WHO estimates radiation impact on Japanese people

May 24, 2015

Namie, Iitate exposed to radiation doses within 10 to 50 millisieverts

http://mainichi.jp/english/english/newsselect/news/20120524p2g00m0dm033000c.html

TOKYO (Kyodo) -- Radiation doses to individuals from the Fukushima Daiichi nuclear crisis were the largest within a dose band of 10 to 50 millisieverts in the town of Namie and the village of Iitate in Fukushima Prefecture, the World Health Organization said Wednesday in a preliminary estimate.

"In these most affected locations, external exposure is the major contributor to the effective dose," the WHO said.

Doses were estimated to be within a band of 1 to 10 millisieverts in the rest of the prefecture and 0.1 to 10 millisieverts in most of Japan, the WHO said.

All doses are below 0.01 millisieverts outside Japan.

The WHO made the estimates by considering major routes of exposure -- external exposure and internal exposure from ingestion of foodstuffs and inhalation, based on data made available by the Japanese government through mid-September in 2011.

Given limited information available, the assessment contained a number of assumptions, such as radioactive cloud composition and dispersion, time spent indoors and outdoors, and that people in the most affected areas outside the 20-kilomter radius from the Fukushima plant continued to live there for four months after the accident caused by the March 11, 2011, earthquake and tsunami disaster, the WHO said.

"All efforts were made to avoid any underestimation of doses," it said.