An official survey among 1,500 residents of three towns near the Fukushima nuclear plant revealed that hundreds of people were exposed to radiation above levels allowed for the general public, but below the limit required in order to enforce evacuation.
Some of the residents were evacuated soon after the March 11 accident, while others were not forced to leave until late April. At the time, the government was criticized by the public for its “slow reaction”.
The survey was carried out by the Fukushima Prefecture local government in the towns of Namie, Iitate and part of Kawamata and it measured the cumulative external radiation exposure on residents.
In other words, the survey measured the radiation exposure to the skin, and did not look at the so-called internal exposure, or radiation taken into human body from contaminated food, air or water.
The result shows that the accident's "impact on the health of the general public is extremely small," according to senior nuclear adviser Shunichi Yamashita, vice president of Fukushima Medical University.
Residents who worked at nuclear facilities were the ones with the highest levels of reported contamination. Five out of the 138 nuclear workers in the three towns were exposed to radiation levels of over 10 millisieverts, while the accepted level for the general public is one millisievert. The most elevated level was reported for a worker who received 37.4 millisieverts.
The residents were in general well below the 20 millisieverts limit set by the government for enforced evacuation in the event of nuclear emergencies.