Wednesday, April 27, 2011

European Committee on Radiation Risk estimates Chernobyl's cancers will total 1,400,000 in 50 years

European Committee on Radiation Risk estimates Chernobyl's cancers will total 1,400,000 in 50 years


On the 25th anniversary of the Chernobyl catastrophe ECRR (European Committee on Radiation Risk) published calculations of cancer resulting from the fallout.

As with its forecasts for cancer in Japan after Fukushima, the Committee has used two separate methods: the "Tondel" method and the "ECRR Absolute" method.

The "Tondel" Method is based on a conservative study by Martin Tondel which examined cancer incidence in northern Sweden during 10 years after Chernobyl. Tondel differentiated the varying levels of land contamination and found that the disease increased by 11% for each 100 kiloBecquerels of fallout per square metre of land surface.

The "ECRR Absolute" method employs weighting factors developed by the ECRR to correct for the inadequacy of "absorbed dose" quantities on which the ICRP risk estimates are based. The ECRR weightings take account of the different ways in which different radionuclides behave in biological systems. See ECRR Recommendations (a free download) for detail.

ECRR has applied these methods to UNSCEAR and UNESCO data for fallout in 39 countries with a combined population of 2,342 million people.

The "Tondel" Method forecasts approximately 492,000 incident cancers in the 10 years following exposure over and above the numbers expected in the absence of radioactive fallout. The "ECRR Absolute" method forecasts 1.4 million additional cancer cases in the 50 years to 2036.

There is good agreement between these results obtained by the two methods. The yield of about 1.4 million cancers worldwide also agrees quite well with the calculations of John Gofman, Rosalie Bertell, and Alexey Yablokov.

It should be noted that the ECRR method was developed in 2003, before Tondel et al published the results of their study of cancer in Sweden. The ECRR 2003 method predicted what they found with a fair degree of accuracy.

It should also be noted that the Caesium contamination levels associated with the Tondel findings give annual external doses of about 3mSv (according to ICRP methodology). This is roughly the same as natural background and should not have caused any observable increase in cancer, according to the ICRP model.

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