Dealing with the Aftermath of a Nuclear Accident: Challenges, …€¦ · Dealing with the...
Transcript of Dealing with the Aftermath of a Nuclear Accident: Challenges, …€¦ · Dealing with the...
Abel J. González
Argentine Nuclear Regulatory Authority
�Av. del Libertador 8250; (1429)Buenos Aires, Argentina �+54 1163231758; � [email protected],[email protected]
Abel J. González
Argentine Nuclear Regulatory Authority
�Av. del Libertador 8250; (1429)Buenos Aires, Argentina �+54 1163231758; � [email protected],[email protected]
Dealing with the Aftermath of a Nuclear Accident:
Challenges, Lessons Learned, Solutions
Dealing with the Aftermath of a Nuclear Accident:
Challenges, Lessons Learned, Solutions
International Conference on Global Emergency Preparedness and Response
Organized by the International Atomic Energy Agency in cooperation withCTBTO, EC, Europol, FAO, ICAO, ILO, IMO, INTERPOL, OECD NEA, PAHO, UNEP, UNOOSA, WHO, WMO
IAEA Headquarters, Vienna, Austria, 19–23 October 2015
International Conference on Global Emergency Preparedness and Response
Organized by the International Atomic Energy Agency in cooperation withCTBTO, EC, Europol, FAO, ICAO, ILO, IMO, INTERPOL, OECD NEA, PAHO, UNEP, UNOOSA, WHO, WMO
IAEA Headquarters, Vienna, Austria, 19–23 October 2015
Objective
� To review:
�challenges presented by the aftermath of accidents; and
� lessons learned in dealing with this difficult problem.
� To explore holistic solutions to the problems.
� To review:
�challenges presented by the aftermath of accidents; and
� lessons learned in dealing with this difficult problem.
� To explore holistic solutions to the problems.
Caution
� My presentation will only deal with the aftermath
of accidents with radiological consequences;
namely, it will address sequelae, or protracted
consequences rather than immediate responses.
� My presentation will only deal with the aftermath
of accidents with radiological consequences;
namely, it will address sequelae, or protracted
consequences rather than immediate responses.
Content
1. Quandary
2. Mythology
� Myth of ‘contamination’
� Myth of ‘dose limits’
3. Status
� New recommendations and standards
� The 1 mSv/y conundrum
4. Future
5. Epilogue
1. Quandary
2. Mythology
� Myth of ‘contamination’
� Myth of ‘dose limits’
3. Status
� New recommendations and standards
� The 1 mSv/y conundrum
4. Future
5. Epilogue
QuandaryQuandary
Common denominators
� Large amounts of radioactive substances are deposited
and become present in the habitat and consumer products.
� Such presence is confusedly termed ‘contamination’.
� Simple questions are asked by the affected people.
� Large amounts of radioactive substances are deposited
and become present in the habitat and consumer products.
� Such presence is confusedly termed ‘contamination’.
� Simple questions are asked by the affected people.
Ambiguity in responses challenges the wellbeing of people!Ambiguity in responses challenges the wellbeing of people!
Main culprit: 137CsMain culprit: 137Cs
Release of 137CsChernobyl ~ 1017 Bq - Fukushima ~1016 Bq
Release of 137CsChernobyl ~ 1017 Bq - Fukushima ~1016 Bq
“Contamination” of:
•Land,
•Forests,
•Water,
•Foodstuff
•Consumer products
“Contamination” of:
•Land,
•Forests,
•Water,
•Foodstuff
•Consumer products
Picture of the aftermathPicture of the aftermath
‘Contamination’ colour code (137Cs)‘Contamination’ colour code (137Cs)
• Chernobyl
• Fukushima
• Chernobyl
• Fukushima
37-185 kBq/m2 185-555 kBq/m2 555-1480 kBq/m2 >1480 kBq/m2
1Ci/m2 → 10 rad/h – 1 Bq/m2 → 2.7 10-10 Sv/h
3700 Bq/m2 → 1 µSv/h = 8.76 mSv/y
422 Bq/m2 → 1 mSv/y ; 100 Bq/m2 → 0.24mSv/y = 10% nat.back.
1Ci/m2 → 10 rad/h – 1 Bq/m2 → 2.7 10-10 Sv/h
3700 Bq/m2 → 1 µSv/h = 8.76 mSv/y
422 Bq/m2 → 1 mSv/y ; 100 Bq/m2 → 0.24mSv/y = 10% nat.back.
Responding unambiguously to simple and
straightforward questions from the public
Responding unambiguously to simple and
straightforward questions from the public
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Is it safe for me
and my family
to live here?
