So2: Sulphur dioxyde is a poison.
Officially tolerated: 75ppb
To fully understand the problem, So2 is a heavy gas that enters the soil around it is created thus polluting densely populated areas where it is emitted in big quantities, cities and industries.
In China, where the levels are many times if not most of the times in many places like Beijing, Hong Kong, Chongqin, Wuhan, it is tens of million people exposed since birth ...
So2 is all the more dangerous that it is easily diluted in water, and most of it finishes in water like most of the numerous pollutants nowadays and for tens of years ...
Co, carbon monoxyde is a deadly gaz from fossile fuel combustion ans was used in Nazis' gas chambers, for suicide purpose in the 19th century for instance. Co is impairing cognitive abilities in low doses and is a poison for the heart and lungs.
Co2 is much less relevant on the contrary to what is said but not concerning water where it ends like So2 for its most part, leading to the acidification and the warming of the water mass in the world, which means less plancton, the first oxygen provider, less oxygen so.
(Btw, who's the real destroyer around ? China by a long shot, China the belly of the Western material world for which millions are dying and milliards suffering. And what for ? To be its slave. Official in London, undocumented in Lybia with all the inter levels ...)
For India, read that
CHONGQIN, So2 : Deadly permanent levels
1000 micron gram/m3 as a norm ?
Beijing - Tianjin : permanent deadly levels of Co (~30M inhabitants)
3000/4000 ppbv in Beijing metro area are common !!