Nitrile and latex gloves may cause overestimation of microplastics
news.umich.edu
news.umich.edu
The reason I bring this up is because the researchers had taken the essential precaution of providing me with a ceramic knife to do the cutting (and platic pliers), to eliminate the risk of contaminating the samples with metal from ordinary cutting implements.
That some research on microplatics did not take into account the absolutely mental amount of single-use plastic that is involved in biological research, particularly gloves of all things, boggles the mind.
Agreed. While I didn’t anticipate this myself, nor would have likely figured it out myself, I also don’t expect my claims to influence global policy.
The scientists who failed to realize this do expect that, so the standards we expect from them need to be higher in accordance with that.
This was taken into account: https://news.ycombinator.com/item?id=47563392
"I have unique insight as a non-expert that all experts miss and the entire field is blind to" -> usually nonsense
"I think in this specific instance academically qualified people are missing something that's obvious to me" -> often true.
"Nanomolar" is a dissolved-species concentration unit. It doesn't apply to spectroscopic particle counting.
Been here 16 years, it's always an adventure seeing whether stuff like this falls into:
A) Polite interest that doesn't turn into self-keyword-association
B) Science journalism bad
C) Can you believe no one else knows what they're doing.
(A) almost never happens, has to avoid being top 10 on front page and/or be early morning/late night for North America and Europe. (i.e. most of the audience)
(B) is reserved for physics and math.
(C) is default leftover.
Weekends are horrible because you'll get a "harshin' the vibe" penalty if you push back at all. People will pick at your link but not the main one and treat you like you're argumentative. (i.e. 'you're taking things too seriously' but a thoughtful person's version)
I used to be a code monkey, I wrote systems software at megacorps, and still can't understand why so many programmers irresponsibly write memory unsafe code given it has a global impact.
So Poe's law applies here.
(to go a bit further, in case it's confusing: both you and I agree on "why do people opt-in to memunsafe code in 2026? There’s no reason to" - yet, we also understand why Linux/Android/Windows/macOS/ffmpeg/ls aren't 100% $INSERT_MEM_SAFE_LANGUAGE yet, and in fact, most new written for them is memunsafe)
Creating a user interface for the world’s knowledge doesn’t make the developer an expert on the knowledge that the interface holds in its database. Regardless of how sophisticated that interface might be.
Being certain, on the other hand, requires an assumption that you are a subject expert.
But this is all moot anyway because you’re constructing an elaborate strawman here. The original point was that the GP (possibly you?) trusts SWE more than others because they built AI. And I said building databases doesn’t make you smart at the subject loaded into the database.
Really, this whole premise of SWEs assuming expertise on subjects they’ve trained AI on says more about the Dunning-Kruger effect than anything of value in our little tangent.
Typically when I get genuine responses to the question, "What would change your mind?" it's an incredibly high bar that is practically impossible to achieve. That's not necessarily a bad thing, but when skepticism is applied without deliberation, it supports biases rather than truth.
So yes, you do need to be qualified to be skeptical, SWEs doubly so.
There is practically universal recognition among microplastics researchers that contamination is possible and that strong quality controls are needed, and to be transparent and reproducible, they have a habit of documenting their methodology. Many papers and discussions suggest avoiding all plastics as part of the methodology, e.g. “Do’s and don’ts of microplastic research: a comprehensive guide” https://www.oaepublish.com/articles/wecn.2023.61
Another thing to consider is that papers generally compare against baseline/control samples, and overestimating microplastics in baseline samples may lead to a lower ratio of reported microplastics in the test samples, not higher.
When you are taking measurements at the detection limit of any molecule that is widespread in the environment, you are going to have a difficult time of distinguishing signal from background. This requires sampling and replication and rigorous application of statistical inference.
> Another thing to consider is that papers generally compare against baseline/control samples,
Right, that’s what a control is.
> and overestimating microplastics in baseline samples may lead to a lower ratio of reported microplastics in the test samples, not higher.
There’s no such thing as “overestimating in baseline samples”, unless you’re just doing a different measurement entirely.
What you’re trying to say is that if there’s a chemical everywhere, the prevalence makes it harder to claim that small measurement differences in the “treatment” arm are significant. This is a feature, not a bug.
> There’s no such thing as “overestimating in baseline samples”
What do you mean? Contamination and mis-measurement of control samples is a thing that actually happens all the time, and invalidates experiments when discovered.
> What you’re trying to say is that if there’s a chemical everywhere, the prevalence makes it harder to claim that small measurement differences in the “treatment” arm are significant.
No. What I was trying to say is that if the control is either mis-measured, for example by accidentally counting stearates as microplastics, or contaminated, then the summary outcome may underestimate or understate the prevalence of microplastics in the test sample, even though the measurement over-estimated it.
The entire point of a control is to test for that sort of contamination (or more generally, for malfunctions in the experimental workflow). In the case of a negative control, specifically, you're looking for an "positive" where one should not exist. If an experiment is set up such that you can obtain differential contamination in the controls but not the experimental arms, as you've described, then the entire experiment is invalid.
> What I was trying to say is that if the control is either mis-measured, for example by accidentally counting stearates as microplastics, or contaminated, then the summary outcome may underestimate or understate the prevalence of microplastics in the test sample, even though the measurement over-estimated it.
The control cannot be "mis-measured", any more or less than the other arms can be "mis-measured". You treat them identically, otherwise the control is not a control. Neither example you've given are exceptions: if the assay mistakes chemical B for chemical A, then it will also do so for the non-controls. If the experimental process contaminates the controls, it will also contaminate the non-controls.
