Environmental Risk Assessment Environmental risk assessment (EnRA) deals with the interactions of agents or hazards, humans and ecological resources. It describes human populations, ecological resources and agents, analyzes agents and exposure potential, characterizes the potential for adverse effects, defines uncertainties, generates options to deal with the risks, and communicates information about the risks to humans and ecosystems.

Loss Exposures Property loss:  Real and personal property can be damaged or contaminated.  Even after cleanup, the value of the property may be seriously degraded.  Personnel loss:  Environmental exposure limits allow a much smaller level of acceptable risk.  Further, environmental exposures may contribute to the overall body burden of workers and should be considered along with occupational exposures when assessing personnel risk of loss. Net income loss:  Besides the loss of business income from interruption, there is also the possibility of a court injunction ceasing operations.

Hazards Chemicals toxic to humans, animals, and plants; Materials that are highly flammable or explosive; Mechanical equipment, the failure of which would endanger persons and property; Structural failure (e.g., dam or containment vessel); Natural disasters that exacerbate technological hazards; Ecosystem damage (e.g., eutrophication, soil erosion).

Examples of information about hazards Potential release of hazardous chemicals (rate and amount); Accidental fires and explosions; Transport and fate of pollutants in the environment; Dilution-dispersion mechanisms and rates; Exposure to toxins (who, how many, how much); Dose-response predictions based on animal tests; Failure rates of mechanical equipment or structures; Human behavior (errors by workers, public reaction); Natural hazards (earthquake, tsunami, typhoon); Alterations in drainage patterns, water table, vegetation, microclimate.

Uncertainties Lack of understanding of important cause-effect relationships, lack of scientific theory; Models that do not correspond to reality; Weaknesses in available data; Data gaps; Toxicological data that are extrapolated; Natural variation in environmental parameters; Necessary assumptions on which estimates are based, and the sensitivity of the resulting estimates to changes in the assumptions; Novelty of the project.

Environmental Risk Assessment The risk assessment process consists of several steps: Hazard Identification/Release Assessment: using tools such as hazard indices, Hazop, event tree analysis, failure mode and effect analysis and many others to determine the nature of potential hazards and the likelihood of a release(software, databases); Exposure Assessment attempts to determine the magnitude of the physical effects of an undesirable event (identified in the hazard identification and release assessment stages), and the pathways and transport modes of the hazard to the receptor, using predictive exposure modelling tools for aerosols, thermal radiation, vapor cloud explosions etc...(software) Consequence Assessment attempts to quantify the possible damage to the receptor, caused by the exposure to the hazard, using vulnerability models (software); Risk Estimation consists of integrating the estimation of the probability of release events with the results of the consequence assessment to produce an estimate of the overall risk of an activity.

EU Risk Assessment Model The EU Environmental Risk Assessment consists of four steps Hazard identification –where the adverse effects that a chemical has an inherent capacity to cause are indicated; Dose - response assessment - the relationship between dose or level of exposure of the substance and the severity of an effect are estimated; Exposure assessment – estimation of the concentration to which environmental compartments are or may be exposed. The sources, emission routes and degradation pathways of the chemical are also determined; Risk characterization - estimation of the incidence and severity of the effects likelihood to occur in an environmental compartment due to actual or predicted exposure to a chemical.

Conceptual Model of Environmental Risk

Risk Characterization EPA's Exposure Assessment Guidelines define risk characterization as the final step in the risk assessment process that: Integrates the individual characterizations from the hazard identification, dose-response, and exposure assessments; Provides an evaluation of the overall quality of the assessment and the degree of confidence the authors have in the estimates of risk and conclusions drawn; Describes risks to individuals and populations in terms of extent and severity of probable harm; and Communicates results of the risk assessment to the risk manager.

Classes of Environmental Risk Assessments The EPA classifies environmental risk assessments into one of two areas: Human Health Ecological

Human Risk Assessment A human health risk assessment is the process to estimate the nature and probability of adverse health effects in humans who may be exposed to chemicals in contaminated environmental media, now or in the future.

Human Health Risk Assessment Human health risk assessment includes 4 basic steps: Step 1 - Hazard Identification Examines whether a stressor has the potential to cause harm to humans and/or ecological systems, and if so, under what circumstances. Step 2 - Dose-Response Assessment Examines the numerical relationship between exposure and effects. Step 3 - Exposure Assessment Examines what is known about the frequency, timing, and levels of contact with a stressor. Step 4 - Risk Characterization Examines how well the data support conclusions about the nature and extent of the risk from exposure to environmental stressors.

Ecological An ecological risk assessment is the process for evaluating how likely it is that the environment may be impacted as a result of exposure to one or more environmental stressors such as chemicals, land change, disease, invasive species and climate change.

Ecological Risk Assessment An ecological risk assessment includes 3 phases: Phase 1 - Problem Formulation Information is gathered to help determine what, in terms of plants and animals, is at risk and what needs to be protected. Phase 2 – Analysis This is the determination of what plants and animals are exposed and to what degree they are exposed, and if that level of exposure is likely or not to cause harmful ecological effects. Phase 3 - Risk Characterization Risk characterization includes two major components: risk estimation and risk description. “Risk estimation" combines exposure profiles and exposure-effects. "Risk description" provides information important for interpreting the risk results and identifies a level for harmful effects on the plants and animals of concern.

Risk Assessment Uses in Policy Development The use of risk assessment and management techniques in policy and regulatory decisions Risk assessment and management approaches to environmental issues are increasingly being used at all levels of policy and regulation. The techniques have a wide range of application, including; The design of regulation, for instance in determining societally "acceptable" risk levels which may form the basis of environmental standards; Providing a basis for site-specific decisions, for instance in land-use planning or siting of hazardous installations; Prioritization of environmental risks, for instance in the determination of which chemicals to regulate first; Comparison of 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

ERA is Uses in Industry ERA can be used in industry to accomplish the following: Compliance with legislation Product safety Financial planning Site-specific decision making Prioritization and evaluation of risk reduction measures

Environmental Risk Control Strategies ISO 14001 ISO 14001 was developed primarily to assist companies with a framework for better management control that can result in reducing their environmental impacts. The Eco-Management and Audit Scheme (EMAS) A voluntary tool available to any organization operating within or outside the European Union that wants to: assume environmental and economic responsibility; improve its environmental performance; communicate its environmental results to society and stakeholders in general.

Environmental Risk Communication Risk communication is the process of informing people about potential hazards to their person, property, or community. Risk communication is the act of conveying or transmitting information between parties about a range of areas including: levels of health or environmental risks the significance or meaning of health or environmental risks decisions, actions or policies aimed at managing or controlling health or environmental risks.

Environmental Risk Communication Risk communication, unlike many other communications, often involves statements about threatening and poorly understood hazards and consequently, the dialog is often riddled with disagreements, apathy, misunderstanding, and suspicion (Rowan 1994).

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