It seems to me that the ICRP methodology does not even begin to deal with, and cannot be used to effectively project the results of bioaccumulation. But that is a major consideration going forward. The Japanese themselves are suggesting that children plant flowers to bioaccumulate radiation - the theory seems to be that they will then pick the flowers and take them to a charnel house where they will be turned into mulch and stored - (along with the bodies of all the people who planted and picked them. )
Thus while all of the world governments say that the increased (and expected) increases in measured radiation are not a cause for concern because the total dose is widespread, one wonders how much concern should there as these particle accumulate in the soil and are taken up by plants and animals and fish and reach the top of the food chain in significant doses. First they will tell you to drink less milk. Then none. If you can't drink cow's milk, you can't eat beef or cheese. Or anything else that grazes. Then certain vegetables will be discovered with too much radiation. If some of them have it, all of them do. We won't know. The government still refuses to admit the gulf oil spill still exists. The 'Don't Worry-Be Happy' solution. It can't hurt us if we don't see it!Read the first two paragraphs carefully. They are interesting enough that I have excerpted them here. Bolding and coloration are mine - Busby basically says that the ICRP model could be useful for direct radiation exposure but not for estimation the results of fallout. *****By Chris BusbyAssumptions and methodologyThe radiation risk model of the European Committee on Radiation Risk is described
in ECRR2010. It differs from the model currently employed by radiation protection
agencies which are based on the recommendations of the International Commission
on Radiological Protection ICRP. The latter ICRP model deals with radiation
exposure from all sources in the same way, as if it were external to the body, and
averages the dose to the body as if it were uniform across tissues more massive than 1
kilogram. The ICRP model then takes this dose and multiplies it by a risk factor for
cancer based on the cancer yield at high acute doses of the Japanese populations of
Hiroshima and Nagasaki who have been studied since 1952. This method cannot
apply to internal doses from radioactive substances, called radionuclides, which have
been inhaled or ingested in food or water. This is because these substances have
varying affinities for DNA and different parts of the body and can deliver very high
energy to local tissue. The ICRP method cannot be applied to inhaled or ingested hot
particles, which are solid but microscopic and can lodge in tissue delivering high
doses to local cells. There is a great deal of evidence that exposure to internal
radionuclides is up to 1000 times more harmful than the ICRP model concludes.
The ECRR risk model deals with this issue by adding hazard enhancement weighting
factor to the doses calculated for internal radionuclide or particle exposures. Collective DoseUp until recently the ICRP model employed a system known as collective dose. This
enabled calculation of the cancer yield following an exposure to a known population
of some given dose. The individual dose to a representative individual was calculated
and that was then multiplied by the population at risk. This gave the collective dose.
This number could then be multiplied by the cancer risk factor to obtain the cancer
yield. The ICRP abandoned this method, although it is quite a sensible approach. The
reason was that (a) it was felt to be politically embarrassing and (b) the ICRP risk
model was conceded to be strictly invalid for internal exposures since the uncertainty
was as high as 500-fold or more for certain internal radionuclide exposures. This
followed many studies of the effects of the Chernobyl Catastrophe which showed
much higher cancer yields than had been predicted by the ICRP model.
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