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Radiation risk in Japan: an update

March 19, 2011


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IT Consultancy Services
September 23, 2011

It is good to read about the radiation risk . It is a very informative post. You have provided a wide range information it will help a lot.

Debora Browy
June 30, 2011

Hello, I am an American in Japan and was here during the March 11 earthquake/tsunami (in fact it was my birthday) anyway, I am concerned about the air quality here with the cooling ponds and reactors continuing to be cooled manually and quite a lot of steam being released into the atmosphere here and then we have daily rain during June…does this carry the radiation further across Japan? I am in the kanagawa prefecture where some hot spots were found and should I still be using bottled water?

David Konn
August 16, 2011

You should definitely be concerned about radiation. Become more educated about the actual status of the continuing radiation problem (now its August 5 months later!) I have found the most reliable information comes from a nuclear engineer with over 20 years experience.

There are some things that you can do to help protect you.

April 23, 2011

Hello, thanks for the useful information. I was wondering about how long might any contamination of car parts last, assuming it is inside or under the vehicle, where it cannot easily be washed (by, say, rain water…)?


March 29, 2011

How serious would exposure to safe or low levels be over a period of time? I guess what I am asking is it cummulative? either by exposure or ingestion?


B. Bierck
March 29, 2011

In my view, there’s a need in much of the reporting and analysis to keep in mind that emission of radiation is not the same thing as emission of radioisotopes. Radioisotopes are the radioactive elements which emit radiation, and it’s important to follow where they can go after they are emitted.

Transport of particles containing these radioisotopes is one of the big issues here because people can be exposed to radioisotopes through various routes, such as ingestion of water or food containing them, or inhalation of particles they can be “riding” upon in the air. Ingestion of very minute quantities of some radioisotopes can be a serious matter if these elements are incorporated into body tissue or bone mass. From within the body, emissions of very low doses of radiation can be have significant health consequences.

lew liggett
March 23, 2011

Could you please comment on the opinions of Dr John Gofman, Cal Berkeley and Lawrence Livermore Lab regarding radiation exposure. He worked on the development of the atomic bomb, was one of the world’s foremost radiation experts, and wrote in his book ” Radiation and Human Health ” that any exposure to radiation, even backround, would increase the risk of cancer. Dr. Gofman was a leader of the anti-nuclear power movement. Thanks.

Saori Harada
March 21, 2011

Hi Peter,
Radiation spread through air worries us,
and at the same time, the risk of radiation intake through tap water and food is becoming another issue.
The Japanese government announced that at most 5200 becquerel (about 17 times as high as the government’s safety limits for food) of radioiodine
was detected from a liter of milk near the Fukushia Daiichi nuclear power plant.
Also, they announced that the excess level of radioiodine and radioactive cesium were detected from spinach near there (note;it was measured without washing the spinach).

Japanese experts say even if we drink the milk, human body take in about 120 microsieverts of radiation, and that number is far less than the dangerous level,
and about the spinach, the radiation intake can be about one-twentieth of a CT scan when we cook it.
However, the agricultural cooperative association began to collect those food, and it is heartbreaking that milk cows and vegetables are disposed of…

What is the exact level of radiation we should be careful of, regarding food and tap water?
Are there any kinds of safety limits similar to this in States?

I’m in Tokyo now, but I was in Boston when the earthquake and nuclear crisis occurred in Japan.
Through watching the news in both countries, I realize there is a differnce between them…especially about the radiation problem.
For example, America set the evacuation area within 80 kilometers from the nuclear power plant, on the other hand, Japan set it within 30 kilometers.
All the people from other countries are now gone even from Tokyo, which really scares us.

So, I’m looking forward to hearing your opinion. Thank you!

Peter Wehrwein
March 21, 2011

Sorry, this won’t answer your questions about what’s going on Japan. But today [Monday, March 21, at 6 p.m. EDT], the FDA updated what it is saying about food safety situation here in the United States as it relates to Fukushima. Click here to link to the agency’s question-and-answer page.

Shigeru Suzuki
March 19, 2011

Hi Peter,
Thanks for more details about the clear explanations for the numerical values of radiation with regard to Fukushima Nuclear Plants.
Although we have some sources of information about the radiation safety in general, there seems no reliable reference written in Japanese.
I appreciate your further post about the radiation safety if possible, so that I could understand the true danger and safety of Fukushima’s case.

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