According to the new study, the inhabitants of a village sixty kilometers away that were not evacuated do not have to worry about dangerous levels of radiation over their lifetime.
The scientists also discovered that natural radioactive decay and weathering from rain should get more credit for reducing radiation, than do expensive decontamination efforts, such as topsoil removal.
The released results should help the citizens make a decision whether to return to areas where evacuation orders are being lifted.
Of the 11 municipalities in the region that were originally designated evacuation area, five have had their evacuation orders wholly or partially lifted since April 2014.
Four other orders will be lifted on March 31 and April 1, rolling back the evacuation zone by approximately seventy percent.
Nearly twenty thousand registered residents in the five municipalities are now free to return home, but only 13.5 percent have decided to do so.
According to surveys, concerns about exposure to radiation and slow infrastructure restorations are the main reasons why a majority of evacuees have not returned.
In Naraha, where the evacuation order was completely lifted in September 2015, only 781 of 7,276 have returned home, most of them the elderly.
"I want to return home because it is my hometown, but I worry whether commercial facilities and medical institutions can continue operations in a town without young people," said a housewife in her sixties.
The central and local governments have worked tirelessly to lure back former and new residents, through facility and infrastructure construction.