Does Pyrex glass storage container have microplastics?

Food storage

Low exposure

Little or no plastic in contact with the contents. This is the option to switch toward.

Grade C60% confidenceGlass body with a polypropylene lid

0 · no plastic contact100 · constant contact

Two numbers, not one. Exposure is how much plastic contact this involves. Confidence is how much anyone has actually measured. How we score

The short answer

Barely. The glass body is inert whether it is cold, hot or acidic, and it is the correct answer for reheating. The lid is plastic — so reheat with the lid off, and the only remaining polymer contact is the seal touching the rim.

Glass bottle or jar format profile

Made ofGlass

Why Pyrex glass storage container scores 17

Glass food-contact surface, unaffected by heat, fat or acid
The lid is polypropylene with a silicone or polymer seal, and it sits above the food
Microwaving with the lid on puts that lid in the steam path — taking it off removes almost all of the remaining exposure
Glass does not craze or scratch into a shedding surface the way a plastic tub does

Where the 17 comes from

Five components, added. The page renders the parts rather than a stored total, so the number cannot disagree with the reasoning behind it.

Packaging contact: 5 / 30
Use conditions: 6 / 25
Measured release: 3 / 25
Polymer behaviour: 3 / 10
Processing: 0 / 10

Total exposure17 / 100

What we don't know

Container lids have not been measured. We score the body near the floor with confidence and the lid on reasoning. If you want a number for the lid, nobody has one.

This section is on every page in the database, including the ones where the answer is comfortable. How evidence grades work →

Better options

Ordered by how much they change, not by how much they cost.

Already the strongest option in this category

reheat with the lid off and it improves further

Stainless steel tins

if weight or breakage is the issue

Check the one in your kitchen

This page scores Pyrex glass storage container as a product. Formulations, packaging and suppliers change, and the specific item you own has its own condition — a scratched pan and a new one are not the same object. Scan yours for a score built from what is actually in front of you.

Scan my food storage

Sources behind this score

Each with the finding we use it for and the limitation that finding carries — because a study quoted without its boundaries is how this subject got so noisy.

peer-reviewed2023
Hussain 2023 (Nebraska) — Three minutes of microwaving released up to 4.22 million microplastic and 2.11 billion nanoplastic particles per square centimetre of container surface.
Limitation: Polypropylene and polyethylene containers with water and acetic acid, not real food. The headline figure is the worst case in the study, per cm², not per meal.
peer-reviewed2018
Schymanski 2018 — Compared formats head to head: single-use PET averaged 14 particles/L, returnable PET 118/L, glass bottles 50/L and beverage cartons 11/L.
Limitation: The glass result is the one people skip. Glass was not zero — particles came from the cap and the filling line, not the bottle wall. Small sample per format.

Frequently Asked Questions

Does Pyrex glass storage container have microplastics?

How was the Pyrex glass storage container score of 17 calculated?

Five components, added: packaging contact 5/30, use conditions 6/25, measured release 3/25, polymer behaviour 3/10 and processing 0/10. The page computes the total from those parts rather than storing it, so the number cannot drift from the reasoning.

Is Pyrex glass storage container safe?

The score does not answer that and we will not pretend it does. It measures plastic contact, which is a physical property of the product. Whether a given level of exposure affects health is an open question — the FDA states the current evidence does not demonstrate a risk at the levels found in food, while research such as the 2024 NEJM plaque study gives real reasons to keep studying it. Both are true at once.

Why is the confidence only 60%?

No measurement of the product or its category exists. The score rests on published evidence about how this polymer behaves under these conditions — heat, abrasion, contact time, fat content. Because this is not a direct measurement of the product itself, the score should be read as a well-reasoned estimate that could move if someone tests it.