ecological risk assessment (era)

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1 ECOLOGICAL RISK ASSESSMENT Sa’ari Mustapha, Faculty of Engineering Universiti Putra Malaysia 1. INRODUCTION 2. BASIC CONCEPT 2.1. Definition 2.2. Fundamental distraction between ecological risk and Environmental Impact Assessment 3.3. Definition of Environmental and Ecological Risk Assessment 3.4. Regulatory forces driving ERA 3. FRAMEWORK FOR ERA 3.1. US EPA 3.2. The Characterization, ecological effect of environmental exposure the hazards human activities 3.2.1. Hazards identification 3.2.2. Exposure assessment 3.2.3. Exposure-response assessment 3.2.4. Risk characterization 3.3. Water Environment Research Foundation Application 3.3.1. Screening -level Risk Assessment 3.3.2. Risk quantification with existing 4. COMPARATIVE RISK ASSESSMENT 5. SUMMARY 6. CONCLUSION 7. REFERENCES 1. Sa’ari Mustapha, PhD, CEng.,CSci., CEnv., MIChemE.,AMIC, OKMH Fakulti Kejuruteraan, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor. Tel:03-89466303 Fax:03-86567120 E-mail:saari@eng. Upm.edu.my 2. Mohd Kamil Yusoff, PhD Fakulti Pengajian Alam Sekitar, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor. 3. Mohammad Firuz Ramli, PhD Fakulti Pengajian Alam Sekitar, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor.

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ECOLOGICAL RISK ASSESSMENT Sa’ari Mustapha, Faculty of Engineering Universiti Putra Malaysia

1. INRODUCTION 2. BASIC CONCEPT

2.1. Definition 2.2. Fundamental distraction between ecological risk and Environmental Impact Assessment 3.3. Definition of Environmental and Ecological Risk Assessment 3.4. Regulatory forces driving ERA

3. FRAMEWORK FOR ERA 3.1. US EPA 3.2. The Characterization, ecological effect of environmental exposure the hazards human activities

3.2.1. Hazards identification 3.2.2. Exposure assessment 3.2.3. Exposure-response assessment 3.2.4. Risk characterization

3.3. Water Environment Research Foundation Application 3.3.1. Screening -level Risk Assessment 3.3.2. Risk quantification with existing

4. COMPARATIVE RISK ASSESSMENT 5. SUMMARY 6. CONCLUSION 7. REFERENCES

1. Sa’ari Mustapha, PhD, CEng.,CSci., CEnv., MIChemE.,AMIC, OKMH Fakulti Kejuruteraan, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor. Tel:03-89466303 Fax:03-86567120 E-mail:saari@eng. Upm.edu.my 2. Mohd Kamil Yusoff, PhD

Fakulti Pengajian Alam Sekitar, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor.

3. Mohammad Firuz Ramli, PhD Fakulti Pengajian Alam Sekitar, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor.

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4. INTRODUCTION

Ecological risk assessment (ERA) was applied as assessment tool on the environment since 1970 (Ball, 2002). Initially it was used to assess the risk of human health in Europe and USA since 1960 (Bridges, 2003). Since then the technique has been used to assess the environmental impact products in agricultural, chemical, process and petroleum industries and other sectors environmental management of effluent discharge, finance, health and medicine, ecotoxicology, military and aerospace operation, natural disaster, transport and industrial safety sectors (Karman, 2000; Bridges, 2003; Ball, 2002, Griffiths, 2002). This article is emphasized on the ecological risk assessment. An ecological risk assessment is a process that evaluates the likelihood that adverse ecological effects may occur or are occurring as a result of exposure to one or more stressors (US EPA, 1992a, 1998). The process is used to systematically evaluate and organize data, information, assumptions, and uncertainties to help understand and predict the relationships between stressors and ecological effects in a way that is useful for environmental decision-making. Ecological risks can be assessed through field studies; however, performing a large number of these studies may be inappropriate because of the expense in sacrificing receptors and overall cost in obtaining field data. Because of the variety of habitats and species in an ecosystem and the associated interactions between biota and physical–chemical conditions, risk assessment is a complex process.

In Malaysia ERA is a prerequisite in Environmental Impact Assessment (EIA) report in almost process industries as specified under EIA regulations (1994). It also part of requirement in the Safety Report under the Occupational Safety and Health (Control of Industrial Major Accident Hazards) regulations or CIMAH regulations, 1996 and a requirement for the Occupational Safety and Health (Chemical Health Risk Assessment) regulations 2000 to evaluate risk of chemical exposure.

