Before you spend the money
A consumer water test costs $598 and will not tell you what the plastic is. The lab’s own page says the most abundant particles are the hardest to detect. And the science behind testing human tissue is currently under formal challenge.
You can pay a laboratory to test your drinking water for microplastics. It costs about six hundred dollars. Before you do, it is worth knowing exactly what you get for that, because the labs themselves are refreshingly clear about it and almost nobody quotes them.
We are not a laboratory and we sell nothing. This is a reading of what the main consumer testing services say their own tests measure, in their own words, plus the state of the measurement science behind them. If you want the product side instead, our water filter page covers what the certifications actually certify.
Tap Score, one of the more established consumer labs, sells two. The standard microplastics water test is $598. The advanced version is $835. Both take about twelve business days.
Here is the scope, quoted from their own pages. The standard test offers “detection for the presence/absence of microplastics between 1-10 microns (μm) and quantification down to 10μm”. And, stated plainly: “Specific information about plastic type is not included in this test.”
So for $598 you learn whether particles between 1 and 10 microns are present, a count of particles above 10 microns, and nothing at all about what the plastic is. For $835 the advanced test adds polymer identification — polyethylene, polypropylene, PVC and polystyrene — but only for “particles 10μm and larger”.
That is Tap Score, on their own advanced test page, explaining a limitation. It is honest and it is the whole problem in one line: the particles that dominate by number are the ones the test is worst at seeing.
The same page notes that “particles greater than 10μm may not be identified by polymer if their smaller dimension is less than 10μm due to analytical limitations” — so a long thin fibre, which is one of the commonest shapes, can be counted without being identified.
The standard test page adds one more caution worth having: “Methods for microplastics analysis are rapidly improving and inter-lab comparisons can be difficult.” In other words, two labs testing the same water may not agree, and the lab says so before you buy.
If your interest is not your tap but your body — blood, tissue, “how much plastic is in me” — the measurement problem is considerably more serious, and it is currently a live dispute among the people who do the measuring.
The paper that drove most of the coverage is Nihart, Garcia, El Hayek et al. in Nature Medicine, February 2025, reporting microplastic concentrations in decedent human brain tissue and the widely repeated “spoonful of plastic” framing. Three things have happened to it since:
The technique at the centre of this, pyrolysis gas chromatography–mass spectrometry, burns the sample and identifies polymers from the breakdown products. It is a reasonable method with a real problem: biological tissue is full of organic molecules that break down into similar products. The original authors themselves recorded roughly a 25% coefficient of variation between laboratories.
None of this means there are no microplastics in human tissue. There probably are. It means that a number you are given for how much is in you is not currently a reliable number, and that anyone selling you a personal microplastics test is selling you a measurement the field is openly arguing about. We have gone through that evidence in full here.
There is a measurement in this area that works well, and it is worth knowing about because it gets confused with microplastics testing: total organic fluorine, measured by combustion ion chromatography. It burns a sample and measures all organic fluorine at once, rather than hunting for specific compounds one at a time.
A 2025 method paper in the Journal of AOAC International found that in the food-contact materials tested, “extractable organic fluorine constitutes less than 15% of the TOF” — that is, targeted testing for named PFAS misses more than 85% of the fluorine actually present. That is a real, reproducible, decision-changing measurement, and it is the one regulators have started writing into law. The explainer is here.
Our honest answer is no, and the reasoning is simple enough to check.
Ask what you would do differently on each result. If the test comes back positive, you would buy a filter. If it comes back negative — given a detection floor that misses the most abundant particle sizes, and a lab that tells you inter-lab comparison is difficult — would you genuinely conclude your water is clean and skip the filter? Almost nobody would.
If both answers lead to the same action, the test is not a decision tool. It is $598 spent on curiosity, and a good filter costs less than the cheaper test.
New scores, brands that finally answered, and any rule change that affects what you can buy. The list is not open yet — email us and we will add you when it is.