What you're missing is that there's no absolute "correct" measurement -- yes, the control may itself be contaminated with something you don't even know about, thus "understating" the absolute measurement of whatever thing you're looking for, but the absolute measurement was never the goal. You're looking for between-group differences, nothing more.
Just to make it clearer, if I were going to run an extremely naïve experiment of this sort (i.e. detection of trace chemical contamination C via super-sensitive assay A) with any hope of validity, I'd want to do multiple replications of a dilution series, each with independent negative and positive controls. I'd then use something like ANOVA to look for significant deviations across the group means. This is like the "science 101" version of the experimental design. Any failure of any control means the experiment goes in the trash. Any "significant" result that doesn't follow the expected dilution series patterns, again, goes in the trash.
(This is, of course, after doing everything you can to mitigate for baseline levels of the contaminant in the lab environment, which is a process that itself probably requires multiple failed iterations of the experiment I just described.)
Most of the plastic contamination papers I have read are far, far from even that naïve baseline.
No, the point of a control is to give you a reference point that shares all the systemic biases and unknown unknowns, not to detect those biases. If you follow the same procedure on a known null and on your experiment and observe an effect, assuming you really did exactly the same thing except the studied intervention, you can subtract out the bias.
This one example of technical jargon diverging from colloquial or intuitive use, and it is the type of thing people who haven't had statistics or scientific process education often struggle with because they keep applying their colloquial intuitions.
You talk like you understand this on the rest of the comment so I'm confused by this framing, and the person you are replying to points out (in my reading ) that contamination of the control 1) does happen in practice (in the sense that there was an accidental intervention) and 2) if the gloves contaminated both the measurements and control the same way then the control is exactly serving it's purposes
> then the entire experiment is invalid
Isn’t that what I said? You even quoted me saying it. But I didn’t say anything about only control being contaminated or mis-measured, I think you’re assuming something I didn’t say. Validity is, of course, compromised if the control is compromised, regardless of what happens to the test samples.
> The control cannot be “mis-measured” […] yes, the control may itself be contaminated […]
So which is it? Isn’t the article we’re commenting on talking about the possibility of mis-measuring? Are you suggesting this article cannot possibly be an issue when measuring control samples? Why not?
Controls absolutely can be mis-measured or contaminated or both. It has been known to happen. It’s bad when this happens because it means the experiment has to be re-done.
> If the experimental process contaminates the controls, it will also contaminate the non-controls
Yes! This is exactly what I was implying, and is exactly how you might end up underestimating the relative presence of whatever you’re looking for in the test, if your classification procedure overestimates it.
> You’re looking for between-group differences
Yes! and this is why if, for example, you didn’t notice your control had stearates and you counted them as microplastics accidentally, and then reported that your test sample had 2x more microplastics than your control, you might have missed the fact that your test actually had 10x more microplastics, or that your control actually had none when you thought incorrectly that it had some.
This, of course, is not the only possible outcome, not the only way that the results might be distorted. But this is one possible outcome that the Michigan paper at hand is warning against, no?
> Most of the papers I have read are far, far from even that naïve baseline.
Short of it, or exceeding it? Based on earlier comments, I assume you mean they’re not meeting your standards. I don’t know what you’ve read, and my brief googling did not seem to support your claims here so far. Can you provide some references? It would be especially helpful if you showed recent/modern SOTA papers, work that is considered accurate, and is highly referenced.
> "You found a paper"
johnbarron didn't find it. The authors cited it as foundational to their own work. it's ref. 38 in the paper under discussion. From the paper: "this finding had not been reported in the MP literature until 2020, when Witzig et al. reported that laboratory gloves submerged in water leached residues that were misidentified as polyethylene."[1]
> "most of these plastic studies are [not] doing the necessary controls"
which studies? The paper they linked surveys 26 QA/QC review articles[1]. Seems well understood.
> "a laboratory setting where nanomolar detection levels are used to make broad claims"
This is like saying "miles per gallon" when discussing weight. "nanomolar detection levels"...microplastics are individual particles identified by spectroscopy, reported as particles per mm^2. "Nanomolar" is a dissolved-species concentration unit. It has nothing to do with particle counting. (I, and other laymen, understand what you mean but you go on later in the thread to justify your unsourced and unjustified claims here via your subject-matter expertise.)
> "(almost impossible) task of preventing the contamination"
The paper provides open-access spectral libraries and conformal prediction workflows to identify and subtract stearate false positives from existing datasets[1]. Prevention isn't the strategy. Correction is. That's the entire point of the paper they linked and the follow-up in [2]
[1] https://pubs.rsc.org/en/content/articlehtml/2026/ay/d5ay0180...
[2] https://news.umich.edu/nitrile-and-latex-gloves-may-cause-ov...
This paper used “light-based spectroscopy” [1]. Many others use methods that depend on gas chromatography or NMR. A relatively infamous recent example used pyrolysis GCMS to make low-concentration measurements (hence: nanomolar), which they credulously scaled up by some huge factor, and then made idiotic claims about plastic spoons in brains.
Relatively little quantitative science in this area depends on counting plastic particles in microscopic images, but it’s what gets headlines, because laypeople understand pictures.
[1] as an aside, the choice of terminology here is noteworthy. A simple visual light absorption spectra is also “light based spectroscopy”, but is measuring the aggregate response of a sample of a heterogeneous mixture, and is conventionally converted to molar equivalents via some sort of calibration curve (otherwise you can’t conclude anything). But there could be other approaches that are closer to microscopy, which they also discuss. “Particles per square millimeter” is also a unit of concentration (albeit a shitty one, unless your particles are of uniform mass).
Anyway, the point is that these kinds of quantitative analyses are all trying to do measurements that are fundamentally about concentration, which is why I chose the words that I did.
