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Nitrile and latex gloves may cause overestimation of microplastics
- giantg2 7mo agoClassic. 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.
- thebruce87m 7mo agoI thought that exact thing and opened the comments to see you’d already commented with it. There is a “case files” podcast on it that I found quite good.
- vlz 7mo agoThis seems to be the Casefile episode about the "Phantom of Heilbronn" https://casefilepodcast.com/case-178-the-woman-without-a-face/ https://casefilepodcast.com/case-178-the-woman-without-a-fac...
- alsetmusic 7mo agoThat's incredible. Though the effect of this will be claims that microplastics don't exist while no one in that case claimed that murders didn't happen. Happy to have learned about an interesting historical oddity either way.
- kQq9oHeAz6wLLS 7mo agoI don't think anyone will claim microplastics don't exist, but people will definitely be skeptical of articles about how many there, and where they're found. At worst, I'd expect to see people disregarding the threat, not disregarding the presence of the microplastics themselves.
- alsetmusic 7mo agoI see you're not a fan of hyperbole. Though I sorta meant it, so maybe it's not.
- Lerc 7mo agoI'm not sure if they have established a threat. I thought it was mostly hypothesised or very locally specific harms. 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.
- dijit 7mo ago[dead]
- cachius 7mo agoThe Phantom of Heilbronn, often alternatively referred to as the Woman Without a Face, was a hypothesized unknown female serial killer whose existence was inferred from DNA evidence found at numerous crime scenes in Austria, France and Germany from 1993 to 2009. 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. https://en.wikipedia.org/wiki/Phantom_of_Heilbronn https://en.wikipedia.org/wiki/Phantom_of_Heilbronn
- pell 7mo agoInterestingly, contamination of the forensic equipment was considered early on already. However, due to the geographic area of the findings and initial negative control tests using fresh swabs, they ruled it out.
- MagicMoonlight 7mo agoThat’s why you’re supposed to submit an unused swab with the samples, so that they can make sure the swab itself isn’t the source.
- FartyMcFarter 7mo agoPlot twist: the woman making the DNA collection swabs was the serial killer.
- crest 7mo agoIt's the perfect cover!
- cr125rider 7mo agoSomeone should make a show about that… her name could be Dexterette!
- Imustaskforhelp 7mo agoSad to see that you are downvoted. It's sad seeing that Hackernews doesn't understand Dexter memes.. (Amazing show, Highly recommended) The Bay Harbor Butcheress[0] :) [0]: https://en.wiktionary.org/wiki/butcheress https://en.wiktionary.org/wiki/butcheress (at First I made it as a joke but turns out that butcheress is a real term, indeed)
- oharapj 7mo agoThis isn’t Reddit. Awesome bacon sauce posts generally aren’t appreciated
- no_shadowban_3 7mo ago[dead]
- deleted 7mo ago[deleted]
- EasyMark 7mo agoturns out she's also calling from inside the house!
- fweimer 7mo agoThey weren't DNA collection swabs, but sterile swabs intended for medical use.
- ErigmolCt 7mo agoWhen your methods get really sensitive, you stop just measuring the world and start measuring your own process too
- Perepiska 7mo agoto save time: https://en.wikipedia.org/wiki/Phantom_of_Heilbronn https://en.wikipedia.org/wiki/Phantom_of_Heilbronn
- wewewedxfgdf 7mo agoThat'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?
- _fizz_buzz_ 7mo agoThe article specifically says the opposite.
- isodev 7mo ago[flagged]
- lpcvoid 7mo agoWhere do I find this info?
- preuceian 7mo agoIn the acknowledgements section. However, after reviewing it, I’m not sure what or who I should be looking for, so I’m not entirely sure what the OP is hinting at. At first glance, nothing appears suspicious, though I should note that I’m not familiar with any of the authors and haven’t looked into them further.
- deleted 7mo ago[deleted]
- haunter 7mo agoWho? > The authors acknowledge funding from the College of Literature, Science, and Arts at the University of Michigan. R. L. P. was supported by an NSF Graduate Research Fellowship (NSF-GRFP) DGE-2241144. M. E. C. was partially supported by the University of Michigan Rackham Graduate School through a merit and predoctoral fellowship.
- Tenemo 7mo ago> The authors acknowledge funding from the College of Literature, Science, and Arts at the University of Michigan. R. L. P. was supported by an NSF Graduate Research Fellowship (NSF-GRFP) DGE-2241144. M. E. C. was partially supported by the University of Michigan Rackham Graduate School through a merit and predoctoral fellowship. The authors would like to acknowledge the professors and students of the Mapping, Measuring, and Modeling Microplastics in the Atmosphere of Michigan team for their support and helpful discussions. The authors thank Jennifer Connor, Curtis Refior, Amy Pashak, Megan Phillips, Josh Hubbard, Bill Joyce, and David Lee for their community partnership. The authors would also like to thank former Dean Anne Curzan from the College of Literature, Science, and the Arts at the University of Michigan for funding this work through the “Meet the Moment” grant program. The authors acknowledge technical support from the Michigan Center for Materials Characterization. Is there anything wrong here? Not sure I understood your comment
- darkerside 7mo agoSo 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?
