When it comes to drinking water the microplastics is already a solved issue, the problem is that its relatively expensive because it has to be done in each home. The solution is a carbon block filter. They go for about $50 afaik excluding the contraption it sits in, and lasts at least 6 months. You basically use them until the water flow is noticeably reduced, then you buy a new one. But some people rinse the old one somehow and give it a bit more milage.

The linked paper is about exactly that: PFAS levels in rainwater have exceeded levels deemed safe for consumption