How long have you been trying to work out to take harmful gases out of the atmosphere

Question: How long have you been trying to work out to take harmful gases out of the atmosphere
- Keywords:
  atmosphere,
  gas,
  harmful,
  work
Asked by anon-239827 to Struan, Isabel, Douglas on 20 Mar 2020.
- Douglas Bray answered on 20 Mar 2020:
  
  This is actually not my area of study! But i do work with plants that remove carbon dioxide from the atmosphere.

Question: How long have you been trying to work out to take harmful gases out of the atmosphere