I actually work in the wastewater industry and from what I'm reading, a properly functioning sewage treatment plant already captures a very high proportion of microplastics. This widely cited study noted above 98% removal efficiency at one plant.

We're already at approaching 2 log (99%) removal without actually trying to. It doesn't seem improbable to me that with a few relatively modest tweaks to the system we could get 3 log removal (99.9%). Getting to 4 or 5 log removal is likely where things will get really expensive and challenging. But for now, a 2-3 log removal is probably good enough to focus on other sources like tire fragments/dust that typically pass directly to receiving waters with no treatment at all.

[–] AA5B@lemmy.world 1 points 8 months ago

Good to know, thanks. While I don’t know how my system does with this , the treatment facility is new-ish and was supposed to be state of the art.

But then we’re back to needing to know more about the sources of environmental microplastics, then figure out how to cut them