Microplastics seems to me like one of the toughest problems of our time.
Why?
Because even if we mostly stopped using plastics right now, which is laughably unrealistic, we would probably still be exposed to it for years or even decades.
Millions of tons of plastic particles at nano scale are floating on the oceans right now.
And inevitably, a bit of it will end up and is already ending up in people's bodies.
And just because they to a degree behave chemically inert, doesn't mean they do no harm, for example to our brains.
Now for many of the monomers/polymers, (first the fughi for the polymers, and then) the extremely high numbers of bacteria in the biosphere will find a way to metabolise them.
But my rudimentary knowledge of chemistry makes me think that there are probably some poly/monomers that just cannot be broken down by enzymes/biology, at least not at any relevant rate compared to the rate humanity emits them into the biosphere.
Maybe those monomers with fluoride? Not sure.
Now while bacteria will probably quickly, or have already, evolve to metabolise some of the plastics and thus use it instead of being hindered by it, humans and other animals will take ages for this.
It's one of the most profoundly careless and shortsighted things humanity is doing .. allowing the emission of molecules into the world that nature has no mechanism to process. Just because plastics is convenient.
Mirror life will also be a very tricky thing, but at least that is still at least a decade in the future.
But what do I even care ^^ .. maybe not until the majority of people on earth have Alzheimer's .. we may all live to nice old age .. what does anything at all matter if we can't make any sense of it or even just recognise our friends & family?