[ RadSafe ] Cancer risk low among residents outside the Fukushima Prefecture evacuation area
sperle at mirion.com
Sun Mar 16 13:13:07 CDT 2014
How about this Joe:
Cancer risk low among residents outside the Fukushima Prefecture
March 12th, 2014, Phys.org
Research group lead by Professor Akio Koizumi (Graduate School
of Medicine) and Prof. Hirohiko Ishikawa (Disaster Prevention Research
Institute) conducted a study, evaluating average radiation dose among
municipal residents near the evacuation area of the Fukushima Daiichi
Nuclear Power Plant. The survey performed exposure assessment based on
personal monitoring of external and internal radiation dose among
residents. Special endeavor was made to evaluate long-time dose over
time of the next few decades and predict quantitatively cancer risk.The
result of this research was published in the electronic version of
Proceedings of the National Academy of Sciences (February 24, 2014).
Comments from researchers
According to the radiological decay of radiocesium during next 10
years and 50 years, the average annual exposure is expected to be less
than 1 millisievert per year, which is the ordinary exposure limit
excluding medical and natural radiation exposure. In areas with high
radiation exposure (2.51 millisievert per year in 2012), average risk of
cancer incidence estimated from lifetime exposure dose of 2012 or
later, is 1.06% for all solid cancers (other than leukemia) and 0.28%
for breast cancer in women. However, continuous governing entrances to
contaminated forest, distribution of contaminated food, and assignment
of the hazardous zones is still needed to reduce radiation exposure of
the population and thereby reducing cancer risk.
The novelty of this study includes:
* Evaluation of the external exposure and internal exposure based on
personal monitoring and food duplicate method, respectively.
* Projection of the long-term exposure levels in next decades.
* Quantification of the cancer risk.
Average radiation dose of residents living outside the evacuation
zone of the Fukushima Daiichi Nuclear Power Plant (Kawauchi village of
Futaba county, Tamano area of Soma city, and Haramachi area of
Minamisoma city of Fukushima prefecture), ranged from 0.89 millisievert
per year and 2.51 millisievert per year in 2012 (taking into account of
the physical decay of radioactive cesium). The dose was close to annual
exposure dose due to natural radiation in Japan, 2 millisievert.
Radioactive substances were released into the environment by the
nuclear accident in March 2011, and local residents near the power plant
were evacuated. In this study, external exposure caused by radiation
from radioactive cesium in the soil and internal exposure received from
radioactive cesium in airborne dust and diet were investigated among
residents of three regions which are located at 20km to 50km from the
Fukushima Daiichi Nuclear Power Plant, and have borders on the
evacuation area. The survey was conducted between August-September,
2012. Study participants wore personal dosimeters to survey external
dose and provided food duplicate samples consisting of 24-hour meal and
beverage. Airborne dust samples were collected in each area. Among three
study areas, average external exposure ranged from 1.03 millisievert
per year to 2.75 millisievert per year, internal exposure from the diet
ranged from 0.0058 millisievert per year 0.019 millisievert per year,
and internal exposure from the airborne dust was less than 0.001
millisievert per year. As a result, external exposure accounted for
99.5% or more of individual exposure.
Kouji H. Harada, Tamon Niisoe, Mie
Imanaka, Tomoyuki Takahashi, Katsumi Amako, Yukiko Fujii, Masatoshi
Kanameishi, Kenji Ohse, Yasumichi Nakai, Tamami Nishikawa, Yuuichi
Saito, Hiroko Sakamoto, Keiko Ueyama, Kumiko Hisaki, Eiji Ohara, Tokiko
Inoue, Kanako Yamamoto, Yukiyo Matsuoka, Hitomi Ohata, Kazue Toshima,
Ayumi Okada, Hitomi Sato, Toyomi Kuwamori, Hiroko Tani, Reiko Suzuki,
Mai Kashikura, Michiko Nezu, Yoko Miyachi, Fusako Arai, Masanori
Kuwamori, Sumiko Harada, Akira Ohmori, Hirohiko Ishikawa, and Akio
Koizumi. "Radiation dose rates now and in the future for residents
neighboring restricted areas of the Fukushima Daiichi Nuclear Power
Plant." PNAS 2014 111 (10) E914-E923; published ahead of print February
24, 2014, doi:10.1073/pnas.1315684111
Provided by Kyoto University
On 3/16/14, 11:10 AM, "JPreisig at aol.com" <JPreisig at aol.com> wrote:
> Post something on Health Physics, Buddy.
> Joe P.
>In a message dated 3/16/2014 2:05:56 P.M. Eastern Daylight Time,
>sperle at mirion.com writes:
>There is enough speculation on all news shows so why are we continuing
>this dialogue on Radsafe? Does this have anything to do with Radsafe,
>remotely? Can we now move on.
>Sent from my iPhone
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