alt Hacker NewsNitrile and latex gloves may cause overestimation of microplastics
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Classic. This is like that female serial killer in Europe that turned out to actually just be DNA from a woman making the DNA collection swabs.
The various "OMG MICROPLASTICS" studies always smacked of alarmism. No one has actually identified tangible harms from microplastics; it's just taken as a given that they are bad. So this fueled a bunch of studies that tried to find them everywhere. Even the authors of this study go to great pains to not challenge the dogma that microplastics are existentially terrifying. So I fully expect we'll still be panicking over vague, undefined harm whenever we find microplastics somewhere.
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.
I guess with Raman I can see this being misidentified but I do testing with FTIR at my job, although not often for microplastics and we often detect olefins and stearates and they don't seem to get confused. I didn't realize there were stearates on nitrile gloves, we'll need to be more careful of that. We are always weary of protein contamination from people, or cellulose/nylon from clothing.
This is good news, probably. We'll have to wait and see which studies replicate and which don't.
So basically the gloves that kitchen staff now must wear means we get an extra dose of micro plastics? Yikes.
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.
"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.
This study assumes everybody is oblivious to contamination, and explicitly says they can't differentiate. Not useful and bordering on the tautological
"The researchers used air samplers which are fitted with a metal substrate. Air passes through the sampler, and particles from the atmosphere deposit onto the substrate. Then, using light-based spectroscopy, the researchers are able to determine what kind of particles are found on the substrate.
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.
Only Heisenberg's uncertainty principle is not affected by the observer effect.
I once worked in a meatball factory. I touched almost every single meatball with nitrile gloves. There's probably a lot of earlier process steps where humans are touching the food with gloves.
I had always assumed there was a methodological failure that kept getting replicated. There were enough articles like "scientists find microplastics at bottom of peat bog" that really made me dubious of the claims.
"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.
So the takeaway is: we've been accidentally adding "microplastics" with the very gloves we use to avoid contamination. That's almost poetic
Reminds me of the story of Polywater. https://en.wikipedia.org/wiki/Polywater
Studies are extremely difficult to get right. I'm generally a little bit skeptical of data for this reason.
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.
They found microplastics in the snow in Antarctica and in human embryos right? So this seems rather redundant.
The way this study was done makes perfect sense for finding this cross-contamination issue, but does not actually address how microplastics samples are extracted and found in sampling studies.
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...
the_plastic_detox documentary on netflix promotes the idea that microplastics cause infertility. this is based on 6 couples 90 days experiment.
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
Nobody ran a control? It’s the most concept of experimentation.
How could you possibly know your analytical technique was valid if you don’t run a blank to see?
While we are used to associate "the observer effect" with particle physics, it can appear in biology and/or chemistry as well.
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.
this feels like such a weird oversight in such a controlled environment: "oh my bad it was the gloves!" I wonder in how many other studies this happened?
Didnt they use for newest studies to detect microplastic in placentas I think only non plastic omitting alternative gloves and material. Can't recall there it was specifically mentioned in a worldclass ARTE docu about microplastics maybe some ARTE Ultras here can recall.
ITT people that only read the headline.
A rediscovery...six years later:
"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.
Decades ago the only modern disposable gloves like these were "natural" latex which served medical professionals well but were miserably inadequate for chemical use. So nobody even thought about using them with aggressive industrial materials.
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.
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So the problem is these particles are literally flying off the gloves of the scientists wearing them to the point it's interfering with the experiment and so... it's less of a problem?
Called it!
> 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]
So you're saying microplastics aren't a problem, because there's too much microplastics in gloves??
As per usual, they get the result then go back to do the study. Been happening in economics forever too.
That's a relief. Now I can stop worrying about microplastics. Just like the environment - we don't hear much about it any more, so they must have sorted that out too. Didn't they? Did they?
Carl Sagan was right all along. Always question science, never trust these so called experts, do your own assessment, research and thinking. This must be another global climate change scam.
I'm amazed that wasn't taken into account! Many years ago, in the final year of my Biology degree, I did a paid summer internship at an Evolutionary Biology lab here in Spain, assisting in a project where they were researching relationships between metal ion accumulation (mostly zinc) and certain SNPs (≈"gene varieties"). A lot of my work was in slicing tiny fragments of deep-frozen human livers and kidneys in a biosafety cabinet over dry ice.
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.