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NikolaeVarius

I'm actually pleased that the article points out that we don't even know if eating microplastics even matter.

I totally expected it to default to the assumption that eating the plastic is by default harmful via magic

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Almost all plastic release chemicals having estrogenic activity [1] so not be default harmful, but probably harmful.

[1](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3222987/)

OTOH, all those chemicals are problematic precisely because they leach out into water. So you might expect marine microplastics to contain little-to-none EA chemicals, as they've been "cleaned" by the ocean for a long time.

I know that plastics leach chemicals into water, but I have never heard of "water cleaned" plastics no longer leaching chemicals.

It's also worth noting that consuming microplastics doesn't result in them being bathed in water, but rather our acidic digestive tract designed specifically for leaching chemicals out of things.

Worse yet, the plastics break down in water and plankton eat them up... and they're at the bottom of the food chain, not to mention phytoplankton produce between 50-85% of oxygen [0] and eat lots of CO2.

Disclosure: Involved in a project to raise awareness about plastic and noise pollution in the water [1].

[0]: https://thinkprogress.org/zooplankton-are-eating-plastic-and...

[1]: https://www.NoiseAquarium.com

I think only the stomach is acidic, and that bicarbonate ions produced by the pancreas and liver neutralise that acidity in the small intestine.

Your general point stands though: the particular water based solution in question serves a particularly important purpose!

yup - and some of these chemicals you certainly don't want leeching ...

Got a citation?

Even better, you could put your plastic where your mouth is and try a diet of washed microplastics every meal to see how it affects you. It’s not immoral if you do it to yourself!

Most plastics contain flame retardants. These compounds are known to cause health issues.

https://www.niehs.nih.gov/health/topics/agents/flame_retarda...

> I totally expected it to default to the assumption that eating the plastic is by default harmful via magic

I agree, as an optimist I believe that consuming inorganic compounds is by default healthy!

More seriously, I believe we should be very concerned about chemicals with unknown biological effects entering our food supply.

Say what you will about plastic, but it is definitely composed of organic molecules.

The main ingredient yes, but there is other stuff added to get specific properties.

https://www.plasticsintl.com/blog/what-are-the-ingredients-i...

Just like "metal" isn't 100% Fe atoms (or Cu or whatever the base metal or metals is/are).

I was not aware that the classification of organic/inorganic made any difference in the health value of a substance.

Salt itself is inorganic.

How could it be good? At best it’s probably neutral. But given our ancestors didn’t eat microplastics and our digestive systems evolved from them, I have a hard time imagining we’re able to digest microplastics well.

There are large economic and social costs incurred when people freak out about something common yet harmless.

True, but there are potentially much larger economic and social costs incurred when people remain oblivious of something that is harmful. Playing it safe is likely worth the cost, even if we pay for a lot of false positives along the way.

The entire point is that it doesn't matter if we eat micro plastics if we don't digest them in a way that matters. In the same way that I don't get iron poisoning by eating an iron bolt because my system can't process it.

The problem arises when your system treats it as something else. For example, how your system treats carbon monoxide like oxygen. Remember, we used to think things like lead-based sugars were fine to eat.

And, fwiw, your body would process a small amount of iron, since it's a mineral required for good health.

Why would you expect to not digest something you put in your digestive tract? You do, after all, digest part of that bolt.

Not everything that passes through the digestive tract is broken down and absorbed. A major portion of the food you eat is indigestible fiber.

If you were eating iron bolts with every salted meal I think you would find that it is not so harmless after all.

I would not advise eating foods containing iron bolts, though. This is what happens with the microplastics, they're everywhere now.

Micro iron bolts would be iron; an essential mineral.

Iron is also a toxin at doses above about 10mg/kg, so, yeah, if “micro iron bolts” were liberally distributed among common foodstuffs, that could be a real problem.

Too much of a lot of things (i.e. water poisoning, or too much vitamin A) are toxic.

The new study estimated that the average adult eats 2,000 microplastics per year. Heck, I probably eat more non-micro plastic (by mass) by accident in a year.

Particle scale almost certainly matters. Asbestos is, as I understand it, not particularly notable except for the size of the particles it tends to release into the air. Particles of sufficiently small size can be biologically active when the bulk material wouldn't be.

True, but is there anything known about this? The part of the thread (currently above this one) where people sum up the risks of plastics doesn't show anything that I'd say increases with lower particle size.

Ah the usual HN tecno-optimism.

1) The human body (and other lifeforms) evolved to adapt to substances found in the environment. That's why a number of synthetic substances are carcinogenic or otherwise toxic.

2) Microplastics contain a very wide variety of plastics. It's extremely unlikely that they are all healthy or neutral.

3) A number of types of plastic are known carcinogens and have been phased out.

4) Given this, he cautionary principle mandates to treat the as harmful by default, unless proven otherwise. There's a reason why drug and food approval processes exist.

What you see is just the precautionary principle. If MP's have rapidly found their way into the entire global food supply, there's a strong imperative to be concerned and figure out, quickly & in parallel, what can we do about it, how did it happen, and is it harmful.

No different than if a massive comet was hurtling towards earth. Yes, maybe it will be fine. But maybe we should be worried.

I would be very curious to know if there are naturally occurring polymers that create similar particles that we have already been living with.

Right, because the sane and objective assumption is that anything new we expose our bodies that hasn't been seen through the history of evolution is default safe until proven otherwise through decades of studies and counter-studies by entrenched capitalist interests. Yay progress!

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