1. Is the Food in Japan Safe?
Talk given at the American Chamber of Commerce
Japan, Tokyo (starts 5:30pm, Tokyo)
by
Professor Wade Allison, Oxford
Professor Akira Tokuhiro, University of Idaho
3 October 2011
2. Professor Akira Tokuhiro
• Akira Tokuhiro, Ph.D.; tokuhiro@.uidaho.edu
• Professor of Nuclear and Mechanical Engineering
• Born in Tokyo, educated in the U.S.
• 20+ years of international nuclear engineering R&D, research,
teaching experience
• Tokuhiro and co-authors, Technical Lessons Learned from Fukushima,
Valve World, Oct 2011. Fukushima Dai-ichi: Initial Technical Lessons,
Nuclear Exchange, May 2011. Updated Technical Lessons Learned 100
Days After Quake, Tsunami at the Fukushima Dai-ichi, Units 1-6, Nuclear
Power Plant, July 2011.
• University of Idaho
• 1776 Science Center Drive
Idaho Falls, Idaho USA 83402
• T: +1- 208-533-8102
F: +1-208-526-8455
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4. Challenges in Short (assuming cold shutdown established)
Time: years to come
Expense: multi-year expenses
Technical: achievable; cleanup is larger scale than TMI; little
to no experience in Japan
Safety: aftershock possible, NPS degradation (weathering),
access difficult
Environmental : effluent release mitigation; onsite and offsite
mitigation, water & airborne effluents
Waste management: interim waste storage plan &
implementation in conjunction with or ahead of cleanup
Workforce: large workforce needed; need to monitor
exposure and post-exposure health
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5. Contamination map,
‘hot-spots’
Contamination is distributed
http://mdn.mainichi.jp/mdnnews/news/20110914p2a00m0na013000c.
5
html
7. Hotspots
Hot spot mapping is not being consistently done
throughout Japan yet. It needs to be and the results
need to be made public.
People exposed to hot spots need to be tested for
radiation exposure.
Some villages/cities will be taken off the lists, whereas
others will be added.
Clean-up (top soil removal) needs to happen
systematically to make areas safe.
Locations for safe redeployment of soil must be
established.
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8. Food Safety, Matter of Risk
Recent O157, O111
E-coli outbreak and
deaths at chain
restaurant
Eating ‘fugu’, at licensed
and unlicensed
restaurants
Hg-ladened tuna
Genetically-modified
corn, soy beans
http://www.google.com/imgres?q=mercury+in+tuna&um=1&hl=en&gl=us&tbm=isch&tbnid=S2a4j6FMeE8r6M:&imgrefurl=http://news.3yen.com/2010-04-26/death-metal-
sushi/&docid=CCTj8e3PCf8O5M&w=302&h=350&ei=222CTpifNc-
CsgLZp_iIDw&zoom=1&biw=1280&bih=568&iact=rc&dur=394&page=1&tbnh=139&tbnw=116&start=0&ndsp=19&ved=1t:429,r:3,s:0&tx=44&ty=79 8
9. What is Risk?
Risk is relative to the individual, the group, societal
subgroups and the country itself
Risk involves ‘perception of benefit’ vs. ‘perception of
risk’
Therefore, ‘benefit’ and ‘risk ’ are constantly at issue
Examples of risk:
•Eating fugu (puffer fish)
•Eating mercury-ladened fish or eating radiation-
ladened fish
•Smoking cigarettes and drinking alcohol
•Flying on commercial airline
•Driving or being a passenger in a car
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11. Risk and Resiliency
The biological make-up of the individual. Each of us can and
does accommodate toxins differently.
“Resiliency” broadly defined is the ability of the body to
accommodate and mitigate the negative health effects of
toxins to which one is exposed.
One tries to minimize risk; however, there is a different
degree of resiliency in each of us.
Health effects from ingested toxins may appear immediately
to many years later; all types of cancer can be cause by
exposure to toxins.
Sometimes, (low) risk and (high) resiliency is not enough to
overcome cancer; many times it is sufficient
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12. Metrics to Consider in Exposure to Radiation
Time(T): How long/how short is the exposure?
Number/magnitude(N): How large/small is the
amount of radiation?
Length/area(L, L x L): How large/small an area
is contaminated?
Energy (E): What is the energy of the ionizing
radiation?
Distribution(D): Where is contamination?
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13. Radiation and Reason, Akira Tokuhiro
There are many risks in daily life; while voluntary risk is
acceptable, involuntary is not; remember the personal balance
between perception of benefit vs. risk
There are many toxins that one ingests in today’s polluted word;
13% (2007, Wikipedia) of all world deaths are from cancer; don’t
single out radiation; human body has ability to accommodate
toxins; the body is resilient over a lifetime; each individual is
different; science does not understand everything
Radiation detection and measurement is well-developed but more
sensitivity means higher-end instruments; lower-end can be
misleading; I encourage confirmatory, independent measurement;
work with radiation detection & measurement experts
Health effects studies on children & women of child-bearing years
are very difficult to do; conservatism should not be ‘1/10th’; we
simply do not know the complete health effects
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14. http://ajw.asahi.com/article/0311disaster/opinion/AJ2011092810124
Radiation expert believes more food testing needed
– Prof. Emeritus, Ikuro Anzai
“…central government said it would
not allow food to reach the market
if it contained radiation that
exceeded provisional standards,
concerns are being raised as to
whether that promise is being kept.
The most important issue right
now is that the sense of trust
among consumers is being hurt. “
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15. Action Plan, Food Safety
For the individual
Fear is factor
Be vigilant; cross-check information
Learn ‘risk and resiliency’; “TLEDN”
Re-establish trust from all parties;
communication and substantiated
commitment
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16. Contact information
Dr. Akira Tokuhiro
Professor, Mechanical & Nuclear
Engineering
University of Idaho
1776 Science Center Drive
Idaho Falls, ID 834-2-1575 USA
+1-208-533-8102
www.if.uidaho.edu
17. Post-Fukushima, Anticipated questions
Radiation Discussion Points:
Q1:Hot spot mapping - At what point should evacuations still be considered A: per
hotspot maps (generally NW areas) if and when cleanup and remediation is to
take place and if annual dose (as set) is exceeded
Q2: Exposure on March 15 and March 21 - What were they exposed to and should
they be concerned? A: need to check list of radio-nuclides to assess whether
exposure is of concern (is there data, has it been announced?)
Q3: How long will decontamination take and how long for the plant to be
decommissioned? A: see previous slide for plant; site vs. off-site
Q4: What is the effect of long-term, low-level exposure? A4: Wade Allison will
address this.
Q5:How can people feel assured about exposure for children? A5: assurance is
not so much about science but fear of the unknown; regardless of the science,
parents may decide on the side of conservatism with respect to children.
Q6: Why is Iodine 131(8d)/Cesium134(2y)/137(30y) only measured and not other
radionuclides? A6: if other isotopes are present, in principle, they can be
measured. Iodine and cesium are volatile, Effects of I-131 may turn up as
thyroid cancer; Cs-134/137 accumulate in muscles – may be of concern. T, N of
exposure is key
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