LDPE Zip-Lock Plastic Bag (#4) vs. Styrofoam / Polystyrene Food Container

Materials

• Low-density polyethylene (LDPE, recycling #4)

Common claims

• BPA-free
• Leakproof zipper
• Freezer safe

Concerns / watch-outs

• Single-use at scale generates significant plastic waste
• LDPE can release additives when in contact with fatty or hot foods

Notes

LDPE is one of the safer single-use plastics, but the environmental footprint and single-use nature make reusable alternatives a better everyday choice.

Cleaner alternatives

• silicone storage bag
• stainless steel food container
• beeswax food wrap

Materials

• Expanded polystyrene (EPS, recycling #6)

Common claims

• Lightweight insulation
• Cost-effective packaging

Concerns / watch-outs

• Styrene — the building block of polystyrene — is classified as a possible human carcinogen (IARC Group 2B)
• Leaches styrene into fatty or hot foods
• Essentially non-recyclable and environmentally persistent

Notes

One of the worst food contact materials for both health and environmental impact. Avoid using for hot or fatty foods. Opt out whenever possible in favor of glass, stainless, or even HDPE.

Cleaner alternatives

• borosilicate glass container
• stainless steel food container
• paper lunch bag