In my opinion it is our primary responsibility for everyone to keep the air clean. In this present world every one is indirectly contributing for the growth of air pollution.
For example, we use cars everyday that release carbon monoxide, which can result increase in air pollution and global warming. That is why I don't use car regularly. Instead, I prefer public transport like metro trains, buses, etc. I also plant a tree every year.
Trees can reduce the levels of carbon dioxide in the air. My contribution in reducing air pollution may be less, but if each and every one in this world feels responsible and contributes to such activities, we can greatly reduce the extent of air pollution.