[curryst]

I don't think you really understand the implications of that statement. You can't even have bronze-age level technology with 0 carcinogens. At least not with present technology.

You can't burn wood. You can't heat a lot of metals. Practically anything that requires smelting metal is out because of the preceeding two. Eletrical power is basically a non-starter, because the mining and refining both release carcinogens.

We need more advanced technology to be able to truly isolate those emissions, but we don't have the ability to develop that technology without releasing those emissions. The goal should be managing the amount of emissions we allow, and prioritizing the "emission credits" towards goals that can reduce those emissions further.