What Do We Know About the Microplastics Inside Us?
140 points
2 hours ago
| 16 comments
| e360.yale.edu
| HN
AyanamiKaine
1 hour ago
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Microplastics have always fascinated me, because I keep seeing article after article about how much microplastic exists around us, but far less strong evidence about its actual effects. That is not to say there are no effects, of course. Maybe we just have not found them yet.

A friend of mine worked on her bachelor’s thesis about the effects of microplastics on the immune system, specifically T cells. Her result was that the microplastic particles she studied were too large to interact with T cells.

She probably will not publish this result because she thinks it is not interesting enough. Classic file-drawer problem in academic science.

While I encourage her to do it anyways as a negative results is also interesting but she wanted results that are worthing of headlines in magazines.

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legitster
55 minutes ago
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> She probably will not publish this result because she thinks it is not interesting enough. Classic file-drawer problem in academic science.

It's truly insane that everyone in the academic class understands the fundamental problems of herding and sampling bias and yet every incentive is in place to do this.

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etrautmann
42 minutes ago
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Having lived this reality, people respond to incentives. Your have to very fundamentally re-architect the incentives and career progression in academia to make publication of null results more common. The other side of this is reducing the time and hassle of publication. Right now I’m unlikely to battle for 1.5-3 years to get something through peer review for a result that nobody will find interesting.
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anonym29
1 minute ago
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>people respond to incentives

Careful, you're starting to sound dangerously close to an Austrian economist!

[ ;) ]

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zug_zug
27 minutes ago
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> but far less strong evidence about its actual effects.

Yeah, but we shouldn't take absence of evidence as evidence of absence. The fact is that it's just really really hard to establish a causal relationship, even if it's there, because of all the cofounders. Heck even if you constructed a study with a known poison, like lead, and you might not see the results in a single study. You could give 50 participants water with flint levels of lead in it for a month, and you might not get scientifically significant result just due to the wide variance in a population.

Or another example is just thinking how hard it would be construct a study with a control, when every single construction material has plastics in it and they are floating in the air around us all the time (as mentioned in the article). Could it affect mental or reproductive wellbeing? Certainly. Can we construct a study to establish either way? Not easily.

And one of the plasticizers they talk about, pthalates, are known to be endocrine disruptors (i.e. mess with hormones).

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marcosdumay
15 minutes ago
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> Yeah, but we shouldn't take absence of evidence as evidence of absence.

That's wrong. Yes, we should.

Each and every study that doesn't find evidence for what they are looking for is evidence for its absence.

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customguy
3 minutes ago
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Absence in the results of whatever we measured for. Just take the sheer hybris of "junk DNA": We don't understand this, so it's probably junk.
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unparagoned
7 minutes ago
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That’s wrong. Only if the studies are powerful enough and are looking at the right stuff can you make any reasonable conclusions.

If the studies are powerful enough then that absolutely isn’t evidence of absence at all.

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app13
1 hour ago
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I participated in research from 2017-2022 that found similar results regarding bio-interactions, generally.

Learned a lot about making microfludic flow cells at least

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jagged-chisel
1 hour ago
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> ... too large to interact with T cells.

Also, unfortunately, a result that industry and the anti-regulation crowd will use to say microplastics are harmless.

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w10-1
36 minutes ago
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also, asbestos is too small to interact with T-cells, so it must be safe.
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nostrademons
11 minutes ago
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It's not really analogous. One of the hypothesized ways that microplastics are harmful is that they disrupt the immune system; there has been evidence found of this in bivalves. Another is that they cause inflammation, which is also mediated by T-cells. A null result on the impact of microplastics on human T-cells is directly relevant to these hypotheses.

The mechanism of harm for asbestos is known to be that the fibers enter the lungs and can't be expelled, eventually leading to cancer. Its interaction with T-cells is quite irrelevant there.

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magicalist
46 minutes ago
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> Her result was that the microplastic particles she studied were too large to interact with T cells.

Her "result" of what? Was there an actual experiment and what was its scope or was this by surveying literature?

