Risk Assessment

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    Risk Assessment

    Yes, I do want you to do the readings
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       What are the basic concepts applicable to all environmental
        risk assessments
           - human health risk assessments
           - ecological risk assessment
           - industrial applications of risk assessments
+                                                      4




       What are the unifying concepts?

       What are their currently used methodologies?

       How are they applied?
+                              5

    Risk assessment concepts

       Hazard

       Risk

       Risk assessment

       Risk management

       Risk perception

       Risk communication
+ The technique of risk assessment is used in a wide range of        6


    professions and academic subjects

   Risk assessment has become a commonly used approach in
     examining environmental problems.

   For instance, the approach is used to assess the environmental
    risks posed by Genetically Modified Organisms (GMOs),
    chemicals, ionising radiation and specific industrial plants.

   Definitions in risk assessment are all-important because of the
    wide range of uses of the approach, and different meanings
    of terms used by different groups of experts and
    practitioners.
+
Hazard

                                                                                      7


       “the potential to cause harm”
       Can be defined as “a property or situation that in particular could lead to
        harm”

   Risk
       A more difficult concept to define
       Used to mean “chance of disaster”
       In the process of risk assessment, most commonly means: ‘the combination
        of the probability, or frequency, of occurrence of a defined hazard and the
        magnitude of the consequences of the occurrence.”
       Risk = Severity x Likelihood

   Risk assessment
       the evaluation of the degree of harm or danger from some condition such
        as exposure to a toxic chemical - either quantitatively or quanlitatively
       The process of determining an expected annual mortality
       Carried out to examine the effects of an agent on:
           Humans (health risk assessment)
           Ecosystems (ecological risk assessment)
+                                                                                  8

    Environmental risk assessment
    (ERA)
       examination of risks resulting from technology that threaten
        ecosystems, animals and people.

       Includes
           human health risk assessments,
           ecological or
           ecotoxicological risk assessments,
           and specific industrial applications of risk assessment that examine
            end-points in people, biota or ecosystems.

           Many organisations are now actively involved in ERA, developing
            methodologies and techniques to improve this environmental
            management tool.
             OECD (organization for economic cooperation and development)
             WHO (world health organization)


            One of the major is the availability and certainty of data
+ perception
Risk
                                                                                    9

       What do the risks mean to those effected?
         Depends on how the risk is perceived
         depend heavily on how the risk is perceived. Risk perception involves
          people's beliefs, attitudes, judgements and feelings, as well as the
          wider social or cultural values that people adopt towards hazards and
          their benefits.
         Risk perception will be a major determinant in whether a risk is
          deemed to be "acceptable" and whether the risk management
          measures imposed are seen to resolve the problem.

   Risk Management
       the decision-making process through which choices can be made
        between a range of options which achieve the "required outcome” – i.e.
        reduction of risks to an "acceptable" level within the constraints of the
        available resources.
       Managed how?
         Eliminated (total ban on the use or marketing of a hazardous chemical)
          (but what about the substitute?)
         Transferred (risk transferred to insurance companies, eg)
         Retained (more often retained w/o knowledge)
         Reduced (most common approach; regulation, voluntary industry
          agreements
+ As Lois Gills of Love Canal stated                   10




  ‘From a community’s perspective, risk
   assessments are ‘the risks that someone else
   has chosen for you to take.’ What is a life worth
   … but equally important is whose life”’


   Is risk a technical matter that is determined
   objectively or a social construction that
   emerges from communication among experts,
   affected parties, and public agencies?
+  Risk communication                                                    11


       Simplest form: any public or private communication that informs
        individuals about the existence, nature, form, severity, or
        acceptability of risks
       An increasingly important area of risk management
       The way in which information relating to risks is communicated
       Closely linked to risk perception


    Can be:
        one-way transmission of information
        two-way exchange of views on the risk
+                                                                                12

    Role of risk assessment in
    environmental management
       Can be used in the design of regulation
           Targets for regulation can be selected (risks > benefits?)
           Societally ‘acceptable’ risk levels can be determined (ALARP)
           Decisions can be made on the appropriate level of risk reduction

