8 ms·
Bioaccumulation of Microplastics in Decedent Human Brains
- giantg2 2y agoI thought it was difficult for many things to pass through the blood brain barrier. How are these particles making it through?
- MrVandemar 2y agoMy uninformed guess is the blood brain barrier is an evolved barrier that's very good at not letting things found in nature through, like various compounds, viruses, bacteria etc. We have no evolved defence against compounds and materials developed in the last century.
- notamy 2y agohttps://news.ycombinator.com/item?id=41316195 https://news.ycombinator.com/item?id=41316195
- giantg2 2y agoIs it just that any nanometer size particles make ot through, or is it just for select particles like plastic? Like if nanometer particles make it through, why do many drugs get blocked - are they just larger than a few nanometers (seems unlikely, but I don't know)?
- sickblastoise 2y agoWe’ve really screwed the pooch on this one. How many cancers, chronic diseases, birth defects, are a result of our mass pollution of this once pristine oasis of life, the only one we have?
- emeril 2y agoMaybe so, but think of the shareholders!!!
- Aurornis 2y agoBlaming shareholders is an easy cop out, but most people’s appetite for cheap plastic things is insatiable. It’s not like corporations are taking plastics out into the wilderness just for fun.
- jtdev 2y ago[dead]
- paulryanrogers 2y agoIndeed. Which is why we need collective action to overcome the power corporations have over an uneducated and apathetic population. A population they oversee through regulatory capture, advertising, curated studies, and (increasingly legalized) bribery of government officials.
- tirant 2y agoAre the microplastics found in the environment coming from corporations production residues or from people’s consumption residues ? I would say a relevant part of them comes from individuals. If you believe the issue is important enough, then raising awareness is the right direction so they take healthier choices. However most of the worlds population lives in developing countries, and microplastics are very low in their list of priorities, their top priority is actually making to the end of the month with enough food, shelter and some medical care or even education for them or their kids. Blaming everything on greedy corporations is a very superficial analysis.
- amanaplanacanal 2y agoIndividuals don’t make the plastic. It may come from post consumer waste, but it is manufactured by the corporations. Individual action is unlikely to make a dent in this issue.
- emeril 2y agoAgreed though I see the current situation as just yet another result of the inherent flaws in human reasoning where some significant percentage of the population can't reason sufficiently well to make reasonably optimal choices (e.g., conservative science denialism). This is why we, as a population, won't agree to curb CO2 sufficiently to address climate change but instead will simply adjust and, maybe eventually, accept geoengineering based approaches. That said, the next 10 years will be telling in how conservatives react to much higher home owner's insurance premiums...
- hammock 2y agoI’m wondering the same thing. What is the evidence they Microplastics are harmful?
- kragen 2y ago> The extent to which microplastics cause harm or toxicity is unclear, although recent studies associated MNP [micro- and nanoplastic] presence in carotid atheromas with increased inflammation and risk of future adverse cardiovascular events²⁻³. In controlled exposure studies, MNPs clearly enhance or drive toxic outcomes⁴⁻⁶. The mantra of the field of toxicology – “dose makes the poison” (Paracelsus) – renders such discoveries as easily anticipated; what is not clearly understood is the internal dose in humans.
- hammock 2y agoIn plain English? And is correlation causation or no?
- Rhapso 2y agoIn plain English: There exists a dosage that causes problems, we don't know what it is. If this trend continues, we will most likely find out what it is the painful way.
- deleted 2y ago[deleted]
- jfoutz 2y agoI'll take a stab at it, but I'm not a doctor or a biologist. Cyanide will kill you. Almonds have trace amounts of cyanide. You can eat almonds till you get sick, but that tiny amount of cyanide won't kill you. The dose makes the poison. On the other hand, those fancy car-fentanyl, if a flake touches your skin, you'll od and die. It's super super toxic. One flake of microplastics in your body isn't going to do anything. Now, > although recent studies associated MNP [micro- and nanoplastic] presence in carotid atheromas with increased inflammation and risk of future adverse cardiovascular events It's not like every muscle fires on every heartbeat. They try, but some are old or dead. There are a lot of them, all working together. And they're constantly repairing or regrowing new muscle cells. How does the heart shed microplastic? Can it? How much till the immune system kicks in and starts causing inflammation? Inflammation is generally good, but super dangerous in the heart. Too much inflammation, and well, it stops firing correctly. > what is not clearly understood is the internal dose in humans. How much microplastic is too much? nobody knows. Seems like, you get too much, and repair systems start kicking in. The repair systems can't actually fix anything, but make you weak/sick, and you're generally worse off. When some other thing shocks the system, your body is already in panic mode, so the "normal" response of panicking doesn't change anything. Odds are, you just die.
