Does Mountain Valley Spring Water (glass) have microplastics?
The short answer
Very little. Glass on the water-contact surface removes the bottle wall as a source, leaving the cap liner and the filling line — measured at roughly 50 particles per litre for glass generally, against hundreds of thousands for PET.
Glass bottle or jar format profile
Why Mountain Valley Spring Water (glass) scores 15
Glass bottle, still water, no carbonation pressure
Sold in returnable glass in some markets, which is the cleanest arrangement available at retail
Cap liner remains the one polymer contact point
Heavy glass means it is usually stored cool at home rather than in a car
Where the 15 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
- 3 / 30
- Use conditions
- 4 / 25
- Measured release
- 6 / 25
- Polymer behaviour
- 1 / 10
- Processing
- 1 / 10
What material touches the contents, over how much surface area, for how long. Glass and steel score near zero here; a film pressed against fatty food scores near the top.
Heat, abrasion, flexing, repeated opening, reuse beyond design life. The same bottle scores differently in a fridge and in a hot car.
What a laboratory actually counted, for this product or its category. A high number here means real particles were measured, not that the material looks suspicious.
How this specific polymer behaves — brittleness, fat solubility of its additives, thermal stability, whether it is a polymer named in existing restrictions.
What happened before you bought it. Retort sterilisation inside the pack, hot-filling, and pressurised brewing all happen at the most migration-favourable moment.
What we don't know
No brand-specific test. This is the glass category result applied to a glass bottle. The remaining unmeasured piece for every glass product is the same: what the cap liner and the bottling line contribute, which the one study that looked found was not zero.
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 among the cleanest formats
the returnable glass programme is better still
Filtered tap in a steel bottle
if you want to stop buying water at all
Check the one in your hand
This page scores Mountain Valley Spring Water (glass) 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 drinking waterSources 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-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.
- peer-reviewed2020
Sobhani 2020 — Simply tearing, cutting or twisting open plastic packaging generates microplastics at the opening — 10–30 nanograms per 300 cm of tear.
Limitation: Mass, not particle count, and it does not follow whether those particles land in the food. It is the reason cap and seal design belongs in an exposure score at all.