[HN Gopher] Nanoplastics promote conditions for Parkinson's acro...
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Nanoplastics promote conditions for Parkinson's across various lab
models
Author : ulrischa
Score : 110 points
Date : 2023-11-18 18:45 UTC (4 hours ago)
(HTM) web link (corporate.dukehealth.org)
(TXT) w3m dump (corporate.dukehealth.org)
| hapulala89 wrote:
| I think there needs to be more studies in the field of
| nanoplastics. They are nearly everywhere and all man made.
| freshnode wrote:
| I've been thinking about this potential link for a while.
|
| It would be interesting to see what relationship exists with
| allergies here as well, which are also becoming more prevalent
| for reasons we don't yet understand.
| Eisenstein wrote:
| Everything about micro/nano-plastic strikes me as another 'cell
| phones give you brain cancer' panic. There is no evidence that
| these things cause damage in mammals despite all the alarming
| research, and every headline leads to a 'more research is needed
| because this is scary' conclusion.
|
| Haven't we learned by now that if journalists are using scary
| headlines it is because they have nothing better to report, and
| if studies are concluded with 'we need to look into this more
| because data is scary' it means they didn't have anything better
| to conclude?
|
| Let's all calm down and wait for the other shoe to drop, if it
| does, and in the meantime communicate the message: 'these scares
| happen every decade, it is nothing new and we are still around,
| let's wait for some evidence before we panic'.
|
| And take this opportunity to say 'enough' to single use plastics
| when there are better options. It is absurd that we let it get
| this far. Let's go back to glass for liquids at least, and get
| rid of the 'wrap everything in a layer of plastic' tendencies
| that are completely unnecessary.
| shortcake27 wrote:
| > and get rid of the 'wrap everything in a layer of plastic'
| tendencies that are completely unnecessary.
|
| If only fruits and vegetables had robust, natural, bio-
| degradable packaging of their own. Some sort of peelable skin,
| perhaps.
| hutzlibu wrote:
| "bio-degradable packaging"
|
| That is the thing: they rot. And if wrapped in plastic, they
| last longer ... so more fruit makes it to the markets. That
| being said, I strongly prefer fruits directly from trees that
| were not treated with 50+ different chemicals.
| hammock wrote:
| >There is no evidence that these things cause damage in mammals
| despite all the alarming research
|
| There is no evidence despite all the research evidence?
|
| Or do you mean, there is more evidence that cell phones do not
| cause harm, than there is that they do cause harm?
| Eisenstein wrote:
| > There is no evidence despite all the research evidence?
|
| I am confused. Why are you talking about cell phones?
| shortcake27 wrote:
| There is no conclusive evidence. IE it has neither been
| proved in a lab nor observed in the population. Also, there
| is no known mechanism by which they could cause harm.
|
| I don't know why the burden of proof is so difficult for
| people to understand. If you make a claim, the onus is on you
| to prove it, not for others to disprove it.
| scottLobster wrote:
| And the "scares" are often correct. See smoking, leaded
| gasoline, trans fats, various other food additives, etc.
|
| You don't need a double blind study to look at smoking and say
| "inhaling smoke is probably bad for you". Likewise you can look
| at the evidence of microplastics being bad for human health and
| say "ingesting random synthetic chemicals that bio-accumulate
| and are hard to break down are probably bad for you".
|
| Obviously panic isn't helpful. But I've switched anything that
| has to touch hot food/liquid to some combination of
| glass/metal. I've also started buying milk in glass containers.
| All of this has had zero impact on my life beyond some upfront
| cost buying glass food storage containers and making milk more
| expensive. I'd recommend everyone else who can afford it do the
| same.
|
| Even in the 1950s when everyone smoked everywhere and you
| couldn't escape second hand smoke outside of the house, it was
| still a healthier choice to not smoke yourself.
| userbinator wrote:
| _Let 's go back to glass for liquids at least_
|
| Heavier, easily breakable, and far more expensive to process?
| hutzlibu wrote:
| You forgot reusable.
| jtrn wrote:
| I am extremely skeptical about this research. Firstly, the
| "plastic is bad" narrative is too easy to believe, just because
| plastic is ugly. It's also starting to follow the pattern I have
| seen in clinical psychology, where many studies find promising
| initial results, but no one bothers to conduct the real-life
| randomized controlled study that shows an actual clinical effect.
| And after a couple of decades of dogma, someone points out that
| the emperor has no clothes. Suddenly, the whole field looks
| silly, be it EMDR, classical psychotherapy, mindfulness therapy
| for severe mental illness, or the abuse craze in the 1990s.