- ssnistfajen 2y agoIf microplastics are directly causing illnesses and birth defects then we would've found out already. Past cases of mass illness caused by pollutants (lead gasoline, asbestos, minamata disease, thalidomide, chimney sweep's carcinoma, etc.) were uncovered quickly and usually addressed not long after. The fact we still can't pinpoint exactly how microplastics are harming us beyond that they are in places where they are not supposed to be, The one reassuring thing about this whole ordeal is plastics are largely inert, that's why they take forever to degrade.
- chemicalnovae 2y agoI didn't go and look up the others but this argument by similarity, at least when applied to asbestos says the exact opposite to the claim you're trying to make. It's generally considered that industry/government was aware of the issues relating to asbestos in the '30s (and _started_ doing things about it then) but it wasn't until the 70's/80's (depending on the country) that its use was mostly stopped (and in places like Australia it wasn't outright banned until 2003).
- ssnistfajen 2y agoAnd? That span is within an individual's lifetime, which is not very long in the context of human history. As of now there's zero sign any entity with regulatory power is doing anything about microplastics. Also, why are you trying to deliver a point without looking up most of the examples I've listed? Do you expect that to be a convincing argument?
- paulryanrogers 2y agoEach of us only gets one life. If most of that time is spent being unnecessarily exposed to pollutants with adverse health effects, then we have good reason to be outraged. Consider also that some pollutants accumulate in the food chain, impacting future generations, for an indefinite time. Such as mercury in seafood.
- 2y ago
- dukeofdoom 2y agoThe world retarded backwards socially in the last decade, standard of living declined, lowered testosterone levels, lower sperm counts, lower fertility rates, and perhaps lower IQ. I suspected mass induced psychosis around Covid times. Now I suspect all the plastic people are consuming.
- roenxi 2y agoNature killed more people when the oasis was pristine. Life pre-plastic was shorter, more brutish and a lot less comfortable.
- HeatrayEnjoyer 2y agoWe can get rid of plastics without throwing out every medical and QoL invention...
- bamboozled 2y agoThis comment won't age well if we keep polluting the environment the way we are. Plastics will continue to grow as a problem if we keep using them at the scale we do.
- formvoltron 2y agowhat boggles the mind is that there doesn't seem to be any way to avoid absorbing this stuff. it's in the food, the air, the water. even if you try to filter the air or filter your water.. the filters are made from plastic!
- bamboozled 2y agoWe messed up. Monkeys with hand Grenades. Humans with plastics.
- fao_ 2y agotom lehrer seems appropriate right about now — https://www.youtube.com/watch?v=JPrAuF2f_oI https://www.youtube.com/watch?v=JPrAuF2f_oI
- in_vestor 2y agoThe paper shows 2024 brains are worse than 2016 brains. Why? It’s not that long, and it’s not like the decade prior to 2016 had less plastics.
- codytruscott 2y agoReasonably significant transition to PEX piping for domestic water supply starting in 2004 following a surge in copper pipe pricing.
- intelVISA 2y agoPhew, glad I only drink water ampoules.
- codytruscott 2y agoSeems like a reasonable possibility considering the notable jump in PE in the kidneys.
- CommieBobDole 2y agoThis makes me happy I have copper plumbing with nice, healthy 1970s lead solder.
- drekipus 2y agoMake sure it's organic, grass fed, lead solder
- Centigonal 2y agoJust guessing here, but I doubt PEX piping is a major contributor, seeing as it's solid plastic that doesn't shed and is rarely exposed to the elements. The most common sources of micro plastics appear to be things like synthetic fibers in clothing, particles coming off of car tires as they wear down, manufactured plastic particulate like micro-beads/glitter, and plastic objects in the ocean that break down into smaller and smaller pieces due to physical abrasion, sun, damage, etc.