Are we in danger!?Are we not in danger!?
16
Can we play
outdoors?
Is it safe
for us to
eat this
food?
I have been told that the food
is within the standards but
‘contaminated’, should I tell
this to my customers?
We were told this water is contaminated; shall we use it?
Why I am
permitted to drink
this water but not
to swim in it?
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Should I terminate
my pregnancy?
Is my child safe??
Why doses of 20 mSv/year are
permitted now, if doses above a ‘dose limit’ of 1 mSv/year
were prohibited before the accident?
After all, doses were low. Why I have been first evacuated, then relocated and now I
am virtually resettled here?
Mythology
(set of widely held but exaggerated or fictitious stories and beliefs)
Mythology
(set of widely held but exaggerated or fictitious stories and beliefs)
26
‘Contamination’ ‘Dose limit’
The myth of ‘contamination’
(the enemy of understanding)
The myth of ‘contamination’
(the enemy of understanding)
� The international definition of the term contamination is:
�presence of radioactive substances on surfaces, or
within solids, liquids or gases (including the body), or
�process giving rise to their presence in such places.
� However, the popular connotation ‘contamination’ is
impurity or danger.
� This connotation was not intended in its formal denotation.
(Confusedly, the term is also used less formally to refer to a quantity,
namely the activity on a surface, or per unit area)
� The international definition of the term contamination is:
�presence of radioactive substances on surfaces, or
within solids, liquids or gases (including the body), or
�process giving rise to their presence in such places.
� However, the popular connotation ‘contamination’ is
impurity or danger.
� This connotation was not intended in its formal denotation.
(Confusedly, the term is also used less formally to refer to a quantity,
namely the activity on a surface, or per unit area)
‘Contamination’ in Latin-based languages
� The meaning of ‘contamination’ is not presence:
our usage of the term is wrong!
� Contamination means made impure by exposure
to or addition of a poisonous polluting substance.
(The term is derived from the Latin contaminare that means ‘make
impure’, and it was used over the years to identify food that was
impure, i.e. poisoned, for religious purposes; e.g., non-kosher food).
� The meaning of ‘contamination’ is not presence:
our usage of the term is wrong!
� Contamination means made impure by exposure
to or addition of a poisonous polluting substance.
(The term is derived from the Latin contaminare that means ‘make
impure’, and it was used over the years to identify food that was
impure, i.e. poisoned, for religious purposes; e.g., non-kosher food).
Unsurprisingly, other languages have translated
‘contamination’ with the same wrong connotation
� In Chinese, it was translated as污染 , wūrǎn,
which is a combination of污, dirty, and染,tinted;
its connotation is tinted with dirt!.
� In Arab, it was translated as UVوث , talawwuth, a
worrying term having the connotation of infection!
� In Russian was translated as Загрязнение,
zagryazneniye, meaning impurity and defilement.
� In Chinese, it was translated as污染 , wūrǎn,
which is a combination of污, dirty, and染,tinted;
its connotation is tinted with dirt!.
� In Arab, it was translated as UVوث , talawwuth, a
worrying term having the connotation of infection!
� In Russian was translated as Загрязнение,
zagryazneniye, meaning impurity and defilement.
August 25th, 2015
The problem occurred in Japanese as wellThe problem occurred in Japanese as well
Contamination → 汚染 (osen)
� 汚→ fouling, dirt, filth
� 染→ dyed, tinted
汚染→ fouling with filth?
Contamination → 汚染 (osen)
� 汚→ fouling, dirt, filth
� 染→ dyed, tinted
汚染→ fouling with filth?