       Can provide a basis for site-specific decisions, for instance in land-
        use planning or siting of hazardous installations (eg: risk posed by
        contaminated land sites in relation to the land’s proposed use and
        remediation measures)

       To prioritize environmental risks, for instance in the determination
        of which chemicals to regulate first – within context

       To compare risks; for instance to enable comparisons to be made
        between the resources being allocated to the control of different
        types of risk, or to allow risk substitution decisions to be made.
  What risk assessment and management can and
+ cannot do                                                                         13


   Good points
        A technique which can weigh-up information that is basically in
        different "languages” (provides a bridge between the scientific and
        the social)
        A mechanism to aid decision-making (aid)
       As a means of comparison between risks to determine whether
        there is equity of action or that the action is proportionate to the risk
         A basis for effective risk communication (but there are limitations –
        need to address the value issues that underlie the perception of
        risk)
        A method for highlighting and prioritising research needs

   Pitfalls
        Possible over-reliance and over confidence in results
        (uncertainties)
       Narrow focus on parts of a problem rather than the whole (parts, not
        the whole)
       Awkward relationship between risk assessment and the
        precautionary principle
+                                                                    14

    A typology of risk assessment and
    management methods

       Human health risk assessment

       Ecological risk assessment

     The former have a differing historical development and
     regulatory and policy imperatives

       Applied industrial risk assessment (more engineering risk
        assessment)

       Methodology least developed for ecological risk assessment
+   15
+                                                                      16

Overview of risk assessment methods

   What are the steps required in all types of risk assessment?

   Number of hazards that can be examined through ERA is vast

   Techniques have also evolved differently due to the
    institutional basis of the risk assessor and the intended use of
    the risk assessment
+                                                                    17

    Nat’l Academy of Sciences model

    1.   Hazard Identification

    2.   Dose-Response Assessment

    3.   Exposure Assessment

    4.   Risk Characterisation



    -    Developed for human health risk assessment; formed the
         basis of ecological models of risk assessment used in the
         US

    -    But does not encompass all the types of ERA in use
+                                 18

    ERA unifying steps

    1.   Problem Formulation:

    2.   Hazard Identification

    3.   Release Assessment

    4.   Exposure Assessment

    5.   Consequence Assessment

    6.   Risk Estimation

    7.   Risk Evaluation
+   19
+                                                         20

    Health Risk Assessment

       Methodologies and techniques firmly established

       Physical Risks - Ionising Radiation

        Chemical Risks

        Food Safety Risk Assessment
+                                                                                21

    Chemical Risk Assessment

       Legislation
           The procedures, methods and techniques for regulatory risk
            assessment of chemicals in the EU is described in both legislation
            and supporting Technical Guidance Documents. Implementation
            is supported by the European Chemicals Bureau, part of the Joint
            Research Centre, in Ispra.
           Same with the US.
           What about Lebanon?
           International Organisations such as OECD, IPCS and ECETOC and
            many National Organisations are conducting programmes on
            human health and ecological risk assessment. The work
            contributes both to the shaping of regulation and the response to
            regulation.
+                                                                        22

    CRA

       Human Health Risk Assessment for Chemicals

       Based on the NAS model. Remember that?

       Difference in methodology is due to difference in class of
        chemical and toxicological end-point being assessed

       All human health risk assessments of chemicals include
        hazard identification, dose-response assessment, exposure
        assessment and risk estimation/characterisation.

       Hazard Identification is defined as "the identification of the
        adverse effects which a substance has an inherent capacity to
        cause" (CEC, 1993). This involves consultation of any
        toxicological and epidemiological data.
+                                                                             23

    CRA: Human Health Risk –
    chemical risk
       Dose-Response Assessment
           Dose-response assessment is the "estimation of the relationship
            between dose, or level of exposure to a substance, and the
            incidence and severity of an effect" (CEC, 1993).
            The dose-response relationship is gotten from epidemiological
            and toxicological data
           The principle of the assessment is to compare the [ ] of a
            substance to which a pop is exposed w/ the [ ] of a at which no
            adverse effects are expected to occur

       Risk reduction measures
           Raising awareness on the safe handling of substance
           Use of emission permits with set limits
           Marketing restrictions
           Total ban of a substance or activity
+                                                                                24

