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‘ Late lessons from early warnings the precautionary principle
1896-2000’
David Gee, Coordinator, Emerging Issues and Scientific Liaison, EEAEuropean Parliament Meeting, Dec 11th ,2003
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EEA’s main Tasks• To provide the Community and member
countries with information needed to: identify, frame, prepare and implement sound
and effective environmental policy measures monitor, evaluate and disseminate actual and
expected results of such measures to clients and the public
• To establish and coordinate the European environment information and observation network (EIONET), for the collection, assessment and sharing of data with European Commission services, EEA member countries and international organisations.
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“Wisdom is to know,
that you do not know”
(Socrates)
An early lesson, lately forgotten?
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Chemicals – the dearth of data
EEA draft
• ToxicityOf 2,500 high production volume chemicals, only 14 % have sufficient data for a minimal OECD risk assessment
• ExposureThere is very little data on exposure levels for ecosystems and people, particularly sensitive groups (e.g. children)
• External environmental costsLittle data – but the costs of ill health, environmental damage, fires/explosives, etc., are large–and can be reduced by getting market prices & the regulatory framework right
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Measuring is Not Knowing:The Marine Environment and the Precautionary Principle
“The enormous number of papers in the marine environment means that huge amounts of data are available, but …we have reached a sort of plateau in …the understanding of what the information is telling us …. We… seem not to be able to do very much about it or with it. This is what led to the precautionary principle, after all – we do not know whether, in our studied ecosystem, a loss of diversity would matter, and it might”.
Marine Pollution Bulletin, Vol 34, No. 9, pp. 680-681, 1997
Context 1
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The precautionary Principle: The working definition used in the
“Late Lessons” Report
“A general rule of public policy action to be used in situations of potentially serious or irreversible threats to health or the environment, where there is a need to act to reduce potential hazards before there is strong proof of harm, taking into account the likely costs and benefits of action and inaction”
(Source: “Late Lessons” Report, Introduction, p. 13)
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The Precautionary Principle is:
1. NOT a prediction- it is a process that may/may not lead to exposure reduction measures.
2. NOT the same as “prevention” which is concerned with “known” risks”.
“Precaution” = Uncertain/unknown hazards/risks. Eg.bans on asbestos or
smoking in 1950/60s would have involved both Precaution and Prevention
but bans in 2003 are Prevention only because risks are well known. (See
“Late Lessons”, P192)
3. NOT based on “zero risks” but aims to achieve lower/more acceptable
risks/hazards with lower overall costs, both quantifiable and non-
quantifiable.
4. NOT proof against mis-use or bad decision making (as with any other
policy tool).
5. NOT same as “risk assessment”: it is broader, deeper, supplementary
to R.A.
“Towards a Common Understanding of the Precautionary Principles”
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6. NOT oblivious of costs of all kinds, and in both directions (i.e. of
acting or not acting to reduce risks/hazards), including “secondary”
costs/benefits.
7. NOT one sided – it applies to substitutes/alternatives too: and it
promotes innovation and combats monopolies such as asbestos, CFCs,
PCBs, antibiotics in animal feed, etc.
8. NOT based on anxiety/emotion- but uses the best of the “systems
sciences” of complex processes to make, hopefully,wiser decisions.
9. NOT a guarantor of “consistency” or “predictability” between
cases – each case is different/ has different facts. (as with legal cases)
10. NOT affected by people’s motives for promoting/opposing the PP –
but their “interests”(economic, political, scientific) in the issue do need
declaring.
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Late Lessons: An Analysis of 14 ”False Negative” Case Studies
”False Negatives” = Whoops! It really is dangerous after all!
“False Positives” = Whoops! It really isn’t dangerous after all!
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Why So Many ”False Negatives”?
• ”Sound science” generates more false negatives than false positives (= good science but poor public policy)
• Short term economic/political interests can dominate longer term, total welfare interests.
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‘Late Lessons’ is based on case studies
Structured around 4 questions:• When were the first scientifically based
early warnings ? • When and what were the main
actions, or inactions, by society’s actors ?
• What were the costs and benefits (all kinds) of the actions/inactions; and
• What lessons can be drawn that may help improve decisionmaking and reduce overall costs ?
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What about ”False Positives”?
• Harder to prove
• Failed to find authors for them
• “Secondary Benefits” often make them worthwhile eg. Y2K “bug”
• Vol 2 of “Late Lessons” will have a “false Positive” chapter
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Antimicrobial Feed Additives (AFA) Chapter – An “Early
Warning” example: 1969 – UK Medical Research Council’s Swann Committee:
• ‘Despite the gaps in our knowledge .. We believe … on the basis of evidence presented to us, that this assessment is a sufficiently sound basis for action .. The cry for more research should not be allowed to hold up our recommendations’
• ‘Sales/use of AFA should be strictly controlled” via tight criteria, despite not knowing mechanisms of action, nor foreseeing all effects’
• ‘More rewarding to improve animal husbandry than to feed diets containing AFA’
Source: (HMSO, UK, Nov. 1969)
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CFCs Chapter: Skin Cancer and Time Lags
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Twelve Late Lessons fromEarly Warnings
A ”Identify/Clarify the Framing and Assumptions”
1. Manage “risk”, “uncertainty” and “ignorance”2. Identify/reduce “blind spots”3. Assess/account for all pros and cons4. Analyse/evaluate alternative options5. Take account of stakeholder values6. Avoid “paralysis by analysis” by acting to
reduce hazards via the precautionary principle.