"1 nanomole of polyethylene" requires you to pick an arbitrary average molecular weight.
This changes the answer by orders of magnitude depending on what you pick.
Which is why nobody does it.
> Relatively little quantitative science in this area depends on counting plastic particles in microscopic images...Many others use methods that depend on gas chromatography or NMR.
So we're dismissive of some subset of papers, because they get false positives using toy methods.
Real science would use gas chromatography.
But...the paper we're dismissing tested gas chromatography. And found the same false positive. [1, in abstract]
> A relatively infamous recent example used pyrolysis GCMS to make low-concentration measurements (hence: nanomolar)
The brain study I'm guessing you are referring to, [2], measured low concentrations, yes.
But it reported them in ug/g.
Because polymers don't have a defined molecular weight.
> made idiotic claims about plastic spoons in brains
The brain study I'm guessing you are referring to, [2], does not mention spoons, or, come close.
Are we sure there's a paper that did that?
[1] Witzig et al, https://pubs.acs.org/doi/10.1021/acs.est.0c03742, "Therefore, u-Raman, u-FTIR, and pyr-GC/MS were further tested for their capability to distinguish among PE, sodium dodecyl sulfate, and stearates. It became clear that stearates and sodium dodecyl sulfates can cause substantial overestimation of PE."
[2] Campen et al, https://pubmed.ncbi.nlm.nih.gov/38765967/, "Bioaccumulation of Microplastics in Decedent Human Brains"
That was never my argument. Read it again.
What boggles the mind is you commenting on an article you clearly did not read...stating something that is not there...
"Nitrile and latex gloves that scientists wear while they are measuring microplastics may lead to a potential overestimation of the tiny pollutants, according to a University of Michigan study."
The samples were not contaminated by plastic in the gloves. Latex gloves don't contain plastic, they're made from natural rubber. Nitrile gloves also don't contain plastic, although they're very similar to plastic.
The contamination that this study found wasn't microplastic contamination. The gloves weren't adding microplastics. The gloves were adding stearates, which aren't plastic, but look like microplastic in many of the methods for measuring microplastics.
There is a “case files” podcast on it that I found quite good.
https://casefilepodcast.com/case-178-the-woman-without-a-fac...
At worst, I'd expect to see people disregarding the threat, not disregarding the presence of the microplastics themselves.
On the other hand I suspect much of the real science on environmental plastic might avoid the term microplastic since it seems to have a meaning that flows to whatever can make the scariest headline today. I have seen the size range to qualify run from microscopic up to a couple of millimetres. Volumes, quantities, or location stated without regard to individual particle size. I'm relatively certain that they have not discovered 1mm particles inside red blood cells.
Even what counts as a plastic seems to be an easy way of adding vagueness, I saw one table that seemed to count cellulose as a plastic, which makes sense if you are thinking about properties of the material, but unsurprisingly easy to come across that it's not really worth going looking for it.
The only connection between the crimes was the presence of DNA from a single female, which had been recovered from 40 crime scenes, ranging from murders to burglaries. In late March 2009, investigators concluded that there was no "phantom criminal", and the DNA had already been present on the cotton swabs used for collecting DNA samples; it belonged to a woman who worked at the factory where they were made.
The Bay Harbor Butcheress[0] :)
[0]: https://en.wiktionary.org/wiki/butcheress (at First I made it as a joke but turns out that butcheress is a real term, indeed)
This type of research requires very little creativity or study design -- just throw a dart in a room and try and find microplastics in whatever it lands on. Boom, you get a grant for your study, and journalists will cover your result because it gets clicks. Whenever this type of incentive exists, we should be very skeptical of a rapidly-emerging consensus.
If it's true that microplastics are everywhere and in everything (which maybe that's now not actually the case), even a very small chance that there's some serious harm we're not aware of should be taken extremely seriously, because at this point there's (apparently) no practical way to avoid or get away from them, or to even stop producing them. And since they're such a new phenomenon in these quantities, we haven't really had the time to really drill down and figure out *if* there are longterm negative effects.
IMO, we should be intellectually humble about our lack of knowledge on these microplastics, and part of that humility should involve being cautious about introducing them to our bodies and environment.
https://www.ehn.org/toxic-tire-chemicals-threaten-salmon-as-...
What does that look like today, pragmatically speaking?
For example, using a reusable metal gourd instead of plastic water bottles for the task of 'portable hydration'.
and because this is Hacker News, I'll kindly welcome the comment: 'well actually metal gourds have some toxic substance in the lining that's worse than microplastics' and reply: ok, Cardboard bottles then. Or a gourd made of a sheep's bladder like back in the good ol' days, whatever they used back in the bronze age.
Not that it really matters, climate driven ecological collapse will probably make it irrelevant by the time it would matter
Just because you as a single consumer may not seem impacted by microplastics does not mean it's alarmism to suggest that it's a really bad phenomenon.
>This type of research requires very little creativity or study design -- just throw a dart in a room and try and find microplastics in whatever it lands on. Boom, you get a grant for your study
Precisely, and mapping of that kind is entirely valid and required in huge amounts to have the full picture. Somebody has to do the grunt work.
Hey remember what happened with BPA? That was frustrating. We saw ostensibly legitimate concern, then manufacturers telling us they got rid of it. Maybe it would’ve inspired confidence if the removal adverts came with data sheets on the replacement chemicals.
Just like BPA, BPS is an endocrine disruptor. The idea that it's less harmful than BPA is mostly due to lack of research.
No way this isn't heavily studies by now.
Edit: found a whole meta-study in like 30 seconds of searching: https://www.frontiersin.org/journals/public-health/articles/...
