Presentation to the Western Occupational Safety &
Health Group of ORC – 16 June 2009, Irvine, CA.
Mike Cooper, Senior Managing Scientist, Exponent Inc.
mcooper@exponent.com
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Good Science – Process of formal reasoning
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Clear, well defined methodology
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Allows independent testing & verification
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Replicable data and defined analysis
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Open debate, healthy skepticism, respect
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Veracity in methodology, data collection, and reporting - ethical
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Conclusions drawn from data instead of foregone
Junk Science aka Novel Science – Unproven or questionable
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Term used in US political and legal disputes that labels questionable scientific data, research, or analyses as spurious or worse…
• The term Junk Science was used prior to 1985 when it was referenced in by a US Dept. of Justice Tort policy working group as meaning “invalid scientific evidence” which resulted in findings of causation which can not be justified
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1962 Silent Spring, R. Carson
1985 Outrageous Misconduct – The Asbestos Industry on Trial, P. Brodeur
1991 Galileo’s Revenge – Junk Science in the Courtroom, P. Huber
1993 Huber’s Junk Scholarship, K. Chesebro
1998 Dancing Naked in the Minefield, K. Mullis
2000 The Expert Witness Scam, L. Robertson (reprinted 2006)
2002 Deceit & Denial, The Deadly Politics of Industrial Pollution, G. Markowitz, G. D. Rosner
2003 Bushwacked, Life in GW Bush’s America, M. Nina, L. Dubose
Science in the Private Interest; Has the Lure of Profits Corrupted Biomedical Research?, S. Krimsky
2008 Poisoned Profits- the Toxic Assault on our Children, P. &A., Shabecoff
Doubt is their Product- How Industry’s Assault on Science Threatens Your Health, D. Michaels
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Agnotology
“ the study of culturally induced ignorance or doubt, particularly the publication of inaccurate or misleading scientific data”
Wikipedic definition- coined in the early part of the decade by Stanford professor R. Proctor citing the highly publicized data from the tobacco industry
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• Public trust in science & scientists is under scrutiny
Funding & other disclosure issues
Private research (industry, trade associations) submitted to regulators
Rules differ for Federal funded; data, CBI, Data Quality Act, no conflict
Bias is assumed – everyone has a dog in the fight
• Polarization
Public apathy or public involvement
Increased call for regulations
• Causation/product legal issues
Antidotal claims increase
Causal and conspiracy theories abound
Sometimes… good science can get lost in the mix…
• Cost
Regulatory delay & belief that the public is hurt as a result
Companies have been hurt (cost/time/brand)
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• Science theories and methods are used to establish legal causation and establish liability
• The stakes are high: competition, profits, funding, careers, ego, etc.
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The practice of science remains a human endeavour
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David Hume – “ proof is impossible in empirical science ”
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Hill Criteria or Viewpoints (1965) built on the1964 Surgeon
General’s Report
Strength
Consistency
Specificity
Temporality
Biological gradient
Plausibility
Coherence
Experimental Evidence
Analogy
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Federal Judiciary Committee (2000)- Reference Manual on
Scientific Evidence
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Association
Causation judgments
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Reference Manual on Scientific Evidence
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Can not be inferred by data analysis alone
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One must infer that causality exists on the basis of an underlying causal theory that explains the relationship between the two variables
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Even with an appropriate theory is established, causality can never be inferred directly
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One must also look for empirical evidence that there is a causal relationship
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The absence of a correlation does not guarantee that a casual relationship does not exist- lack of correlation can exist if
Insufficient data
Data are measured inaccurately
Data do not allow multiple causal events to be sorted out
Model is wrong; omission of variables or variables
Two variables that are correlated does not guarantee that there is a relationship…
It could be that the model does not reflect the correct interplay of the variables
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There is a tension between any attempt to reach conclusions with near certainty…
…and… the inherently probabilistically nature of multiple regression analysis.
