Basically, you've got an extremely sensitive measurement system being used to make tiny measurements, and then they extrapolate these measurements by a huge factor to get to ug/g estimates. Further extrapolating (to the weight of an organ, say) when you know that there's 25% inter-sample variation, is just guaranteed to be nonsense.
[1] https://www.nature.com/articles/s41591-024-03453-1
[2] "Both analytical laboratories (UNM and OSU) observed a ~25% within-sample coefficient of variation, which does not alter the conclusions regarding temporal trends or accumulation in brains relative to other tissues, given the magnitude of those effects."
Besides man-made plastics, guess what else has long hydrocarbon chains, occurs naturally in humans and other biological matter, and behaves similarly under pyrolysis...
https://en.wikipedia.org/wiki/Fatty_acid
Here's an interesting related article: https://www.oaepublish.com/articles/jeea.2022.04
Analysis of saturated, monounsaturated and polyunsaturated fats was demonstrated to form the same pyrolysis products as PE
Their response is not especially convincing, IMO, but they do at least discuss it.
The Smithsonian magazine article is garbage. Ignore it. The paper is saying that they see longitudinal trends in plastic bioaccumulation in various cadaver tissues, and this is plausible. But no, you don't have a plastic spoon in your head. That's just panic porn.
[1] Actually...I just asked Gemini and it reminded me that the expected variance of a draw from a distribution, scaled by factor C, should have a variance of the scaled sample distribution that grows with C^2. So, if we scale up the measurement by a factor of 10,000, we'd expect the variance of the scaled estimate to be proportional to 10,000^2.
You didn't expound upon your point about the unintended consequences of CAFE standards but they're very real. Instead of making smaller and more efficient sedans per the guidelines, car makers opted start making all of their vehicles "light trucks" -- 80%+ of new vehicles are SUVs or bubbly looking "crossovers" -- which are not subject to the same demanding standards. Small sedans also cost less and would require ongoing R&D to continue to meet the CAFE standards. The end result, as this thread is interested, is heavier vehicles with bigger tires and more plastic in the environment and our brains.
Paradoxically most of the 'small government' types are often the biggest road users.
Does this mean that a bus that weighs 10 times as much as a small car will produce 10000 times as much tire dust? If it does, I'm not sure if investing in buses will reduce tire dust at all. A bus can replace a lot of cars, but 10000 is a stretch. We need more trains.
Thinking about it a different way, there isn’t much difference in recommended tire pressure among the autos I’ve owned. That means that the pressure between the road and the tire is relatively constant but the surface area of contact is directly proportional to vehicle weight. For a fixed contact pressure, I am struggling to imagine a physical process by which the rubber loss is not proportional to the contact area.
Cheap, easy maintenance, good fuel economy and speed, traffic jam immunity..
If there's no regulation then there's no will or urgency to waste money doing so.
Saying a “spoon’s worth” seems to be downplaying the unmitigated potential risk. We have no idea what will happen as we (and all the other creatures on earth) keep storing more and more microplastics in our organs.
Nobody is going to stop driving. Car tires are the largest source of microplastics.
(actually I don’t drive though so who am I to judge)
The risk does seem fairly mitigated, most of us will make it through today fine. The only part of my brain I can account for now is the 1x credit card worth of plastic, all the other bits are a mystery. Death was inevitable before the microplastics, remains inevitable after the microplastics and things seem fine so far.
We don't know much about the risks of anything. People regularly douse themselves with mind-altering substances and ingest the weirdest variety of stuff.
And your philosophy of your own mortality is just as reductive, because humans have been trying to survive since time immemorial and do not actively work on their deaths unless in an unhealthy mental state.
This is an incorrect usage of the word "mitigate." To mitigate means to lessen the risk. Mitigation requires action.
I suspect you mean that the risks are "overstated."
If they're going for shock value they should use something more sinister than a spoon. Like enough plastic to make a little decorative Halloween spider. People would be more frightened by a spider than a spoonful of plastic.
many already have, bicycles and public transport ftw
oh
- Well, it's roughly the size of a two-year old child, if the child were liquefied.
How big is a spoon, anyway?
Well article says a teaspoon has 7g mass, and just spitballin here but I'd say a plastic spoon has about 1g/cm^3 density. And there are 4.83cm^3 in a teaspoon. So I guess in fact there are 1.44 teaspoons of teaspoon in the brain. Or would that be 1.44 tsp^2...?
But I'm an American and I have at least 3 imperial teaspoons of microplastic in my brain or gosh darnit I'm 2 bald eagles short of a touch down. If you know what I'm sayin.[1]
This assumes the presence of plastic is evenly distributed throughout the brain, which isn't necessarily the case.
Don't laugh, but I'm getting a new toothbrush to be safe.
> While we suspected that MNPs might accumulate in the body over a lifespan, the lack of correlation between total plastics and decedent age (P = 0.87 for brain data) does not support this (Supplementary Fig. 1). However, total mass concentration of plastics in the brains analyzed in this study increased by approximately 50% in the past 8 years. Thus, we postulate that the exponentially increasing environmental concentrations of MNPs2,14 may analogously increase internal maximal concentrations. Although there are few studies to draw on yet performed in mammals, in zebrafish exposed to constant concentrations, nanoplastic uptake increased to a stable plateau and cleared after exposure15; however, the maximal internal concentrations were increased proportionately with higher nanoplastic exposure concentrations. While clearance rates and elimination routes of MNPs from the brain remain uncharacterized, it is possible that an equilibrium—albeit variable between people—might occur between exposure, uptake and clearance, with environmental exposure concentrations ultimately determining the internal body burden.
Which means that if we were to take action on this, we might actually be able to reduce our exposure. Unfortunately, things are going in the wrong direction.
I keep thinking it would be nice if microplastic exposure were to start generating the kind of focus and controversy that is currently taking place with vaccines and autism spectrum disorder.
To anyone here that has made a deposit to the blood bank: we thank you.
As another commenter asked "How did the amount of brain microplastic manage to double between 2016 and 2025?" It is doubtful that the environmental concentration level doubled during this time.
And also may, or may not, be harmful.
I’m not a chemist, but it seems like if this can be done it would be huge.
I mean, assuming I do have a spoon's worth of microplastics in my brain, I don't notice any impairment.
I write JavaScript just fine.
We eat and breathe all sorts of stuff that comes in nano-sized particles. We've been inhaling smoke from cooking fire, eating plant matter crushed between rocks rubbing against each other, drinking water with dissolved bits of all sorts of things, and so forth for many millenia now.
The body seems to have mechanisms to clear most of this stuff out of us over time, no? Isn't our body chock-full of waste products from our cells that are constantly getting flushed out? Is there any reason to think that nanoplastics would be different?
Honest science on a foreign material in the brain or body should be able to present a baseline amount of total foreign material for comparison.
If our environment is now 10% microplastics, then 10% of the foreign material found in the brain being microplastics would be normal.
Okay I’m sorry for the snark but when these articles come up some are like “the studies are inconclusive of the effects” but I’m just like “there’s plastic in your brain!”
