4 ms·
Avoiding and reducing microplastic false positives from dry glove contact
- schobi 5mo agoSummary: dry contact with nearly any laboratory glove will lead to sample contamination and over estimation of microplastics. They found one type of clean room gloves that contaminate less. Is there any indication on how bad this really is?
- martiuk 5mo agoAround 2000 to over 7000 false positives per mm^2 based on the type of glove. Essentially, regular lab gloves shed enough particles to swamp microplastic measurements to warrant switching to clean room gloves for this type of analysis.
- ginko 5mo agoShouldn't any lab analysis have control samples to detect environment contamination like this?
- AlpinMouton 5mo agoIt's difficult to avoid contamination, since everything (samples, containers, equipements, etc) will have been in contact with glove at least once, and good decontamination is very hard.
- nom 5mo agoYes, exactly, that's why you use control samples to get the baseline.
- DangitBobby 5mo agoYou see how it's a bit of a self-starting problem?
- ginko 5mo agoLet's say you want to determine the amount of microplastics in ocean water samples. You'd create a control by creating saline solution with distilled water and sodium chloride. Then you treat both the control and your sample(s) the same way in the analysis. Surely something should tick you off when the microplastic levels aren't much lower in your control compared to your actual sample?
- DangitBobby 5mo agoThey are handling both the control and the sample with gloves. Which is the same way. They are contaminating both. It's useless to argue about how contamination could have theoretically been avoided in an alternate past in hindisght. You don't realize there's a potential contaminant until you do and then you mitigate it. I'm sure they are smart enough now that they realize they are systematically introducing contaminants, they will be able to figure out how to control for it.
- ginko 5mo ago>They are handling both the control and the sample with gloves. Which is the same way. They are contaminating both. That's the point. If the control also gets contaminated then they should get >0 results in the control (when basically zero was expected) and that should have raised awareness of this problem pretty much immediately.
- mrob 5mo agoFreshly cleaved mica has an extremely clean and flat surface.
- reedf1 5mo agoThere is growing evidence that there is much less to worry about on microplastics on several fronts. 1. A whole cohort of core studies have been judged to have invalid methodology due to not recording baseline microplastic levels (https://www.pnas.org/doi/10.1073/pnas.2411099121 https://www.pnas.org/doi/10.1073/pnas.2411099121) 2. Young-onset cancers (especially colorectal cancer) which were inferred to be caused by a rise in microplastics are being linked explicitly to other mechanisms and cohorts. (https://ascopubs.org/doi/10.1200/JCO.2025.43.16_suppl.3619 https://ascopubs.org/doi/10.1200/JCO.2025.43.16_suppl.3619)
- kuerbel 5mo agoI think those papers mostly show that parts of the microplastics literature were overstated or methodologically weak, not that microplastics are harmless. The PNAS paper is a pretty good critique of contamination/baseline issues, and I agree some of the “microplastics are causing young-onset cancer” claims got ahead of the evidence. But the broader concern still exists: people are clearly exposed constantly, particles are being found in human tissue, and there are plausible mechanisms for harm. So no, there is not "much less to worry".
- reedf1 5mo agoI agree that there is not evidence to "not worry", but many explicit worries are being accounted for. Also - in terms of human tissue: "The problem is that some small molecules in the fumes derived from polyethylene and PVC can also be produced from fats in human tissue. Human samples are “digested” with chemicals to remove tissue before analysis, but if some remains the result can be false positives for MNPs. Rauert’s paper lists 18 studies that did not include consideration of the risk of such false positives." (https://www.theguardian.com/environment/2026/jan/13/microplastics-human-body-doubt https://www.theguardian.com/environment/2026/jan/13/micropla...) and Rauert's paper (https://pubs.acs.org/doi/10.1021/acs.est.4c12599 https://pubs.acs.org/doi/10.1021/acs.est.4c12599)
- card_zero 5mo ago"Exercise induced gastrointestinal injury"!
- feverzsj 5mo agoNow, I'm worried about people preparing my food with gloves.
- janderson215 5mo ago“Are you wearing gloves? That’s disgusting. Use your bare hands, you animal.”
- elgertam 5mo ago"I only allow robots with stainless steel tools to prepare and serve my food."
- teddyh 5mo ago“He wants metal; they always do.” — Segregationist, Isaac Asimov, 1967: <https://archive.org/details/Fantasy_Science_Fiction_v035n04_1968-10_PDF/Fantasy__Science_Fiction_v035n04_1968-10_PDF?view=theater#page/n77/mode/2up https://archive.org/details/Fantasy_Science_Fiction_v035n04_...>
- Saline9515 5mo agoActually bare hands ok while working in food production if correctly washed with an antimicrobial agent, and assuming one doesn't pick his nose on the job.
- akramachamarei 5mo agoPicking noses presumably isn't a unique problem to bare hand prep, unless the ungloved finger is somehow a more tempting scoop?
- tekla 5mo agoI find that picking your nose can be a unconscious thing you do, but the sensation of sticking a glove into your nose quickly makes it very not unconscious very fast But of course, hopefully the person in question will choose to change the glove. Otherwise yes, glove wearing dogma is overdone, however still, should probably wear them.
- giantg2 5mo agoThis shouldn't really be a problem. Just use aseptic techniques to avoid glove contact (direct, indirect, and airborne) with the test material.
- procaryote 5mo agoI feel the field of microplastics has done itself no favours by referring to everything < 5mm as a microplastic particle. 5mm is huge. In american terms, it's amost as wide as a .22 calibre bullet, or a popcorn kernel