- 2y ago
- samplatt 2y ago>The mean (and standard deviation) age of 2016 decedents was 50.0 (±11.4) years and 52.3 (±16.8) years for the 2024 decedents. 27 organ material samples from 2016 and 24 samples from 2024 - but they don't say if they're from different people. I assume they are but it's not stated. Just wondering how much the increased age would have contributed to differences between the two years.
- perching_aix 2y ago> The ubiquitous presence of plastics, especially polymer-derived particulates ranging from 500 micrometers in diameter down to 1 nanometer, defined as micro- and nanoplastics (MNP) Aren't plastics by design long chains of molecules? 1 nm is like a handful of atoms at most afaik. How small do plastics get?
- userbinator 2y agoYes, a carbon-carbon bond is around 0.1-0.2nm. At these scales, these "plastics" are closer to monomers than polymers. A 10-carbon chain with its hydrogens attached can hardly be called "polyethylene"; it is a higher alkane and behaves more like wax or mineral oil than what most people would call a plastic: https://en.wikipedia.org/wiki/Higher_alkanes https://en.wikipedia.org/wiki/Higher_alkanes I wonder if the PE they are finding is actually https://en.wikipedia.org/wiki/Petroleum_jelly https://en.wikipedia.org/wiki/Petroleum_jelly
- t-3 2y agoThey can still be long chains - the quote mentions diameter, not length.
- perching_aix 2y agoOhh, that's a good point. I wonder how tightly they pack.
- hammock 2y agoWhat is the evidence that Microplastics are harmful?
- notarealllama 2y agoFrom TFA The extent to which microplastics cause harm or toxicity is unclear, although recent studies associated MNP presence in carotid atheromas with increased inflammation and risk of future adverse cardiovascular events2,3. In controlled exposure studies, MNPs clearly enhance or drive toxic outcomes4–6. The mantra of the field of toxicology – “dose makes the poison” (Paracelsus) – renders such discoveries as easily anticipated; what is not clearly understood is the internal dose in humans.
- hammock 2y agoSo… we don’t know. Please take back your profanity and your downvote. An association means little considering Microplastics are more commonly found in garbage ultraprocessed food. And the second part of your quote is saying we can make anything toxic in a controlled exposure if we dose it high enough
- MVissers 2y agoDoc here. It’s hard to prove. You can’t do a double-blind randomized control trial. And we have barely learned to measure these nanoplastics. But there are starting to be strong correlations between the plastic occurrence and terrible diseases. Recent data on atherosclerosis + infarcts is horrible. Recent data on testes production of sperm cells also looks very damning. In summary, there are a few unexplained things in medicine that might very well be caused by plastics. Eg. More colon cancer in young people in the west. Eg. Declining sperm quality in the last 30 years in the west. Yes, it could be foods, but it doesn’t explain the whole picture. Plastics could be it. My guess is that a LOT of nasty studies will come out in the next years. I switched to glass and metal for all my food and water, for as much as I can control it.
- whatshisface 2y agoAnother thing you can do to limit your exposure is to move far away from high-traffic roads. Tire dust is a major factor in exposure.
- Abismith 2y ago[dead]
- true_blue 2y agoThe scariest part for me is that there's essentially no escape from microplastics. If it turns out that they're greatly harmful, what can you really do?
- userbinator 2y agoThey're obviously not, or we would've seen the effects by now (around a century of plastics in use.) Remember when RF was the boogeyman? Paranoia about microwave ovens and cellphones causing cancer and other illnesses?
- s__s 2y agoYes but the amount of plastic in use has increased dramatically. Also there’s evidence that the process of recycling plastic is what creates a lot of the problematic microplastics. We only very recently started recycling plastic.
- myth_drannon 2y agoGo live somewhere in Northern Canada
- nick__m 2y agoThe artic is already contaminated: https://www.nature.com/articles/s43017-022-00279-8 https://www.nature.com/articles/s43017-022-00279-8 Even the Antarctica is starting to see microplastics: https://www.smithsonianmag.com/smart-news/in-a-first-microplastics-are-found-in-fresh-antarctic-snow-180980264/ https://www.smithsonianmag.com/smart-news/in-a-first-micropl...