> Micro/nano-plastics negatively affected the blood glucose metabolism, lipid metabolism, and reproductive function in mice.
What great pains are they going through? The study is a discussion of measurement techniques and makes no comment on whether they are harmful because that’s irrelevant to the paper.
This could just as easily be a paper on how wearing the wrong type of gloves results in overestimating calcium in soil. You’re the one injecting a political agenda.
https://www.youtube.com/shorts/-x6TKr35J9I
No affiliation, just thought this was extremely interesting. This seems to boil down entirely to nutrition, from what I gathered.
The below meta-study largely discusses sampling methods and protection from cross contamination so everyone here acting like this one study’s somehow invalidates decades of quality research:
>Due to the wide contamination of the environment with microplastics, including air [29], measures should be taken during sampling to reduce the contamination with these particles and fibers. The five rules to reduce cross-contamination of microplastic samples are: (1) using glass and metal equipment instead of plastics, which can introduce contamination; (2) avoiding the use of synthetic textiles during sampling or sample handling, preferring the use of 100% cotton lab coat; (3) cleaning the surfaces with 70% ethanol and paper towels, washing the equipment with acid followed by ultrapure water, using consumables directly from packaging and filtering all working solutions; (4) using open petri dishes, procedural blanks and replicates to control for airborne contamination; (5) keeping samples covered as much as possible and handling them in clean rooms with controlled air circulation, limited access (e.g. doors and windows closed) and limited circulation, preferentially in a fume hood or algae-culturing unit, or by covering the equipment during handling [15], [26], [95], [105], [107]. A fume hood can reduce 50% of the contamination [105] while covering samples during filtration, digestion and visual identification can reduce more than 90% of contamination [95].
So don’t ghost ride the whip about the death of the microplastic plague just yet.
https://www.sciencedirect.com/science/article/pii/S016599361...
“ Stearates are salts, or soap-like particles. Manufacturers coat disposable gloves with stearates to make them easier to peel from the molds used to form them. But stearates are also chemically very similar to some microplastics, according to the researchers, and can lead to false positives when researchers are looking for microplastic pollution.”
Stearates aren’t microplastics. Maybe we need to be concerned with stearate pollution too.
I mean, I get the instinct that foreign-entity can't exactly be good for me, but the same instinct applied to GMOs, and as far as I know organic foods have never yielded any sort of statistically visible health impacts.
Plastics earn their keep in general by being non-reactive and 'durable', so it's not entirely shocking if they can pass through (or hang around inside) the body without engaging in a lot of biochemical activity.
I have seen zero evidence that they are bad in very small quantities, but the dose can make the poison and they are out there in increasingly alarming quantities.
I'd also consider plastic, and their additives, to be a lot bigger and longer lasting unknown than GMOs.
Plastics are chemical "sponges" that will soak up pollutants over time from the environment (brominated fire retardants, bisphenols, PBCs, pesticides, phthalates, heavy metals, etc) and deliver them in a concentrated dose into the body.
https://www.sciencedirect.com/science/article/pii/S030438942...
https://www.researchgate.net/profile/Verla-Wirnkor-2/publica...
We’ve reached the absurd point where all sides of the political spectrum have sacred cows, and an exceedingly poor understanding of scientific reasoning, and all sides also try to dunk on the others by claiming scientific authority.
More like flippancy, even hubris.
The approach you advocate is essentially the EU's precautionary principle. [1]
[1] https://eur-lex.europa.eu/EN/legal-content/summary/the-preca...
Even if plastics of all sizes are 100% biologically inert, they're still a Trojan Horse for other toxins.
https://www.sciencedirect.com/science/article/pii/S030438942...
https://www.researchgate.net/profile/Verla-Wirnkor-2/publica...
Roughly 50% of indoor dust is composed of microplastics, so it's not like it's uncommon.
I highly doubt that. Soil, skin and pollen are usually the big ones. Hairs depending one how you count dust, but eliminating hair like fibres would also eliminate most of the sources of plastic, unless you allow really large particle sizes.
[edit] Checking research. The highest claim I found was 39% of fibres (in household dust, Japan). but that seemed to be per particle not by volume.
>eliminating hair like fibres would also eliminate most of the sources of plastic
If you allow fibres they'd be 0.01% of fibres if you've got a dog anything like mine.
It was just an aside anyway. My main point is that MPs are vehicles for toxins, which addresses the original question about how (supposedly inert) microplastics can cause harm.
Thanks again for setting me straight, I must have misremembered.
I like this study https://link.springer.com/article/10.1186/s12302-019-0279-9 not so much because they give a definitive answer, but the provide a much better sense of the nuance that bold claims miss. It's too easy to make a bold claim of a number that seemingly contradicts another similarly bold claim. The nuanced approach can often reveal that both bold claims are, in fact, true but not meaningful because they lose significant context.
For example, a lot of reports on water use neglect locality of the use. What the term 'use' means (how much water does a hydroelectric dam use, is that the same sense of use as irrigation?), is there scarcity where it is used? Is it the same class of water as the water in demand (potable / brine / etc.)
The haphazard use of terms has resulted in an insane range of claims of water use per AI query (or lithium mined, or tomatoes grown). The lack of faith leads people to assume one party is lying, but often all of the numbers are accurate in a kind of way. Just not comparable and sometimes not even meaningful
Synthetic textiles (clothes, upholstery, carpet, dryer exhaust, washer drainage) are of course the biggest culprits, with most of that trapped indoors with us, or co-located with human activity. If you have a dog that may change the mass fraction, but the MP exposure remains the same (or worse due to additional wear).
