Radiation Fears Strike Again: The Culprit? Bad Math.

August 11, 2011

An online news site based in Vancouver recently posted an article called Japan’s Fukushima catastrophe brings big radiation spikes to B.C.

The article claims that levels of airborne Iodine-131 in Canada shortly following the Fukushima accident, far exceeded the regulatory limits. It says, for example,

For 22 days, a Health Canada monitoring station in Sidney detected iodine-131 levels in the air that were 61 percent above the government’s allowable limit. In Resolute Bay, Nunavut, the levels were 3.5 times the limit.

This is, however, based on flawed calculations and a lack of understanding of the publicly available information presented on the CNSC website.

The CNA responded with this letter to the editor:

I read Alex Roslin’s article “Japan’s Fukushima Catastrophe Brings Big Radiation Spikes to B.C.” and wanted to clear up some misinformation that is presented in the article. There are many instances where it is stated that levels of airborne Iodine-131 exceeds federal limits; however this is not true according to publicly available information from the CNSC and Health Canada.

Airborne Iodine-131 from Fukushima was identified in the article as exceeding 200 milli-Becquerel per cubic meter (200mBq/m3). This value was presented on the CNSC website for the purpose of showing what certain concentrations in air meant in terms of dose if exposed for an entire year. In fact, the CNSC website states “These values should not be construed as regulatory limits set by the CNSC, but rather as reference values provided for context.” The highest recorded level in Canada occurred on March 29, at Resolute Bay in Nunavut and was measured to be 9.76mBq/m3. In this case, the concentration was only present for a single day.

Estimates for the dose to Canadians as a result of Iodine-131 from Fukushima are 500,000 times less than what has been shown to have any negative health effects. Equivalent activities that would give you the same dose include getting 1/50th of a panoramic dental X-Ray, or 6 hours worth of cosmic background radiation.

Radiation is part of our natural environment and has been present in our lives for much longer than human history, at levels that are hundreds, if not thousands of times more than what was received as a result of Fukushima. Canadian knowledge about radiation has saved and improved the quality of life of millions of people, at home and around the world in the fields of medicine and science. The article written by Alex Roslin is poorly researched and I urge all Canadians to think critically and use their own good judgment before believing false arguments.

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James Harrington
Project Researcher
Canadian Nuclear Association.

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