- myth_drannon 2y agoYes, of course, the whole planet is polluted. But I read that 80% of microplastics pollution comes from tires. If you can get away from the cities, you can almost be free from the majority of pollution.
- kragen 2y ago> Formalin-fixed tissue samples (approximately 500mg) were digested with 10% potassium hydroxide for 3d at 40°C with intermittent manual mixing to ensure even and thorough digestion. "you think your job is bad, kaitlyn? get a load of what dr. campen's got me doing this week!"
- deleted 2y ago[deleted]
- paulmd 2y agoOnly the Polytron reduces an entire mouse to a soup-like homogenate in 30 seconds. https://www.thomassci.com/Equipment/Homogenizers/_/Polytron-PT-1035-GT-Laboratory-Homogenizer https://www.thomassci.com/Equipment/Homogenizers/_/Polytron-...
- kragen 2y agommm, my favorite! but hold the potassium hydroxide this time, i'm going to need my esophagus later tonight. and go easy on the formalin
- Aurornis 2y ago> The brain samples, all derived from the frontal cortex, revealed substantially higher concentrations than liver or kidney, at 3,057 μg/g in 2016 samples and 4,806 μg/g (0.48%, by weight) in 2024 samples, ranging as high as 8,861 μg/g. Brains were 0.5% plastic by weight? The highest value was nearly 1% plastic. That seems hard to believe.
- matt123456789 2y agoThat’s actually great news - neuroplasticity turns out to increase as we age.
- Dr_Birdbrain 2y agoAngry upvote
- ashton314 2y agoBooo. Well done on the pun.
- dyauspitr 2y agoThat seems very unbelievable. A >1 inch ball of solid plastic in the brain? So essentially a solid plastic golf ball? How is it even getting to the brain- isn’t there a blood brain barrier that even pathogens have a hard time getting through?
- 2y ago
- makotech221 2y agoVery amusing that after decades of warnings about microplastics, there haven't been any studies to move beyond the point of 'maybe they cause issues'. We can all only assume that they do, of course, because any normal society not entirely captured by capital would allocate money to research this topic thoroughly. The fact that we haven't means that they know it causes issues but it would be costly to do cleanup.
- someotherperson 2y agoOr there is no big enough sample size to compare against. How do you even establish a baseline without a control group?
- userbinator 2y agohaven't been any studies to move beyond the point of 'maybe they cause issues'. People don't get any engagement and media sensationalism for finding no evidence. Now that society is biased towards that instead of truth, "maybe" is the best they can do.
- seuraughty 2y agoPeople are researching it, there is funding for it [1]. It’s a challenging thing to research. Is it microplastics or nanoplastics or both? How many types of plastic are there, half a dozen? What type of plastic do you want to test, what about multiple plastics in different proportions? It can be difficult to identify mechanisms behind adverse reactions to more obvious stressors, let alone something like this which appears more chronic, long-term, and insidious. 1. https://grants.nih.gov/grants/guide/notice-files/NOT-ES-23-002.html https://grants.nih.gov/grants/guide/notice-files/NOT-ES-23-0...
- Filligree 2y ago> How many types of plastic are there, half a dozen? Several dozen major ones, starting at cellulose. And before you think I'm missing the point: Well, no, cellulose didn't biodegrade for what IIRC several hundred million years. That's why there's no such coal. It still barely biodegrades.
- userbinator 2y agoThis is a preprint. It has not yet been peer reviewed by a journal.
- adriand 2y agoTerrifying study: “total plastics mass concentration in brains increased over 50% in the past 8 years”. Their 2024 brain matter samples are on average 0.48% plastic by weight, if I am reading this correctly: “The brain samples, all derived from the frontal cortex, revealed substantially higher concentrations than liver or kidney, at 3,057 μg/g in 2016 samples and 4,806 μg/g (0.48%, by weight) in 2024 samples, ranging as high as 8,861 μg/g.” The only good news is that apparently the brain can clear these particles; the problem is that there is a steadily increasing amount of exposure which means that rather than clearance, there is accumulation.
