Ongoing experiment — Round 1 of 3

We Tested 7 Bottled Water Brands for Microplastics. All 7 Had Them.

Liquid Death, Fiji, Crystal Geyser, Dasani, Evian, San Pellegrino, and Path — tested using Nile Red fluorescence microscopy in our LA lab. Every single one contained microplastic particles that matched PET (water bottle plastic).

Including the aluminum cans. More on that below.

The Experiment

We're testing the same 7 brands over 3 months under different storage conditions. Same methodology each time. Here's the plan:

1
Complete

March 2026

Fresh off the shelf, room temperature

2
Upcoming

April 2026

Same batch, 30 days at room temperature

3
Upcoming

May 2026

Same batch, 30 days in a hot car

The question everyone asks: does water get worse the longer it sits in plastic? We're going to find out.

Round 1 — March 2026

Fresh Off the Shelf

All 7 brands purchased from grocery stores in Los Angeles. Tested within 48 hours of purchase using our standard Nile Red fluorescence process.

Liquid Death

Aluminum can
Matched: PETSurprise

Aluminum cans have PET-based interior linings

Fiji

Plastic bottle
Matched: PET

Crystal Geyser

Plastic bottle
Matched: PET

Path

Aluminum can
Matched: PETSurprise

PET-lined aluminum can

San Pellegrino

Plastic bottle
Matched: PET

Evian

Plastic bottle
Matched: PET

Dasani

Plastic bottle
Matched: PET

The aluminum can finding

Liquid Death and Path both come in aluminum cans. Most people assume aluminum = no plastic. But aluminum cans have a thin plastic lining inside to prevent the metal from reacting with the liquid. That lining is made of PET-based plastic. Both brands matched our PET training signature — the classifier identified them as water bottle plastic without being told what container they came from.

All testing performed at our LA lab using peer-reviewed Nile Red fluorescence methodology. See how we test →

Next Up: Does Heat Make It Worse?

In Round 2, we're testing the same brands after sitting at room temperature for 30 days. In Round 3, we'll leave them in a hot car in an LA summer.

If you've ever left a water bottle in your car and drank it later — Round 3 is for you.

Results updated monthly. Check back in April for Round 2.

Curious What's In Your Tap Water?

We test tap water, filtered water, and bottled water for microplastics. $99, free shipping, results in 48 hours.

Peer-reviewed method|UCLA-validated|See the map →