I lived in LA for 20 years (moved about 2 years ago -- hope I didn't sell you my condo!) -- and was right by LAX with a view of departing planes over the ocean, right from my balcony. Never had any health issues, still have all of my hair.

My mother was just diagnosed with dementia, and her mother had it before she died. Despite my "anecdata", I am keeping a close eye on these sort of findings, to see if my brain is going to go the same way. I've certainly had a higher pollution load in my life to date than either of them. :/