Road and tire wear is the other big contributor, again co-localized with population density. That's one of those nuanced cases, because a large fraction of the tire mass is actually natural rubber. The synthetic additives make it categorized as 100% plastic, but this may not accurately reflect reality in terms of the chemistry or hazard-based analysis.
One of the sources of intentionally manufactured microplastics are known as porous polymers in fine mesh sizes.
This is over a $1 billion market and growing.
One of the pharmaceutical uses is precisely as a medium to deliver oral medications in a time-release way.
https://www.linkedin.com/pulse/porouspolymer-bead-real-world...
These porous polymer powders consist entirely of microscopic little sponges where they soak up and/or leach out all kinds of chemicals more so than the plain polymer, and with different affinity too.
However, even when common waste plastic particles themselves are not microscopically porous, different plastics soak up different chemicals to different degrees depending on what type of contact they come into. For instance kilos of polyethylene nurdles floating in the water will actually become "soaked" with some hydrocarbon liquids that are also floating or dissolved in the water. Even physically softened. These are very solid pea-sized beads that are not micro-sized plastics at all. They would have to degrade a whole lot before they fall into the micro category. And they are not manufactured to intentionally have a nano-porous structure like the finer mesh porous polymer powders.
Chemicals and plastics just don't go away so safely every time.
Unlike bare skin, you can't really feel when your gloves are contaminated. So you are less likely to replace gloves when you should. With bare hands, you can feel the raw chicken juices on you, so it's pretty natural to want to wash your hands right after handling the raw chicken.
Gloves are important in medicine, but that's with proper use where doctors and nurses put on new gloves for every patient. That doesn't always happen.
I’ve never seen for example sushi portrayed with anything but bare hands
To the contrary. You take off and throw out your gloves every time you finish doing something with raw meat. It's procedure. It's habit.
You're never relying on "feel" to determine whether there are "raw chicken juices on you". Using "feel" is not reliable.
I don't know why you think food service workers aren't constantly putting on new gloves, but doctors and nurses are. Like, if you're cutting up chicken for an hour you're not, but if you're moving from chicken to veggies you absolutely are.
You are supposed to. I've seen plenty of fast food places where the gloves stay on between jobs.
I'm sure there are upscale places that are better on this point.
> You're never relying on "feel" to determine whether there are "raw chicken juices on you". Using "feel" is not reliable.
If you were just working with raw chicken, that slimy feeling on your skin is a pretty good motivator for most people to immediately wash their hands. It's more than just procedure or habit, your hands feel dirty and you want to wash that off.
> I don't know why you think food service workers aren't constantly putting on new gloves, but doctors and nurses are. Like, if you're cutting up chicken for an hour you're not, but if you're moving from chicken to veggies you absolutely are.
You absolutely are supposed to. But there's a gap in what you are supposed to do vs what actually happens in practice. Especially if you get a penny pinching boss that doesn't like wasting money on gloves.
That doesn't happen so much in medicine because the consequences are much higher. But for food? Not uncommon. There are more than a few restaurants with open kitchens that I've had to stop eating at because employees could be seen handling a bunch of things with the same set of gloves on.
It also does not help that food is often a mad rush.
I'm not sure that's reliable across people. I'm definitely like that; whenever my hands feel the least bit dirty or oily or anything, I really want to wash them. But I've run into people who have commented on the fact that I do that, and I've learned that there are lots of people who just don't have that compulsion at all.
My point is that changing gloves is something that is even less reliable and needs to be drilled in through procedure and habit. Handwashing also needs the procedure and habit, but it has the added benefit that for a good number of people there's also a physical compulsion that goes along with that procedure and habit.
I've seen enough absent-minded nose wipes on the back of gloves at Chipotle-style establishments to be pretty OK with this take.
And that's where people are watching.
I think that because I was a food service worker and it's impossible to change gloves during a rush. Nitrile gloves and sweaty hands simply do not mix. There are also many more forms of cross contamination than just raw meat to cooked food.
Gloves require your hands to be perfectly dry to put on effectively.
You can dry your hands on a towel in seconds. I don't know what you mean by "perfectly dry"...? Like, nobody needs to blow-dry their hands before putting gloves on or anything.
If you don't flap your hands around for 30+ seconds, any remaining moisture from handwashing (or sweat) makes them stick to your skin and you wind up fighting them (and about half the time, ripping a hole). A towel is not enough.
I'm not doubting your personal experience. I'm just saying it's in no way a universal rule. I'm sure experiences will be different depending on glove material, glove size, and just the different shapes of different people's hands.
But for me and for plenty of people I've worked with earlier in my life, swapping gloves was way faster and easier than washing hands again. Plus, washing your hands like 40 times in a shift is going to dry them out. It's not great.
You and your former coworkers must have magic lubricating sweat or something. I have literally never encountered someone with this opinion before in my life. And I was a combat medic before I was a line cook, so I think I know a thing or two about gloves. Even in the medical field, there were times when medics skipped the gloves because they were treating their buddies under fire and the time to get gloves on wasn't worth it to them (for anyone unfamiliar, gloves in field medicine are mostly about protecting the provider, not the patient).
But they don't generally require them to replace gloves between batches of (the same kind of) meat, or between different kinds of vegetables, or when switching from vegetables to meat, or between customers if they're on a service line. While it's recommended in those situations, I'm not sure any state mandates it.
Typo?
And it's true that you would get cleaner food prep if you used gloves properly. However, that requires a lot of gloves getting thrown away.
Genuine question: we used to simply wash our hands well before preparing food.
At what point did the wearing of disposable gloves become "better"?
Maybe a different false-positive particle type in significant amounts is on the polyethylene ones ?
