Risk and Ethics: Societal Benefits Vs' Societal Risks

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Risk and Ethics Societal Benefits Vs. Societal
Risks

• Engineering 124
• W. E. Kastenberg

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Historical Perspective
...the appearance of disease in human
populations is influenced by the quality of air,
water, and food the topography of the land and
general living habits.

the ancient-Greek physician Hippocrates in his
treatise Air, Water and Places


We Athenians in our persons, take our decisions
on policy and submit them to proper discussion.
The worst thing is to rush into action before
the consequences have been properly debated. We
are capable at the same time of taking risks and
estimating them before hand. Others are brave
out of ignorance But the man who can most truly
be accounted brave is he who best knows the
meaning of what is sweet in life, and what is
terrible, and he then goes out undeterred to
meet what is to come.

From Pericles Funeral Oration in Thucydides
History of the Peloponnesian War (started in
431 BC)
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What Is Risk?
Risk 1. Possibility of loss or injury.
2. A dangerous element or factor. 3.
The chance of loss. 4. A person or
thing that is a specified hazard.


Safe 1. Free from harm or risk. 2.
Secure from treat of danger, harm
or loss. 3. Affording safety from
danger.
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Risk Analysis

• What are the risks imposed by human activities
  and natural phenomena? (Risk assessment)
• Are these risks acceptable? (Risk valuation)
• Can these risks be reduced? (Option generation)
• How can the options be evaluated? (Cost/benefit)

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Risk Assessment

• Risk assessment asks three questions
• What can go wrong ?
• How likely is it to happen?
• What are the consequences?

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Quantifying the Risk of Accidents

• Risk - the expected value of an undesirable
  consequence.
• i ith sequence
• fi frequency of occurrence
• xi consequence of undesirable
  event

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Risk (Sequences and Consequences)
Consequence
Exposure
Event
Acute Effects
Acute
Latent Effects
Accidental Release
Latent Effects
Chronic
Chronic Release
Chronic
Latent Effects
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Examples of Risk Measures

• Consequence or Hazard Measure of Risk
• Acute Fatalities Early Deaths/ Year
• Cancer Death Latent Deaths/ Year
• Contaminated Land Acres Lost/ Year
• Contaminated Water Concentration in Drinking
  Water or Wells Closed/ Year
• Economic Loss Lost/ Year
• Genetic Effects Mutations/ Year
• Teratogenic Effects Birth Defects/ Year
• Neurological Disease Illness/ Year
• Species Loss Species Loss/ Year
• Core Melt Events/ Year

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How Does Risk Assessment Work?

• What are the risks from driving an automobile?
• There are 15,000,000 accidents per year, 1 in 300
  of which result in death, there are 250,000,000
  people

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Fault and Event Trees
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Risk From Toxic Chemicals

• Risk is a function of exposure toxicity
• How much of the toxic material is the individual
  going to be exposed to?
• What amount of toxic material is likely to cause
  an adverse health effect?
• Location and strength of source (Qij)
• Model the spread of the plume (Xi)
• Model the exposure to human or other species
  (Eij)
• Model the dose response relationship (DRi)

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Risk Assessment

• Hazard identification uses toxicology (cell,
  tissue and animal tests) and epidemiology
  (population data and field samples)
• Exposure assessment includes determination of
  sources, environmental concentrations, exposure,
  dose, and uncertainties

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Framework for Risk Assessment
Transport and transformation
Source/ Inventory

Emission
Exposure Events
Risk Mitigation
Dose/Response
Biokinetics
Uptake
Risk Characterization
Response
Dose
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A Multimedia, Multiple Pathway Exposure Model
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Environmental Fate and Transport
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Inter-media Transfers

• Air and soil to food

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Multiple Exposure Pathways
Inhalation
Activity Patterns
Dermal
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Mechanism of Action

• Whether a compound reaches a target tissue
  depends on
• Absorption through the GI tract, lung, or skin
• Distribution in the body
• Biotransformation
• Excretion

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Ethical Basis for Risk Management

• Ethics based on a universal set of rules and
  principles after Descartes (1596-1650)
• John Locke (1632-1704) Rights Ethics.
• Immanuel Kant (1724-1804) Duty Ethics.
• Jeremy Bentham (1748-1832) and John Stuart Mill
  (1806-1873) Utilitarianism.

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Utilitarianism

• Engineering and technological decision making,
  for the most part, are based on derivatives of
  utilitarianism.
• A basic tenant of utilitarianism is the greatest
  good for the greatest number.
• This gives rise to economic determinism as
  manifest in cost/benefit and risk/benefit
  analyses.

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Drawbacks of Utilitarianism

• Only the total good, and not its distribution
  among people, is relevant to moral choice.
• Difficulty in attempting to quantify the greatest
  good.
• Utilitarianism tends to be anthropocentric.
• Utilitarianism judges by consequences rather than
  actions.

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Cost/Benefit and Risk/Benefit

• Insurance how much am I willing to spend each
  year to insure my house, car, life and for what
  amount?
• Energy what risks am I willing to take for the
  benefit of 1,000 MWe among a coal, natural gas,
  oil or nuclear power plant?
• Medical how many lives can I save by inoculating
  all children against polio (or having all women
  over the age of 40 have a yearly mammogram) and
  at what cost and risk?

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Societal Values and Acceptable Risk

• Quantitative safety goals for nuclear power
  plants (0.1 of background acute and latent
  fatality risk).
• Hazardous facilities on the order of 10-6 per
  year.
• ALARA (for example 1000/person-rem averted).
• Remediation of contaminated sites (acceptable
  excess lifetime cancer risk).

10-4
10-6
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Qualitative Safety Goals

• Individuals should bear no significant additional
  risk to life and health to that from which they
  are ordinarily exposed.
• Societal risks to life and health from nuclear
  power plant operation should be comparable to or
  less than the risks due to electric generation by
  competing technologies and should not be a
  significant addition to other societal risks.

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Quantitative Safety Goals

• Risk to the average individual in the vicinity of
  a nuclear power plant of prompt fatalities that
  might result from reactor accidents should not
  exceed one-tenth of one percent (0.1 percent) of
  the sum of prompt fatality risks resulting from
  other accidents to which members of the US
  population are generally exposed.
• The risk to the population in the area near a
  nuclear power plant of cancer fatalities that
  might result from nuclear power plant operation
  should not exceed one-tenth of one percent (0.1
  percent) of the sum of cancer fatality risks
  resulting from all other causes.