Annual effective dose of ionizing radiation from natural sources: United States based airline pilots compared with non-flying residents of the United States

An increased risk of fatal cancer from exposure to ionizing radiation is a health concern for airline pilots. This concern may be unjustified for most US pilots because: (a) for the majority of US pilots on 6825 flights, the annual effective dose of ionizing radiation from natural sources (on and off the job) is less than the annual effective dose to non-flying residents of Environmental Protection Agency Region 8 - a six state region in the US where the effective dose to non-flying residents from natural sources is 84% higher than that received by non-flying residents of the US as a whole - and (b) the death rate from cancer in the states in Region 8 ranges from 3% to 26% lower than the average death rate from cancer in the entire US. If epidemiological studies clearly indicate that airline pilots as a group are at an increased risk of developing fatal cancer, perhaps other factors in addition to ionizing radiation are involved. Another possibility is that the method of calculating the radiation dose received during air travel needs reevaluation.