sentences:  The EU legislators had found it convenient to incorporate the findings of the International Commission on Radiological Protection (ICRP) model for assessing radiation risk from internal emitters, but the ECRR challenged this and suggested that the model underestimates the risks
  by "at least" a factor of 10 "while..studies relating to certain types of exposure..suggest that the error is even greater".The ECRR have proposed a method of re-weighting the risk factors to take into account the biophysical properties of the particular isotopes involved.