LDPE Zip-Lock Plastic Bag (#4) vs. Pyrex Glass Food Storage Containers

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

• Tempered soda-lime glass
• Plastic or silicone lids

Common claims

• Oven, microwave, and dishwasher safe
• BPA-free lids
• Non-porous glass

Concerns / watch-outs

• Modern Pyrex sold in the US uses tempered soda-lime glass, not borosilicate — more susceptible to thermal shock than older versions
• Plastic lids may contain BPA; look for confirmed BPA-free lids or use silicone alternatives

Notes

Pyrex glass is one of the most recommended non-toxic food storage options. The glass body is completely inert. Replace plastic lids if they become scratched or stained.

Cleaner alternatives

• borosilicate glass container
• mason jar