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Towards A Clarification of Key TermsSituation State and dates of
knowledgeExamples of action
Risk ‘Known’ impacts; ‘known’ probabilities e.g. asbestos
Prevention: action taken to reduce known hazards e.g. eliminate exposure to asbestos dust
Uncertainty
‘Known’ impacts; ‘unknown’ probabilities e.g. antibiotics in animal feed and associated human resistance to those antibiotics
Precautionary prevention: action taken to reduce exposure to potential hazards
Ignorance ‘Unknown’ impacts and therefore ‘unknown’ probabilities eg the ‘surprises’ of chlorofluorocarbons (CFCs) and asbestos mesothelioma cancer
Precaution: action taken to anticipate, identify and reduce the impact of ‘surprises’
Source: ‘Late Lessons’, page 192
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How Can We Respond to“Ignorance” (“Surprises”)?
1. Use intrinsic parameters as proxies for unknown but possible impacts (e.g. persistence and/or bioaccumulation potential of chemical substances. (See Case Studies on PCBs, MTBE, CFCs, TBT)
2. Reduce specific exposures to potentially harmful agents on the basis of credible ‘Early Warnings’ of initial harmful impacts (thus limiting the size of any other ‘surprise’ impacts from the same agent, e.g. the asbestos cancers that followed asbestosis; and PCB neurotoxicological effects that followed wildlife impacts). (See 5 other responses to “ignorance” in “Late Lessons” supplementary report, EEA 2003)
3. Promote a diversity of robust and adaptable technological and social options to meet needs (which limits technological ‘monopolies’ such as asbestos, CFCs, PCBs etc., and therefore reduces the scale of any ‘surprise’).
EEA draft
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• Including their distribution; and ‘secondary’ benefits and costs
• Include effects of innovation and technological change, as well as social impacts of technology choices
• Product prices to include full costs of production, use & disposal (the 'polluter pays principle')
• This maximises efficiency, stimulates innovation and minimises environmental and health burdens
• Precautionary costs should not greatly outweigh the benefits; the proportionality principle
Lesson 3: Assess, justify and
account for all pros and cons
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• Avoid Substance ‘monopolies’ that stifle innovation (see Asbestos, CFCs, PCBs, AFA)
• Stimulate available alternatives (see antimicrobials, asbestos, radiation, CFCs)
(The principle of substitution, now part of OSPAR’s Strategy on Hazardous Substances requires a comparative assessment of alternative means of providing services; as does the EU Biocides Directive)
• But use precaution, eco-efficiency and diversity with substitutes, too
Lesson 4: Evaluate alternative means of providing services
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(CONT.)
B ”Broaden Assessment Information”7. Identify/reduce interdisciplinary obstacles
to learning8. Identify/reduce institutional obstacles to
learning9. Use “lay”, local and specialist knowledge10.Identify/anticipate “real world” conditions11.Ensure regulatory and informational
independence12.Long term monitoring/research
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“Misplaced certainty about the absence of harm played a key role in delaying preventive actions in most of the case studies”
(Preface, ‘Late lessons from Early Warnings: the Precautionary Principle 1896-2000’)
Less Hubris, more Humility?
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ON BEING WRONG: Environmental and Health Sciences and Their
Directions of Error
1 Some features can go either way (e.g.inapproriate controls) but most of the features mainly err in the direction shown in the table
SCIENTIFIC STUDIES
SOME METHODOLOGICAL FEATURES
MAIN1 DIRECTIONS OF ERROR-INCREASES CHANCES OF DETECTING A:
Experimental
•High doses •False positive
Studies •Short (in biological terms) range of doses
•False negative
(Animal •Low genetic variability •False negative
Laboratory) •Few exposures to mixtures •False negative
•Few Foetal-lifetime exposures
•False negative
•High fertility strains •False negative (Developmental/reproductive endpoints)
EEA draft
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Observational
•Confounders •False positive
Studies •Inappropriate controls •False positive/negative
(Wildlife & •Non-differential exposure misclassification
•False negative
Humans) •Inadequate follow-up •False negative
•Lost cases •False negative
•Simple models that do not reflect complexity
•False negative
Both •Publication bias towards positives
•False positive
Experimental
And
•Scientific cultural pressure to avoid false positives
•False negative
Observational
Studies
•Low statistical power (e.g. From small studies)
•False negative
•Use of 5 % probability level to minimise chances of false positives
•False negativeEEA draft
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Levels of proof - some examples
• Beyond all reasonable doubt
• Reasonable certainty
• Balance of probabilities/evidence
• Strong possibility
• Scientific suspicion of risk
• Negligible/insignificant
EEA draft
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Endocrine Disrupting Substances (EDSs):Some difficult features
• Timing of the dose• Mixtures• Natural and synthetic EDSs• ”Hormonal imprinting”• Endocrine systems ”cross-talk”• Generational impacts• Impacts/Adverse impacts • Adverse impacts due to imbalance
between opposing affects in complex systems
EEA draft
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It’s the Timing of the Dose that Makes the Poison for
Developmental and Reproductive Harm
• ”The time of life when exposures take place may be critical in defining dose-response relationships of EDSs for breast cancer as well as for other health effects” (WHO/IPCS ”State of the Science of EDSs”, 2002)
• DES• DDT• TBT• Thalidomide• Etc.
