[HN Gopher] Nitrile and latex gloves may cause overestimation of...
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Nitrile and latex gloves may cause overestimation of microplastics
Author : giuliomagnifico
Score : 483 points
Date : 2026-03-29 09:46 UTC (13 hours ago)
(HTM) web link (news.umich.edu)
(TXT) w3m dump (news.umich.edu)
| giantg2 wrote:
| 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.
| thebruce87m wrote:
| I 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 wrote:
| This seems to be the Casefile episode about the "Phantom of
| Heilbronn"
|
| https://casefilepodcast.com/case-178-the-woman-without-a-
| fac...
| alsetmusic wrote:
| That'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 wrote:
| I 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.
| Lerc wrote:
| I'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.
| cachius wrote:
| The 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
| pell wrote:
| Interestingly, 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 wrote:
| That'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.
| giantg2 wrote:
| That only works if both swabs suffered the same
| contamination. If the contamination is sporadic, then it
| won't show.
| FartyMcFarter wrote:
| Plot twist: the woman making the DNA collection swabs was the
| serial killer.
| crest wrote:
| It's the perfect cover!
| cr125rider wrote:
| Someone should make a show about that... her name could be
| Dexterette!
| Imustaskforhelp wrote:
| Sad 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 (at First
| I made it as a joke but turns out that butcheress is a
| real term, indeed)
| oharapj wrote:
| This isn't Reddit. Awesome bacon sauce posts generally
| aren't appreciated
| fweimer wrote:
| They weren't DNA collection swabs, but sterile swabs intended
| for medical use.
| ErigmolCt wrote:
| When your methods get really sensitive, you stop just measuring
| the world and start measuring your own process too
| wewewedxfgdf wrote:
| 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?
| _fizz_buzz_ wrote:
| The article specifically says the opposite.
| darkerside wrote:
| 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?
| sd9 wrote:
| Huh, good point
| stef25 wrote:
| Well, 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 wrote:
| Yes? 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 wrote:
| I 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 wrote:
| It'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.
| XorNot wrote:
| If you read the article you'd find that what they are finding
| are _not_ microplastics - they 're stearates[1]
|
| 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).
|
| [1] https://en.wikipedia.org/wiki/Stearic_acid
| scorpionfeet wrote:
| "if you read the article"
|
| Now why would anyone do that when the headline already
| supports their uninformed opinion?
| jevogel wrote:
| No, the gloves leave stearates (not plastic, but similar
| looking particles) residue on contact. So there are not
| literally micro plastics flying off the gloves. Read the
| article.
| throwup238 wrote:
| 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]
|
| [1] https://news.ycombinator.com/item?id=40681390
| gww wrote:
| I 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 wrote:
| On 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 wrote:
| Not 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 wrote:
| > 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.
| estearum wrote:
| The way you mitigate this is by using negative samples.
| Basically blank swabs/tubes/whatever that _don 't_ have
| the substance you're testing in it, but that is handled
| the same way.
|
| 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.
| throwup238 wrote:
| That has happened many times in scientific research. The
| aforementioned fad in DNA sequencing was one such case
| where tons of papers before proper methods were developed
| are entirely useless, essentially just garbage data.
| Another case is fMRI studies before the dead salmon
| experiment.
| throwup238 wrote:
| That was the difficulty with DNA: how do you make that
| control if everything is contaminated and minor variations in
| protocol (like wafting your hands over the samples one too
| many times) changes the baseline?
|
| 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.
| gww wrote:
| I have worked at a sequencing center before. DNA
| contamination is easier to mitigate because the lab
| disposables aren't made out of what you are testing.
| Disposables are almost always plastic and tend to have
| minimal DNA contamination. Environmental DNA contamination
| is largely mitigated with PCR hoods and careful
| protocols/practices. However, these procedures don't
| mitigate DNA contamination at the collection level, which
| is likely where the statistical models you mentioned help.
|
| 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.
| pton_xd wrote:
| > 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.
|
| 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?
| Snoozus wrote:
| You would, but if you do studies that claim that
| microplastics accumulate in our bodies or even in out brains
| it makes a difference.
| throwup238 wrote:
| I think you underestimate how much plastic is consumed in a
| lab doing experiments or analysis. I suspect it's an order of
| magnitude or two more than people are regularly exposed to at
| home or other non-industrial settings.
|
| 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.