|
| The longer it goes without concrete and clinically significant
| findings, the larger I think the probability of the findings
| being wrong becomes. I also find it strange that so few of the
| studies I have read ever comment on the fact that our system
| might be fully capable of removing the nanoparticles by itself,
| just as it removes everything from dust to methylmercury. We do
| not know if this is the case, but the fact that nobody is
| addressing this further strengthens my fear that there is a lot
| of confirmation bias going on.
|
| Every time I post something like this, I get a lot of angry
| responses, so I can try to preempt some of them by saying: I am
| not asserting that microplastics are safe. But the pattern of
| lots of pilot studies, and few studies that significantly prove
| the theory, is very recognizable to me.
|
| Until someone either conducts a naturalistic experiment with lots
| of people exposed to large doses of microplastics and compares
| them to a control group, or we expose some larger animals to
| microplastics over a long time in a true randomized controlled
| study, I'm going to remain skeptical.
| corethree wrote:
| Agreed but. Caveat here is that despite remaining skeptical we
| should still heavily pursue the idea as a possibility. We
| should not pursue this idea as if it was dogma.
| marcosdumay wrote:
| If a lot of people heavily pursue the idea without doing any
| conclusive study, you'll have lots and lots of positive non-
| conclusive results to publish on any hypothesis, it doesn't
| matter if it's true or not.
| corethree wrote:
| By pursue as a possibility I mean try to get a conclusive
| result.
|
| What you are describing here is "pursue as dogma"
| stevenwoo wrote:
| They did a comparison with graphene particles of the same
| size and they were neutral to the biological structure in
| question, only polystyrene of that size would bind to
| interfere with normal cell function in vitro and mice.
| Sparkyte wrote:
| This would be treating a hypothesis as fact. That isn't
| scientific enough, it would be good to isolate a demographic
| where plastics are least used and a demographic where
| plastics are highly used with similar populations. Try to
| remove or invalidate external effects or properties and
| calculate the health of the individuals. Health not just
| alzhimers, because everyone varies differently. This would be
| almost an impossible task.
|
| I'm sure there are more scientific ways to do a study.
| corethree wrote:
| No. I'm not saying this either. I'm saying with some
| evidence it's worth investing more money into causative
| experiments. This study is that "some" evidence.
|
| That means double blind experiments. Your correlative
| studies don't offer enough evidence. Causation is our
| strongest scientific metric.
|
| Human causative experiments are worth it as well in my mind
| with paid volunteers who are aware of the risk. But the
| legal barriers here are likely high.
|
| We can start with chimpanzees.
| swatcoder wrote:
| You're right that conclusive research can be impractical or
| neglected for many environmental and social impact "sciences".
| This is why psychology, ecology, biology, medicine and even
| chemistry weren't always taken seriously by more rigorous
| disciplines. No innovation really marked a moment between when
| they were denigrated as soft sciences that couldn't make sound
| conclusions and their role in society today. It's mostly just a
| cultural shift and a loss of implicit skepticism in them. So
| yeah, it's hard to _know_ stuff like "how dangerous are
| plastics" as rigorously as "how much energy is released when
| these two nuclei fuse"
|
| But there's also a practical weight that matters in a lot of
| these pursuits. Plastics overtook the world during a time when
| people weren't really considering their impact at ecological
| scale and didn't have sufficient models and tools to really
| assess what they might do to biological systems over lifetimes
| or generations. It was a historical accident that happened fast
| and without many brakes applied and now "plastics everywhere"
| is a pervasive background noise that's very hard to
| meaningfully control against. So the controlled science which
| was never conducted initially, and we now think probably should
| have been, is almost impossible to perform because we're left
| in that that fuzzy "soft sciences" place where everything is
| already plasticked.
|
| But does that mean we should just keep charging ahead without
| trying to look, and that maybe a mindful step back from
| unscientific historical use would be worth considering even
| without conclusive evidence (since such evidence is now too
| hard to gather)?
| pardoned_turkey wrote:
| You're cherry-picking plastics here. The same can be said
| about just about any technology developed in the past 200
| years, so what makes plastics special? We laugh at people who
| talk about the "precautionary principle" for vaccines or
| cling onto dubious research that purports to show some ill
| effects. Or, how about applying the precautionary principle
| to air travel - after all, do we really know the effects on
| your body of frequently changing timezones?