Regulating ‘contamination’Regulating ‘contamination’
Foodstuff
Water
Non edible
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Incoherence in drinking liquidsIncoherence in drinking liquids
++
++
= 10 Bq/l for 137Cs= 10 Bq/l for 137Cs
= 1000 Bq/l for 137Cs= 1000 Bq/l for 137Cs
37
Incoherence in non-edible vs. edibleIncoherence in non-edible vs. edible
++
++
= 100 Bq/kg for 137Cs= 100 Bq/kg for 137Cs
= 1000 Bq/kg for 137Cs= 1000 Bq/kg for 137Cs
Changing ‘contamination’ limitsChanging ‘contamination’ limits
Belarus
JapanJapan
• Rice, meat, vegetables, fish: 500 Bq/Kg → 100 Bq/Kg,
• Milk, milk-powder, infant-food: 200 Bq/Kg → 50 Bq/Kg
• Drinking water: 200 Bq/Kg → 10 Bq/Kg
• Rice, meat, vegetables, fish: 500 Bq/Kg → 100 Bq/Kg,
• Milk, milk-powder, infant-food: 200 Bq/Kg → 50 Bq/Kg
• Drinking water: 200 Bq/Kg → 10 Bq/Kg
The myth of ‘dose limit’The myth of ‘dose limit’
A ‘dose limit’ that may be exceeded?A ‘dose limit’ that may be exceeded?
In normal language, ‘dose limit’ would be
understood as a point beyond which doses may not
pass, a terminal point or boundary for doses, the
furthest extent of endurance to radiation exposure.
In normal language, ‘dose limit’ would be
understood as a point beyond which doses may not
pass, a terminal point or boundary for doses, the
furthest extent of endurance to radiation exposure.
• Nobody can understand that a situation is safe, if
doses are higher than the ‘dose limit’
• Nobody can understand that a situation is safe, if
doses are higher than the ‘dose limit’
The Japanese expression for ‘dose limit’, is unequivocal:
線量限度
Senryō gendo
線→radiation beam,量→amount,限→limit,度→time
‘limit of the amount of radiation dose incurred in the time'
The Japanese expression for ‘dose limit’, is unequivocal:
線量限度
Senryō gendo
線→radiation beam,量→amount,限→limit,度→time
‘limit of the amount of radiation dose incurred in the time'
44
Summary history of the 5mSv/y
45
Shaky Start
(rule of thumb)
Risk ofradiationexposure
Reasonable but arbitrary decisionPublic one order of magnitude lower = 5mSv/y
50mSv/yRisk of
non-radiationworkers
5 mSv/y
ICRP
Statement from the 1987 Como Meeting of the ICRP.Annals of the ICRP 17(4), i-v (1987).
Statement from the 1987 Como Meeting of the ICRP.Annals of the ICRP 17(4), i-v (1987).
Summary history of the 1mSv/y
48
Workers 50mSv/yPublic 5mSv/y
ReevaluationHiroshima
&Nagasaki
doses
Workers 20mSv/y ??Public 1mSv/y
Factor 5 lower
1 mSv/y
ICRP
Summary logic of the 1mSv/y ‘dose limit’
1. The risk of ‘safe’ industries 0.4 10-4/y-1.5 10-4/y
2. The radiation risk factor → 1%/Sv
3. Occupational limit = 50 mSv/y
4. Public limit (one order of magnitude lower) = 5mSv/y
5. Hiroshima reevaluation → risk = 5%/Sv
6. New limits:
� Public limit = 1mSv/y
� Occupational limit = 20mSv/y ???
1. The risk of ‘safe’ industries 0.4 10-4/y-1.5 10-4/y
2. The radiation risk factor → 1%/Sv
3. Occupational limit = 50 mSv/y
4. Public limit (one order of magnitude lower) = 5mSv/y
5. Hiroshima reevaluation → risk = 5%/Sv
6. New limits:
� Public limit = 1mSv/y
� Occupational limit = 20mSv/y ???
In conclusione.1 mSv/y is neither the thesis of a theorem nor a dogma of faith.
It is reasonable to question its application!It is reasonable to question its application!