Pure stearates in micro amounts would be expected to be related to mild food-grade soaps, which do end up dissolving in water or oil and do not remain solid like a relatively immobile polymer particle would do.
The gloves are not plastic.
"Chemically very similar", as in "contains long hydrocarbon chains", something which even all biological matter (lipids) has. I've looked at a few microplastic studies and many of them use pyrolysis and mass spectroscopy to detect their presence, which is going to show almost the same results for animal fat as pure hydrocarbon plastics like PE (the most common plastic by production volume) and PP.
A bit of a tangent but still on the subject of environmental pollution; the other day I found out that CO2 sensor sensitivity naturally drifts over time... So when a CO2 sensor is replaced for long term climate research, if they try to calibrate the new sensor to the old one at the time of replacement, the drift would be carried over into the new sensor even if no actual real change of CO2 occurred... Apparently there are standards to prevent this but mistakes have been identified multiple times with the methodology for setting that standard... Anyway measuring data accurately is really hard.
People do not appreciate correctness enough.
Keeping things meticulously clean on the microscopic level is a complicated task. One of the many reasons why so few EUV chip fabs even exist.
Clough prepared the substrates while wearing nitrile gloves, which is recommended by the guidance of literature in the microplastics field. But when she examined the substrates to estimate how many microplastics she captured, the results were many thousands of times greater than what she expected to find."
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The very first thing that should have been done is to run results for a substrate that hadn't been placed in the sampler. You need to know what a zero result looks like just to characterize your setup. You'd also want to run samples with known and controlled micro-plastic concentrations. Why didn't they do this? Their results are utterly meaningless if they didn't.
In surface science the baggy clear polyethylene are widely known to be cleaner than other options.
"When Good Intentions Go Bad — False Positive Microplastic Detection Caused by Disposable Gloves" - https://pubs.acs.org/doi/10.1021/acs.est.0c03742
From the study in the OP you cannot derive that current studies on microplastics are not valid. The headline framing that scientists have been measuring their own gloves, is science journalism doing what it does best...
Stearates are water soluble soaps, so any study using standard wet chemistry extraction, and that is most of them, washes them away before analysis even begins. Stearates also cant mimic polystyrene, PET, PVC, nylon, or any of the dozens of other polymers routinely found in environmental and human tissue samples.
Nothing to see here.
With what chemical structure, even? That should have been the first red flag.
"Strong claims require strong evidence". Somehow it happens pretty regularly in academia that only one method becomes acceptable and any conflicting results get herded out on technical grounds.
they tracked levels of plastic-related chemicals and fertility markers. after plastic detox 3 out of 6 couples got pregnant.
the whole research process methodology, not just measurement, miss critical assessment
How could you possibly know your analytical technique was valid if you don’t run a blank to see?
> That’s not to say that there is no microplastics pollution, the U-M researchers are quick to say. > > “We may be overestimating microplastics, but there should be none. There’s still a lot out there, and that’s the problem,”
> They found that on average, the gloves imparted about 2,000 false positives per millimeter squared area.
> Clough prepared the substrates while wearing nitrile gloves, which is recommended by the guidance of literature in the microplastics field. But when she examined the substrates to estimate how many microplastics she captured, the results were many thousands of times greater than what she expected to find.
The reason this is important is that one flawed dataset reports a hopeless situation; the other at least provides a “if we stop now” message.
Nitrile emerged only as a specialty alternative to some of the earlier synthetic chemical-resistant compounds.
They were not disposable, more expensive than the earlier synthetic compounds, also not as thick a glove was needed so they gave you protection that was never available from anything but a much more clumsy alternative. Not nearly as tactile as the disposables though, that is their big redeeming feature.
One of the major weak points of nitrile is acetone, and things like MEK or ethyl acetate, which will soak into the polymer, swell, and weaken it. If you don't let them get too weak and shred them, they will shrink back after they dry out and are still fairly OK after that But nitrile is much better against most other solvents, acids, and alkalis though. Chlorinated solvents can be kind of rough too.
I was often the first one to use nitrile in some facilities, these ended up taking over and were the typical turquoise non-disposable ones that go about halfway up the forearm. Not the skin-tight "student models" that so many people use today. Now available in various colors :)
But these early "green" gloves alone were the same ones contributing to the stereotypical look of an environmental worker, where they can be even more scary when they sometimes add a complete tyvek suit with boots, hood, respirator, and the gloves with rubber bands around the sleeves, sampling the river water while you are fishing downstream :(
The ones like we used are $16 a pair now and were never cheap enough to be disposable. They actually last many months though. Only one other old guy uses them when I go back to my old lab, everyone else was "trained" on disposables now, each lab has a wall-mounted dispenser of various sizes like they have in hospitals. The "cost savings" are so well-realized so long ago that nobody knows it's completely false :\ People go through them like water, and it's still a shitshow when they try not to.
It's really worse from a contamination standpoint because people will still wear them for an hour or two during various chemical-handling events, but also do a little paperwork or keyboard typing with the gloves on, plus doorknobs and cabinet handles they are touching are much riskier than it used to be when disposables were not an option. Just because it's such a drag to peel them off and put on a new pair 10 minutes later.
Before disposables arrived, we used to have slightly oversized non-disposables, and throw them on & off & on many times per day, I still do. Plus I often wash the gloves while wearing them not much differently than washing my bare hands, mainly to get rid of chemicals using (very) hot soap & water or even using other strong solvents like heptane to rinse off heavier chemicals and oils. Probably about as particle-free as you can get except for what is floating around in the ambient air. Not like the skin-tight almost too-thin gloves people settle for now where they need to be peeled back off inside-out and thrown away each time.