Microplastics are of a pretty large range of size, and then there are nanoplastics below that.

I'm also not an expert, but a quick search shows a number of results of microplastics affecting T cells, some directly and some in terms of immune signaling, so this negative result doesn't seem that definitive.

(as usual, the difficulty is in teasing out in vivo effects)

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vitally3643
26 minutes ago
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I'm not an expert but I'm going to condescend about an expert's "results" anyway.

Very informative, thank you for your comment. You have truly contributed to the conversation. Good job.

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NoImmatureAdHom
16 minutes ago
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She should at least put it on https://www.biorxiv.org/ !
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codybontecou
1 hour ago
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Can microplastics never get small enough to interact with T cells?
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Borg3
40 minutes ago
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Once microplastics fall apart futher, to nano-plastic, it will start to get absorbed by T cells because they want to destroy any invaders. Once absorbed, T-Cell start to produce H2O2 to destroy anything they absorbed. Unfortunately, plastics are mostly chemically neutral and so, it cannot be destroyed like that. T-Cells produce more H2O2, eventually it leaks outside and start inflamation of surrunding tissue. There is research about it.
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dzhiurgis
22 minutes ago
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AKA nanoplastic-induced oxidative stress, but it's actually macrophages (and neutrophils), not T-cells.

The reason this is problem is because cells can never destroy nano-plastic so they keep self destroying forever (chronic inflammation).

I still have my doubts about actual scale of this, especially how we still haven't solved pm2.5 pollution or even asbestos and heavy metals. And then there's PFAS, VOCs, Phthalates and Bisphenols. There's insane amounts of benzene in gas stations and traffic jam, yet no one really gives a fuck (until there's like a ppm in a sunscreen lol).

You are most likely to inhale it due to plastic abundance in environment, just like thousands of other things. It doesn't even have ICD yet. Ingested microplastic unlikely to breakdown while it travels thru your body.

p.s. my partner de-plastified a lot of my life (thru a lot of opposition of me) to the point where a lot of plastic objects feel gross now.

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Terr_
18 minutes ago
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> macrophages

Right, and when it comes to "what happens when the macrophage can't destroy what it engulfed", we can probably learn a lot from parallel work studying tattoos, where the ink-particles are similarly "attacked".

Plus it's a lot easier to create studies or even just observe the cells in question.

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Shog9
30 minutes ago
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Link to that research, please. It would add meaningfully to this discussion.
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Retric
58 minutes ago
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There’s a transition point where things stop being micro plastics and become chemicals. Those molecules may be toxic but the interactions are distinct from microplastics.
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tristor
52 minutes ago
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Unknown to me, but something useful to know is that there is something smaller than microplastics called nanoplastics. The distinguishing factor is that nanoplastics are particles smaller than 1 micron, while microplastics are particles between 1 micron and around 5 millimeters. As your other respondent notes, at some point you're talking about single molecules. As plastics is an entire category and not a single thing, there's no one size where that happens, but some polymers have chains that are as little as 0.01 (1/100th of a) micron in size.

As far as I am aware, we have yet to have effective, replicable research on what if any biointeractions exist with nanoplastic particles, including single polymer chains.

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schiffern
49 minutes ago
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I expect many researchers are using fresh lab-made microplastics, which are indeed mostly harmless. However part of the problem is that real-world plastics are chemical sponges that absorb toxins (heavy metals, PCBs, etc) from the environment and deliver them in a concentrated dose into the body.

https://www.eurekalert.org/news-releases/923529

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gruez
32 minutes ago
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>However part of the problem is that real-world plastics are chemical sponges that absorb toxins (heavy metals, PCBs, etc) from the environment and deliver them in a concentrated dose into the body.

>https://www.eurekalert.org/news-releases/923529

But your linked study only talks about biofilms and E.coli?

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wxw
1 hour ago
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Some stand out takeaways:

> We assessed how reliable current measures are for trying to find microplastics in blood. And what we found is that lipids and fats will give you a false positive for polyethylene.

> We worked with an architect, and we built the lab pretty much from scratch. [...] So we ended up going with stainless steel. It was the only way to not have any plastics.

