Which Plastic Bags Are Food Safe for Storing and Preserving Food?

December 25, 2025 •

4 min read

According to the Food and Drug Administration (FDA), plastic materials intended for food contact must be manufactured using virgin resins and meet strict safety standards to prevent contamination. Navigating the world of food storage means understanding which plastics are safe for direct contact with your food and how to identify the right bags for the job. Not all plastic bags are created equal, and using the wrong type can compromise the safety of your food, leading to potential health risks.

Quick Summary

This guide explains how to identify food-safe plastic bags, detailing the different types of approved plastics like LDPE, HDPE, and PP. It covers important safety symbols, materials to avoid, and safe practices for food storage, including proper reuse techniques and considerations for different temperatures.

Key Points

Food-Grade Certification: Only use plastic bags explicitly labeled as 'food grade' or bearing the wine glass and fork symbol, as they are tested and approved for direct food contact.
Identify Safe Plastics: Look for recycling codes #2 (HDPE), #4 (LDPE), and #5 (PP) on the packaging or bag, as these are typically considered food-safe.
Avoid Harmful Plastics: Steer clear of plastics with recycling codes #3 (PVC) and #6 (PS) for food storage, as they can leach harmful chemicals, especially when exposed to heat.
Check for Virgin Material: For industrial applications, ensure bags are made from virgin (new) resins, as recycled plastics require specific FDA review and may carry contaminants.
Mind the Temperature: Always follow manufacturer guidelines for temperature use; avoid microwaving or heating food in bags not explicitly rated as 'microwave safe' (typically PP).
Practice Safe Reuse: Reusing bags is only recommended for dry, non-greasy foods. Never reuse bags that held raw meat, eggs, or dairy, and always wash and fully air-dry them after use.

Understanding Food Grade Plastics

For a plastic bag to be considered food-safe, it must be made from materials that will not leach harmful chemicals or additives into food. These materials must be approved by regulatory bodies, such as the U.S. Food and Drug Administration (FDA), for direct food contact. The most common plastics used for this purpose are polyethylene and polypropylene, identifiable by their specific recycling codes.

Low-Density Polyethylene (LDPE)

LDPE is a flexible, soft, and transparent plastic widely used for food packaging. You'll find it in common items like bread bags, produce bags, and some squeeze bottles. Because of its flexibility and moisture resistance, LDPE is excellent for storing fresh produce, baked goods, and other items that require a good moisture barrier. However, it is not highly resistant to heat, so it should not be used for microwaving food. Look for the resin identification code '4' to identify LDPE bags.

High-Density Polyethylene (HDPE)

HDPE is more rigid and durable than LDPE, offering a higher strength-to-weight ratio. This makes it suitable for heavier or more irregularly shaped food items. Common uses include liners for bulk food containers, cereal box liners, and some reusable food buckets. HDPE also has good chemical and heat resistance. You can identify HDPE by the resin code '2'.

Polypropylene (PP)

Recognized by the resin code '5', polypropylene is known for its high heat tolerance. This makes PP bags and containers suitable for microwave use, as they can withstand high temperatures without leaching toxins. PP bags are also often clearer than PE bags and offer better barrier properties against moisture and vapor, extending the shelf life of the contents.

Polyethylene Terephthalate (PET or PETE)

PET is a strong, lightweight plastic commonly used for beverage bottles, but it is also used for some types of food packaging. PET bags are resistant to microorganisms and corrosion, making them a safe option. Look for the number '1' on the recycling symbol. However, bags made from this material are often intended for single use, especially when used for liquids, and should not be reused multiple times.

How to Identify Food-Safe Plastic Bags

Identifying food-safe plastic bags is crucial for protecting your health. Here are key indicators to look for:

The Wine Glass and Fork Symbol: This is the international icon for food-safe material and indicates that the product is approved for direct contact with food.
Manufacturer Labeling: Reputable brands will clearly state that their product is 'food grade' or 'safe for food contact'. Bags explicitly labeled for food storage (e.g., sandwich bags, freezer bags) are designed to be food safe.
Material Composition: Check the packaging for the plastic type or resin identification code. The safest codes for bags are typically 2 (HDPE), 4 (LDPE), and 5 (PP).
Visual and Olfactory Inspection: Avoid any bags that have a strong chemical smell, discoloration, or appear to be made from cheap, brittle plastic. Bags made from virgin plastics, which are required for FDA-approved food contact bags, should be odorless and clear.
Avoid Unknowns: Never use unmarked or unlabelled bags for food storage, as their safety cannot be verified.

