I would 'hazard' a guess that the sun is the deadliest of all these. According to this article (http://www.cancer.org/Cancer/CancerCauses/SunandUVExposure/skin-cancer-facts) skin cancer causes 11,700 deaths a year in the US.

Wilson being an oncologist and very well prepared would now, of course, cover up in the sun, but the damage might already be done...