PET plastic bottle
High releasePolyethylene terephthalate, PET (#1)
The short answer
The single largest packaging source of microplastic exposure. Earth Action attributes roughly a third of all packaging-related exposure to PET bottles, and a 2024 PNAS study counted ~240,000 particles per litre in bottled water.
What actually drives release
- Particle shedding from the bottle wall into the contents over shelf life
- Cap abrasion each time the closure is twisted, which grinds the neck thread
- UV degradation, which Earth Action found can raise release up to 100x
- Mechanical stress from squeezing, dropping and pressure changes
When it gets worse
- Stored warm — a car, garage, sunny shelf or warehouse
- Opened and resealed repeatedly rather than drunk in one go
- Carbonated, since dissolved CO2 keeps the wall under constant pressure
- Refilled and reused, which it was never designed for
Better options
- Glass bottle
- Aluminium can
- Filtered tap water in stainless steel
Where you'll find it
Products scored in this format
Each carries its own exposure score, evidence grade and sources.
Aquafina
Lightweighted PET (#1) bottle with a polypropylene cap
Grade A · 88%
Evian
PET (#1) bottle with a polypropylene cap; a glass line also exists
Grade A · 87%
Nestlé Pure Life
PET (#1) bottle with a polypropylene cap
Grade A · 88%
Dasani
PET (#1) bottle with a polypropylene cap
Grade A · 88%
Fiji Water
PET (#1) bottle with a polypropylene cap
Grade B · 73%
Core Hydration
PET (#1) bottle with a polypropylene sport cap
Grade B · 71%
Smartwater
PET (#1) bottle with a polypropylene cap
Grade B · 72%
Poland Spring
PET (#1) bottle with a polypropylene cap
Grade B · 72%
Essentia
PET (#1) bottle with a polypropylene cap
Grade B · 72%
Bottled iced tea
PET (#1) bottle, hot-filled
Grade B · 72%
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Packaging changes the answer more than the brand does. Scan your product with MicroPlastics for a 0–100 exposure score and a lower-plastic version of the same thing.
Scan my productFrequently Asked Questions
Do pet bottles leach microplastics?
What makes pet plastic bottle worse?
What should I use instead of pet plastic bottle?
Sources
- Earth Action with rePurpose Global (2026). Microplastic migration from food and beverage packaging (reported May 2026). Forbes.
- Qian N, Gao X, Lang X, et al. (2024). Rapid single-particle chemical imaging of nanoplastics by SRS microscopy. Proceedings of the National Academy of Sciences (PNAS).
- Winkler A, Santo N, Ortenzi MA, et al. (2022). Does mechanical stress cause microplastic release from plastic water bottles?. Water Research.
- Hernandez LM, Xu EG, Larsson HCE, et al. (2019). Plastic teabags release billions of microparticles and nanoparticles into tea. Environmental Science & Technology.