    CRA: Human Health Risk
    Assessment for Chemicals
       Exposure Assessment
           Typically based on the NAS model
           The "determination of the emissions, pathways and rates of
            movement of a substance and its transformation and degradation
            in order to estimate the concentration/doses to which human
            populations or environmental compartments are or may be
            exposed”
           Environmental exposure to chemicals can be direct - as a result of
            emission to the environment (air, land, water) of a substance
            through industrial manufacture, use or disposal,
           or indirect - through drinking water or the food chain.
+ Reminder: NAS model                                                                          25

   Hazard Identification
       Objective is to identify the substance(s) that could injure humans exposed to them
        and thus to reduce injury
       A relation exists between the dose of agent received and the response produced.
        Experiments conducted. Use of epidemiological data (mainly based on
        observational approaches)

   Dose-response assessment
       Estimation of the relationship between dose, or level of exposure to a substance,
        and the incidence and severity of an effect. Typically –direct human data is
        lacking

   Exposure assessment
       Determination of the emissions, pathways and rates of movement of a substance
        and its transformation and degradation to estimate the [ ] / doses to which human
        populations or environmental compartments are or may be exposed
       Via lungs, via digestive tract, and via skin
       A range of exposure values should be estimated

   Risk characterisation
       Estimation of the incidence and severity of the adverse effects likely to occur in a
        human population or environmental compartment due to actual or predicted
        exposure to a substance; may include ‘risk estimation’ (quantification of
        likelihood); summary of data in risk assessment process + uncertainties
+   26
+                27

    Start here
+                                                           28

    Different typologies of health risk
    assessment
       * Neurotoxic (examples of lead and pesticides)

        * Immunotoxic (example of allergenic substances)

        * Developmental (example of thalidomide)

        * Reproductive (example of phthalates)

        * Carcinogenic (example of dioxins)
+                                                                            29

    HRA – biological risks

       those risks associated with biological agents of concern to
        public health such as pathogenic strains of bacteria, which are of
        particular concern as food-borne hazards,

       and those risks associated with the introduction of genetically
        engineered organisms into the environment or the food chain.

       The World Health Organization has adopted risk assessment as
        the main way to scientifically justify food safety standards
        (FAO/WHO, 1995).

        However, significant problems exist when applying quantitative
        risk assessment techniques to microbial hazards, such as the
        difficulties in obtaining dose-response data and elaborating
        appropriate dose-response relationships in humans
+                                                      30

    Ecological risk
    assessment
       Ecological Risk Assessment (EcoRA)
        involves the assessment of the risks
        posed by the presence of substances
        released to the environment by man, in
        theory, on all living organisms in the
        variety of ecosystems which make up
        the environment.

       EcoRAs tend to focus:
           risks from chemicals and Genetically
            Modified Organisms (GMOs)
           physical risks such as temperature rises
            caused by cooling water releases from
            industry.
+                                                                            31

    Ecological Risk Assessment
       EcoRA methodology has been developed from that already
        established for human health.

       The general principles are widely agreed upon but the
        application of the process still provokes considerable
        argument.

       The Health Risk Assessment (HRA) approach lends itself well
        in many respects to EcoRA but, due to the complex nature of
        the potential target(s) or receptor(s), several problems have
        presented themselves to practitioners.
           HRA is concerned with individuals and morbidity and mortality,
           EcoRA -- populations and communities and the effects of
            substances on mortality and fecundity.
           Thus…
+                                                                                    32

    EcoRA
       EcoRA has to deal with a multitude of organisms, all with varying
        sensitivities to chemicals and various groups have distinct
        exposure scenarios

       Because of the difficulty in obtaining toxicity data on all
        organisms in an ecosystem,
            the recognised practice is to test selected representatives of major
            taxonomic groups and use these as surrogates for the whole system.

       But: This method is questionable

       It may not protect the most sensitive species exposed in the
        environment.

