Yeah. Major sources of everyday microplastics are: 1. Washing synthetic clothes in the washing machine 2. Normal wear and tear of tires

This made me go from being very alarmed to the realization that if these things causes major harm, we would have undoubtedly known about it by now

Generally foreign contaminants introduce chronic immune responses. A rise in autoimmune disorders could potentially be a result. Or perhaps a single particle has a small chance of inducing cancer in a cell that endocytically engulfs it. In a situation like these the effects of low numbers will be small and hard to attribute to the source but that doesn’t mean it won’t continue to make it much worse for us.

Significant amounts of plastics are also found in plants.[0]

[0] https://news.ycombinator.com/item?id=23611874

That’s why I mentioned I’m sure they are everywhere, so maybe I’m overcautious.

At the same time though I’m certain any marine life is subjected to way more micro plastics than those on land. So consuming anything that functions as a filter is gonna have high concentrations of it. At least that is my logic.