Dangers of Using Non-Food-Safe Plastics

Using plastics not intended for food can pose significant health risks due to chemical leaching. Plastics like polyvinyl chloride (PVC), often marked with the recycling code '3', can contain plasticizers such as phthalates, which are known to be endocrine disruptors and can migrate into food. Polystyrene (PS), identified by code '6', is another plastic to avoid for food contact, especially with hot or oily foods, as it can release harmful substances. Furthermore, relying on recycled plastics for food storage can be risky unless the specific material has been vetted by regulatory bodies, as contaminants can compromise safety.

Important Considerations for Safe Usage

Even with certified food-safe bags, proper use is critical. While some bags can be reused after holding dry goods like bread or pretzels, never reuse a bag that has contained raw meat, poultry, fish, eggs, or dairy due to the high risk of lingering bacterial contamination. When washing and reusing bags for low-risk items, use warm (not hot) water and mild soap, and ensure they are completely air-dried. Heat can cause plastic to degrade and potentially leach chemicals. Use microwave-safe containers (often PP) for reheating and always let hot food cool before bagging it in PE bags.


Feature	HDPE Bags	LDPE Bags	PP Bags
Recycling Code	#2	#4	#5
Common Uses	Cereal box liners, bulk food liners, shopping bags	Bread bags, produce bags, frozen food bags	Microwave-safe food trays, snack pouches
Key Property	Strong, durable, more rigid	Flexible, soft, transparent	High heat tolerance, high clarity
Heat Resistance	Good; generally higher than LDPE	Poor; avoid heat	Excellent; microwave safe
Puncture Resistance	High	Low	High
Cost	Generally slightly lower	Low	Moderate
Moisture Barrier	Good	Good	Excellent

Conclusion

Choosing the right plastic bag for food storage is more than a matter of convenience; it is a fundamental aspect of food safety. By understanding the different types of food-grade plastics and learning to identify them through labels and recycling codes, consumers can make informed decisions. Always opt for bags specifically designated as food-safe, and pay close attention to material types and proper usage guidelines for temperature and reuse. Avoiding non-food-grade plastics like PVC and polystyrene is vital to prevent harmful chemical exposure. Sticking to food-safe plastics like LDPE, HDPE, and PP ensures your food remains fresh, uncontaminated, and safe for consumption. For additional details on specific FDA requirements, consumers can consult resources like those detailing FDA-Approved Plastics for Food Contact.

Frequently Asked Questions

To determine if a plastic bag is food-safe, look for a label stating 'food grade' or a symbol of a wine glass and fork. Also, check for the plastic's recycling code; numbers 2, 4, and 5 are generally safe for food contact.

High-density polyethylene (HDPE, #2), low-density polyethylene (LDPE, #4), and polypropylene (PP, #5) are among the safest plastics for food storage bags. HDPE is durable, LDPE is flexible, and PP offers high heat resistance.

Most major brands of resealable zipper-lock bags are made from food-safe LDPE plastic, which is approved for food contact. However, it is always best to confirm the 'food grade' label on the packaging.

It is safe to reuse bags that have stored dry, non-greasy foods, but they must be washed and completely air-dried between uses. Never reuse bags that contained raw meat, fish, eggs, or dairy due to bacterial contamination risks.

Unless a plastic bag is explicitly labeled 'microwave safe', you should not use it to heat food. Microwaving in non-compliant plastic can cause harmful chemicals to leach into your food.

Recycling codes, or resin identification codes, help indicate the type of plastic. For food safety, the key codes to look for are #2 (HDPE), #4 (LDPE), and #5 (PP).

BPA is not typically used to make the soft, flexible plastics used for food storage bags like LDPE. It is primarily found in hard polycarbonate plastics (often #7) and the lining of some food cans. Reputable brands often label their products as 'BPA-free'.