Tamesy1 - re "Increased risk of melanoma in airline pilots"
I would suggest that this increased risk in pilots of Icelandic Airlines is far more likely to be mostly accounted for by increased sun exposure in far-off places than by cosmic rays. Add the fact that the majority of Icelanders have Fitzgerald Type I (pale, always burn, never tan) or II skins (rather than the darker and more protected Types III and IV) and the results are pretty unsurprising.
I don't have access to the paper itself, but if they did not take into skin type into account or seek data on cumulative sun exposure for each person surveyed then the paper doesn't really tell us anything much.
"The high risk of malignant melanoma appears to be exacerbated by jetlag. Regular flights over several time zones increased the risk even further." - these are characteristic of long flights, usually to sunny places. This is a more likely mechanism for melanogenesis than time-zone fatigue itself.
To do them justice, the authors do "...acknowledge that pilots have other occupational and lifestyle factors that affect the risk of skin cancer, such as exposure to sun, engine exhaust gases, ozone, and cosmic radiation."
Unfortunately a large number of papers published today reveal either insignificant trivia or matters of such crashing obviousness that one wonders what they hope to accomplish apart from yet another publication.
Incidentally, in a recent editorial, Daniel J Ncayiyana, the editor of the South African Medical Journal, pointed out that judged by it's own criteria, there is no evidence to support the proposition that so called "evidence based medicine" is any better than more traditional approaches....
Mac