|
| We've been using plastics for a long time. They improved the
| world in important ways. There's nothing we can detect in
| large-scale studies of industry workers or other exposed
| groups that would suggest they're dangerous. That's kind of
| it. Every story you see on HN about microplastics is hand-
| wavy and involves dubious assertions and hypotheticals, and
| the alternative is... what? That we go back to making all
| commodity items out of metal, with a more serious
| environmental impact, higher transportation costs, and so on?
|
| There are wasteful uses of plastic which should be curtailed,
| e.g. for packaging fresh produce - but the concern here isn't
| microplastics, just pointless trash.
| jtrn wrote:
| I am sorry, but I am not able to connect with what you are
| saying.
|
| Many technologies have been studied properly and been found
| to be safe or unsafe. Smoking, non-ionizing radiation,
| airbags, alcohol consumption, exercise, beta-blockers,
| metformin, GLP-1, antipsychotics--all of these have been
| well studied and have been found to be clinically, not just
| statistically, relevant with regards to safety. Even
| vaccines are much better studied and understood with regard
| to risk compared to microplastics. So, I don't think I am
| just randomly picking on plastic research. I am holding it
| up as an example of research areas that are triggering
| skeptical red flags, as opposed to research that isn't
| stuck in the speculative phase.
|
| I also wasn't commenting on the issue of overproduction of
| goods, which I have thought about, but that is not what I
| was focusing on here.
| hammock wrote:
| >Until someone either conducts a naturalistic experiment with
| lots of people exposed to large doses of microplastics and
| compares them to a control group, or we expose some larger
| animals to microplastics over a long time in a true randomized
| controlled study, I'm going to remain skeptical.
|
| I know an anti-vaxxer who says the same thing about lifesaving
| vaccines, but in the opposite direction. He seems to claim that
| there are few/no truly inert (meaning pure saline, as opposed
| to aluminum-doped adjuvant without the inactive virus) placebo
| controlled RCTs for many of the most commonly scheduled
| vaccines. And until there is one, he won't believe they are
| safe.
|
| The guy is nuts imo
| jtrn wrote:
| I find that people who say "we need real-life practical
| studies" often have a viewpoint 180 degrees opposite to mine
| regarding research. They become annoyed when RCT (randomized
| controlled trials) studies prove that homeopathy or
| acupuncture doesn't work. They want to conduct "practical"
| studies with less rigorous design protocols. I want the
| opposite: I just want an RCT with clinically significant
| outcomes reported clearly (for example, a tenfold increase in
| microplastic consumption raised the prevalence of Parkinson's
| from 2 to 4 percent in the research group).
|
| The usual response I get is something like, "that kind of
| research is really hard to do." My response to that is,
| "conducting just easy research is not only unhelpful but
| actually detrimental to the field."
| Sparkyte wrote:
| Even with microplastics, other microscopic things entered food
| and consumption too. So I am skeptic, but the world also
| greatly benefits from the use of plastics in medicine. The rate
| of Alzhimers is not increasing, which would say elements of the
| disease not all microparticles.
| photochemsyn wrote:
| 'Plastic is bad' is indeed a gross generalization as plastics
| are made from a wide variety of monomeric units that are linked
| into chains or sheets to generate the final product. This
| article is specifically about polystyrene, which consists of
| aromatic (benzene ring) monomers. These are more likely to have
| biological effects, although of course there are aromatic amino
| acids, but there's also bisphenol A, a problematic additive.
| However, the specific evidence is worth looking at:
|
| > "Researchers said the plastic[polystyrene]-protein
| accumulations happened across three different models performed
| in the study - in test tubes, cultured neurons, and mouse
| models of Parkinson's disease. West said questions remain about
| how such interactions might be happening within humans and
| whether the type of plastic might play a role."
|
| Another thing to keep in mind is that Parkinson's appears to
| have a whole lot of different causes or risk factors, which
| accumulate as we age, from genetics to exposure to
| organophosphorous pesticides and this is just one more added to
| the list (wiki):
|
| > "PD is believed to begin principally by degeneration of
| dopaminergic nigrostriatal neurons in the brain and secondarily
| by complex pathological mechanisms, including mitochondrial
| dysfunction, oxidative stress, apoptotic cell death, protein
| aggregation and misfolding, inflammation, excitotoxicity, loss
| of trophic factors, and other cell-death pathways"
|
| So, it's not about 'plastics' in general, it's just that there
| are specific types and additives that should probably be phased
| out.
| grecy wrote:
| I think it's healthy to be skeptical, but also it's good to
| trust your gut and use some common sense.
