External radiation doses in Fukushima comparable to those of Europe: study

by

Staff Writer

The external radiation exposure levels of high school students in Fukushima Prefecture are within the same range of those living in France, Poland and Belarus, a scientist and a high school student said Monday in Tokyo.

Both were among members of a research group that conducted a study on individual radiation levels.

Speaking at the Foreign Correspondents’ Club of Japan, Ryugo Hayano, a professor in the University of Tokyo’s physics department, said that while the effect of the 2011 meltdowns at the Fukushima No. 1 nuclear plant definitely remains, radiation levels have fortunately lowered over the past five years.

Because natural background radiation levels in Fukushima are lower than the world’s average, even when the extra radiation dose from the nuclear disaster is added, the external exposure of Fukushima residents did not differ significantly from those measured in other parts of the world, they said.

The study does not include the evacuation zone around the crippled plant.

Initiated by a group of students at Fukushima High School, the study examined 216 students and teachers in 12 high schools — six in Fukushima and six in other prefectures such as Kanagawa and Nara — and compared the results with eight schools in Poland, four in France and two in Belarus for two weeks in 2014.

Each participant wore a personal electronic dosimeter and kept a journal of their activities.

According to the study, published in the Journal of Radiological Protection last November, the external doses received by participants in Fukushima during the two-week period were “well within the terrestrial background radiation levels of other regions or countries.”

The median annual external radiation exposure of students in Fukushima was estimated to be 0.63 to 0.97 millisieverts, compared with 0.51 to 1.10 in Poland, France and Belarus, according to the study.

“I wanted to know how high my exposure dose was and wanted to compare that with people in other places,” said Haruka Onodera, a student at Fukushima High School.

Although she knew nothing about external radiation at the start of the examination, through analyzing and collecting data, Onodera said she was able to deepen her understanding and realized the importance of evaluating risk based on objective scientific facts.

The International Commission on Radiological Protection (ICRP) sets recommended annual radiation exposure limits under normal situations at 1 millisievert. A cumulative dose of 100 millisieverts over a lifetime would increase the chance of developing cancer by 0.5 percent, according to the ICRP.

The average terrestrial natural radiation level in Japan is around 0.33 millisieverts per year, the report said, which is lower than the world average of 0.48 millisieverts.

  • TV Monitor

    Why won’t Japan let private citizens post their own radiation readings online then? What is there to hide? Plenty of course.

    • Starviking

      Do you have any evidence for your assertion that the Japanese government is preventing Japanese citizens from freely using the internet?

    • Starviking

      Do you have any evidence for your assertion that the Japanese government is preventing Japanese citizens from freely using the internet?

    • Ken Yasumoto-Nicolson

      You’ll find that Safecast has most than enough private Japanese citizens posting readings.

  • Roy Warner

    Poland, France, and Belarus sadly have more than “natural” background radiation levels with which to contend, as they were hit by Chernobyl. Perhaps that is why they were chosen for this study. What is the level of internal exposure experienced by Fukushima children?

    • Sam Gilman

      Roy,

      Have you ever thought of using Google to find out answers to these questions? It’s just that when you raise such questions without making any effort to answer them, it does looks abut like you’re just trying to stoke fears for sport.

      Internal and external doses have been assessed. No dangerously high doses have been found. This is not difficult to find.

      http://www.rrjournal.org/doi/abs/10.1667/RR13351.1

      The study mentioned here is available online.

      http://iopscience.iop.org/article/10.1088/0952-4746/36/1/49;

      Two of the three schools in France were in the west. You can search for Chernobyl fallout maps for France. You can see that there was no fallout to speak of in the west at all. In any case, twenty years after Chernobyl, the effects even in the most contaminated parts of France fell from 1mSv/yr extra to 0.01mSv extra. Here’s a map of caesium fallout over Europe:

      http://www.bibliotecapleyades.net/imagenes_ciencia/uranium33_05.jpg

      Indeed, if you’d looked up the study, you could have read the rationale for the choice of areas:

      In France and Poland, the high schools involved in the study participated on a voluntary basis without specific selection. In France, the four high schools are located in three different regions characterized by a range of natural terrestrial radiation background level, the lowest level being observed in Boulogne (closed to Paris) while higher value is observed in Corsica (see Figure 3). In Poland, the location of the schools is also ranging from lower values for high schools in the region of Warszawa to the highest in Zabrze (see figure 4).

