What can I do about it? Romans could use pots made of other metals or materials, but whatever I use I'm going to get microplastics anyway. It would require a systemic change.
Even a systemic change wouldn't do that much, plastic doesn't break down into other things, it only separates into smaller pieces.
Even if we stopped using all plastic right now, the plastic that is already in the environment would still enter the food chain and accumulate in the top of it.
Take a look at this fan from the first half of the 20th century:
Note that it has a guard which protects the blades in case the fan falls over. However, the guard does not protect a person from accidentally sticking his fingers in the blades. Why not? It's not exactly complicated, it would have taken just a little more wire, and I'm sure people back then didn't enjoy having their fingers struck by metal blades any more than we would now.
In college I bought a fan like this on a garage sale because I liked the look and it actually worked. I called it Mr. Fingersnaps and every time I ran it it was very loud and smelled bad.
I mean BBB filter threshold is anywhere from 2.3 to 50 nm depending on pressure. Even though microplastics can get down to 1nm that is like an outlier. So in a situation where virtually almost all of microplastics must be filtered out, how does one get such a huge percentage as 0.1%?