| creesch wrote:
| > 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,"
| andersonpico wrote:
| shouldn't you be particularly attentive to your bias then? an
| article came out that _seems_ to confirm your previous belief
| that you arrive at without really testing? like everyone itt
| that is looking like the comments of an steven crowder comment
| section in a post about climate change
| globemaster99 wrote:
| 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.
| harladsinsteden wrote:
| > 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_ wrote:
| Doesn'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 wrote:
| True, 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 wrote:
| Lol, 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.
| mapontosevenths wrote:
| A man who represents himself as a lawyer has a fool for a
| client. A man who "does his own research" has a fool for
| a researcher.
| gus_massa wrote:
| But science is about doing your own research! The idea is
| that science results are based on evidence that is
| published in serious [1] peer review [2] journals.
|
| 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.
| estearum wrote:
| This is all a very fun thought experiment and whatnot but
| the reality is the COVID vaccines went through gigantic
| randomized controlled trials, our absolute best known
| method (by a gigantic margin) to figure out what is true.
|
| 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.
| gus_massa wrote:
| >> _in other cases they say that the "control group" is
| an unrelated bunch of guys in another city._
|
| 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.
| mapontosevenths wrote:
| > But science is about doing your own research!
|
| 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.
| sarchertech wrote:
| There's nothing wrong with doing your own experiments as
| long as you understand your limitations. But that's not
| what people mean when they say they "did their own
| research".
|
| 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.
| gus_massa wrote:
| > _For the average person science should mean knowing how
| to determine if someone is more qualified than they_
|
| 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?
| sarchertech wrote:
| To be fair, when the Covid vaccine was being rushed to be
| approved, I didn't 100% trust that Trump wouldn't
| pressure the FDA to approve without being confident it
| was safe.
|
| So my standard at the time was that I'd take it if the
| FDA and at least one other developed country approved it.
| gus_massa wrote:
| Here in Argentina we approved the Sputnik vaccine. It was
| approved only here and in Russia. And here it was
| approved not by the standard office (ANMAT), but by a
| special resolution of the Health Ministry.
| gnabgib wrote:
| We could find it in Canada too (due to distribution it
| wasn't super common)
| sarchertech wrote:
| We have more data on COVID vaccines that nearly every
| drug in existence.
|
| 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.
| gus_massa wrote:
| >> _COVID vaccines are not even tested_
|
| 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.]
| pfdietz wrote:
| Which reminds me, I need to arrange my biannual COVID
| booster.
| gus_massa wrote:
| Is it a only covid-19 booster or does it include a few of
| the other coronavirus floating around?
| pfdietz wrote:
| Just COVID-19. I do get other shots though, for example
| the annual flu shot and most recently an RSV shot (not
| the one I had participated in a clinical trial for.)
| croes wrote:
| The claim wasn't it wasn't tested but that it wasn't
| tested for transmission prevention.
|
| Still false
|
| https://www.rmit.edu.au/news/factlab-meta/viral-pfizer--
| admi...
| mapontosevenths wrote:
| > Don't take anybodies word, look at the evidence for
| yourself.
|
| 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
| parineum wrote:
| > The world is too large, too complex, and too nuanced
| for the layman's opinion to be worth much.
|
| 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
| mapontosevenths wrote:
| I am right and I suspect you know it... you just don't
| like the way it makes you feel. Hence your focus on vibes
| and ad hominums rather than reason.
|
| 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.
| ivell wrote:
| It is partially correct. Except make sure you have the
| necessary skills to question the science. Intuition in these
| things are quite misleading. Don't start questioning cancer
| reports just because you don't feel sick.If you really don't
| trust it, get a relevant medical degree or take second opinions
| from those who are really qualified and not some quacks.
| Otherwise you would just end up dead.
| greenavocado wrote:
| The problem with your claim that the plebs are incapable of
| research because they don't have equipment and are dumb is
| the wholesale erosion of belief in institutions after the
| COVID "vaccine" situation
| troad wrote:
| I reject the scare quotes you're putting around the word
| vaccine.
|
| 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.
| ivell wrote:
| I assume you are expert in some domain. How would you feel
| if someone who is not familiar with your domain comes in
| and start questioning your expert judgment? Even in your
| domain probably being an expert means having access and
| expertise of equipments. Without that I cannot imagine
| having expertise to judge what is correct and what is wrong
| for that domain.