|
| Plastic is made from refined natural gas and crude oil. We know
| for a fact those things are carcinogenic. There is no universe
| where putting them inside your body is not bad, and we should
| be doing everything we can to reduce it.
|
| > _a naturalistic experiment with lots of people exposed to
| large doses of microplastics_
|
| Are you volunteering to be in that group? Why not?
| fnordpiglet wrote:
| A few points,
|
| Plastic nanoparticles isn't a single thing. There are many
| types of plastics, with many types of additives. Most plastics
| are bioreactive, especially when not handled properly or
| maintained in the proper conditions. A great many plastics and
| especially additives are known to be toxic, carcinogenic, etc.
| These aren't controversial statements and is widely known,
| understood, and cataloged.
|
| Further, in this study, they point to prior studies that have
| established most adult humans have detectable amounts of
| nanoplastics in the blood stream. Further the point to prior
| research establishing many nanoplastics (and specially
| polystyrene, what they are studying here), passes the blood
| brain barrier.
|
| They contribute findings that, in mice, polystyrene
| nanoparticles are admitted to neurons and they isolate a number
| of changes in the proteins and signaling of the cells that
| propagate to other parts of the brain. The changes are
| indicative of changes observed in Parkinson's, but since we
| don't understand Parkinson's, we clearly can't establish a
| causal link in this way.
|
| RCTs could establish a probable correlate, but given again
| plastic nanoparticles are a single monolithic thing, there's an
| incredible amount of variability in such a trial. This will
| take a lot of time and need to be pretty narrowly constructed
| so fundamental research like this is how you establish and
| guide such trials in the future. We haven't really focused on
| the subject very long. But all of the facts above _should_ be
| of grave concern.
|
| Even if the body clears out nanoparticles, which I'm certain it
| must, that doesn't mean they can't cause serious issues prior
| to clearance. We are also presumably constantly exposed to more
| so you should view it as a chronic and persistent level in the
| body even if the body can clear it. In fact I would say unlike
| heavy metals we almost certainly clear it otherwise you would
| simply accumulate greater and greater concentrations; which I
| don't think is observed.
|
| It's good to be skeptical, but I don't think "we haven't
| established a specific disease caused by the pervasive presence
| of plastic nanoparticles in animals" doesn't imply "this is ok"
| by any measure.
| jtrn wrote:
| But you do agree that it would be better if we got some
| studies that went beyond "particles have been observed in
| tissue" to something like "This is the dose-to-morbidity
| curve for this group of nanoparticles"?My issue is that we
| have been stuck with hundreds, if not thousands, of research
| papers of the first type, and I haven't found any of the
| latter type.
|
| With regard to your last point, I kind of agree, but there
| has to be a balance between two extremes. You can't assume
| something is safe just because you don't have a smoking gun.
| On the other hand, the "you can't prove it's 100% safe for
| everybody at all times throughout the universe, so we must
| assume it's dangerous" position can also be very dangerous.
| To me, the anti-GMO movement makes this mistake in a serio
|
| us way, hurting actual people in deprived parts of the world.
| I fear that the microplastic scare is overblown and takes
| focus away from much more important issues.
| xyst wrote:
| > compares them to a control group
|
| Good luck finding a single person on earth (let alone, a group)
| not exposed to microplastics.
|
| The "forever chemicals" were found in even the most remote
| areas of the world. Wind, rain, storms, and other natural
| events carry this junk and spread it all over the world.
|
| There is literally a massive plastic graveyard in the ocean.
| Plastics turning into micro/nano plastics. Infiltrating food
| (fish), water, and carried into populations.
| beowulfey wrote:
| This is a molecular study. Not done in humans. It is showing
| the molecular effects of nanoplastics within cells. Does not
| claim anything about effects in humans directly, just provides
| a model for future testing.
| dehrmann wrote:
| The other thing that makes me skeptical is some things
| (asbestos, lead, DDT) turned out to be very obviously bad.
| There's the same level of panic with plastics (and not just
| microplastics), but not the same amount of evidence.
| wcoenen wrote:
| I had trouble finding the actual paper, but I think this is a
| preprint:
|
| https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10602106/
| Sparkyte wrote:
| I'll wait for this to be TLDR'ed through ChatGPT. It uses a lot
| of high speak, it seems to conclude that nano-particles not
| just plastics have an effect on proximity to neurons under the
| right conditions.
| beowulfey wrote:
| Here's the version in Science Advances:
| https://www.science.org/doi/10.1126/sciadv.adi8716
| CyberDildonics wrote:
| Are nanoplastics worse than microplastics? Will picoplastics be
| even worse?
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