- timr 2y ago> Terrifying study Easy on the hyperbole. Let's assume that this study is correct, and everyone at median age of 50 is walking around with this level of microplastics in the stated organs. Are we all dead? Disabled? Dying? No. Our lifespans are amongst the longest in human history. I'm doing OK. How about you? Far bigger practical concerns are that we're fat and lethargic and suffering from metabolic disease, heart disease, cancer and diabetes en masse because we eat too much. About the only thing you can do with this finding is wave your hands around and make hypothetical links to this and that (as they do in the paper), or try to claim that this is really, secretly the underlying cause of the stuff that is actually, observably killing us. I'm not saying there's no concern here, but I am not "terrified" of this. I am actually scared of getting fat, or falling down when I get old from being weak. These are things that happen to nearly all of us. Anyway, first rule of science: when we look for things, we find things. If you are "terrified" by everything new you find, you are applying an emotional judgment to what you see, and not being objective enough.
- hombre_fatal 2y agoI have to agree. Making a big deal about microplastics when we’re overweight, sedentary, and atherosclerotic seems like stepping over dollars to look for pennies.
- cassianoleal 2y ago
- Sephr 2y ago> total plastics mass concentration in brains increased over 50% in the past 8 years I wonder if this correlates with the rise in the use of 'compostable' (i.e. weaker) plastics, that are more likely to break down during use.
- dukeofdoom 2y agoThis could be what caused the rise in Autism in Children. On the other hand, having grown up in a world where glass was used for everything. Cutting yourself on shard of glass from a glass bottle in the grass or alleyway was pretty common. Sometimes deadly when it cut a child's vain.
- frank_bb 2y ago[dead]
- tim333 2y agoI'm curious how they get in there. In food, through the gut then to the blood, then the organs? Or do we breathe them?
- Gin1982 2y agoAm I the only person that is skeptical about this papers findings? 0.5% just seems implausible to me. The study is preprint (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11100893/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11100893/) and it states that "The present data are derived from novel analytical chemistry methods that have yet to be widely adopted and refined" - "pyrolysis gas chromatography-mass spectrometry". This different paper talks about this approach and its limitations: https://www.mdpi.com/2673-8929/1/2/16 https://www.mdpi.com/2673-8929/1/2/16 "Prior to Pyr-GC/MS analysis, environmental samples undergo purification steps to isolate MP from the environmental matrix. However, this purification is not complete, and several organic and mineral constituents survive these treatment steps, especially in complex matrices such as sediments or soils. Hurley et al. [15] reported that the efficiency of removing organic matter from soil varied from 34% to 108% depending on the used reagent (H2O2, Fenton’s reagent, NaOH, KOH). These remaining particles will hamper the characterization and quantification of MP particles through Pyr-GC/MS. Upon thermal cracking, the polymers release pyrolysis products of lower molecular weight. Some of these products are defined as indicator compounds when they allow the detection of targeted polymers. However, some constituents of the remaining natural organic matter may release the same pyrolysis products as the targeted polymers [15,16,17,18], hence a potential MP overestimation. The identification of pyrolysis products that are specific to the targeted polymers is therefore necessary." Sounds like the detection methods and methodology for microplastics are evolving. It is plausible that the amounts are materially over estimated. Another thing that seems implausible is the increase between 2016 and 2024? "our finding that total plastics mass concentration in brains increased over 50% in the past 8 years.". 50% in 8 years! Is the world really that different in terms of plastic exposure 2024 vs. 2016. Unless something has fundamentally changed with the food supply in this period how can this be possible? Plastic production is increasing (https://www.statista.com/statistics/282732/global-production-of-plastics-since-1950/ https://www.statista.com/statistics/282732/global-production...) but for a 50% increase in this period something would have to have fundamentally changed with exposure routes in this period.
- throwaway657656 2y agoThe paper states the liver has 145 μg/g, about 30 times less than the brain but still a surprisingly high number. However, it is challenging to use that as a point of comparison. Would one expect the liver would have more than the brain because it is filtering blood, or less because it has mechanisms to prevent bioaccumulation ?
- deleted 2y ago[deleted]
- Ging1982 2y ago[dead]