Let me give you the argument, to see if you buy it. (Read Post #1941 and Post #1942 to see where I’m coming from on this issue.)
1: We’ve been using plastic, including artificial fibers, in the U.S., for a long time. 2: Therefore, best guess, whatever microplastic does to humans, it has already done that to us. Plus, 3: personally, as it turns out, I live in a microplastic-fiber-rich environment. I think.
Regarding that last point: The wall-to-wall carpet that came with my house is polyester fiber. Not only do I walk around on the cut-off ends of pieces of artificial-fiber yarn whenever I change locations within my home, the fiber is polyester, which typically gets fingered as potentially harmful microplastic.
My guess is that this surely (surely!) generates a microplastic-fiber-fragment-rich living environment. (But to be clear, there’s only a bit of research to support that, as outlined in this reference.) And there are a lot of people in the same boat. A lot of folks who spend a lot of hours in places with synthetic-fiber wall-to-wall carpet.
The upshot is that if microplastic from polyester fibers is a major health hazard, even if that only shows up late in life via a cancer effect, you’d think we’d have noticed it by now. We’ve had a lot of time and variation in chronic exposure to do so.
Restated: If there were significant human health effects from typical exposures to microplastic, you’d think we’d have noticed by now.
But how, from this viewpoint, can you explain why we are suddenly seeing and hearing so much about microplastic? How do you explain that, if it has, as you say, been there all along?
My guess? I guess that we’re now seeing it because we’re now looking for it.
One guess for the uptick is a change in or diffusion of microplastic-detection technology. The best studies seem to use some fairly exotic equipment, something I take to be a microscopic infrared spectrometer. Maybe those have gotten cheaper, or maybe it’s just the case that more people have access to the required equipment. Alternatively, other studies appear to use minimal equipment, but may require significant time. The publishable standard of measurement is so low (particles per liter) that maybe a lab with the right filter paper (and a microscope and some lab assistants) can quantify microplastic-in-blank to a publishable degree.
(I think that this last point, more than anything else, explains the view that microplastic is an inexhaustible source of clickbait, via finding microplastic in any (e.g.) bodily fluid or organ that you care to examine closely enough.)
A second guess for the uptick is that we now bother to look for microplastics, in both the human and natural environments.
One the one hand, maybe we look more often because “microplastic” is clickbait-du-jour. An internet-fed fad. A response to economic rewards for attracting eyes to your article. After all, every N days, somebody finds microplastic in some new (and yuck-inducing) substance and/or bodily fluid and/or internal organ. And that makes great clickbait. Particularly for the closet doomscrollers.
On the other hand, microplastic is part of a legitimate concern about plastic in the environment, overall. I mean, how many times have we heard this story, only to find out it has an unhappy ending:
There's this stuff? We use a lot of it. But it doesn't decompose well. So, where does it end up?
But in any case, I’m betting that any human health impacts of microplastic are pretty subtle. Not that I’ve done any research on that, but just from a feeling that we’ve been living with plastic for so long, I think we’d have seen something by now.
OTOH, I live in a house with polyester wall-to-wall. So take this FWIW.
