Risk and Ethics: Social Benefits Vs. Societal Risks

1
Risk and Ethics Social Benefits Vs. Societal
Risks

• Engineering 124
• March 18 20
• W.E. Kastenberg

2
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)
3
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. Freed from harm or risk. 2.
Secure from treat of danger, harm
or loss. 3. Affording safety from
danger.
4
Risk Analysis

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

5
Risk Assessment

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

6
Risk (Sequences and Consequences)
Consequence
Exposure
Event
Acute Effects
Acute
Latent Effects
Accidental Release
Latent Effects
Chronic
Chronic Release
Chronic
Latent Effects
7
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

8
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

9
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

10
Fault and Event Trees
11
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)

12
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

13
Framework for Risk Assessment
Transport and transformation
Source/ Inventory

Emission
Exposure Events
Risk Mitigation
Dose/Response
Biokinetics
Uptake
Risk Characterization
Response
Dose
14
A Multimedia, Multiple Pathway Exposure Model
15
Environmental Fate and Transport
16
Inter-media Transfers

• Air and soil to food

17
Multiple Exposure Pathways
Inhalation
Activity Patterns
Dermal
18
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

19
From Animal Experiments to Human Risk Factors

• Advantages
• Carefully controlled conditions
• Mostly closed systems
• Limitations
• High doses required
• Extrapolation to humans
• Important conditions
• Concentration or dose
• Time to tumor measured
• Maximum tolerated dose
• What do we get from these experiments?
• No effects
• Threshold of effect
• Dose-response models

20
Dose Response Models

• Dose-response models can be classified according
  to how they represent risk at low doses
• R(d) const x dm
• m 1 is linear
• mgt1 is sublinear
• mlt1 is supralinear

21
Low-Dose Models

• Statistical models--tolerance distribution models
• Probit (sub-linear) - a lognormal tolerance model
• P(d) a b log(d)
• Logit (sub-linear) - characterizes tolerance
  distribution with a logistic function
• P(d) 1/ (1 exp(-a b log(d) )
• Weibull - Time to tumor distribution
• P(d) 1 - exp(-a - bdm)

22
Low Dose Models

• Stochastic or hit models
• One-hit model - Derived from Poisson statistics
• P(d) 1 - exp(-a - b d)
• Multi-stage- Based on the stage theory of cancer
  as first proposed by Armitage and Doll
• P(d) 1 - exp(-a - b1 d - b2 d2 - b3 d3
  ...)
• Linearized Multi-stage model--the b1 parameter is
  replaced by its upper confidence limit.
• Biologically-based cancer models

23
Hazard Quotient Models

• Used primarily for non-cancer health endpoints
• Define safe dose
• ADI allowable daily intake, mg/day
• RfD Reference dose, mg/kg/d
• Risk is based on a hazard index HI Dose/ADI
• Often calculate RfD based on animal studies

24
Benchmark Dose

• RfD NOAEL / (UFs x MFs)
• UF uncertainty factor MF modifying factor
• NOAEL no observed adverse effects level
• LOAEL lowest observed adverse effects level
• Modifying factors include
• Interspecies adjustment,
• Subchronic to chronic,
• LOAEL to NOAEL

25
EPA Hazard Identification

• Physical-chemical properties and routes and
  patterns of exposure
• Structure -activity relationships
• Metabolic and pharmacokinetic properties
• Toxicological effects
• Short-term tests - in vitro and in vivo
• Long-term animal studies
• Human studies
• Weight of evidence

26
EPA Weight of Evidence

• Group A - Human carcinogen based on sufficient
  human evidence
• Group B1 - Probable human carcinogen based on
  limited human evidence and sufficient animal
  evidence
• Group 2B - Probable human carcinogen base on
  insufficient or no human evidence and sufficient
  animal evidence
• group C - Possible human carcinogen based animal
  evidence
• Group D - Not classifiable
• Group E - Evidence of non-carcinogenicity for
  humans

27
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.

28
Qualitative Safety Goals

• Individuals bear no significant additional risk
  to life and health
• 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

29
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

30
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.

31
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?

32
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.

33
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
34
Risk Analysis Has Become an Important Tool in

• Remediation of Superfund sites.
• Assessing space missions.
• Improving safety at chemical process plants.
• Improving safety at plants that generate
  electricity (fossil fueled and nuclear).
• Setting insurance rates.

35
Our Basic Premise

• Risk analysis my be limited in its accuracy and
  completeness when attempting to evaluate and
  manage the risks of emerging technologies.