> I don’t think we’ve got really good evidence at all for what effects [microplastics particles on their own] might be having on human bodies. If we’re eating plastics, what size and what type of plastic can actually get into the bloodstream?

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culi
1 hour ago
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This is a great interview, though I'd caution against reading it like a literature review. It's just the views and opinions of a single (relevant and qualified) expert
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odyssey7
40 minutes ago
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We don’t fully understand even some of the most obvious pathologies. If a disease isn’t glaringly obvious and coupled with profit incentive, God help you. The question of what microplastics do to us is simply beyond the capabilities of both modern medicine and academic research institutions.
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1970-01-01
37 minutes ago
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Would have loved to see the effects broken down by plastic, as the term "plastics" is as non-specific as "metals" and "organic"
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exactlyright
20 minutes ago
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Exactly. If you fart in a cup and then move it to your pelvis without letting any air leak out and then release it, that doesn’t count as a queef regardless of whether or not you had a vagina.

Words have meaning.

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billwirn
10 minutes ago
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I have lurked HN for about a year now, and just created an account to respond to this and say: ???
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mrkn1
40 minutes ago
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fwiw kimchi-derived probiotic bacterium (Leuconostoc mesenteroides CBA3656) was shown to bind nanoplastics and help mice excrete more of them. But it’s not yet proven that eating kimchi removes microplastics from humans
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mcmcmc
37 minutes ago
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It is proven that it tastes hella good though
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mrpeek
55 minutes ago
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We’re going to find out at an autopsy.
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zug_zug
31 minutes ago
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" We tested about 30 different construction materials trying to find some that didn’t contain plastics, but also didn’t contain plastic [additives] such as phthalates, but we couldn’t find any. Everything had either plastics or phthalates in them."
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radiusvector
1 hour ago
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Did she debunk that article that was around microplastics in human testicles?
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skyq
1 hour ago
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I have grown to accept it. It is part of me now
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andrenotgiant
1 hour ago
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I think hate of plastics is an emergent form of elitism.

Upwardly mobile middle/upper class people who've sort of "maxed out" the amount of personal identity they can buy with regular plastic things can unlock a new level of identity by deciding that plastics are bad for them and eliminating plastics from their life, a process which conveniently requires buying a whole new set of things that distinguish them from their peers.

This is the only way I can explain how irrational and inconsistent plastic-haters behavior is. There is so much invisible plastic in their life that they don't seem to care about.

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cobbzilla
1 hour ago
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> requires buying a whole new set of things that distinguish them from their peers

No, it requires buying a whole new set of things to fit in with and be accepted by their peers, to distinguish themselves from the outgroup, the plastic users.

I don’t necessarily believe this is some emergent elitism; I see it more as a modern religion with many many rules about eating and consumption (using plastic is now a sin).

Like any religion, sinners (for example plastic users) are mostly pitied because they are ignorant, but those who know and choose to use plastic anyway, well, it’s OK to hate them.

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beej71
48 minutes ago
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I don't get this whole attitude. Moving away from plastics in our kitchen was basically zero extra cost. Something busted, and we replaced it with non-plastic. Even bamboo scrubbers don't cost more than plastic (maybe even a little less) and I can't see any particular longevity difference.

I think the fact that I volunteer to clean up trash on public lands and know that weathered plastic is the period worst period to remove makes me move away from plastic in general.

Plus, a solid $3 wooden spoon is just a joy to cook with. They outlast the plastic ones, too.

Microplastic ingestion? Well, I'm not sure the effects or the relative quantity compared to tire shed and other industrial factors. But if I were forced by some diety to bet my life on if plastics in the kitchen or on clothing had a negative health effect, I'd make that bet.

But the main thing I don't get about the attitude stems from the fact that I don't really care what other people use in their kitchens. I recommend it.

Just please don't litter. :)

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topgrain2
27 minutes ago
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Things like glass food storage containers are really expensive compared to plastic. And they still have plastic lids; like, I don't know what you'd even do without at least the seal-part being some kind of plastic, I guess you'd need to use natural-sourced wax to make it seal, or something?

