There is growing evidence that there is much less to worry about on microplastics on several fronts.
1. A whole cohort of core studies have been judged to have invalid methodology due to not recording baseline microplastic levels (https://www.pnas.org/doi/10.1073/pnas.2411099121)
2. Young-onset cancers (especially colorectal cancer) which were inferred to be caused by a rise in microplastics are being linked explicitly to other mechanisms and cohorts. (https://ascopubs.org/doi/10.1200/JCO.2025.43.16_suppl.3619)
> A whole cohort of core studies have been judged to have invalid methodology due to not recording baseline microplastic levels (https://www.pnas.org/doi/10.1073/pnas.2411099121)
This does not say that and it's irresponsible to summarize it that way. That's a letter addressing a specific study from 2024 (which did record baseline levels because that's a standard experimental design step), arguing that it used an inadequate control so may have had background contamination when reporting the level of microplastics found in bottled water.
A "cohort of core studies" were not involved, and nothing was "judged to have invalid methodology". The study authors also replied, arguing that their choice of blanks was actually the better one: https://www.pnas.org/doi/10.1073/pnas.2415874121
There's been a slightly weird trend of people on HN that seem so eager to judge the microplastic story as overblown and unsupported that they're overstating and overextrapolating the smallest counter evidence into its own competing narrative, as if what we needed were more narratives. Resist this! That's not how good science or science communication is done.
I respectfully disagree, this was a commonly cited technique for measuring microplastics, which is why it calls into question many studies. Thanks for calling me weird :) I guess the suggestion though is I'm paid by big plastic or something, no infact I'm just a guy reading papers who is scared of death like everyone else.
> I respectfully disagree, this was a commonly cited technique for measuring microplastics, which is why it calls into question many studies.
What exactly was a commonly cited technique and where is this citation?
Regardless, you said "invalid methodology due to not recording baseline microplastic levels" when that was not the case and wasn't the letter's objection to the study's methodology.
> Thanks for calling me weird :) I guess the suggestion though is I'm paid by big plastic or something, no infact I'm just a guy reading papers who is scared of death like everyone else.
I said the trend was weird, but feel free to pick another adjective. Self contradictory, for instance. Sick of people overextrapolating from these "bombshell" microplastic papers, I will now overextrapolate from these "bombshell" methodological papers.
Look at the publications of the author of that letter and Cassandra Rauert, the lead author of the paper on detecting plastics in human blood that you linked below. Both of them have several publications on the almost universal contamination of the planet with microplastics and are clearly worried about the impact of this. Them insisting on and helping with better science from their colleagues is not laying the question to rest, it's a call to more rigorous action (literally[2]). It is scientific malpractice to call that "growing evidence that there is much less to worry about on microplastics".
[1] https://news.ycombinator.com/item?id=48133269
[2] https://www.nature.com/articles/d41586-025-00702-2
> There's been a slightly weird trend of people on HN that seem so eager to judge the microplastic story as overblown and unsupported that they're overstating and overextrapolating the smallest counter evidence into its own competing narrative, as if what we needed were more narratives. Resist this! That's not how good science or science communication is done.
This is completely true and well stated. However, this sort of rush to counter narrative is imo inevitable as a response the original rush to craft the narrative that we were all gonna die immediately micro plastics unless we did a Marxism right away.
I am deeply concerned for the environment of the Earth, I believe strongly that we should embed that concern into our economics (i.e. priced externalities, etc. ) so that we make a fewer bad decisions that pollute our nest.
However, I have sadly come to feel that many journalists who write about science, and perhaps even some scientists, see their role as activism toward a specific outcome rather than discovering and describing reality as it exists.
So while I agree, it’s not productive, I totally understanding the glee felt at the possible puncturing of the original narrative.
> However, I have sadly come to feel that many journalists who write about science, and perhaps even some scientists, see their role as activism toward a specific outcome rather than discovering and describing reality as it exists.
That's not a feeling, for journalism anyway it's an explicit fact. The Accrediting Council for Education in Journalism and Mass Communications (ACEJMC) - the primary agency that reviews and accredits journalism programs across the United States and whose mandates directly shape the curricula of over 100 universities - has changed their standards over the years away from emphasis on truth and towards emphasis on advocating change to institute certain policies. See https://www.acejmc.org/about/strategic-plan . They still mention truth, but almost tangentially among long lists of outcomes that journalists must pursue. The current generation of journalists were trained by these principles.