Environmental is interpreted broadly that is including people as basic component, air, water, soil flora and fauna. These components are susceptible to harm or may deteriorate their quality if continuously or frequently expose to the pollutants or contaminants due human activity or natural phenomena. The word risk basically applied to undesirable outcomes as distinct from the beneficial ones (Griffith, 2002). Risk is always defined as result from the probability of occurrence multiply by its consequence. The cumulative of risk from the various incident scenarios and events is also used to quantify the risk. Fatality rate, failure rate and risk index are among parameters used to indicate the risk level. Other terms are such as property damage (e.g. glass broken and building collapse), level of injury (e.g. first burn, second burn, lung hemorrhage, damage and toxicity (LD50 and LC50).

Risk assessment is used to assess the risk impacts at various distances from the proposed development and on various land uses and the environment on vicinity (DoP, 1991). The Environmental Protection Agency (1991) or EPA had applied the risk assessment to establish priorities for contaminated land remediation. European country (EC) enforced the Commission Directive 93/67/EEC on 20 July 1993 that defined four different stages in risk assessment process viz. hazard identification, dose(concentration)-response (effect) assessment, exposure assessment and risk characterization. The directive was introduced for assessing the risk to man and the environment for new chemical substances. In fact the hazardous materials should not be limited or imposed to new products but also all a range of materials from raw material, intermediate, product and waste. The most important is to identify the source or harm of exposure of the materials and then assess their pathways or routes to the environment and impact to receptors or target. For

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example, leak of a flammable material can expose to risk of fire or explosion and the accident can cause fatality or damage the property and the environment. 2. BASIC CONCEPT In recent years, ecological risk assessment (ERA) has emerged as an important part of environmental protection programs. The following discussion provides a brief overview of ERA issues. 2.1. Definition ERA is the practice of determining the nature and likelihood of effects of our actions on animals, plants, and the environment. (In Europe, the term “Environmental Risk Assessment” is often used.) Ecological risk assessments deal with human-caused changes that alter important features of ecological systems such as lakes, streams, forests, or watersheds. When we introduce a new chemical (such as a pesticide to a wheat field), accidentally import a new species (such as a foreign insect), or change a landscape (such as draining or filling a wetland), scientists often assess how much damage those actions may have on the plants or animals in the area. Ecological risks may be local a hazardous waste site. The risks may be regional the Chesapeake Bay, the Black Forest, or the Great Barrier Reef. The risks may be global atmospheric transport of chemicals or global warming. Ecological risks may involve a specific type of plant or animal (a bass), a community of organisms (the fish in a lake), or an ecosystem (all of the biological and physical components of the lake). 2.2. Fundamental distraction between ecological risk and Environmental Impact

Assessment Ecological risks are 1) estimated from the relationship between exposure and effects and 2) made with varying degrees of uncertainty. ERAs evaluate two basic elements: exposure and effects. 1) Exposure is the interaction of stressors with receptors. Measures of exposure can

include concentrations of contaminants or physical changes in habitat. 2) The analysis of effects evaluates changes in the nature and magnitude of effects as

exposure changes.

Figure 1. ERA’s Basic Concepts

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Integrating exposure and effects information leads to an estimation of risk, the likelihood that adverse effects will result from exposure (Figure 1). Approaches for evaluating exposure and effects include, for example, measuring chemical releases, predicting with models the environmental fate and effects of chemicals even before they are manufactured, and testing effects of these chemicals in a laboratory. Exposure and effects must be considered together because they are both important in estimating risk. When the potential for exposure and effects is low, the risk will be low. When both are high, the risk will be high. Whatever the approach, the goal is to use all available information to characterize exposure and effects and to integrate them into an understanding of ecological risks. Because of the complexity of nature, risk assessment will include some degree of uncertainty. Although we can reduce some components of uncertainty by gathering additional data, we can only estimate other components due to their inherent variability (such as rainfall and temperature variations). While it is important for risk managers to understand the impact of natural variability and uncertainty on the conclusions of the risk assessment, making a risk management decision does not require the absence of uncertainty. In fact, an attempt is made to quantify and communicate uncertainty when conducting and reporting ERAs so that the best decisions can be made with our current state of knowledge. 2.3. Definition of Environmental and Ecological Risk Assessment Environmental is interpreted broadly that is including people as basic component, air, water, soil flora and fauna. These components are susceptible to harm or may deteriorate their quality if continuously or frequently expose to the pollutants or contaminants due human activity or natural phenomena. Ecological Risk Assessment is the practice of determining the nature and likelihood of effects of our actions on animals, plants, and the environment. Industry, government agencies, policy makers, citizens, and legislators use ERA to support environmental management decisions. ERA helps organize information and contributes to informed decisions. It is a useful risk management tool that • highlights the greatest risks, which is helpful for allocating limited resources; • allows decision makers to ask “what if” questions regarding the consequences of