- sd9 7mo agoHuh, good point
- stef25 7mo agoWell, it could mean more microplastics occur in an unnatural environment (the lab) containing much more plastics than in a typical home setting. 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
- xienze 7mo agoYes? Most people don’t live their entire lives in a lab wearing nitrile gloves, so there’s an argument to be made that the concentration of microplastics found in that setting is not reflective of everyday life. So, not that microplastics don’t exist, but that they don’t exist to the same degree as in a lab environment.
- formerly_proven 7mo agoI wouldn't be surprised if e.g. all these paper-thin synthetic (plastic) disposable parts and fabrics used in labs shed microplastics way more than e.g. synthetic fabrics designed to be survive a machine wash a few dozen times, or upholstery meant to withstand tens of thousands of sitting cycles, nevermind solid plastics (e.g. reusable food containers, furniture surfaces).
- jofer 7mo agoIt's not microplastics coming from the gloves. It's particles of the powder used to coat the gloves and keep them from sticking. Different composition, but similar and easily mistaken.
- 7mo ago
- throwup238 7mo agoCalled 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] [1] https://news.ycombinator.com/item?id=40681390 https://news.ycombinator.com/item?id=40681390
- gww 7mo agoI haven't really read the studies but shouldn't they have negative controls to negate these effects? Wouldn't that let the author's correct for a baseline contamination level in the lab?
- codebje 7mo agoOn the one hand, hundreds or perhaps thousands of studies might be wrong. On the other hand, this one might be wrong. Who's to say?
- estearum 7mo agoNot even that! This study doesn't even say contamination is causing overestimation. It says that it's possible. 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.
- xienze 7mo ago> Not even that! This study doesn't even say contamination is causing overestimation. It says that it's possible. 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.
- globemaster99 7mo agoCarl 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.
- harladsinsteden 7mo ago> Do your own assessment. Yeah, and my primitive home-grown analysis then carries the same weight as those from experts with professional equipment? Oh come on...
- Dilettante_ 7mo agoDoesn't have to be one or the other. Trust, but verify? Experts make mistakes, professional equipment can be mishandled. Don't take anybodies word, look at the evidence for yourself. 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.
- globemaster99 7mo agoTrue, trust but verify and start questioning things. Science is now more politicized more than ever by politicians. COVID vaccines are not even tested. I didn't said this. Pfizer and Moderna CEO said this in EU parliament hearing.
- estearum 7mo agoLol, the COVID vaccines went through some of the largest randomized controlled trials ever conducted and had some of the best safety and efficacy results ever seen. 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.
- khalic 7mo agoThis study assumes everybody is oblivious to contamination, and explicitly says they can't differentiate. Not useful and bordering on the tautological
- deleted 7mo ago[deleted]
- ErigmolCt 7mo agoThe non-trivial part isn't contamination per se, it's that the contaminant is chemically and spectroscopically similar enough to evade standard discrimination
- inglor_cz 7mo agoWhile 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.
- amelius 7mo agoBy that same effect we probably introduced life on Mars already.
- firesteelrain 7mo agoIt’s not improbable that some micro organism might have escaped the safety protocols. The likelihood it is still alive is low
- lokinork 7mo ago[dead]
- BoredPositron 7mo agoITT people that only read the headline.
- thomasgeelens 7mo agothis 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?
- refulgentis 7mo agoIt wasn't an oversight? They sighted it immediately, hunted it down, then wrote it up for you.
- fHr 7mo agoDidnt 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.
- keeperofdakeys 7mo agoReminds me of the story of Polywater. https://en.wikipedia.org/wiki/Polywater https://en.wikipedia.org/wiki/Polywater
- zahlman 7mo ago> a hypothesized polymerized form of water With what chemical structure, even? That should have been the first red flag.
- tasuki 7mo agoSo you're saying microplastics aren't a problem, because there's too much microplastics in gloves??
- kQq9oHeAz6wLLS 7mo agoI don't see anyone saying they aren't a problem.
- daedrdev 7mo agoIf you the read article, you would see it explains that what they release are not microplastics. They are instead a soap used to get them to unstick from their mold in production.
- nslsm 7mo ago[flagged]
- andersonpico 7mo agosock puppet account
- zug_zug 7mo agoThis is good news, probably. We'll have to wait and see which studies replicate and which don't.
