I think it's most likely that the change in risk is attributable to the risk of nonsmokers going down because of the reduction of environmental carcinogens. The banning of asbestos alone probably accounts for a huge chunk, plus lower emissions vehicles, cleaner factory and energy production, etc.
I think it's most likely that the change in risk is attributable to the risk of nonsmokers going down because of the reduction of environmental carcinogens. The banning of asbestos alone probably accounts for a huge chunk, plus lower emissions vehicles, cleaner factory and energy production, etc.
That was my favorite hypothesis by a long way, but it doesn't look like risk for non-smokers has actually gone down. I'm baffled.