51
StatusStatus
New Recommendations
A new concept: reference levels for emergency or existing controllable exposure situations
� Level of dose above which it is judged to be
inappropriate to plan to allow exposures to occur.
(The chosen value will depend upon the prevailing circumstances of the exposure under consideration)
� Level of dose above which it is judged to be
inappropriate to plan to allow exposures to occur.
(The chosen value will depend upon the prevailing circumstances of the exposure under consideration)
Reference levels bands (mSv)
Characteristics of the situation
Protection
requirements
>20 to 100
Sources notcontrollable, or
protective actionsdisproportionately
disruptive
Reduce doses approaching 100 mSv.
Information and assessment of individual
doses.
>1 to 20
Individuals receive benefit from a controllable
exposure situation
Same
1 or less
Individuals exposed to a source that gives them little or no individual benefit but benefits society.
Periodic checks on the
exposure pathways as to
the level of exposure
New Standards
2 November, 2015 60
The EC BSS subtle difference
� In an existing exposure situation, "reference level"
means, the level of effective dose or equivalent
dose or activity concentration above which it is
judged inappropriate to allow exposures to occur
as a result of that exposure situation, even though
it is not a limit that may not be exceeded.
� In an existing exposure situation, "reference level"
means, the level of effective dose or equivalent
dose or activity concentration above which it is
judged inappropriate to allow exposures to occur
as a result of that exposure situation, even though
it is not a limit that may not be exceeded.
Have they solved the issues of the aftermath?Have they solved the issues of the aftermath?
The questions continue to be:
� Are we safe or not?
� Why doses of 20 – 100 mSv/year are permitted
after an accident when doses above a ‘dose limit’ of
1 mSv/year were prohibited before the accident?
� Are we safe or not?
� Why doses of 20 – 100 mSv/year are permitted
after an accident when doses above a ‘dose limit’ of
1 mSv/year were prohibited before the accident?
The 1 mSv/y conundrumThe 1 mSv/y conundrum
Confusion with 1 mSv/y (an old saga)Over the years there has been confusion over the meaning of the dose limit of 1mSv/y.
� 1 mSv/y applies to doses from deliberate endeavors and,
within these, from sources that can be controlled.
� 1 mSv/y is lower than the dose from extant sources, many
of which are natural sources that cannot be controlled.
� This position is not easily explainable!
� Extant doses do not necessarily justify adding doses from
controllable sources.
� Is it proper to control these sources, even if their doses are
less than the extant background doses?
� Does the extant background provide a basis to judge?
� 1 mSv/y applies to doses from deliberate endeavors and,
within these, from sources that can be controlled.
� 1 mSv/y is lower than the dose from extant sources, many
of which are natural sources that cannot be controlled.
� This position is not easily explainable!
� Extant doses do not necessarily justify adding doses from
controllable sources.
� Is it proper to control these sources, even if their doses are
less than the extant background doses?
� Does the extant background provide a basis to judge?
Application of the Commission's Recommendations to the Protection of People Living in Long-term Contaminated Areas After a Nuclear Accident or a Radiation
Emergency. ICRP Publication 111. Ann. ICRP 39 (3).
ICRP 111 Dictum
� §(bb) Past experience e.(Bikini, Maralinga), nuclear accidents (Kyshtym, Palomares, Chernobyl),..(Goiânia) illustrates the potential importance of ingestion of contaminated foodstuffs eeAs far as the setting of reference levels for existing exposure situationsee., past experience shows that typical dose values selected by authorities to manage such situations are close or equal to 1 mSv/year, corresponding to the desire to progressively reduce long-term exposure to levels that are close or similar to situations considered ‘normal’, i.e within the band of constraints set for public exposure in planned situations.
� §(bb) Past experience e.(Bikini, Maralinga), nuclear accidents (Kyshtym, Palomares, Chernobyl),..(Goiânia) illustrates the potential importance of ingestion of contaminated foodstuffs eeAs far as the setting of reference levels for existing exposure situationsee., past experience shows that typical dose values selected by authorities to manage such situations are close or equal to 1 mSv/year, corresponding to the desire to progressively reduce long-term exposure to levels that are close or similar to situations considered ‘normal’, i.e within the band of constraints set for public exposure in planned situations.
