Answer to Question #9935 Submitted to "Ask the Experts"

Category: Nuclear Power, Devices, and Accidents — Nuclear and Radiation Accidents

The following question was answered by an expert in the appropriate field:

I am traveling to Osaka, Japan, in the fall of 2011 for business and will be in Osaka for five days. Should I be concerned about the nuclear radiation? And is there any protective measure I can take to protect my health?
Given what I have read and heard about the situation in Japan, I do not believe you have to be overly concerned about any excessive radiation exposure when you visit Osaka. Osaka lies about 375 miles southwest of the Fukushima-Daiichi nuclear site that was so badly affected by the catastrophic tsunami event last March. From what I have been able to learn, the external radiation levels and the radioactivity levels in food products in Osaka have not risen beyond normal background levels that existed prior to the event.

Additionally, the situation has continued to improve with respect to releases of radioactivity and effects on areas closer to the site. As of around the end of September 2011, the Japanese government lifted advisories that extended to individuals within about 12 to 19 miles from the reactor site; this means that such individuals who had been requested to evacuate the area or, in some instances remain inside to the degree possible, may now return to their homes and resume more-or-less normal lives.

Monitoring of both external radiation levels and radioactive contamination of food and other media continues. Also, as of the end of September, the three affected reactors had cooled to or below 100o C (near the bottom of the reactor core vessels) and are proceeding towards a declared condition of “cold shutdown,” a condition that will be declared when the temperatures reach 90o C.

If you should decide to do any touring much outside of Osaka, and you expect to be within 30 miles or so of the Fukushima reactor site, you might expect to find some locations where radiation levels and radioactive contamination are measurably above background, but not at levels that I would be especially concerned about significant exposure from routine activities. In such situations I would, however, recommend that you avoid eating locally grown foods that might be available from local farmers and that may not have passed through the government inspection process. This is a simple precaution to take account of possible food contamination so as to avoid unnecessary intakes of some radioactive products that were dispersed from the reactor site. 

I hope you feel comfortable about the current situation and that you fully enjoy your trip.

George Chabot, PhD
Answer posted on 2 November 2011. The information posted on this web page is intended as general reference information only. Specific facts and circumstances may affect the applicability of concepts, materials, and information described herein. The information provided is not a substitute for professional advice and should not be relied upon in the absence of such professional advice. To the best of our knowledge, answers are correct at the time they are posted. Be advised that over time, requirements could change, new data could be made available, and Internet links could change, affecting the correctness of the answers. Answers are the professional opinions of the expert responding to each question; they do not necessarily represent the position of the Health Physics Society.