Family use · $50 · two tests
Microplastic test kit for parents.
The published research on microplastics in baby bottles, breast milk, placenta, and infant stool is real and growing. The evidence on what it means for your kid's health is still being built. We sell tests, not panic. The microplastic test kit lets you measure the specific exposure in your house — the formula bottle, the filter pitcher, the reusable bottle in your kid's backpack — and decide what to do about it with a number in front of you instead of a Reddit thread.
What the published research actually says
Li, Shi, Boland — Nature Food, 2020
Polypropylene baby bottles release ~16.2 million microplastic particles per liter during WHO-guideline formula prep. Particle release scales with peak temperature and with shaking.
Ragusa et al. — Polymers, 2022
Microplastic particles detected in 75% of breast milk samples from healthy mothers. Most common polymers: PE, PVC, PP — the dominant consumer plastics.
Ragusa et al. — Environment International, 2021
First report of microplastics in human placenta. Detected in 4 of 6 placentas tested. Authors called for follow-up on prenatal exposure pathways.
Schwabl et al. — Annals of Internal Medicine, 2019
First detection of microplastics in human stool. All 8 study participants positive; multiple polymer types per sample. Suggests routine ingestion-to-excretion exposure in adults.
Mason, Welch, Neratko — Frontiers in Chemistry, 2018
Orb Media bottled-water survey. Microplastics found in 93% of bottled samples across 11 brands. Most common in PET-bottled water — including premium brands.
Orb Media / SUNY tap-water survey, 2017
Microplastic fibers found in 83% of tap samples globally, 94% of US samples. The most cited dataset on tap-water microplastic prevalence.
None of these papers asserted definitive health harm — every one explicitly called health impact an open question requiring follow-up research. The exposure numbers are well-documented; the dose-response data isn't. That's the honest state of the field as of 2026.
What to test, if you have kids in the house
Two tests per kit. Pick two of these — they're ordered by published-evidence weight, highest first.
- 1
Prepared formula from your usual bottle.
100 mL of cooled, prepared formula into the kit's cup. The peroxide step digests the milk fats. The Trinity College Dublin study used polypropylene bottles (most plastic bottles are polypropylene) and measured millions of particles per liter. Run the same protocol on your specific bottle.
Baby bottle guide → - 2
Your kid's reusable water bottle, after a 2–4 hour sit.
Fill it with the water you'd normally use, let it sit for a typical school-day duration, pour 100 mL into the kit. Compare to a control sample of the same water that didn't sit. The delta is what the bottle is shedding.
- 3
Cold tap water, kitchen, morning.
Your baseline. Tells you how much of any other reading is the water versus the container or filter.
Tap water guide → - 4
Your filter pitcher's output.
Brita, PUR, ZeroWater pitchers aren't NSF-certified for microplastic removal. Verify yours.
Filter testing guide → - 5
Bottled water you give your kids.
Particles in bottled water come mostly from the PET bottle itself, not the source. A bottle that lived in a hot car is the most particle-dense sample we've measured.
Bottled water guide →
What the kit will and won't tell you about your kid
It will tell you: how many plastic particles ≥1 µm are in the specific sample you ran. Whether that count is materially above a clean blank. How your bottle/filter/water compares to a reference. Whether switching containers actually changes the number.
It won't tell you: whether that count is “safe” for your specific child. Which polymer is in the particles (PE, PET, PP). What the long-term health impact is. Whether what you found caused any specific symptom. Those questions are open in the research literature; we aren't pretending to answer them.
What it does do is move the conversation from “the internet says microplastics are bad” to “my kid's formula bottle releases [N] particles per 100 mL, and switching to glass brings that to [much lower].” That's a different kind of decision.
FAQ
Are microplastics in baby formula a real concern, or is the internet exaggerating?
It's a documented concern with peer-reviewed evidence and an open question on health impact. The Trinity College Dublin study (Li, Shi, Boland — Nature Food, 2020) followed WHO sterilization guidelines for polypropylene baby bottles and measured an average of 16.2 million microplastic particles per liter released into formula during prep. That's the number the headlines come from. The authors did not assert health harm — they explicitly called that the next research question — but the exposure quantity is large and the particle counts replicable. Parents who switch to glass bottles do so on a precautionary basis; the kit lets you measure your own specific bottle.
Have microplastics been found in breast milk?
Yes. Italian researchers (Ragusa et al., 2022) detected microplastic particles in 75% of breast milk samples from healthy mothers. The polymers were the most common consumer plastics (polyethylene, PVC, polypropylene). The 2021 paper from the same group also reported microplastics in placenta. Neither study addressed health impact directly — both call for further research. We have a fuller writeup at /blog/microplastics-in-breast-milk.
What can I test with the kit if I have a young child?
Run the two tests on (a) prepared formula from your usual prep routine, with peroxide digest to handle the milk fats, and (b) a control sample of just the water you used. The comparison tells you how much of any particle load is from your bottle vs your water. You can also test breast milk, but the digestion step is harder and we don't recommend it as a first sample for non-lab users — the formula/water comparison is the cleanest A/B.
Should I switch to glass baby bottles?
That's a personal decision, and we sell tests, not advice. The published evidence shows polypropylene bottles release microplastic particles during normal formula prep at quantities orders of magnitude above ambient water. Glass and stainless steel don't. Whether to switch is your call — running the test on your specific bottle gives you a number to anchor that decision rather than an internet thread.
What about my kid's reusable water bottle for school?
Test it — that's literally what the second test in the kit is for. Fill the reusable bottle with the same water you'd put in it on a school day, let it sit for the typical sit time (2–4 hours), then pour 100 mL into the kit's viewing cup. Compare to a fresh 100 mL of the same water that didn't sit in the bottle. The delta is what the bottle is shedding into your kid's water over the course of a school day. Stainless steel and glass bottles usually return near-blank; some plastic and silicone bottles don't.
Is there any evidence microplastics in water are actually harming kids?
The honest answer in 2026 is: probable exposure is high, evidence of specific harm is suggestive but not conclusive, and the regulatory response is just beginning. The EPA added microplastics to Contaminant Candidate List 6 in April 2026. WHO's 2019 report concluded existing evidence didn't support an immediate health risk at typical drinking-water levels but explicitly called for more research. Animal studies show inflammatory and endocrine effects at high exposures. We're firmly in a 'precautionary action makes sense, panic doesn't' window — and the test gives you a count to act on rather than fear to react to.