36
Emerging Technologies

• Biotechnology
• Information technology
• Nuclear technology
• Energy technology global climate change
• Nano-technology

37
Limiting Assumptions of Risk Analysis

• A focus on the factuala quantification of the
  undesirable consequences of technology such as
  human health effects and environmental
  degradation.
• Does not focus on the axiologicalthe evaluation
  of the unintended impacts of technology on the
  manner in which we live psychologically,
  socially and spiritually.

38
Limiting Assumptions of Risk Analysis

• The paradigm or context that defines the culture
  of risk analysis is linear and dualistic.
• The quantification of risk is based on
  reductionism which leads to an objective search
  for causal links or causal chains.
• The management of risk is based on a set of
  universal rules (quantitative safety goals) or
  principles (cost/benefit analysis).

39
The Newtonian-Cartesian Paradigm

• Atomistic leads to reductionism or
  fragmentation.
• Deterministic leading to cause and effect.
• Subject/object dualism observation does not
  affect the system being observe The laws
  governing a systems behavior can be deduced from
  objective empirical observations (objectivism).

40
Insufficiency of the Risk Paradigm

• The interplay between technology, society and the
  environment has always been nonlinear.
• In the past, however, the consequences of
  technology were geographically local and/or they
  were observable in real time.
• This gave the impression that a linear paradigm
  was an accurate worldview.

41
Insufficiency of the Risk Paradigm

• Modern technologies can have global impacts
  (ubiquitous) that may be irreversible and/or can
  be imperceptible with time.
• Hence their consequences have large spatial
  domains and/or either very short or very long
  temporal scales so that nonlinear effects become
  dominant.

42
Complex or Nonlinear Systems

• Holism the whole system cannot be described by a
  knowledge of its parts alone.
• Chaotic small changes in input can lead to large
  changes in output and/or there may be many
  possible outputs for a given input.
• Subjectivism some aspects of the system may not
  be describable by objective means.

43
Uncertainty

• Aleatory uncertainty in data.
• Epistemic uncertainty in models.
• Indeterminacy many possible outcomes for a given
  input.
• Ignorance we dont know what we dont know.

44
Ambiguity

• Ambiguity refers to the variability of
  (legitimate) interpretation based on identical
  observation or data assessments.
• Differences in interpreting factual statements
  about the world.
• Differences in applying normative rules to
  evaluate the state of the world.

45
What Is a System?

• A set of objects (parts, objects, components or
  subsystems).
• The attributes of the objects (mass, volume,
  temperature, charge, etc.).
• A set of relationships between the parts and a
  set of relationships between the attributes.
• (The set of objects defines a boundary around the
  system which may be physical or conceptual.).

46
General Systems Theory

• The system is not only a whole, but also a part
  within a larger whole.
• The system has permeable boundaries.
• The system is self organizing.
• The system behavior is stochastic or chaotic and
  may achieve equilibrium through a trial and
  error process.

47
Emergent Property or Quality

• When we say, the whole is greater than the sum
  of its parts, we mean that there is an emergent
  property or quality that the whole possesses that
  is not found in the parts.
• For example, when hydrogen and oxygen come
  together to form water, we have the property of
  wetness.

48
Self-similarity
49
Shape Preserving Bisections
A1A0/2
A0
A1A0/2
...
Ai A0/2i
A2A0/4
A2A0/4
50
Community-level Self-similarity
Prob(?) a
Ai Ai-1/2
? is randomly chosen from , , ,
,
Ai-1
51
Serpentine Flora Species-Area Relationship
z 0.21 r2 gt 0.999 a -log2(z) 0.86
52
Elements of a Research Agenda

• Characterizing risk should be a decision driven
  activity, directed at informing choices and
  solving problems.
• Managing risk requires a broad understanding of
  the relevant consequences and impacts.
• Risk characterization is the outcome of an
  analytic-deliberative process.

53
Decision-driven Activity

• Do our emerging technologies create axiological
  resonance or dissonance within the society within
  which they are to be implemented?
• In order to answer this question, we require
  research aimed at expanding the decision making
  activity from a set of universal rules and
  principles to one that is also contextual or
  situational based.

54
Broad Understanding of Risk

• Research to expand the paradigm of risk
  characterization from reductionism to holism.
• Consideration of both the undesirable (factual)
  consequences and the unintended (axiological)
  impacts.
• Discovery of emergent properties or qualities of
  complex systems.
• Inclusion of qualitative as well as quantitative
  consequences and impacts.

55
Analytic-deliberative Process

• Epistemological dialogueexperts consider factual
  assessment.
• Reflective dialoguepolicy makers, scientists and
  stake-holders consider risk management.
• Participatory dialogueinclusion of public
  citizens and focused on societal values and
  ethical considerations.
• Dialogueallowing the emergence of possibilities
  that were unthinkable prior to the dialogue.