       Failure to identify the effects of an agent on a potential receptor
        can result in widespread damage to organisms and ecosystems.
+                                                                                           33

    The Risk Assessment Process for
    Chemicals
       The method for ERA as used by the EU

       Four steps used in Health Risk Assessment

       Effects Assessment involves the identification of the hazard based on its
        physico-chemical properties, ecotoxicity and intended use, and the
        estimation of a Predicted No Effect Concentration (PNEC), derived from
        ecotoxicity data and the application of assessment factors;

       Exposure Assessment involves the calculation of a Predicted Environmental
        Concentration (PEC). This is derived using monitoring data, realistic worst
        cases scenarios and predictive modelling techniques. It is a complex task
        and should consider release, degradation, and transport and fate
        mechanisms. Local relevant emission and distribution routes are shown in
        Figure 6.3.

        Risk Characterisation involves the calculation of a quotient - the PEC/PNEC
        ratio. If the ratio is less than 1 the substance is considered to present no risk
        to the environment in a given scenario.
+ Exposure assessment: Local relevant   34


  emission and distribution routes
+                                                                      35

    ERA
    a   developing field
     Many    problems which need resolving such as;
        Determining the effects at population and community
         levels
        Selection of end-points;
        Selection of indicative species;
        The selection of field, laboratory, mesocosm and
         microcosm tests
        The incorporation of resilience and recovery factors of the
         ecosystem.

        Many organisations are actively involved in the
         development of ecological risk assessment methodology,
         they include the US EPA, the US NRC, OECD, SETAC and
         ECETOC.
+                                                                         36

    Evaluation of risk and risk
    management
       Complex process of determining the significance or value of the
        identified hazards and estimated risks to those concerned, or
        affected

       The evaluation of risk is concerned with issues relating to how
        those affected by risks perceive them, the value issues
        underlying the perceived problem and the trade-off between
        the perceived risks and benefits.

       Let’s look at the factors involved in risk perception and risk
        acceptance.

       We will also examine the advantages and disadvantages of the
        major approaches used in making risk management decisions -
        bootstrapping, formalised methods such as cost-risk-benefit
        analysis, and professional judgement.
+                                                                       37

    The importance of risk evaluation
    and perception
       Risk evaluation attempts to define what the estimated risk
        actually means to people concerned with or affected by the
        risk.

       A large part of this evaluation will be the consideration of
        how people perceive risks.

       We will provide an overview of the psychometric and cultural
        approaches underpinning risk perception, offering an
        insight into the reasons why risks are perceived in different
        ways.
+                                                                         38

    How safe is safe enough?

       ? = how safe is safe enough?

       An ERA will characterise the risk posed by a situation and then
        the process of risk management will eventually lead to a choice
        of action that will achieve the desired level of "safety".

       The determination of this "acceptable" or "tolerable" level of
        risk may have been prescribed before the risk assessment
        process begins - through societally determined acceptable
        levels of risk in the form of legislative environmental quality
        standards for instance, or industry derived "norms".

       In this case, risk management attempts to analyse which options
        for action based on the results of the risk assessment will
        produce these pre-determined risk levels.
+                                                          39




    What about where no acceptable risk standards exist?
+                                                                        40

       … the risk management process will attempt to derive
        ‘acceptable’ or tolerable risk on a case-by-case basis

       Thus

       Acceptable to whom?

       When risk assessment and management procedures are
        carried out by regulators or government, the aim is to
        produce societally acceptable risk levels.

       When an individual company carries out a risk assessment,
        in the absence of societally determined standards, risk levels
        will be determined which are acceptable to the company.
        These may have reference to societally acceptable levels or
        may be based on a formal risk-cost-benefit approach as
        advocated by some software packages on risk reduction.
+                                                                      41




    Decision making to determine "acceptable" or "tolerable" risk
     uses a number of approaches.

    The three major approaches to acceptable risk decisions

      -- are professional judgement where technical experts devise
      solutions,

      -- bootstrapping where historical precedent guides decision
      making

      -- formal analyses where theory-based procedures for
      modelling problems and calculating the best decision are used.

    These approaches are explained in detail in the readings.
+                                                                         42

    Risk management action

       Environmental risk can be:
           transferred to another body such as an insurance company,
           retained by a company or nation,
           eliminated by removal of the risk agent,
           reduced.