Is 1 mSv/y a logical ‘dose limit’?Is 1 mSv/y a logical ‘dose limit’?
Namely, a border beyond which individual doses
shall not pass under any circumstance?
Namely, a border beyond which individual doses
shall not pass under any circumstance?
� No logical arguments sustain this dogma.
� All over the world, people incur additional
1 mSv/y (and more) by just changing the place
where they live and nobody considers this as a
radiation protection issue.
� No logical arguments sustain this dogma.
� All over the world, people incur additional
1 mSv/y (and more) by just changing the place
where they live and nobody considers this as a
radiation protection issue.
No, 1 mSv/y shall not be regarded as a border
beyond which individual doses must not pass
Is 1 mSv/y a sensible value for
restricting additional doses
committed by individuals due to
controllable endeavors, e.g., a
continuously expanding activity?
Is 1 mSv/y a sensible value for
restricting additional doses
committed by individuals due to
controllable endeavors, e.g., a
continuously expanding activity?
� If not, endeavors such as a massive expansion
of the generation of nuclear electricity could
become unsustainable.
� If not, endeavors such as a massive expansion
of the generation of nuclear electricity could
become unsustainable.
Yes, 1 mSv/y may be regarded as a sensible restriction for continuous activities
committing people to radiation exposure
2 November, 2015 73
Doses after 1 year of operation
D
t1st year 2ndyear
3rd year e. e e. nth year
2 November, 2015 74
Doses after 2 years of operation
D
t1st year 2ndyear
3rd year e. e e. nth year
2ndyear
3rdyear4thyear
e.e
e.
2 November, 2015 75
Doses after 3 years of operation
D
t1st year 2ndyear
3rd year e. e e. nth year
2ndyear
3rdyear4thyear
e.e
e.
3rd year
4th year
5th yeare.
e
2 November, 2015 IRPA11: Sievert Lecture 76
EQUILIBRIUM = ∫ first year committment
IRPA11: Sievert Lecture 77
Bo Lindell:
“Radiation and Man”
1973 Sievert Lecture
IRPA 3: Washington DC, USA
2 November, 2015 78
TodayToday
TomorrowTomorrow
2 November, 2015 79
If today’s nuclear electricity generation expands , in order to
restrict future doses, it would be necessary to limit the doses
committed over time by unit practice,
i.e. to limit
the collective dose commitment
per unit energy of nuclear-electricity produced.
If today’s nuclear electricity generation expands , in order to
restrict future doses, it would be necessary to limit the doses
committed over time by unit practice,
i.e. to limit
the collective dose commitment
per unit energy of nuclear-electricity produced.
For this purpose 1 mSv/y would be a
reasonable restriction
� Because it will imply a sensible control of a large
expansion of nuclear power, whereby people would
– even in the long term – not incur additional doses
higher than a fraction of typically elevated
background doses.
� Because it will imply a sensible control of a large
expansion of nuclear power, whereby people would
– even in the long term – not incur additional doses
higher than a fraction of typically elevated
background doses.
2 November, 2015 80
However, this and other logical uses of
a 1 mSv/y dose restriction,
should not imply that 1 mSv/y is a
demarcation between safe and unsafe!
However, this and other logical uses of
a 1 mSv/y dose restriction,
should not imply that 1 mSv/y is a
demarcation between safe and unsafe!
The FutureThe Future
If a problem persists,
perhaps the problem is ourselves!
If a problem persists,
perhaps the problem is ourselves!
We need a bath of humility!
� The time is ripe to recognize that there is a
problem with the myriads of:
→ dose reference levels and
→ Bq/m3’s,
e..and particularly with the 1 mSv/y!
� The time is ripe to recognize that there is a
problem with the myriads of:
→ dose reference levels and
→ Bq/m3’s,
e..and particularly with the 1 mSv/y!
Errare humanum est,
perseverare autem diabolicum
(To err is human; to persist in committing such errors is of the devil)
Errare humanum est,
perseverare autem diabolicum
(To err is human; to persist in committing such errors is of the devil)
We have to stop following classical routes.
