical migration. A water bottle should not be repurposed for vinegar or oil, for example, because acidity and fat accelerate the release of chemicals from the plastic. Cracks or interior damage also make PET bottles unsuitable for reuse.
Code 2: HDPE (High-Density Polyethylene)
HDPE is the sturdy, slightly opaque plastic used for milk jugs, juice containers, and cereal box liners. It’s one of the safest and most stable food-contact plastics, with low chemical migration even under normal use conditions. You’ll also find it in grocery bags and some reusable food storage containers.
Code 4: LDPE (Low-Density Polyethylene)
LDPE is the softer, more flexible cousin of HDPE. It shows up in bread bags, produce bags, squeezable condiment bottles, frozen food bags, and plastic food wrap. For most food storage, LDPE is considered safe. One caveat: LDPE food wrap in direct contact with fatty foods can allow higher migration of certain chemicals, so it’s worth avoiding prolonged contact between plastic wrap and high-fat items like cheese or meat, especially at warm temperatures.
Code 5: PP (Polypropylene)
Polypropylene is the workhorse of food-grade plastic. It’s used for yogurt cups, margarine tubs, ketchup bottles, drinking straws, deli containers, and take-out meal packaging. PP is heat-resistant compared to other food plastics, which is why it’s the most common material for microwave-safe containers. That said, even with PP, minimizing the heating of food in any plastic container reduces chemical exposure.
Code 3: PVC (Polyvinyl Chloride)
PVC is used in blister packs, clamshell packaging, and some shrink wraps. It’s one of the more concerning plastics for food contact because it contains phthalates, chemicals that make the plastic flexible. The FDA’s own review found phthalate content in PVC packaging ranging from 1% to 53%, and confirmed that some of those phthalates migrate into food. Research has linked phthalate exposure to hormonal disruption, fertility problems, and developmental issues in children. Most food safety experts recommend avoiding PVC for food storage whenever possible.
Code 6: PS (Polystyrene)
Polystyrene appears as foam cups, foam take-out containers, meat trays, and plastic tableware. The core concern is styrene, classified as a possible carcinogen. Research shows styrene leaches into food in proportion to storage time, and heating makes it worse. Food in polystyrene containers should not be microwaved unless the container is specifically labeled microwave safe. At room temperature and for short durations, PS is considered marginally safe, but it’s not a good choice for storing food long-term or reheating leftovers.
Code 7: Other or Mixed Plastics
Code 7 is a catch-all category that includes polycarbonate, bioplastics, and various blended materials. Some code 7 containers are used for food storage, including certain Tupperware products. The main concern here is BPA (bisphenol A), a chemical found in polycarbonate plastics. The FDA currently maintains that BPA is safe at the levels that migrate into food, based on a review of more than 300 studies completed in 2014. However, BPA-based polycarbonate is no longer authorized for baby bottles or sippy cups, a change that reflected the industry’s voluntary abandonment of that use rather than a formal safety ruling. Many consumers choose BPA-free products as a precaution, and containers labeled “BPA-Free” are now widely available.
What Makes Chemicals Leach Into Food
Even food-grade plastics release trace amounts of their chemical components into food. The question is how much, and five factors control that.
Temperature is the biggest driver. Migration increases as temperature rises and drops significantly at freezing temperatures. One study found migration increased dramatically at 68°C (154°F) after prolonged exposure, underscoring the risks of heating food in plastic or leaving plastic-wrapped food in hot environments like a car.
Fat content matters almost as much. Many plastic additives are fat-soluble, meaning they dissolve more readily into oily or fatty foods. Research comparing migration rates found that phthalates migrated at levels of 1% to 14% in edible oil but stayed below 0.35% in water. Chocolate, biscuits, meat, dairy, and cooking oils are all particularly prone to absorbing chemicals from their packaging.
Acidity also accelerates migration. Acidic foods like tomato sauce, citrus juice, and vinegar can pull chemicals from plastic more aggressively than neutral foods.
Contact time and surface area round out the list. The longer food sits in a plastic container, and the more surface area touches the food, the more migration occurs. This is why transferring leftovers to glass or ceramic for long-term storage is a practical way to reduce exposure.
How to Identify Food-Grade Containers
The recycling triangle with a number inside tells you the resin type but not whether that specific container was manufactured to food-grade standards. Look instead for a fork-and-glass symbol, which indicates the container is intended for food contact. There is no single universal “FDA-Approved” logo on consumer packaging, so this symbol, along with text like “food safe,” is typically what manufacturers use to communicate that the product meets food-contact requirements.
If you’re buying containers for food storage, prep, or meal planning, codes 2 (HDPE) and 5 (PP) are the safest general-purpose choices. For anything involving heat, PP is the better option. For cold storage, HDPE and LDPE both perform well. Glass and stainless steel remain the most inert options when you want to eliminate plastic migration entirely.
PFAS in Paper-Based Food Packaging
Food-grade concerns extend beyond plastic. Grease-proof coatings on paper food packaging, like fast-food wrappers and microwave popcorn bags, historically contained PFAS (per- and polyfluoroalkyl substances), a class of persistent chemicals linked to health concerns. In 2020, manufacturers voluntarily agreed to phase out PFAS-containing grease-proofing substances. By February 2024, the FDA confirmed that all such substances had been removed from the U.S. market, and as of January 2025, the authorizations for 35 PFAS-related food contact uses are no longer in effect. Some existing stock of older packaging may remain in circulation through June 2025.