      Two high schools from Belarus were involved due to their location in the Gomel region, impacted by the fallout of the Chernobyl accident. The first high school is located in Gomel City while the second one is located close to the exclusion zone (in Bragin district) and thus characterized by a higher ambient radiation dose rate (see figure 5).

      So yes, Belarus has areas with raised rates of radiation from Chernobyl, but that was the point of those places being chosen.

      Google scholar in particular is a wonderful tool giving people access to independently assess the science. You should use it.

      • Bradley Fried

        You can answer a question without being snarky.

      • Sam Gilman

        I wasn’t snarky. I was asking someone who lives here to take responsibility for what they say.

        You may not be aware of this, but there are people who don’t care what is actually happening in Fukushima, but instead have a kind of pornographic obsession with the idea that a nuclear power station has killed people.

      • Bradley Fried

        It hasn’t killed people with radiation, but it has destroyed lives and hundreds of deaths have been attributed to the stress and health consequences of lost homes, lost lives, lost income, etc. from the evacuation.

        I am well aware of the fringes on both sides of the nuclear debate and the fake Fukushima stories put out by the-sky-is-falling nut cases and pro-nuclear fetishists as well.

        That over a hundred thousand people are still displaced and have been savaged emotionally and financially by TEPCO and the government because of the nuclear agenda is to me the most damning argument against nuclear power in Japan.

      • Sam Gilman

        If you accept that the radiation leaks are unlikely to result in any direct harm, and that health problems are from psychological and social stress from fear and displacement, then we are on at least the same page. We can agree on basic facts like this. Neither of us is part of the fringe on health. That’s important.

        Where we disagree is that I think the analyses should not stop at blaming TEPCO for failing to maintain Fukushima Daiichi properly, although that is of course a very important issue. We also need to look at the response once the releases happened – on the part of the government and on the part of the media, NGO groups and activists. It is the response that has caused the health problems, not the leaks themselves. We need to ask serious questions about the manner, extent and duration of evacuations, for example, or the management of radiation safety standards.

        In particular, campaigns by activists, aided by certain elements in the media, to disempower the population of Fukushima by providing false information about risk, by campaigning to undermine authoritative sources of public health information and by the targeting of parents (particularly mothers, who are generally most vulnerable to fearmongering) must be condemned. These are not people handling matters incompetently. These are not people who just happen to lack a bit of scientific knowledge. They are a direct threat to public health, in the same manner that anti-vaxxers are. They’ll even dismiss Safecast if it suits them.

        Arguments for and against nuclear power are a separate issue (which involves assessment of alternatives and of climate change). I see from your Disqus feed that you are indeed very anti-nuclear. However, on this issue of the welfare of people in Fukushima prefecture and the spread of good health information and maintaining trust in it, surely it’s important not to be caught up in tribalism, or exploit the fruits of these nasty labours for political gain.

      • Bradley Fried

        It hasn’t killed people with radiation, but it has destroyed lives and hundreds of deaths have been attributed to the stress and health consequences of lost homes, lost lives, lost income, etc. from the evacuation.

        I am well aware of the fringes on both sides of the nuclear debate and the fake Fukushima stories put out by the-sky-is-falling nut cases and pro-nuclear fetishists as well.

        That over a hundred thousand people are still displaced and have been savaged emotionally and financially by TEPCO and the government because of the nuclear agenda is to me the most damning argument against nuclear power in Japan.

      • QuibONO

        Propaganda for the too busy, gullible & willfully ignorant lazies.

  • Leo Pelliccia

    Load of crap.

  • Joffan

    Stop spreading your nonsense scare stories; it’s anti-science and anti-human.

    There are zero additional deaths expected from cancer due to Fukushima, in the general population. Chris Busby’s fake websites notwithstanding. The Yablokov Greenpeace anti-nuke propaganda has been thoroughly trashed by all reviewers, who recognize that it throws any deaths into the mixer without regard for relevance. Claiming the United Nations as part of your conspiracy theory just illustrates how far you are from reality.

  • Brian

    Move along folks, tobacco is good for ya, I mean radiation.