DR.TSUBOKURA'S RADIATION LECTURE VOL.164

Author: Masaharu Tsubokura M.D., PhD.

Editor: Yudai Kaneda


327  Radiation Exposure from Food

May 15, 2021


International organizations have been releasing evaluation reports on radiation exposure and its health effects due to the recent nuclear accident. One of the most representative reports is the one United Nations Commission (UNSCEAR) issued.


The report’s latest version, the “2020 Report,” was released in March 2022, and the results this time regarding the amount of internal exposure food caused were significantly revised downward (smaller values) compared to the previous 2013 report.


For example, the "maximum value" of exposure of the thyroid gland of a one-year-old child who is highly sensitive to radiation, was approximately 30 millisieverts for those who evacuated after the nuclear accident, which is less than half the value reported in 2003. The maximum value for those who had not been evacuated in the prefecture was even lower, at approximately 20 millisieverts. It has also become clear that the route of exposure to the thyroid gland was not through food, but rather through breathing.


Therefore, according to the 2013 report, the possibility of an increase in cancers could not be dismissed if there were many children exposed to the maximum amount of radiation. However, the current report has indicated that the exposure level is even lower, thus the report has been revised to assume that the possibility of increased cancer is slight.


328  Reasons Why Radiation Effects Are Unlikely

May 22, 2021


International organizations have been releasing evaluation reports on radiation exposure and its health effects due to the recent nuclear accident. One of the most representative reports is the one the United Nations Commission (UNSCEAR) issue. The latest version of the report was released in March of this year and is referred to as the “2020 Report.”


The current reports states that many thyroid cancers found thus far after the accident are probably unrelated to radiation exposure. There are several reasons for this.


First, the thyroid exposure levels are slight. As mentioned last week, the estimated dose to the thyroid gland has been revised to a smaller amount than before. This means that thyroid cancer will unlikely increase with radiation.


Second, many of the thyroid cancers that have been found after the accident were found too early. It takes years for cancer to develop due to massive radiation exposure. The increase in thyroid cancer after the Chernobyl accident was not seen in the first four years. In contrast, about half of the thyroid cancers found after the recent accident were discovered within four years of the accident.


 

The Japanese version of the manuscript was originally published in Fukushima Minyu, a local newspaper in Fukushima prefecture, Japan, on 15 and 22 May 2021 was reproduced for MRIC Global under the author's permission.

RECENT POSTS
ARCHIVES
CATEGORIES
TAGS
RSS
RSS Feed