| Forgeties79 wrote:
| I guarantee you Carl Sagan was not telling you to dismiss
| experts and he very much understood climate change was real. He
| literally testified before Congress on it, likely decades
| before you were even born.
|
| 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.
| baublet wrote:
| Weaponized ignorance.
| conception wrote:
| I assure you, you do not have the background to properly assess
| the research.
| khalic wrote:
| This study assumes everybody is oblivious to contamination, and
| explicitly says they can't differentiate. Not useful and
| bordering on the tautological
| ErigmolCt wrote:
| The 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 wrote:
| 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.
| amelius wrote:
| By that same effect we probably introduced life on Mars
| already.
| firesteelrain wrote:
| It's not improbable that some micro organism might have
| escaped the safety protocols. The likelihood it is still
| alive is low
| lokinork wrote:
| As per usual, they get the result then go back to do the study.
| Been happening in economics forever too.
| BoredPositron wrote:
| ITT people that only read the headline.
| fHr wrote:
| 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.
| keeperofdakeys wrote:
| Reminds me of the story of Polywater.
| https://en.wikipedia.org/wiki/Polywater
| zahlman wrote:
| > a hypothesized polymerized form of water
|
| With what chemical structure, even? That should have been the
| first red flag.
| thomasgeelens wrote:
| 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?
| refulgentis wrote:
| It wasn't an oversight? They sighted it immediately, hunted it
| down, then wrote it up for you.
| zug_zug wrote:
| This is good news, probably. We'll have to wait and see which
| studies replicate and which don't.
| ErigmolCt wrote:
| Lots of signal, lots of noise, and slowly figuring out which is
| which
| dust42 wrote:
| So basically the gloves that kitchen staff now must wear means we
| get an extra dose of micro plastics? Yikes.
| firesteelrain wrote:
| It 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 wrote:
| I'm still not aware of any reason to worry about micro
| plastics. As far as I know they seem harmless?
| SapporoChris wrote:
| It 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 wrote:
| Is 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.
| wisty wrote:
| Yeah, they gum up cellular workings. Kind of like how
| macro plastics will gum up turtle stomaches.
|
| 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.
| kalaksi wrote:
| I get your point that plastics are relatively inert and
| may not cause noticeable harm (depending on quantity?),
| but I think it'd be wise to be cautious. See for example
| https://en.wikipedia.org/wiki/Plastic#Bisphenol_A_(BPA) .
|
| I'd also consider plastic, and their additives, to be a
| lot bigger and longer lasting unknown than GMOs.
| Lerc wrote:
| And indeed there is not currently conclusive proof that
| WiFi is a significant risk to human health. However, this
| is the same line the tobacco industry used for decades
| even though they knew different.
| timr wrote:
| Because it's an inverted claim of falsification it works
| for literally anything (I cannot prove that X will
| absolutely not hurt you), but you get pilloried if you
| put something in the blank that the herd happens to
| support.
|
| 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.
| SecretDreams wrote:
| I think any time a new material starts to meaningfully
| accumulate in our bodies, our food sources, our oceans,
| etc, we should at least go with caution. The default stance
| should be caution, not fearlessness.
| bluebarbet wrote:
| >fearlessness
|
| 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...
| SecretDreams wrote:
| Totally aligned.
| kalaksi wrote:
| Many negative health effects have been associated with
| microplastics and related chemicals. Not sure if there's
| yet anything causative, but I think it's probably a matter
| of time and there's lots of research to be done. I'd bet
| the health effect of microplastics (or anything that human
| body isn't used to) is more likely to be negative than not.
| schiffern wrote:
| The problem isn't just the plastics themselves. 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.
|
| 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/S03043894
| 2...
|
| 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.
| Lerc wrote:
| _> 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.
| titzer wrote:
| Synthetic fibers from clothes are microplastics, and
| clothes shed lots of fibers. Not to mention all the
| upholstered furniture, carpet, rugs, drapes, bags, etc.
| Lerc wrote:
| That's why I said
|
| _> 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.
| lstodd wrote:
| Dog, ha. Try a longhair cat. You'll be extracting balls
| of fur from most unexpected body cavities.
| fuzzfactor wrote:
| Instant corrective upvote.
|
| 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.
| sumea wrote:
| Stearates are considered very safe chemical compounds. They
| are derived from stearic acid which is one of the most common
| fatty acids and metal ions such as sodium and magnesium.
