A typically great piece by Steve Packard examines the “many times debunked linear non-threshold model” in the medical imaging context. And I liked Steve’s “falling off a building” metaphor:
(…) By this logic, one rem should result in .1% the likelihood of developing cancer as 1000 rems. This has been likened to observing that when a person is thrown off a ten story building they die 100% of the time, when thrown off of a 5 story building, they die 50% of the time and therefore assuming that 10% will die from a one story fall and 1% will die after falling 12 inches. Furthermore, the implication is that the optimal living situation is zero radiation exposure (something which is effectively impossible) and the higher the exposure is over zero, the worse off you are for cancer risk.
Needless to say, many have pointed out that there’s a flaw in this logic and as knowledge of radiation has increased, LNT has begun to look less and less likely. Unfortunately for the promoters of LNT, examination of the cancer rates in populations living in high radiation background areas shows no increase in cancer and in fact, has produced some evidence of a decreased risk of cancer.
This is a longish, thorough and well resourced essay. Do read the whole thing. Also, one of the papers Steve linked I’ve not seen before — it is excellent: The Rise and Fall of the Linear No-Threshold (LNT) Theory of Radiation Carcinogenesis.
For more studies and resources on LNT see this earlier post.
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