Does San Pellegrino have microplastics?
Yes. We bought San Pellegrino at a grocery store in Los Angeles and it tested positive for particles consistent with microplastics, with a PET fluorescence signature.
So did the other six brands we tested. Not one came back clean. What follows is the reading, how it was produced, and — the part that matters most — what a fluorescent dye can and cannot prove.
San Pellegrino is the one glass bottle in the group, and glass does not shed PET. It still tested positive for a PET signature. We do not have an explanation we would stand behind — a lined cap, the bottling line, and our own laboratory background are all live possibilities, and this is exactly the kind of result a single screening round cannot resolve.
What the reading is — and isn’t
The number above is a fluorescence signal strength, not a particle count. It comes from staining the sample with undiluted Nile Red, pushing it through a PCTE membrane, and measuring how brightly the retained material glows across three wavelengths. A brand with a higher reading produced a stronger signal from material consistent with plastic. Nobody counted 143 of anything.
The scored brands span a narrow range, from Path at 106 to Dasani at 143. Three brands were not assigned a number in this round. We are not going to rank those three against each other to fill out a list, because we do not have the data to do it honestly.
Nile Red binds hydrophobic material. Plastic is hydrophobic — and so are lipids, oils, and some organic debris. That is why every result here is phrased as particles consistent with microplastics rather than as confirmed plastic. Definitive polymer identification requires spectroscopy, not a dye. Our full error budget, including the contamination sources we know about and the ones we suspect, is published at thewatertest.com/limitations. Read it before you treat any number on this page as gospel.
These are results from an ongoing study, not a peer-reviewed paper. Our method is adapted from published work (Meyers et al. 2022; Leonard et al. 2022); those authors have not reviewed or validated it.
The other six brands
San Pellegrino was one of seven bought together and run the same way. Reading any single brand in isolation is a mistake — the finding of the study is not that San Pellegrino is bad, it is that the container is the common thread and every brand tested positive.
Read the full comparison, including how we identified the plastic type and why the aluminum cans scored the same as the plastic bottles, in We Tested 7 Bottled Water Brands for Microplastics.
People also ask
+Does San Pellegrino have microplastics?
Yes. In our screening, San Pellegrino tested positive for particles consistent with microplastics under Nile Red staining, with a dominant PET fluorescence signature. Nile Red stains hydrophobic material rather than plastic specifically, so this is a screening result, not chemical confirmation.
+What kind of plastic was found in San Pellegrino?
The dominant fluorescence signature was PET — the plastic used in water bottles and can linings. The stain indicates material consistent with PET; definitive polymer identification requires spectroscopy, not a dye.
+Is San Pellegrino safe to drink?
No regulator has set a health-based limit for microplastics in drinking water, so a positive screening result is not a safety finding. San Pellegrino tested positive for particles consistent with microplastics, in the same range as the other six brands we bought — every one came back positive, whether it was bottled from purified tap, spring, or artesian water.
+Is San Pellegrino BPA-free?
The bottle itself is glass, which contains no BPA. San Pellegrino still tested positive for a PET fluorescence signature in our screening — the most likely sources are the cap liner or the bottling line, not the bottle. We did not test the cap material specifically.
+Does San Pellegrino have PFAS?
We don't know — this screening detects particles consistent with microplastics and nothing else, so it can't say anything about PFAS in San Pellegrino either way. PFAS is a different chemical class that needs its own lab test, and we didn't run one. Where we do have PFAS data is tap water: this site maps PFAS test results for US public water systems.
+Where does San Pellegrino's water come from?
Marketed as natural mineral water. Bottled in glass. That's the utility's/brand's own sourcing claim, not something we independently verified — our test measured what came out of the bottle, not where the water started.
+Which bottled water had the most microplastics?
By screening signal strength, Dasani read highest at 143 and Path lowest at 106 — a narrow band. Three brands (Fiji, Evian, San Pellegrino) tested positive but were not assigned a number this round, so we do not rank them against the rest. Every brand tested positive.
Test your own bottle
We ran San Pellegrino once, from one lot. The only way to know what a bottle in your fridge is shedding is to test it yourself. The same Nile Red screen we used here comes as an at-home kit — stain a 100 mL pour, filter it, and count the particles consistent with microplastics under the scope in about 15 minutes.
Test bottled water for microplastics at home →San Pellegrino is a registered trademark of its owner. The Water Map is not affiliated with, endorsed by, or sponsored by that company. The brand name is used here only to identify the specific product tested. We purchased the product at retail, at our own expense, and received nothing from anyone in connection with this test.
Every test we run is published, including the ones that make our own method look bad. All of our data is open — see the license.