Comment by Mc_Big_G

Maybe, but my grandmother had Alzheimer's and lived in the country all her life and the air was extremely clean. However, her well water was disgustingly polluted with metals. I remember that she would wrap a giant wad of paper towels around her faucet and secure it with a rubber band as a poor man's filter. In a very short time the once white towels would be a dark rust color. I've been thinking for years that this might be the root cause of her condition. Surprisingly, her body was strong right up until her death. It actually seemed like a bit of a curse that her body forced her to continue living with a brain with a short-term memory of a minute or two. In any case, I seriously doubt the root cause for her was the air she was breathing.