Science and society have changed and it is
our obligation to respond to the demands of
the people we want to protect.
We have to stop following classical routes.
Science and society have changed and it is
our obligation to respond to the demands of
the people we want to protect.
Wolfgang WeissWolfgang Weiss
The radiological protection community has an ethical duty to
learn from the lessons and resolve identified challenges.
Before another large accident occurs, it should be ensured
that:
�Radiation risk and potential effects are properly interpreted;
e.
�Recommendations on public protection levels are consistent.
.....
�Acceptable ‘contamination’ levels are clearly defined.
ee
�Failures in fostering information sharing on protection policy
after an accident is addressed with recommendations to
minimize lapses in communication.
The radiological protection community has an ethical duty to
learn from the lessons and resolve identified challenges.
Before another large accident occurs, it should be ensured
that:
�Radiation risk and potential effects are properly interpreted;
e.
�Recommendations on public protection levels are consistent.
.....
�Acceptable ‘contamination’ levels are clearly defined.
ee
�Failures in fostering information sharing on protection policy
after an accident is addressed with recommendations to
minimize lapses in communication.
Challenging the status quo
KBq/m2
1000000
100000
10000
1000
100
Lognormal probability distribution of 134Cs + 137Cs activity concentration
in mushrooms during the 12 months after the accident
EpilogueEpilogue
A few humble suggestions to solve the conundrum
A few humble suggestions to solve the conundrum
(1) Let us abandon the language stating that
1 mSv/y is a ‘dose limit’
(1) Let us abandon the language stating that
1 mSv/y is a ‘dose limit’
(2) State unambiguously that it is not
scientifically feasible to attribute
retrospectively health effects to doses of
around 1mSv/y
(2) State unambiguously that it is not
scientifically feasible to attribute
retrospectively health effects to doses of
around 1mSv/y
(3) Explain why it is reasonable to restrict to
1 mSv/y the additional committed doses
from a continuously increasing activity, such
as the generation of nuclear energy
(3) Explain why it is reasonable to restrict to
1 mSv/y the additional committed doses
from a continuously increasing activity, such
as the generation of nuclear energy
(4) Unequivocally define protracted radiological
aftermaths as extant exposure situations, namely a
set of circumstances delivering low radiation
exposures which are already in existence when a
decision on control has to be taken.
(4) Unequivocally define protracted radiological
aftermaths as extant exposure situations, namely a
set of circumstances delivering low radiation
exposures which are already in existence when a
decision on control has to be taken.
(5) Search for international consensus for
levels of activity that can be deemed to be
‘safe’ without any further consideration and
which, therefore, may be exempted from any
regulatory control
(5) Search for international consensus for
levels of activity that can be deemed to be
‘safe’ without any further consideration and
which, therefore, may be exempted from any
regulatory control
I would like to share with you a basic doubt
Is the dosimetric approach appropriate for
extant situations of public exposure to low
radiation doses?
Is the dosimetric approach appropriate for
extant situations of public exposure to low
radiation doses?
A simple (rather than simplistic) proposal
Exempt any situation where the activity
density and concentration of 137Cs are:
< 100 KBq / m2
< 0.1 KBq / Kg
(Perhaps also include exemptions of:� one order of magnitude less for 131I and 90Sr and
� two orders of magnitude less for 241Am, 238Pu and 239Pu)
Exempt any situation where the activity
density and concentration of 137Cs are:
< 100 KBq / m2
< 0.1 KBq / Kg
(Perhaps also include exemptions of:� one order of magnitude less for 131I and 90Sr and
� two orders of magnitude less for 241Am, 238Pu and 239Pu)
Communication!
The radioactive cesium on land and in consumer products is lower than the international safe values of 100 KBq/m2 and 100 Bq/Kg. We confirm that THE SITUATION IS SAFE.
(Hurrah!!!, 139 characters!!!!)
[email protected], [email protected]
+5441163231306
Av. del Libertador 8250Buenos Aires, Argentina
Thank you!Thank you!