| Sodium stearate is a common soap and magnesium stearate is
| one of the most common additives in pharmaceuticals. This
| means that they are practically everywhere and but also
| easily digested in small amounts.
| johnbarron wrote:
| No: https://news.ycombinator.com/item?id=47563392
| daedrdev wrote:
| In the article it explains that what they release are not
| microplastics
| cogman10 wrote:
| Funnily, I believe the glove mandates for food prep are
| actually anti-hygiene.
|
| 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.
| tsunamifury wrote:
| Uh yea. That's why most places use washed hands not gloves.
|
| I've never seen for example sushi portrayed with anything but
| bare hands
| Panoramix wrote:
| Sushi chefs spend years learning the correct feel of the
| fish - when it's warm enough, when it's slimy. Japanese are
| taken aback when they are forced to wear gloves for
| "safety", which at least in that case is entirely counter
| productive.
| crazygringo wrote:
| > _So you are less likely to replace gloves when you should._
|
| 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.
| cogman10 wrote:
| > 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 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.
| g-b-r wrote:
| That's probably the places where people would never wash
| their hands either
| kelnos wrote:
| > _It 's more than just procedure or habit, your hands
| feel dirty and you want to wash that off._
|
| 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.
| cogman10 wrote:
| I agree that it's not reliable.
|
| 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.
| ceejayoz wrote:
| > I don't know why you think food service workers aren't
| constantly putting on new gloves...
|
| 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_.
| crazygringo wrote:
| Yeah, but then something tells me they wouldn't be
| washing their hands instead. Which is the comparison
| being made.
| energy123 wrote:
| Many food service workers don't use gloves and don't wash
| their hands after going to the toilet, from what I have
| observed.
| 0xffff2 wrote:
| > 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.
|
| 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.
| Eisenstein wrote:
| If you don't have time to change gloves how do you have
| time to wash your hands?
| ceejayoz wrote:
| It's much quicker to wash your hands.
|
| Gloves require your hands to be perfectly dry to put on
| effectively.
| crazygringo wrote:
| I don't have the slightest idea what you're talking
| about.
|
| 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.
| ceejayoz wrote:
| I do a medical procedure several times a week that
| requires gloves.
|
| 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.
| gamblor956 wrote:
| Food safety regulations in most states require that food
| workers replace gloves if they handle raw meat and switch
| to other foodstuffs.
|
| 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.
| crazygringo wrote:
| I mean, they don't require gloves to be replaced in those
| situations because there isn't a good safety reason to.
| There's zero reason to replace your gloves when switching
| from dicing green peppers for a salad to picking up raw
| chicken. Or similarly between customers if you're just
| handling food, and not a cash register or anything. It's
| not like you're touching the _customers_...
| bonoboTP wrote:
| Yes but most people find it icky and would complain,
| especially if it's visible behind the counter. Customer is
| king... I can also imagine it helps with legal liability,
| "but we were so careful, we even mandated gloves!"
| cogman10 wrote:
| Yeah, that's more the problem than anything else.
|
| 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.
| s0rce wrote:
| People also don't develop good habits and constantly touch
| their face with gloves. I worked with surgeons in the
| hospital and they would point this out. Equally important in
| a cleanroom.
| logifail wrote:
| > So basically the gloves that kitchen staff now must wear [..]
|
| Genuine question: we used to simply wash our hands well before
| preparing food.
|
| At what point did the wearing of disposable gloves become
| "better"?
| randycupertino wrote:
| It's not better, it's a lazy shortcut so they have to wash
| their hands less and don't feel gross touching raw meat.
| ErigmolCt wrote:
| How tricky the whole topic is
| s0rce wrote:
| The stearates aren't microplastics, they aren't polymers, but
| they have chemical/spectroscopic similarity that results in
| them confusing the microplastics assays.
| fuzzfactor wrote:
| The transparent disposable food-service gloves are usually
| polyethylene so I wouldn't think they would have the exact same
| false-positive result as the nitrile gloves. Microscopic
| particles of stearates are what's on these nitrile gloves, not
| actual polymer dust or excess abrasive losses.
|
| 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.
| Mordisquitos wrote:
| 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.
| p-e-w wrote:
| > 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 wrote:
| >> I'm amazed that wasn't taken into account!
|
| This was taken into account:
| https://news.ycombinator.com/item?id=47563392
| timr wrote:
| You 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 wrote:
| Luckily HN software developers, the foremost authority on
| literally every subject imaginable, are here to bless the
| world with their insights.
