The New Millennium: Values, Perceptions of Risk and the Key Roles of Science and Technology

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The New Millennium Values, Perceptions of Risk
and the Key Roles of Science and Technology

• Ionizing Radiation Science and Protection In the
  21st Century
• Gilbert S. Omenn, MD, PhD
• Executive Vice President for Medical Affairs and
  CEO, University of Michigan Health System
• National Council on Radiation Protection and
  Measurements
• April 5-6, 2000 Arlington, Virginia

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AMERICAN VALUES FOR THIS MILLENNIUM

• Sustainable development Robust economy,
• environmental protection, inter-dependent
  world
• Freedom of speech, freedom of religion,
  freedom from
• want, freedom from fear (FDR, 1941)
• Transparency of decision-making in an
  internet-
• informed or misinformed, more empowered
  populace
• High expectations and benefits and tolerance
  for risks
• from science and technology

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SOURCES OF IONIZING RADIATION EXPOSURES

• Nature background radon progeny
• Medical Diagnostic and Therapeutic Uses
• Industrial Radionuclides
• Radioactive Liquid and Solid Wastes
• Nuclear Power Plant Operations / Emissions Risk
• Decommissioning of Nuclear Reactors

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• I know no safe depository of the ultimate powers
  of society but the people themselves if we think
  them not enlightened enough to exercise their
  control with a wholesome discretion, the remedy
  is not to take it away from them, but to inform
  their discretion.
• - Thomas Jefferson

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RISK PERCEPTION

• NOT OBSERVABLE
• Unknown to those exposed
• Effect delayed
• New risk
• Risks unknown to science

• OBSERVABLE
• Known to those exposed
• Effect immediate
• Old risk
• Risks known to science

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• CONTROLLABLE
• Not dread
• Not catastrophic
• Not fatal
• Equitable
• Low risk to future generations
• Easily reduced
• Risk decreasing
• Voluntary

• UNCONTROLLABLE
• Dread
• Global catastrophic
• Consequences fatal
• Not equitable
• High risk to future generations
• Not easily reduced
• Risk increasing
• Involuntary

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FRAMEWORK FOR REGULATORY DECISION-MAKING

• Epidemiology
• Hazard Identification Lifetime rodent
  bioassays
• Short-term, in vitro tests
• Structure / activity
• Potency (dose/response)
• Risk Characterization Exposure analysis
• Variation in susceptibility
• Information
• Risk Reduction Substitution
• Regulation / Prohibition

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Objectives of Risk Assessment

• 1. Balance risks and benefits
• Drugs
• Pesticides
• 2. Set target levels of risk
• Food contaminants
• Water Pollutants
• 3. Set priorities for program activities
• Regulatory agencies
• Manufacturers
• Environmental/Consumer organizations
• 4. Estimate residual risks and extent of risk
• Reduction after steps are taken to reduce risks
  

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BIOLOGICAL END-POINTS

• Cancers
• Mutations
• Birth Defects
• Reproductive Toxicity
• Immunological Toxicity

• Neurobehavioral Toxicity
• Organ-Specific Effects
• Endocrine Modulation/Disruption
• Ecosystem Effects

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Major Toxic Chemical Laws

• EPA Air pollutants Clean Air Act
  1970, 1977, 1990
• Water Pollutants Fed
  WP Control Act 1972, 1977
• Safe Drinking Water
  Safe DW Act 1974
• Pesticides
  FIFRA 1972
• Ocean Dumping
  Marine Protection Act
• Toxic Chemicals
  TSCA 1976
• Hazardous Wastes RCRA
  1976
• Hazardous Waste Cleanup CERCLA
  (Sperfund) 1980, 1986
• CEQ Envvlt Impacts NEPA
• OSHA Workplace OSH
  Act
• FDA Foods, Drugs, Cosmetics FDC Acts
• CPSC Dangerous Consumer Products CPS Act
• DOT Transport of Haz Materials THM
  Act

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MANDATE

• Uses and limitation of risk assessment
• in decision-making
• Appropriate exposure scenarios
• Uncertainty and risk communication
• Risk management policy issues
• Consistency across agencies

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EXPOSURE

• Sources
• Pathways
• Environmental transformations
• Routes of entry
• Time course of exposures
• Concept of total exposure
• Need for translation from ambient levels to
  target tissue effective dose
• New methods for tissue burdens and dosimetry

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MIXTURES

• Test real world mixtures
• diesel exhaust
• urban smog
• actual effluents
• pesticide combinations
• workplaces
• Assume additivity of risks as default use
  mechanisms, if known
• Pay attention to radiation and microbial
  exposures/risks

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PUTTING ENVIRONMENTAL RISKS INTO CONTEXT

• Multi-Source
• Multi-Media
• Multi-Chemical / Multi-Agent
• Multi-Risk

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CONTEXT

• Multi-Source
• Multi-Media
• Multi-Agent
• Multi-Risk
• Public Health
• Status/Trends
• Ecological Health
• Social Cultural
• Environmental Justice Considerations

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Reducing risk by orders of magnitude is not
equivalent to linear reductions
Risk Commission, Final Report, 1997
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RISK COMMISSION RECOMMENDATION (1997 REPORT, p.
82)

• A concerted effort should be made to evaluate and
  relate the methods, assumptions, mechanisms, and
  standards for radiation risks to those for
  chemicals to clarify and enhance the
  comparability of risk management decisions,
  especially when both types of hazards are present.

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• LACK OF COLLABORATION ON CHEMICAL AND RADIATION
• HAZARDS
• Different models of carcinogenesis
• Different regulatory laws and agencies
• Different disciplines and scientific meetings
• Smaller margin of exposure tolerated for IR
• Despite common waste streams and co-existing
  contamination

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POLICY AND PUBLIC INTEREST IN COMPARISONS OF RISK

• Discrepancy between levels of risk considered
  negligible for
• radiation exposures and for chemical exposures
• Workers General
  Population Comments
• Chemicals 10-3 10-6
  Single chemicals
• Radiation 50 mSV/yr 1mSV/yr
  Integrated
• Dose
• 10-1 / 10-2 Ratio of 50
• 
  vs 300
• Importance of interactions of radiation and
  chemicals, of
• radiation and infectious disease risks.

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BEIR VII - Phase 1 Letter---21 January, 1998

• Continued reliance on epidemiological studies
• Lots of laboratory studies
• OPPORTUNITY FOR REALLY BIG BREAKTHROUGH
• - Patterns of gene expression on microarray
• and protein expression in proteomics
• readouts that reflect carcinogenesis key
  to
• resolving long-festering questions about
  risks of
• low-level exposures

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OUR GENETIC FUTURE

• Mapping the human genetic terrain may rank with
  the great expeditions of Lewis and Clark, Sir
  Edmund Hillary, and the Apollo Program.
• --Francis Collins, Director
• National Human Genome Research Institute, 1999