EEA draft
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”TBT Antifoulants: A Tale of Ships, Snails and Imposex”
(Chapter 13)• An increased appreciation of
scientific complexity and indeterminacy accompanied the unfolding of the TBT impacts story.
• Very low doses caused adverse impacts (i.e. in parts/trillion)
• High exposure concentrations were found in unexpected places e.g. the marine microlayer
EEA draft
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Towards a Clarification of Some Key Terms: From ”Association” to ”Causation” and ”Mechanisms of
Action”Situation
“Association”
Relevant Information
Some weak to strong evidence linking an environmental and/or health impact with a stressor
(“We see that X may cause Y”)
Time to produce relevant information
Weeks to years
Years to decades
EEA draft
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Situation
“Causation”
“Mechanisms of Action”
Relevant Information
Substantial evidence and knowledge linking impacts with stressor(“We know that X causes Y”)
Substantial evidence and knowledge and understanding of the reasons why there is a causal link between an impact and a stressor(“We understand why X causes Y”)
Time to produce relevant information
Years to decades
Usually Decades
EEA draft
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Applying the Precautionary Principle:
Key Decisions1. Assigning burdens of proof2. Evaluating the evidence (in a
framework)3. Choosing appropriate level of proof4. Evaluating the justification / need5. Assessing alternatives6. Assessing appropriate policy measures7. Taking transparent decisions8. Involving stakeholders in all stages
EEA draft
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“Man has lost the capacity to foresee and forestall....he will end up destroying the earth.”
- Albert Schweitzer
Will this prediction come true ?
Or could the precautionary principle help us to foresee and forestall Hazards… using the best of systems science whilst stimulating innovation?
EEA draft
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Multi-causality and Complexity
HOST GENETICS
HOST STATE EXPOSURES/DOSES EFFECTS
•Genotypes and phenotypes
+ + = =>
•Nutritional status
•Immune status
•Health status (lifestyle)
•Age etc.
•Multiple exposures/doses
•Via several exposure routes (skin, inhalation, ingestion)
•Environmental – indoor
•Environmental – outdoor
•Occupational •Low doses and/or
peaks•24 hours continuous•Or single dose at
critical times•Pre- and post-natal
doses•Lifetime and
cumulative ‘target’ organ dose•Biologically
effective dose•Often unknown
doses
•Initiating•Promoting•Retarding•Suppressin
g•CausingChanges in •Cells,
tissues,•Hormones•Organs•Functions;•‘normal’
‘distributions of bio-functions.
•Infections•Skin •Cancer•Neurotoxicit
y•Respiratory•Circulatory•Reproductiv
e•Other
adverse developmental impacts
HARM
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Possible strategies for avoiding, reducing and
compensating harmHOST GENETICS
Genetic Engineering ?
Remove ‘sensitive’Groups from Exposure ?
EXPOSURES
...
but which strategies would be most effective?
Improve Nutrition ?
Promote good health ?
Vaccinate ?
Reduce ?
Eliminate ?
Predict ?
Identify earlier ?
Stop/slowProgression to Harm ?
Cure ?
Compensate ?
Clean up ?
Learn from ‘mistakes’ ?
Warn ?
HOST STATE
EFFECTS HARM
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‘
Illustrative Multi-causality: Childhood asthma illustration
+ + =
+ + =25% 25%
e.g.
•Mites 10%
• Pets 5%
• Passivesmoking 5%
• NO 5%
• Damp5%
e.g.
• Pollen 10%
• Industrialpo on5%
• c
50%
30% indoor
20% outdoor
100%
X
e.g.
Allergic sensitivity
e.g.
Nutritional and immune status
30% indoor
e.g.
•Mites10%
•Pets 5%
•Passive smoking 5%
•NOx 5%
•Damp 5%
20% outdoor
•Pollen 10 %
•Industrialpollution 5%
•Trafficpollution 5%
Asthmacaused/Aggravated in somechildren
HOST GENETICS
HOST STATE
EXPOSURES HARM
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…’Reducing traffic pollution’ may be a very cost effective policy action on asthma; given
• Inter-linked causal chains
• Less dependence on individual behaviour change
• Cost effectiveness/distribution
• Large secondary benefits e.g. reduced traffic congestion, accidents; community fragmentation; CO2 etc. (‘multi-pollutant, multi-effects strategy)
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