| bonoboTP wrote:
| I think there's an important distinction of smug better-
| knowing instances.
|
| "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.
| timr wrote:
| There's also the possibility that some of us actually,
| you know...have subject-matter expertise.
| refulgentis wrote:
| Doubtful, in your case, no?
|
| "Nanomolar" is a dissolved-species concentration unit. It
| doesn't apply to spectroscopic particle counting.
| timr wrote:
| Uh, yeah. I know what the word means. See my response to
| the other comment where you say the same thing.
| refulgentis wrote:
| Spiritual equivalent of a life sciences forum discovering
| memory safety, one person who wrote code for a bit saying
| they wrote a memory bug in C once, then someone clutching
| pearls about why all programmers irresponsibly write
| memory unsafe code given it has a global impact.
|
| 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)
| david-gpu wrote:
| _> Spiritual equivalent of a life sciences forum
| discovering memory safety, one person who wrote code for
| a bit saying they wrote a memory bug in C once, then
| someone clutching pearls about why programmers
| irresponsibly write memory unsafe code given it has a
| global impact._
|
| 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.
| refulgentis wrote:
| That's the analogy working as intended: the answer to
| "why do programmers still write memory-unsafe code" is
| the same shape as "why do microplastics researchers still
| wear gloves." The real answer is boring and full of
| tradeoffs. The HN thread version skips to indignation:
| "they never thought of contamination so ipso facto all
| the research is suspect"
|
| (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)
| peyton wrote:
| You're ignoring the article to grind your axe.
| refulgentis wrote:
| What do you mean? (Genuinely seems you replied to wrong
| comment to me. What axe? What's in the article that's
| been ignored?)
| Der_Einzige wrote:
| You joke, but given that SWE/AI researchers literally
| invented AI that does everything else for them and is
| often super-human at intelligence across most things, I
| would unironically prefer the opinion of the creator of
| such a system over most others for most things.
| hnlmorg wrote:
| I cooked a steak yesterday therefore I am an expert in
| biology.
|
| 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.
| kelseyfrog wrote:
| 'I disagree, therefore I am an expert in skepticism.' The
| sword cuts both ways.
| hnlmorg wrote:
| No it doesn't. What you're describing is an oxymoron.
| dahart wrote:
| Are more "controls" what is necessary here? The problem
| wasn't plastic contamination, it was the presence of
| stearates. Distinguishing between stearates and
| microplastics sounds like a classification problem, not a
| control problem.
|
| 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.
| timr wrote:
| Many papers in this field are missing obvious controls,
| but you're correct that controls alone are insufficient
| to solve this problem.
|
| 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.
| dahart wrote:
| You're still bringing up different issues than this
| article we are commenting on.
|
| > 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.
| njarboe wrote:
| Any scientific paper that does not document how things
| were done (methodologies) is basically worthless in the
| search for truth.
| dahart wrote:
| I agree completely. My point is that documenting
| methodology is standard practice, as is strict quality
| control, in the microplastics literature. I don't know
| what controls are missing according to GP, and we don't
| yet have references here to back up that claim. By and
| large I think researchers are aware of the difficulties
| measuring this stuff, and doing everything they can to
| ensure valid science.
| refulgentis wrote:
| Not OP, but:
|
| > "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/d5a
| y0180...
|
| [2] https://news.umich.edu/nitrile-and-latex-gloves-may-
| cause-ov...
| timr wrote:
| > 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.)
|
| _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.
| refulgentis wrote:
| > ...
|
| "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"
| userbinator wrote:
| Doesn't take an expert to see that fatty acids and
| hydrocarbon chains from the degradation of polyethylene
| look nearly the same.
| refulgentis wrote:
| Not sure what you mean or how it's related. If the idea
| is microplastics aren't actually a problem, I'm totally
| open to that. But "it's possible everyone involved is
| overrating it due to scientists seeing fatty acids or
| hydrocarbons and calling it plastic" needs a little more
| than anon assertion :)
| userbinator wrote:
| PE consists of very long hydrocarbon chains. It can
| degrade into shorter hydrocarbon chains. Fatty acids also
| have long hydrocarbon chains. The detection method for
| microplastics commonly involves pyrolysis, which breaks
| down polymers into smaller molecules. It's not hard to
| see that they'll end up looking nearly the same.