By this point in the 21st century there are dedicated representatives of the glove manufacturers making high-touch sales calls, so there have got to be some bonuses that didn't exist that many decades ago.
> To be honest, after reading some of these microplastics papers I'm starting to suspect most of them are bullshit. Plastics are everywhere in a modern lab and rarely do these papers have proper controls, which I suspect would show that there is a baseline level of microplastic contamination in labs that is unavoidable. Petri dishes, pipettes, microplates, EVERYTHING is plastic, packaged in plastic, and cleaned using plastic tools, all by people wearing tons of synthetic fibers.
> We went through this same nonsense when genetic sequencers first became available until people got it into their heads that DNA contamination was everywhere and that we had to be really careful with sample collection and statistical methods. [1]
But as mentioned elsewhere in the thread, everyone knows that it's possible and take measure to mitigate it.
A paper that said those mitigations were insufficient or empirically found not to work would be interesting. A paper saying "you should mitigate this" is... not very interesting.
From the article:
> They found that on average, the gloves imparted about 2,000 false positives per millimeter squared area.
I dunno, that seems like a lot of false positives. Doesn’t that strongly imply that overestimation would be a pretty likely outcome here? Sounds like a completely sterile 1mm^2 area would raise a ton of false positives because of just the gloves.
Then the tested result is Actual Sample Result - Negative Sample Result.
So you'd expect a microplastic sample to have 2,000 plus N per mm^2, and N is the result of your test.
It took years to figure out proper methods and many subfields have their own adjusted procedures and sometimes even statistical models. At least with DNA you could denature it very effectively, I’m not sure how they’re going to figure out the contamination issue with microplastics.
I can't imagine wafting your hands over the tubes would change the plastic amounts substantially compared to whatever negative controls the papers used. But again, I am not an expert on this kind of analytical chemistry. I always worry more about batch effects. But it does seem like microplastics are becoming the new microbiome.
Maybe so, but plastics are also everywhere in our daily lives, including on the food we eat and in the clothes we wear. As we speak I just took some eggs out of a plastic carton, unwrapped some cheese from plastic wrap, and got oatmeal out of a plastic bag. The socks and pants I'm wearing are made of polyester.
If plastics cause contamination in a lab, would you not also expect similar contamination outside of the lab?
When I was an automation engineer at a lab, each liquid handler alone could go through several pounds of plastic pipette tips in a single day. All of that is made out of plastic and coated in a different thin layer of plastic to change the wettability of the tip. Even the glassware often comes coated in plastic and all these coatings are the thin layers most likely to create microplastics from abrasion (like the force of the pipette picking up the tip!). Throw all the packaging on top of that and there is just an insane amount of plastic.
The only place I've seen more plastic consumed is industrial and food manufacturing where everything is sprayed and resprayed with plastic coatings to reduce fouling.
If you're around plastic a lot you're ingesting a lot and if you're not, you're not.
So the conclusion would be that plastics "sheds" and you should avoid it in packaging, kitchen utensils, etc
So, not that microplastics don’t exist, but that they don’t exist to the same degree as in a lab environment.
These are soap-like chemicals used as mould release agents on gloves, but what also means are chemically similar to plastics when analyzed by some techniques and under a microscope will spontaneously form micelle-structures which look very similar to microplastics (you can't exactly get in there and poke them).
Now why would anyone do that when the headline already supports their uninformed opinion?
Yeah, and my primitive home-grown analysis then carries the same weight as those from experts with professional equipment? Oh come on...
This is a very scientific way of thinking. It's only gotten a bad rap on account of people using it to attack others' research and then(crucially) failing to perform their own.
You might have heard that it wasn't tested for reducing transmission, i.e. whether the vaccines make it less likely that an infected, vaccinated person would transmit the virus to someone else... Which it wasn't, because uhhh... how would you?
They tested it for safety, reduction in symptomatic infection rate and reduction in infection severity.
You should set aside your conclusions for a bit and take an earnest effort at learning some of the details of this stuff if you want to "do your own research" etc. It is clear you are misunderstanding some pretty fundamental things that are actually easily understandable if you approach them with honest curiosity!
You can literally look up the trial designs and they just say right on them exactly what they're testing for and how they're doing it.
At some time you realize you can't repeat all the test at home, because it would be full of mice and transgenic plants and a huge particle collider and ... Also, there are a lot of very hard topics. So you must trust the system, but not too much.
* Big pharma wants to sell drugs and get money.
* The FDA wants to cover they ass and get money.
* Journalist want to publish bleeding stories and get money.
[There is also an optimistic version where all of them want the best for humanity.]
All of them together are making a quite good job, and you can go to the pharmacy at the corner and be quite confident that you will get the cure for a lot of illness with a low risk. In some threads people ask for most tests, in some threads people ask for faster approval. It's a hard trade off, and I'm happy I don't have to make the decision [3].
In 2020 there was a lot of misinformation in both directions. From politicians to youtubers, form individual crackpots to professors in the university. In many cases you realize they may not even understand the difference between a virus and a bacteria, in other cases they say that the "control group" is an unrelated bunch of guys in another city.
Science is about doing your own research, but doing your own research is super hard. As a rule of thumb, if the FDA and the European equivalent agree, it's probably ok [4], but cross your fingers just in case.
[1] Whatever "serious" mean. It's a hard question.
[2] And real "peer review", not a comment section in a web page.
[3] Somewhat related https://www.fortressofdoors.com/four-magic-words/
[4] Do you trust the contractor+regulations that installed the elevator at your building? It's another trade off of as cheap as possible and enough regulations to avoid appearing in the front page of all newspapers everyday.
Those trials unequivocally showed extremely high effectiveness and extremely high safety.