And on the topic of cost, I'm certain my kids have broken between 50 and 100 glass and ceramic drinking cups, storage containers, plates, and bowls in a little over a decade. They destroy plastic items at a way, way lower rate. Consider the use case of packing a kid's lunchbox. Plastic is... very tempting, for practical reasons. And cheaper.

Last I checked, plastic vs. wood on an otherwise identical stamped metal Victoronix knife costs you an extra $15-$20, which is a notable percentage of the total cost of the item. I sprung for the wood on my latest replacement just for the aesthetics, but it cost enough more that I did give it a good think first.

> Even bamboo scrubbers don't cost more than plastic (maybe even a little less) and I can't see any particular longevity difference.

Are those actually just bamboo? Maybe they are, I dunno, I can't recall seeing one. Lots of the "bamboo" materials I've encountered have turned out to contain (at least some) plastic.

> Plus, a solid $3 wooden spoon is just a joy to cook with. They outlast the plastic ones, too.

That's just true. Plastic spoons for cooking suck, wood and (where it makes sense and won't damage other things) metal are way better. Wooden ones aren't even expensive. The popularity of plastic ones is baffling.

One thing that's surprised me is the cost and/or total lack of availability of glass blender jars, even on fairly high-end brands (both the fake-high-end ones that are just expensive, and the actually-good ones). I remember my parents' assuredly cheapest-thing-in-the-store blender that they probably bought in the 70s or 80s had a glass jar, because that was just... standard. Meanwhile my as-awesome-as-I'd-hoped-thank-god expensive-ass Vitamix came with a plastic jar, and they do not make glass replacements. (I'm just checking and it looks like they might finally make one in stainless, though? Still, I'd prefer glass because being able to see what's going on in there is very nice, but I'm gonna have to look into that...)

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Apocryphon
50 minutes ago
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I've addressed this idea in a sibling comment. I think at least some superstition is inevitable in any subculture. Consider how many tech 'holy wars' might involve baseless beliefs about how a text editor or programming language or whatever being not only superior because of personal preference but because it's inherently more optimized. Treating anti-micro-plastics as a "religion" rather than a subculture based on a meme deserves a bit more nuance.

1. Is it based on inherently irrational, unfactual beliefs, e.g. like anti-vaccination or anti-5G myths?

2. If we consider religion as a way to explain complex phenomena using just-so stories (the pop anthropology / layman idea of primitive man inventing Zeus to explain lightning), then what intellectual or emotional need does anti-microplastics belief validate?

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dlcarrier
35 minutes ago
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Health in general has always worked like this, from supplements, to organic food, to avoiding ultra-processed foods, to gluten-free diets, pretty much every popular health fad has no provable causative effect on health.

Most of human behavior is irrational. If we were all perfectly rational, we would have healthy diet and exercise habits from the get go, and we'd have plenty of time to prepare food and exercise, because we wouldn't waste any time on entertainment.

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Apocryphon
58 minutes ago
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You could just liken it to any pop health, dietary, or environmental fad instead of trying to portray a banal "people turn consumer choices into personal identity/lifestyle" trend as a whole new class of phenomenon. Crunchy hippies shop organic and audiophiles buy gold-plated premium wires; every subculture has at least a little bit of superstition.
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ButlerianJihad
1 hour ago
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Even more so: plastics are not a specific chemical and they are not a specific material. Plastic is a category of materials that is very broad and very wide. You can make plastics out of almost anything. Therefore, to hate on plastics is to basically hate on an entire category of engineering and material design but not to actually know what a plastic is... sheer ignorance.
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estearum
49 minutes ago
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Yes, it's a category of materials that is overwhelmingly populated by a much more specific, ultra-cheap and therefore ultra-pervasive, set of chemicals which are shown in study after study to have worrying characteristics.

Anything that shows evidence of omnipresence, endocrine disruption, bioaccumulation, and inter-generational transmission should be extremely, extremely closely scrutinized.