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Third North Sea Conference 1990
“The participants…will continue to apply the precautionary principle, that is to take action to avoid potentially damaging impacts of substances that are persistent, toxic, and liable to bioaccumulate even when there is no scientific evidence to prove a causal link between emissions and effects”
Treaty on European Union 1992
“Community policy on the environment…shall be based on the precautionary principle and on the principles that preventative actions should be taken, that the environmental damage should as a priority be rectified at source and that the polluter should pay”
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prevention of serious & irreversible effects
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persistent, toxic and liable to bioaccumulate
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lack of full scientific certainty shall not be used as a reason to postpone action
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cost-effective measures
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difference between knowing about a hazard and the likely causes – and understanding the underlying scientific processes
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use of minority scientific opinion in setting public policy making
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latent lag-times between exposure and health effects
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zero exposure and risk is the only acceptable solution
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yes/no gate
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Two example categories
• Basic science is performed to determine causation, investigate issues, test theories, expand scientific knowledge, come up with better ideas to prevent failures
• Determine conclusions from the body of scientific literature
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Background
• Piper Alpha Oil platform in the North Sea cost
$1B to build; produced 250k barrels and 100M ft3 gas per day
• 1988 fire and explosion- 167 killed, $2-3B paid in insurance claim, 25% British oil production lost for 1y, greatest single insurance loss caused by man
• Alleged cause of accident scientifically investigated
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• Cause found to be a leaking gas valve + spark
• Investigation showed chain of events in accident
Water suppression turned off
Crew working on generator over shift change
Lifeboats did not inflate
Crew quarters above process level contributed to deaths
Difficulty getting to helo pad
• Society Changes
Science altered the way platforms were built
Changed location of crew quarters & access
Redundant systems
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Background
• Potential public health issue - 33% women over 18 and
10% of men over 40 are estimated to use hair dyes
• Paraphenylenediammine is an arylamine used extensively in permanent hair dyes
• Exposure to certain arylamines has been associated with bladder cancer based on hydroxylated metabolites
& possible genotoxic potential
• IARC 1997 suggested that there is inadequate epidemiologic evidence that the personal use of hair dye entails exposures that are carcinogenic
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Body of Literature
Huncharek &
Kupelnick
2005 – Public
Health Reports
Takkouche et.al.
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JAMA
Suggested that an association exists between personal hair dye use and bladder cancer ?
Suggested that NO association exists between personal hair dye use and bladder cancer
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• Protect good science & the right of industry to fund/perform good science & research.
• Disclose funding sources and move on… debate the science.
• Support open and transparent public debate.
• Merge good science with feasibility/cost.
• Identify and quantify uncertainties.
• Minimize ad hominum arguments.
• Admit & learn from errors.
• EU enforcement of the precautionary principle and further adoption by the US Regulatory community
• Use of the evidence based decision making – e.g. the Cochrane Approach
• Revision of history in the liability debate
• Comprehensive product chemical & life cycle analysis – Biomonitoring, Green Chemistry
Initiative
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Background
• During a CPSC review and following a lawsuit and appeal of a fatality case, NBC alleges safety defects in GM C/K trucks in 1992
• Video made of a 30 mph test crash by the independent Institute for Auto Safety was used in a NBC Dateline program. Video shows crash results in a fire – questions raised
• An investigation followed…
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Tanks were x-rayed and it determined that they had not ruptured
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Gas cap found to be generic
Gas was reportedly filled to the neck of the tank
Similar crash tests at 30mph had been performed without compromising the truck fuel tanks
Crash speed determined to be closer to 40mph
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Video footage analysed frameby-frame showed smoke originating from the truck undercarriage
Remnants of wiring and a burnt rocket motor (incendiary device) were found in the cab
Conclusion : During the crash gasoline spilled from the full tank and was externally ignited.
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• GM filed defamation suit
• NBC retracted the conclusions and issued an apology
NBC director and reporter fired, independent auto safety firm not in business anymore
• Lawsuit was settled by GM
• Society Changes
Tragic event & loss - someone should pay
Debate enters legal & regulatory arena for causation
Media “scientific demonstration” is made public
Defense needs a scientific inquiry
Bad science is exposed, reparations are made
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