The people who say otherwise are simply wrong in this case. No matter how much philosophizing you or they want to do on epistemology. If they want to demonstrate otherwise, they need to conduct their own trials, ideally large, randomized, blinded, placebo-controlled trials.
> in other cases they say that the "control group" is an unrelated bunch of guys in another city.
This is not how trials work and you should go "do your own research" on the basics of the methodology before you opine on higher-order things like vaccines etc.
If you want to ruin your day, take a look at the hydroxychloroquine [retracted] paper by Raoult. Who is the control group? Why was it reported in the press as a 100% cure if the only death was in the trial group?
I agree that the trial to prove the effectiveness and safety of the covid-19 vaccines were much better designed. One of the reasons is that to get the approval of the FDA they must dot the i and j and cross the t and f.
Not for the average adult human on planet Earth, no.
Fifty percent of people are of below average intelligence. Of the 50% that remain only a fraction have access to the equipment necessary to replicate any given experiment, of that fraction only a small percentage will have the knowledge, skills, and abilities to accurately replicate any given experiment, of that tiny fraction only a much tinier fraction will have the KSA's to interpret those results in a meaningful way.
Science should replicate. That does not automatically imply that YOU should be the one replicating it.
For the average person science should mean knowing how to determine if someone is more qualified than they are and listening to them, or at least listening to the general consensus of those who are more qualified when such a consensus exists.
Yes, other peoples goals don't always align perfectly with yours, but the simple truth is that you aren't qualified or even capable of understanding everything in the world. When it comes to those subjects you must be adult enough to understand and work within your limitations.
Honestly, do you really believe that people who sacrificed large parts of their lives to become researchers are in it for the money, or out to get you? These are brilliant people who choose to take a career path that doesn't really pay well. When 99% of them tell you something is safe, Occam will tell that it's a pretty safe bet the weirdos on the fringe are just plain wrong.
They mean that they went online and found blogs and YouTube videos that agree with whatever crackpot view they already held.
The issue with picking people and organizations to trust (which you absolutely should do) is that the average person isn’t even able to evaluate what qualified means. And RFK jr. is the guy appointing the “qualified people” who run things. On paper many of them are qualified, but in reality they’re crackpots.
You have to dig a level deeper and understand that this set of qualified people are actually just nuts who essentially performed the scientific equivalent of a coup because their ideas couldn’t win on merit.
I agree. But how do you that without researching? Who makes the list of trustful institutions?
Let's pick homeopathy. The pharmacy in the corner of my home sells homeopathy too. There are even some curses in some universities [in Germany?] [I searched in MY university. Apparently there is no curse for human medicine, but there is a curse for veterinary https://www.fvet.uba.ar/?q=homeopatia .] Can we agree homeopathy is not real? How do you know?
So my standard at the time was that I’d take it if the FDA and at least one other developed country approved it.
My wife was one of the first pregnant women to get the vaccine (outside of trials) because she’s an ER doctor, and she’s had regular follow-up surveys from the CDC for years.
Do you have a link to the exact quote?
IIRC they have a 95% reduction in hospitalization rate, measured in a double blind human trial. [Compare that with the vector virus and inactivated virus vaccines, that have like a 65% reduction in hospitalization rate, measured in a double blind human trial.]
Still false
https://www.rmit.edu.au/news/factlab-meta/viral-pfizer--admi...
Please nobody listen to his person. There is nothing scientific about ignoring the experts to instead behold the opinions of the uninformed.
The world is too large, too complex, and too nuanced for the layman's opinion to be worth much. When someone is unqualified treat their opinion as equal to every other unqualified persons opinion. Include your own in that assessment. Be honest, what qualifications do you have that make your assessment of the evidence more valid than any other random street person's in the given field? It's very likely the answer is "none". So lend your own opinion the level of respect it has earned. Be honest with yourself about what that level is.
"There is a cult of ignorance in the United States, and there has always been. The strain of anti-intellectualism has been a constant thread winding its way through our political and cultural life, nurtured by the false notion that democracy means that 'my ignorance is just as good as your knowledge.'” ― Isaac Asimov
This has a very, "Trust us, we're with the government." feel to it.
I enjoy Asimov's writing immensely but if you think quotations are some kind of mic drop, I'll leave you with this one.
"The question then is not whether or not a girl should be touched. The question is merely where, when, and how she should be touched" ― Isaac Asimov
It is self evident that moderm science is too complex for the average person to understand, and fifty percent of us are less intelligent than even that.
I think you're grossly overestimating the complexity of most modern science outside of physics and mathematics (and computing, as an intersection of the two).
Good science is actually pretty easy to explain most of the time. It may take a long time to become a domain expert thst can perform novel research in a field but it it's well within the understanding of most people to have a single topic explained to them by an expert.
In fact, that very thing happens in courtrooms all the time.
Your condescending attitude is why people don't trust authorities and with good reason. If you can't help people understand science, it's you that doesn't understand it.
Furthermore, I hope you realize how close your "self-evident" logic is to a lot of extremely gross and genocidal ideologies of the past and present.
The truth is that we're both likely right to some extent, and wrong to some extent.
I now think that maybe there is no hard and fast rule one can apply to every situation to decide when one should decide for themself or just trust the experts. The optimal solution likely varies greatly depending on the specifics of the given situation, and it's very reasonable that we would have two very different takes about it.
The COVID vaccine is a triumph of human ingenuity and we should all feel incredibly proud it exists. It was the moon landing of our time.
More broadly, vaccines have probably saved more human lives than any other medical technology in history.
It is generally bad practice to so drastically twist somebody’s words to make them say the opposite of what they’re saying. Carl Sagan would not agree with you.