It should not be, "Cockpit crew had a low all-cause, all-cancer, and cardiovascular disease mortality but elevated aircraft accident mortality." [1]

In plainer, much less careful English: even with that exposure, they live longer than average.

[1] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4511278/

You could consider this an artificially selected population, since to keep an airline transport pilot license it is required to maintain a current FAA medical. I'm sure lots of pilots smoke, drink and eat poorly, but they try to avoid getting grounded and career-ended by their physician.

There was a good study and results that just came out about this in the past couple of weeks and it backs up that airline crew have higher cancer rates:

https://www.nytimes.com/2018/07/05/well/airline-crew-have-hi...

There may be a concern, but so far, there's been no evidence to support there is any safety risk.

There is a noticeably higher risk of cataracts, at least. https://www.ncbi.nlm.nih.gov/m/pubmed/16087845/

Interesting. Didn't know that.