Excerpts from the letter:
The nuclear reactor accident at Fukushima Daiichi that followed the earthquake and tsunami in 2011 prompted well-intended measures that have had disastrous consequences. These were not caused by the radiation itself but by the social stress, the forced evacuation, and the ongoing displacement of tens of thousands of people. Both the stress and the population relocations are based on the fear of low-dose radiation that originated from the use of the linear no-threshold (LNT) model for radiation-induced cancers and its associated “no safe dose” mantra.
The mistakes made at Chernobyl concerning prolonged evacuation were repeated in Fukushima in spite of the acknowledged adverse health consequences from the prolonged evacuations with little projected benefit, since the radiation doses avoided were too low to have resulted in any detectable harm.
If the evacuated Fukushima area residents had returned to their homes and resumed normal activities in 2012, the maximum additional radiation dose they would have faced has been estimated to be ~8 mSv/y by Harada et al. 2014 for the regions considered, while doses up to 12 mSv/y have been estimated in the UNSCEAR Report, 2013 (Table C19). These modest dose-rates would decrease every year. Considering the wide variation in annual natural background radiation doses around the world, and the lack of observed increases in cancer rates in areas having higher annual doses than noted above, repopulation would not have posed an increase in cancer risk, notwithstanding the current use of the LNT model.
Signed, members of Scientists for Accurate Radiation Information