    In most environmental risk management conducted by nations
      on behalf of society, risk reduction will be the risk
      management option chosen. For individuals or companies,
      risk transfer is a common approach. This may be required by
      legislation, especially for infrequent catastrophic events. Risk
      elimination is often very difficult because of all the social and
      economic effects the removal of an agent can create.
+                                                                                               43

    Risk reduction?
        substitution
           Can the agent be substituted by another, less risky agent? For instance, can a
            chemical pesticide be substituted by a biological method? What are the risks
            of the new agent being introduced into the scenario? Is the new agent as
            effective?

        information
           Providing information about the safe use and disposal of agents will try to
            ensure that the risks assessed are the same as what actually occur in practice.

        information
           Education and information may also allow the public and users to choose lower
            risk options and force the manufacturers into the production of less risky
            agents.

       --> marketing
           Limit the availability of the agent by marketing bans or limits on the production
            or importation of the agent. Such a risk reduction technique has severe
            implications politically and economically and can often be controversial. Such
            decisions are taken at a national or regional level and at an international level
            such agreements are difficult to obtain.
+                                                             44

    New directions

       Risk Assessment:
           Harmonisation of risk assessment methods
           Data deficiencies and gaps
           Harmonisation of test protocols for chemicals
           Understanding of mixtures or multiple stressors
           Improvement of exposure assessment
           Internationally harmonised assessment factors
           Speeding up risk assessments
+                                                                       45

    New Directions

       Risk Management:
           Development of explicit methodologies for risk management
           Increased transparency of decision-making
           Peer review of risk management assessments
           Increased participation in risk management
+                                                                              46

    Risk Communication

       Reminder: Risk communication is defined in its simplest
        form as “any public or private communication that informs
        individuals about the existence, nature, form, severity, or
        acceptability of risks”

       As we’ll see, it actually involves more than that!

       From a technical perspective,
           risk assessment = the evaluation of the degree of harm or
            danger from some condition such as exposure to a toxic chemical,
           while risk management = the implementation of steps to reduce
            the danger to the public and the environment
+                                                                                         47

    Risk assessment - again
       Risk = Severity x Likelihood

       a technical, four-step procedure:

       Hazard identification. What is the potential source of danger? For example, does
        a waste incinerator emit highly toxic dioxins or other hazardous chemicals?

       Assessment of human exposure. Are any human populations exposed to this
        hazard? If so, can the various routes or pathways of the hazardous substance to
        specific organs or tissues of human bodies be traced? Finally, how much (what
        dosage) of this substance enters these human bodies?

       Modeling of the dose responses. What is the relationship between the dosage
        that is received and harmful responses or illnesses in the exposed population?

       Characterization of the overall risk. What are the overall implications of the dose
        responses for the health of the exposed population?

       Technical models of risk assessment use the resulting numerical value as the
        basis for judgments of what is an “acceptable risk. This judgment involves
        values.
+                                                                               48

    Limitations of technical model

       exceedingly difficult to trace the “pathway

       need to show direct correlation between particular
        chemicals and the specific illnesses

       Cultural-Experiential Model of Risk
           technical models conflate numerical risk (expected annual
            mortality) with judgments about the experience of those forced to
            live with imposed or involuntary risks
           big difference between those who take risks and those who are
            victimized by risks others take
+                                                                       49

    ‘hazard’ versus ‘outrage’

       experts often make assumptions about environmental risks
        that are quite removed from the experience of those affected
        by these risks

       the context in which a risk is embedded raises a number of
        questions that may affect one’s judgment of whether a risk is
        acceptable or not:
           Is the risk imposed by distant or unknown officials?
           Is it engaged in voluntarily?
           Is it reversible?
+                                                                                50

    Sandman’s proposal

       Risk = hazard + outrage
           Hazard is what experts mean by risk (expected annual mortality)
           Outrage should refer collectively to those factors that the public
            considers in assessing whether their exposure to a hazard is
            acceptable
                   Voluntariness
                   Control
                   Fairness
                   Process
                   Diffusion in time & space
+                                                                           51

    Problem with the Sandman
    proposal?
    This deceptively simple formula [risk equals hazard plus outrage] has
      become a staple in PR industry discussions of risk communication.
      … By understanding that risk equals hazard plus outrage, [Thomas]
      Buckmaster [general manger of the PR firm Hill & Knowlton] says,
      risk communicators can overcome the fear and hostility of
      “grassroots members, stakeholders, and the public at large.” …
      Once people are outraged, they don’t listen to hazard statistics …
      don’t use numerical risk comparisons.”

