73 years ago today, many precious lives were instantly destroyed by the terrible blast and the heat from the atomic bomb. Did you know, however, that the atomic bomb has had another, lasting effects? It’s an invisible, quiet and lasting effects from the nuclear bombing, called “internal radiation exposure.”
Katsurao Village: its whereabouts and evacuation/return policy history
In June 2016, the evacuation order applied to Katsurao village after the Fukushima Daiichi Nuclear accident was lifted for 80% of its territory. The northeast part of the village in the vicinity of Namie town is still classed as a ”difficult-to-return” zone, where the annual airborne radiation dose is over 20mSv. The lifting of the evacuation order of this area is not planned.
In June 2018, approximately 300 people are living in the village, which is about 20% of the population before the accident. In April 2018, primary and junior high schools opened where 18 children are currently studying, whereas in 2010, before the accident, 112 children were attending schools.
We have published several soil contamination maps of the “Fukuichi area environmental radiation monitoring project” in this blog (see maps of Namie, Minamisoma 1 & 2 ). Normally, the government should carry out the measurements, but the government relies on the air radiation dose measurements at the expense of the radio-contamination measurements found on the surface and in the air (in terms of the volume of radioactive substances). To fulfill the lack of this essential information for the radioprotection of the population, civil groups conduct soil measurements.
We have published several articles in this blog saying that to protect the population the Japanese goverment should take into account the soil contamination as well as the radiation dose in the air. The policy to open the evacuation zones and encourage the population to return to live there (with the end of financial compensation and relocation aid) is based only on the airborn radiation dose measurements (the evacuation order is lifted when the radiation dose is under 20mSv/year). We have been saying that this is very dangerous, even criminal, for the air radiation dose rate (indicating the amount of radioactive dose received by a person within a certin period time) is useful with a well-identfied fixed source of radiation, but is not adequate to reveal the overall environmental contamination after a nuclear accident. It doesn’t account for the internal radiation exposure induced health hazards (note 1).
On September 5, 2017, Minami-soma city made a statement on the city’s radiation levels compared to 3 cities in West Japan, which has been reported in several newspapers. It’s important to comment on this study because the statement is intended to persuade the population to return to live there.
Fukushima city is going to host Olympic baseball and softball games in 2020.
What is the level of radio-contamination there? This is the question on everybody’s mind, spectators and players from all over the world. Is it really safe?
The evacuation orders of the most populated areas of Namie, Fukushima were lifted on March 31, 2017. We are publishing the most recent soil surface density map of Namie created by a citizen’s measurement group named the “Fukuichi Area Environmental Radiation Monitoring Project“. Their members are mainly from Tokyo metropolitan region.
We are presenting here a transcription of an NHK TV documentary (note1) on insoluble radioactive particles found in Fukushima and in the Tokyo metropolitan region. This is the 3rd part of the 3 parts. Here is the 1st part. Here is the 2nd part.
As you can see below, small insoluble radioactive particles are dispersed in the Tokyo metropolitan area. We believe that this represents serious health problems for the population in terms of internal irradiation, since the insoluble radioactive particles remain in the body for a long time. For anybody who would stay in this metropolitan area, further radioprotection against internal irradiation would be required.
We are presenting here a transcription of an NHK TV documentary (note1) on insoluble radioactive particles found in Fukushima and in the Tokyo metropolitan region. This is the 2nd part of the 3 parts. Here is the 1st part.
Insoluble radioactive particles that do not dissolve in water.
This characteristic is supposed to make a big difference when considering health effects.
In the past, radioactive cesium emitted in the nuclear accident was thought to be carried away adhering to water-soluble particles called aerosols in the atmosphere. When it touches the water the particle melts and the cesium diffuses and gets diluted. The same is true when it is inhaled in the lungs; the water-soluble cesium melts into the body fluid and spreads thinly throughout the body. Then it is supposed to be discharged gradually by the metabolic activity, and decreases by half from 80 to 100 days in the case of adults.
We are presenting here a transcription of an NHK TV documentary (note1) on insoluble radioactive particles found in Fukushima and in the Tokyo metropolitan region. Since it is quite heavy with images, it will be uploaded in 3 parts.
These particles contain cesium, which has the property to dissolve in water. However, in the case of these particles, the cesium was taken into glass-like particles during the Fukushima Daiichi NPP accident before it was blown away by the explosion. These particles do not dissolve in water, and as a consequence the cesium will remain longer both in the environment and in the human body, which will modify the impact of radioactive materials on the environment and on health.