| johnbarron wrote:
| >> That doesn't mean that most of these plastic studies are
| doing the necessary controls
|
| That was never my argument. Read it again.
| Betelbuddy wrote:
| >>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
|
| What boggles the mind is you commenting on an article you
| clearly did not read...stating something that is not there...
| jvandrian wrote:
| The article starts with this:
|
| "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."
| tasuki wrote:
| So you're saying microplastics aren't a problem, because there's
| too much microplastics in gloves??
| kQq9oHeAz6wLLS wrote:
| I don't see anyone saying they aren't a problem.
| daedrdev wrote:
| If 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.
| nobodyandproud wrote:
| Finally some good news.
| creesch wrote:
| Good 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,"
| johnbarron wrote:
| 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.
| RobGR wrote:
| Why 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 ?
| ErigmolCt wrote:
| So the takeaway is: we've been accidentally adding
| "microplastics" with the very gloves we use to avoid
| contamination. That's almost poetic
| rflrob wrote:
| Stearates 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 wrote:
| "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 wrote:
| Yeah, where is their control sample without any substrate on
| the sampler?
| s0rce wrote:
| No substrate in the sampler means there would be nothing to
| test. Can't tell if you are joking.
| s0rce wrote:
| That 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 wrote:
| 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.
| legitster wrote:
| 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.
| userbinator wrote:
| I 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 wrote:
| 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
| EPWN3D wrote:
| 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.
| suzzer99 wrote:
| Peter 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.
| eigenspace wrote:
| So, 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.
| _DeadFred_ wrote:
| We aren't really looking. In the most well known case we were
| able to identify they were killing salmon because the salmon
| were dieing and worked back from that, not because some study
| led there first.
|
| https://www.ehn.org/toxic-tire-chemicals-threaten-salmon-
| as-...
| RobGR wrote:
| That is a case of a specific chemical in tires, not
| microplastics generally, or even rubber tire particles
| generally.
| kevinob11 wrote:
| Isn't [bad thing is happening] let's work backwards and
| find [difficult to find cause] a really solid approach?
| zahlman wrote:
| > and part of that humility should involve being cautious
| about introducing them to our bodies and environment.
|
| What does that look like today, pragmatically speaking?
| achenet wrote:
| asking, for all tasks shown to introduce large amounts of
| microplastics in our bodies and environment, "can we
| accomplish this task in a way that doesn't introduce
| microplastics in our bodies and environment"?
|
| 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.
| stinkbeetle wrote:
| Gourds were made from gourds back in the day. Or possibly
| ceramic.
| sophrosyne42 wrote:
| I agree very strongly with intellectual humility. I just wish
| the microplastic fear mongerers would also take that lesson.
| garte wrote:
| Look up on fish and the consequences of microplastics on water
| animals. From starvation to sex change, microplastics wreak
| havoc there.
|
| 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.
| orbital-decay wrote:
| Beware of the confirmation bias, it works both ways. Reporting
| might be alarmist (it always is), actual research is largely
| not. This study doesn't discredit the entire field, it's pretty
| obvious that microplastics are everywhere and different types
| are harmful to an unclear extent, even if the amount might be
| overestimated in some studies.
|
| _> 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.
| sophrosyne42 wrote:
| Unfortunately too often authors of non alarmist research end
| up promoting alarmist interpretations of their work in
| science media.
| Barbing wrote:
| I'll breathe tires a little easier today :)
|
| 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.
| calibas wrote:
| It was largely replaced with it's molecular analog, BPS.
|
| Just like BPA, BPS is an endocrine disruptor. The idea that
| it's less harmful than BPA is mostly due to lack of research.
| willrshansen wrote:
| Off the top of my head, wouldn't it be super easy to expose lab
| rats to microplastics and measure results?
|
| 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/...
| cowsandmilk wrote:
| > Even the authors of this study go to great pains to not
| challenge the dogma that microplastics are existentially
| terrifying.
|
| 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.
| userbinator wrote:
| One could say that all living beings are made of naturally
| occurring microplastics, long before humans even existed. After
| all, where else did that oil in the ground come from?
| AndrewKemendo wrote:
| 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...
| bluerooibos wrote:
| They found microplastics in the snow in Antarctica and in human
| embryos right? So this seems rather redundant.
| userbinator wrote:
| _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.
| fuzzfactor wrote:
| 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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