if the pollution in our air doesn’t decrease, how long will it take for the earth to be inhabitable?

Question: if the pollution in our air doesn't decrease, how long will it take for the earth to be inhabitable?
- Keywords:
  air,
  earth,
  inhabitable,
  pollution
Asked by anon-177563 to Daniel on 11 Jun 2018. This question was also asked by anon-177576.
- Daniel Marsh answered on 11 Jun 2018:
  
  The air pollution has many mechanisms that affect your health, both respiratory as well as cardiovascular. If we didn’t reduce current pollution levels but it didn’t get any worse either we wouldn’t necessarily make the earth uninhabitable but we would all live less healthy, shorter lives with greater risk of disease than if you lived somewhere cleaner.

Question: if the pollution in our air doesn't decrease, how long will it take for the earth to be inhabitable?