With a recent Horizon episode (13th July) on the pointed failure of radiation released at Chernobyl to produce a 10s of thousands of deaths predicted & indeed the possible benefit of low & intermediate level radiation (an effect known as hormesis) perhaps your readers would be interested in an even more clear cut case.
In 1983 a group of 180 apartment buildings was completed in Taiwan. Somebody had made a serious mistake. They had mixed into the concrete a considerable amount of highly radioactive cobalt 60. This meant that ultimately 10,000 people lived in buildings for from 9 to 20 years so radioactive that they received an average of 74 mSv of radiation per year in 1983, declining thereafter as cobalt 60 has a half life of 5 ½ years. This compares with a rate of 0.5 mSv above background which is the normal maximum exposure for radiation workers & total of 15 mSv maximum safe limit for land fit for habitation according to US government standards. According to the linear no threshold (LNT) theory currently in use world-wide for assessing nuclear risks there is no lower limit to the level at which radioactivity kills (hence the term "no threshold") & this, inhabited for a decade & a half before the radioactivity was traced & measured, should be the site of a truly massive cancer death rate. It isn't.
A thorough & methodical tracing of all the 4,000 families by a team led by W. L Chen of Taiwan's Director of Medical Radiation Technology of Taiwan's National Yang-Ming University (the full report is available in English on http://www.jpands.org/vol9no1/chen.pdf ) has resulted in an unequivocal & spectacular result. Cancer rates in that highly radioactive building are down to 3.6% of prevailing Taiwanese rates.
For many years there has been an unfashionable alternative to the LNT theory called hormesis. This is an effect, long observed in plants & cultures, whereby intermediate level radioactivity actually stimulates life & improves health. < There has been significant evidence for this (the deaths at Hiroshima did not appear to fit the LNT pattern, there are places in India & Iran with background radiation of 15mSv or higher with no observed increase in cancer & numerous studies of radon in homes have found a reverse correlation between radon levels & cancer - deleted >. Nonetheless, such has been our fear of all things nuclear that the LNT theory has been absolutely accepted despite the fact that there has NEVER been any actual evidence for it. This study, however, is so detailed, has such well-defined boundary conditions & in proving a reduction in cancers of 96.4% has such a clear result that there can no longer be any intellectual doubt whatsoever. Radioactivity, up to 50mSv, is good for us.
Yours Sincerely
Neil Craig
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