The Associated Press (AP) StyleBook https://www.apstylebook.com/ similarly polices the language that journalists use to favor certain policy outcomes, with some news organizations requiring compliance as a condition of employment.
But what exactly are you fighting for? What benefits are there to plastic food packaging, plastic kitchen utensils, kitchenware/food storage, clothing?
Plastic packaging made 20% of EU's total packaging waste in 2023 out of which 42% were recycled/downcycled. Personally plastic food packaging is the biggest portion of my family's waste output.
Plastic kitchen utensils like black plastic ladles are not durable (they break easily), and visibly degrade when exposed to heat or acidic food, unlike metal or wooden counterparts...
Plastic kitchenware and food storage containers are also considerably less durable than equivalent metal or glass products. They also stain and degrade when in contact with acidic or other specific foods...
I take it you've worn synthetic clothes, need I go into detail about how uncomfortable that is?
On top of that, most of these are tied with fossil fuel supply and prices, and you can see for yourself what's going on with that right now...
p.s. I'm pretty sure use of metal, glass, and wood is not marxism...
Those are all great reasons. What's the need to push for yet-to-be-subtantiated fears of microplastics?
What is OP fighting for? Idk, an unbiased view of reality, maybe?
My point is that limiting plastic use (especially single-use plastic) is a win in my book even if it is ultimately done for the wrong reason. Thus it's not worth my time going out of my way to disprove specific research that still ultimately points out the need to curtail plastic use...
What benefits? Single use plastics have one purpose and one purpose only: allow for fossil fuel producers to dispose of the ethane byproduct that accumulates during extraction. They get paid for the disposal vs having to process it as waste themselves.
I’ve never heard Marxism mentioned in the same sentence as microplastics. If you think advocating for a functioning EPA and regulatory control of manufacturing is Marxist then you’re just a straight up fool.
"Straight Up Fool"-ism is running rampant on HN
"Exercise induced gastrointestinal injury"!
Can't read the full study, but it seems to be specifically about people who run ultramarathons. Which sounds like a very small subset of the general population. I doubt that tiny cohort is in any way responsible for the overall increase in bowel cancer in younger people.
Actually this is the shocking part - it actually is enough to move the needle. Incidents of young people with cancer is small so a 100% increase can be driven by a small absolute number of patients. There has been an absolutely enormous increasing in high endurance sport something more like 20x (or 1900% increase) and ultramarathon/marathon runners are 7.5x more likely to get colon cancer, so this leads to a surprisingly large relative increase in colon cancer.
I think those papers mostly show that parts of the microplastics literature were overstated or methodologically weak, not that microplastics are harmless.
The PNAS paper is a pretty good critique of contamination/baseline issues, and I agree some of the “microplastics are causing young-onset cancer” claims got ahead of the evidence.
But the broader concern still exists: people are clearly exposed constantly, particles are being found in human tissue, and there are plausible mechanisms for harm. So no, there is not "much less to worry".
I agree that there is not evidence to "not worry", but many explicit worries are being accounted for.
Also - in terms of human tissue:
"The problem is that some small molecules in the fumes derived from polyethylene and PVC can also be produced from fats in human tissue. Human samples are “digested” with chemicals to remove tissue before analysis, but if some remains the result can be false positives for MNPs. Rauert’s paper lists 18 studies that did not include consideration of the risk of such false positives." (https://www.theguardian.com/environment/2026/jan/13/micropla...)
and Rauert's paper (https://pubs.acs.org/doi/10.1021/acs.est.4c12599)
“Young-onset cancers (especially colorectal cancer) which were inferred to be caused by a rise in microplastics are being linked explicitly to other mechanisms and cohorts.”
After which you link to a study showing that ultramarathon runners are at increased risk for colon cancer. Are you insane? This doesn’t refute the role of microplastics in any way shape or form. Do you know what % of the population with colon cancer are fucking ultramarathon runners?
I’m sorry but it’s impossible to tell whether you’re acting out of bad faith or are just a complete moron. Good God.
Fortunately however it's not hard to tell when people calling others "complete moron" are acting out of bad faith.
I don’t cooperate while others defect. I don’t subscribe to the marketplace of ideas or see any point in engaging in good faith with someone signaling bad faith.
A segment of the population has decided that they don’t care if economic growth comes at the price of health of ourselves or our environment. As far as I’m concerned, that is a declaration of war. An announcement of intent to carry out a mass genocide on their fellow human beings. There’s no point in debate. I just want them to know that we know what they’re up to.
Then don't reply.