Repères - N°48 / March 2021 - The IRSN magazine - 7

JAPAN 2021

Using an open data device to measure radioactivity
at a storage facility for contaminated soil.

" Breast cancer, thyroid cancer, leukemia...
it's hard to say that these cancers are caused
by radioactive fallout, because the doses
received by the population were generally
low, just a few millisieverts, " Klervi Leuraud
summed up, who specializes in radiation-induced risk. Among epidemiologists,
this has been the consensus.
It cannot be denied there have been indirect
health effects, including diabetes, kidney
and liver failure, obesity and alcoholism,
but these are thought to result from disruption to healthcare services and
post-traumatic stress. Such stress is decreasing, as its prevalence fell by 19% in men
and 27% in women2 between 2012 and 2014.
n

In 2016, people displaced from the municipality
of Miharu, in Fukushima Prefecture, were still
living in temporary housing. Most of those who
remain are elderly, as many young people left
the region for good.

Decontamination work on a road
in Fukushima Prefecture, October 2016.

What about the
radiation-induced effects?

Four out of five residents have
not returned

Residents began to return to the area as of
April 1, 2014. Their return has been slow
and partial. At the beginning of 2020, the
average rate of return was below 20% for
all municipalities that had received orders
to evacuate, ranging from 2% to 75%.
n

The importance of " facilitators "

" The measurements made the radioactivity visible. " According to Jean-François
Lecomte, an expert in radiation protection,
this was one of the key insights resulting
from Fukushima Dialogue, a project backed
by IRSN and that gave a voice to Japanese
people affected by the accident since 2011.
Citizen initiatives developed to add to the
official measurements. A farmer in Suetsugi
monitored the radioactivity in his fields,
associations sourced the equipment needed
to take measurements, and residents called
for personal dosimeters. Discussion with
experts help everyone to gain a better
understanding of the situation. That is how

the idea of co-expertise came into being.
Another takeaway was that standards are
not enough. They can even be detrimental.
From 2011, to reassure the population, the
limits relating to the contamination of
foodstuffs were lowered. However, some
consumers believe that the limit is proof
of contamination.
What happened in Japan revealed the importance of " facilitators " , for example teachers
and medical or administrative staff who act
as intermediaries between citizens and the
authorities.
n

Contaminated water,
a real headache

In November 2020, there was 1,234,000
cubic meters of tritiated water stored in
1,040 tanks on the nuclear power plant
site. This radioactive water results from
ten years of cooling the damaged reactors.
According to TEPCO, the limit of
1,370,000 m3 will be reached in 2022.
In 2016, Japanese experts were looking at
various options. Of these, two are still on
the table and being discussed with stakeholders: discharge it into the sea (to dilute it)
or vaporize it into the atmosphere (as water
vapor). The technical, radiological and sociological advantages and disadvantages of
these options are being examined.
According to Japanese authorities, the
impact that discharging this water into
the sea would have on people and the environment is comparable to the impact of
nuclear facilities currently in service. n
1. The French National Radioactive Waste
Management Agency.
2. Fukushima Health Management Survey.

Find out more:

The Fukushima Dialogue Initiative
irsn.fr/Kotoba-EN

Nearly 170 m3 of tritiated water
are produced every day.

Page 7 - Repères No. 48 - March 2021

recycling as well as for sites or disposal
facilities outside Fukushima Prefecture.
The last remaining kariokiba will be
emptied by the end of 2021.
Decontamination has now been completed
within the Intensive Contamination Survey
Area (ICSA). This encompasses the Special
Decontamination Area and the municipalities where the estimated annual dose
was thought to be between 1 and 20 mSv.
" It will take many more years to manage
this waste, and it will be very costly, "
summed up Jérôme Guillevic, an expert
in radiation protection.

https://www.irsn.fr/Kotoba-EN

Repères - N°48 / March 2021 - The IRSN magazine

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