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I'm not a chemist. Why doesn't plastic get broken down? Will there be a future where my doctor will prescribe me an enzyme or something that will breakdown the plastics in my body so they can be filtered out, or turned into energy?

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Wood's cellulose was not broken down for millennia, and then live evolved ways to eat it (like mushrooms). But before then, there were piles and piles of dead trees.

I suspect plastics will be similar. Nothing has evolved to eat them, so nothing does.

It's happening[1], albeit slowly. Plastic is such an energy-dense substance that it seems inevitable something will eat it eventually. Might not be pretty though - imagine the kind of bacterial blooms that could happen in plastic-polluted waterways.

[1] https://www.theguardian.com/environment/2021/dec/14/bugs-acr...

Making plastic requires a specific step of heating to very high, specific temperatures and pressures and separating components of petrochemicals or similar biomass that cannot be easily reversed by aging or biological processes. A metaphor for this might be thinking about cracking an egg and scrambling it in a frying pan, then attempting to reverse this and put the egg back together only using mechanical steps and cooling - it's impossible by any practical means.

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