- ErigmolCt 7mo agoLots of signal, lots of noise, and slowly figuring out which is which
- dust42 7mo agoSo basically the gloves that kitchen staff now must wear means we get an extra dose of micro plastics? Yikes.
- firesteelrain 7mo agoIt says similar. “ 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.
- sfn42 7mo agoI'm still not aware of any reason to worry about micro plastics. As far as I know they seem harmless?
- SapporoChris 7mo agoIt is true that there is not currently conclusive proof that micro plastics are a significant risk to human health. However, this is the same line the tobacco industry used for decades even though they knew different.
- NiloCK 7mo agoIs there any specific evidence that they are a risk to human health? 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.
- 7mo ago
- krautburglar 7mo ago[flagged]
- jordanb 7mo agoJust the fact that the lab gets to publish something that's regime-friendly is beneficial to them. Why was the study funded through the humanities department?
- krautburglar 7mo agoI have made an inconvenient statement, and you have asked an inconvenient question, so off to the gallows with us. Yo dang, I hope YC is paying you enough to end up on St. Peter's naughty list, because that is where you are all headed.
- Mordisquitos 7mo agoI'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.
- p-e-w 7mo ago> I'm amazed that wasn't taken into account! 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.
- johnbarron 7mo ago>> I'm amazed that wasn't taken into account! This was taken into account: https://news.ycombinator.com/item?id=47563392 https://news.ycombinator.com/item?id=47563392
- timr 7mo agoYou found a paper saying that contamination is possible. That doesn’t mean that most of these plastic studies are doing the necessary controls, let alone the (almost impossible) task of preventing the contamination in a laboratory setting where nanomolar detection levels are used to make broad claims.
- idiotsecant 7mo ago
- nobodyandproud 7mo agoFinally some good news.
- creesch 7mo agoGood news with a note: > 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,”
- nobodyandproud 7mo agoAnd with some actual numbers, when digging in further: > 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.
- johnbarron 7mo agoA 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 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.
- RobGR 7mo agoWhy do you say "nothing to see here" ? The existence of the earlier paper does not imply that procedures corrected for this afterwards. Is there any published protocol for a study since that first article that mentions avoiding stearate powder from gloves ?
- maltyxxx 7mo ago[dead]
- ErigmolCt 7mo agoSo the takeaway is: we've been accidentally adding "microplastics" with the very gloves we use to avoid contamination. That's almost poetic
- rflrob 7mo agoStearates aren’t microplastic plastics, though, they’re just similar enough under a microscope and in some chemical analyses. Without knowing which stearates glove manufacturers use (or what exactly it is about microplastics that is harmful), it’s difficult to to say whether the stearates will have the same harmful effects.
- beloch 7mo ago"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." ------------------ 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.
- MinimalAction 7mo agoYeah, where is their control sample without any substrate on the sampler?
- s0rce 7mo agoNo substrate in the sampler means there would be nothing to test. Can't tell if you are joking.
- s0rce 7mo agoThat does seem like an oversight. We routinely run process blanks for elemental analysis at my job. I guess if the metal substrates had specifications on no particles you might skip this, obviously a big mistake if another step (ie. handling with gloves) introduced contamination. In surface science the baggy clear polyethylene are widely known to be cleaner than other options.
- s0rce 7mo agoI 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.
- legitster 7mo agoI 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.
- userbinator 7mo agoI think it's partly deliberate and partly ignorance of chemistry. We are simply finding that biological matter is nearly indistinguishable from man-made microplastics.
- ktokarev 7mo agothe_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
- EPWN3D 7mo agoThe 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.
- suzzer99 7mo agoPeter Attia (I know, but I trust his ability to synthesize medical research) did a whole deep dive on this and IIRC determined that for the most part, it wasn't a big concern for anyone with remotely normal consumption patterns.
- queenkjuul 7mo agoGood, glad human consumers are the only life on earth that could be affected
- eigenspace 7mo agoSo, I think that while it's true that we haven't really demonstrated any tangible harms of microplastics, and there is a lot of alarmism around it, I think the concern is more rational than it might appear. 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.
- AndrewKemendo 7mo agoThe 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/S0165993618305247 https://www.sciencedirect.com/science/article/pii/S016599361...
- bluerooibos 7mo agoThey found microplastics in the snow in Antarctica and in human embryos right? So this seems rather redundant.
- userbinator 7mo agoBut 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.
- fuzzfactor 7mo agoDecades 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.
- tsoukase 7mo agoOnly Heisenberg's uncertainty principle is not affected by the observer effect.
- Geee 7mo agoI 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.
- refurb 7mo agoNobody 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?
- jongjong 7mo agoStudies 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.
- rblion 7mo agoAlso consider how many people have to wear them every day or close to. How much they interact with food and packages that most of us eventually touch. Food for thought.
- relation_al 7mo agoDid we also use the simple qualifying predicate "may cause" back when we were "certain"?