    In fact, he says, “managing the outrage is more important than
      managing the risk.”
+                                                                                 52

    Cultural rationality and risk

       cultural rationality include personal, familiar, and social concerns in
        evaluating a real risk event
+           Technical Rationality    Cultural Rationality               53


    Trust in scientific methods,     Trust in political culture and
    explanations; evidence           democratic process
    Appeal to authority and          Appeal to folk wisdom, peer
    expertise                        groups, and traditions
    Boundaries of analysis are       Boundaries of analysis are
    narrow and reductionistic        broad; include the use of
                                     analogy and historical precedent
    Risks are depersonalized         Risks are personalized

    Emphasis on statistical variation Emphasis of the impact of risks
    and probability                   on the family and community
    Appeal to consistency and        Focus on particularity; less
    universality                     concerned about consistency
    Those impacts that cannot be     Unanticipated or unarticulated
    uttered are irrelevant           risks are relevant
+                                                                  54

    Communication models

    Two quite different models of risk communication that have
     emerged since the late 1980s, reflecting the technical and
     cultural meanings of risk we have thus discussed:

    The traditional, technical model of risk communication seeks
      to translate numerical characterizations of risk to public
      audiences,

    while the cultural model of risk communication draws upon
     the experiences and local knowledge of affected
     communities as well as laboratory models, doses, and
     pathways of exposures
+                                                                           55

      Technical Risk Communication

   the translation of technical data about environmental or health
    risks for public consumption, with the goal of educating a target
    audience

   one-way transfer of information

   goal: to inform, change, and (sometimes) to assure
      1.    Inform local communities of an environmental or health hazard
           Importantly, technical risk communication occurs after an
              assessment has been made of the health effects of an
              environmental hazard
      2.    change risky behavior
      3.    Assure those exposed to a perceived hazard that the risk is
            “acceptable
+                                                                      56

    Technical Risk Communication

       in the US, Agency officials tend to assume that individuals
        underestimate the dangers of personal health behaviors such
        as not wearing seat belts, smoking, etc.,

       but in environmental affairs, the logic is reversed—agencies
        assume that individuals have “exaggerated” fears about
        chemical hazards, etc

       * in Lebanon?
+                                                                                57

    Cultural model of risk
    communication
     3 areas where the public’s intuitive and experiential judgments
       differed most from technical risk analysis:
     1.   “concern about low-probability but high consequence events;”
          for example, a 1 percent chance that an accident will occur, but a
          terrible toll of death should it happen.
     2.   a “desire for consent and control in social management of risks;”
          the public’s feeling that they have a say in decisions about risk is
          the opposite of a coerced or involuntary imposition of risk.
     3.   “the relationship of judgments about risk to judgments about
          social institutions;” in other words, the acceptability of risk may
          depend on how confident citizens are in the institution that is
          conducting a study, managing a facility, or monitoring its safety.
+                                                                                    58

    Citizen participation in risk
    communication
       US National Research Council: understanding of environmental
        risk requires “a broad understanding of the relevant losses,
        harms, or consequences to the interested and affected parties,
        including what the affected parties believe the risks to be in
        particular situations”

       Critical rhetoric for risk communication … 3 principles
           sees risk as socially constructed and rhetorical … The meaning and
            value of risk in a given situation is [sic] a function of multiple and
            sometimes competing discourses. …
           focuses on the processes of decision making … [especially] on the
            relations of power within decision making processes, asking
            questions about who participates and in whose interests decisions are
            made.
           seeks to contextualize and localize risk situations … [by encouraging]
            local participation.
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    Media Reporting of Risk

       What factors influence what is reported about environmental
        risk? What factors influence whose voices are presented in
        the story?

       Media Reports of Risk: Accurate Information or Sensational
        Stories?
           low probability, but high consequence” occurrences
           What are your thoughts about sensationalized risk news?
           Voices of side effects…
               those individuals (or their children) who suffer the “side
                effects” of the risk society such as asthma and other illnesses
                from air pollutants, chemical contamination, etc

				
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posted:8/9/2012
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