Risk Management: A Conceptual Introduction Tee L. Guidotti Occupational Health Program University of Alberta

Dimensions of Risk Management Risk perception Risk communication Risk control –structural change –reduce exposure –reduce potential loss or liability Risk anticipation Risk comparison

What is Risk - Really? A conceptual abstraction - “risk” does not exist per se Risk is a description of the behaviour of a system, either in past or predicted Risk reflects characteristics of the system, subject to change Risk is fundamental to change or adaptation All society is about mitigating risk

Levels of Risk Legal standard of certainty Allowable scientific error Clinical complications Public health (e.g. vaccine safety) De minimis (p value)

Risk Perception

Public view of risk may not match that of experts People tend to estimate risk best in the middle of the range - they distort the extremes Risk perception is laden with values learned in society and the family Risk perception is culturally determined Risk is perceived as good in many contexts

Risk Communication

Cardinal Rules for Risk Communication Accept, involve public as legitimate partner Plan carefully and evaluate performance Listen to the audience Be honest, frank and open Coordinate, collaborate with other credible sources Meet the needs of the media Speak clearly and with compassion After Covello; originally prepared for U.S. EPA.

Risk control structural change –engineering and environmental change –replacement reduce exposure –protection –isolation reduce potential loss (mitigate effects) reduce potential liability

Achieving Risk Control Market incentives Regulation Voluntary compliance –may involve mutual coercion –role of guidelines –indirect regulation Cultural norms

Risk Control through Regulation

Regulatory Options

Standards v. Guidelines Standards Legal authority usually delegated Binding Mandatory compliance Enforceable Universal application Consultation process Guidelines Authority usually negotiated Advisory Voluntary compliance No sanctions Discretionary Multistakeholder process

Examples of Standards - US

Examples of Guidelines - US

Standards and Guidelines in Canada

Establishing Exposure Standards Occupational v. environmental (assumptions of vulnerability) General benchmark required –risk based –non-degradation (historical) –reference level,  NOAEL/safety factor –technology-driven Appropriate model for extrapolation

How Standards Are Set - U.S. EPA as an Example

Two Models for Standard Setting Noncarcinogens (direct effects model) Carcinogens (stochastic model) These standards-setting models flow logically from the risk assessment models used for each.

Model: Non-Carcinogens Standards for non-carcinogens typically assume a toxicologic exposure-response relationship –based on known exposure-response slope –identify NOAEL, extrapolate to humans –safety factors (uncertainty factors) Acceptable risk is below chronic toxicity level for most vulnerable subgroups

RfD = NOAEL/(UF 1  … Uf n )

Safety Factors (US EPA)

Model for Carcinogens Stochastic model, derive maximum likelihood estimate or UCL of frequency-response slope Derive unit cancer risk, q1* Individual lifetime cancer risk = exposure  slope Adjust allowable exposure to de minimis risk level (  10 –5 )

Implications of Model for Carcinogens Because risk level is preset, little flexibility Safety factors do not apply Low-dose extrapolation: on-going debate Tends to drive standards-setting in mixtures of carcinogenic, non-carcinogenic agents –benzene in Cdn drinking water guidelines –benzene drives BTEX-based evaluations –PAHs drive CCME guidelines

Historical Derivation of Standards Consensual process or majority of an authoritative group Based on review of the evidence Considerable debate in camera Issues of role and conflict of interest Problem of disinterested expert Disillusionment and opening of process

Risk Anticipation New idea, in evolution Anticipate risk before it becomes a management problem Requires internal culture of skepticism

Risk Comparison A systematic process of consultation in an open, multistakeholder process –expert panels –public(s) Iterative process in open discussion Consensus on magnitude of risks Consensus on priorities and ranking of risks

Risk Comparison Benefits Consensus, once achieved, is solid Broadly inclusive Educates constituencies Direct guidance for public priorities, e.g. budgets Provides framework for NGO participation Drawbacks Very time consuming Easily hijacked Requires active outreach to constituencies NGOs may lead public NGOs may not be representative of public opinion