FGR is interesting and gives some insight into how this bureaucratic world functions A couple of things I noted The table of p shows a good dozen elements including Ca where the values changes by well over and order of magnitude from on model to the next The following summary on p  says for about  of radionuclides the differences are not substantial ie less than a factor of four   That points out that none of these figures are derived from actual physical measurements but from computer models Also there is no qualification on the uncertainty of these values as one would expect if it was a scientific test which it is not  its a model  The magnitude of the changes and that fact that a factor of  is seen as not substantial gives an idea of how reliable the number may or may not be   httphealthphysiiteduextendedarchivemsghtml I dont know what the exchange rate for K is but it is prsesent in signif icant amounts in the urine at concentrations that vary comparatively widely This would suggest I suppose that the body regulates K very closely disposingof excess amounts very rapidly  Perhaps someone should do a study by feeding Reference Bananas to  his dots   httphealthphysiiteduextendedarchivemsghtml  I have found this Banana Equivalent Dose very useful in attempting to explain  infinitesmal doses and corresponding infinitesmal risks to members of the public  Interestingly the antinukes just HATE this and severely critisize us for using such a deceptive concept  Would love to go into more detail but have to get back to our DEADLY Human Radiation Experiments ie eating bananas  Considering the fact that the DOE has officially stated that there is no safe dose of radiation my advice to you all is to stop eating immediately  Disclaimer  Neither Lawrence Livermore National Laboratory the University of California nor the Department of Energy recommends eating bananas    So it seems the advocates of this BED idea do regard it as a bit of an insider joke and take joy in using it to be provocative   But if the K in a banana is  times more potent than that already in muscle tissue there is still a substantial problem somewhere   At least this is getting closer to understanding where it comes from and how it is calculated