To think otherwise is absolute braindead contrarianism, full-stop.

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ButlerianJihad
30 minutes ago
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Personally, I think that the Microplastics Moral Panic is a textbook study of F.U.D.

There is practically nothing that ordinary people can do for prevention, mitigation, diagnosis or treatment of microplastics in our bodies, so I therefore conclude that it is futile and wasteful to worry or argue about it, unless you have abundant free time and resources to get paranoid strangers all in a frenzy, for no good reason.

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topgrain2
18 minutes ago
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I half-assed try to avoid plastic in contact with (especially very) hot food or drink, and avoid it in long-term food containers, in no small part because I've seen things like plastic cooking spoons losing non-microscopic parts of themselves in food, and I find the stains plastic storage containers acquire after a little use kinda worrisome (I'd rather my reusable storage containers not be that permeable, thank you very much), but otherwise agree that any real amount of effort to avoid microplastics would probably do more good if it took the form of a 20-minute jog per week, i.e. "don't even consider worrying about it unless you've really, really got all your other health stuff sorted out"

Like I'm pretty sure the bigger health risk with a plastic soda straw is the soda, not the straw, you know?

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estearum
21 minutes ago
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Did this apply to people freaking out about lead a couple decades ago?

What about those advocating for smoking bans in shared spaces?

Cholera outbreaks near the city water wells?

Or are microplastics special in some way?

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globular-toast
42 minutes ago
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Are you sure it's all irrational? I, for one, prefer other materials for many things because they are more durable, hygenic or simply feels nicer. Seems perfectly rational to me. An irrational choice would be something like carrying a heavy canvas tent with wooden poles just because you hate plastic. Do you know anyone who does that?
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estearum
53 minutes ago
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> There is so much invisible plastic in their life that they don't seem to care about.

Huh? You think it's hypocritical for people not to "seem to care about" things that, by your own definition, they are ignorant of?

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Der_Einzige
1 hour ago
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Every plastic object replaced with a metal, or similarly strong/more solid material is an upgrade.
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The_Blade
1 hour ago
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one word: microplastics
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pohl
47 minutes ago
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deep cut
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MarkusQ
1 hour ago
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Very nice to see someone actually looking at the issue objectively instead of the unholy blend of clickbait, shoddy "science" and either fear mongering or blind denialism we usually see.

Getting to the point where we're actually able to measure something real is good progress.

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danteocualesjr
1 hour ago
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we have recently transitioned to only using glass bottles in our family.
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tantalor
1 hour ago
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tldr, not much because we can't measure it to begin with
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Agrue8u
1 hour ago
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did read, >e360: Do we really eat a credit card’s worth of plastic each week? >Rauert: That has absolutely been debunked

and >...we found is that lipids and fats will give you a false positive for polyethylene. Lipids are made up of the same building blocks as polyethylene, so when we analyze them, they look identical in our analysis instrument. >I know it is easy to say we don’t have enough information yet, but we do know about [the health risks from] these chemicals that are in all the plastics that your food is wrapped in.

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culi
1 hour ago
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Not just because we can't measure it but because its hard to say what's due to the plastic and what's due to additives in the plastics

> And while we know a lot about the impact of chemicals added to plastic — such as phthalates, which have been shown to impact fertility, or bisphenols, which have been linked to Type 2 diabetes — we know very little about what effect the plastic particles themselves might be having.

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1970-01-01
33 minutes ago
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>Even when you put a glass panel in the window, you have silicon holding the glass in. We tested all these different brands of silicon to try to find ones that had low levels of phthalates. It was a crazy amount of detail that we went to, but it was really worth it.

Silicone holds the glass panel. Silicon is the glass itself. Yale editors, do your job. She worked "a crazy amount of details", and so can you!

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godwinson__4-8
1 hour ago
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Are the microplastics in the room with us now?
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ChrisClark
1 hour ago
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yes
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ButlerianJihad
1 hour ago
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Please show us on the doll where the microplastics hurt you, for the jury please.
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mythrwy
49 minutes ago
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The doll is missing that part!
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