A friend told me he attended a conference where one of the papers presented concluded that the person receiving the highest radiation exposure from the accident at Three Mile Island was a journalist who flew from Singapore to cover the story. A Health Physics Society report by Robert J. Barish has a good discussion about radiation exposure during air travel. It explains the exposure “…is caused not only by x rays (photons) but also by a variety of energetic particles such as neutrons, protons, electrons, muons ( a subatomic particle similar to an electron), and pions (another subatomic paricle described as the lightest meson). These “…come from a variety of cosmic sources in our galaxy, with a lesser contribution from our own sun”
The paper says,“…an airline passenger flying at an average altitude of 35,000 feet for a period of about 160 hours (75,000 miles) during solar minimum would receive an exposure at about the limit of the current acceptable level.” It further observed that there are just under half a million people who fly 75,000 miles or more a year as business travelers, and “…should be classified formally as occupationally exposed workers…”
I didn’t see any recommendations for the casual vacation flier who might want to follow the advice of some that no radiation exposure is acceptable. However, that doesn’t get to the point of whether the person receiving the highest radiation exposure because of the accident at Three Mile Island was a journalist who flew from Singapore to cover the story. The distance is about 10,000 miles, so the reporter would have been received about 13% of the annual “acceptable level” recommended by the Health Physics Society.
On the subject of radiation exposure from the accident, the World Nuclear Association published a paper that concludes there was not enough radiation released from the Three Mile Island accident to “…cause any dose above background levels to local residents. There were no injuries or adverse health effects….”
The Pennsylvania Department of Health maintained a registry of 30,000 people who lived within five miles of the accident. It was discontinued in mid-1997 without any evidence of unusual health trends. Independent studies found no evidence of abnormal numbers of cancers. Calculated radiation exposure was about 1/3 of the average level of radiation received by U.S. residents in a year. A U.S. District Court Judge dismissed a class accident lawsuit alleging the accident caused health effects.
The most troubling effect on the public was from frightening statements made by people who oppose nuclear energy and used the publicity of the accident to further their cause. The paper concluded, “The only detectable effect was psychological stress during and shortly after the accident.” The many exaggerated and false media reports resulted in people leaving the area in the family car despite the risk of car crashes.