potential management actions; • facilitates explicit identification of environmental values of concern; and • identifies critical knowledge gaps, thereby helping to prioritize future research needs. ERA can be used to evaluate relative benefits of different clean-up options at hazardous waste sites, screen new chemicals prior to their commercial production, evaluate the risks that imported agricultural products may introduce exotic agricultural pests, or determine the threats to valued ecological resources in a watershed. ERAs include the following: 1) Problem formulation: clearly defining the problem 2) Analysis: characterizing potential or existing exposure to stressors and their effects 3) Risk characterization: integrating and evaluating exposure and effects information. Planning the assessment with the risk manager and communicating the risks to decision-makers are important parts of the process. The diagram to the right, from the USEPA’s Proposed Guidelines for Ecological Risk Assessment, illustrates one of ERA’s strengths: a generally accepted standard framework.

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2.4. Regulatory forces driving ERA The U.S. Environmental Protection Agency (EPA) is today publishing in final form a document entitled Guidelines for Ecological Risk Assessment (hereafter “Guidelines”). These Guidelines were developed as part of an interoffice program by a Technical Panel of the Risk Assessment Forum. These Guidelines will help improve the quality of ecological risk assessments at EPA while increasing the consistency of assessments among the Agency’s program offices and regions. These Guidelines were prepared during a time of increasing interest in the field of ecological risk assessment and reflect input from many sources both within and outside the Agency. The Guidelines expand upon and replace the previously published EPA report Framework for Ecological Risk Assessment (EPA/630/R-92/001, February 1992), which proposed principles and terminology for the ecological risk assessment process. From 1992 to 1994, the Agency focused on identifying a structure for the Guidelines and the issues that the document would address. EPA sponsored public and Agency colloquia, developed peer-reviewed ecological assessment case studies, and prepared a set of peer reviewed issue papers highlighting important principles and approaches. Drafts of the proposed Guidelines underwent formal external peer review and were reviewed by the Agency’s Risk Assessment Forum, by Federal interagency subcommittees of the Committee on Environment and Natural Resources of the Office of Science and Technology Policy, and by the Agency’s Science Advisory Board (SAB). The proposed Guidelines were published for public comment in 1996 (61 FR 47552-47631, September 9, 1996). Ecological risk assessment “evaluates the likelihood that adverse ecological effects may occur or are occurring as a result of exposure to one or more stressors” (U.S. EPA, 1992a). It is a flexible process for organizing and analyzing data, information, assumptions, and uncertainties to evaluate the likelihood of adverse ecological effects. Ecological risk assessment provides a critical element for environmental decision making by giving risk managers an approach for considering available scientific information along with the other factors they need to consider (e.g., social, legal, political, or economic) in selecting a course of action. To help improve the quality and consistency of the U.S. Environmental Protection Agency’s ecological risk assessments, EPA’s Risk Assessment Forum initiated development of these Guidelines. The primary audience for this document is risk assessors and risk managers at EPA, although these Guidelines also may be useful to others outside the Agency. These Guidelines expand on and replace the 1992 report Framework for Ecological Risk Assessment. They were written by a Forum technical panel and have been revised on the basis of extensive comments from outside peer reviewers as well as Agency staff. The Guidelines retain the Framework Report’s broad scope, while expanding on some concepts and modifying others to reflect Agency experiences. EPA intends to follow these Guidelines with a series of shorter, more detailed documents that address specific ecological risk assessment topics. This “bookshelf” approach provides the flexibility necessary to keep pace with developments in the rapidly evolving field of ecological risk assessment while allowing time to form consensus, where appropriate, on science policy (default assumptions) to bridge gaps in knowledge. EPA will revisit guidelines documents as experience and scientific consensus evolve. The Agency recognizes that ecological risk assessment is only one tool in the overall management of ecological risks. Therefore, there are ongoing efforts within the Agency to develop other tools and processes that can contribute to an overall approach to ecological risk management, addressing topics such as ecological benefits assessment and

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cost-benefit analyses. Ecological risk assessment includes three primary phases: problem formulation, analysis, and risk characterization. In problem formulation, risk assessors evaluate goals and select assessment endpoints, prepare the conceptual model, and develop an analysis plan. During the analysis phase, assessors evaluate exposure to stressors and the relationship between stressor levels and ecological effects. In the third phase, risk characterization, assessors estimate risk through integration of exposure and stressor-response profiles, describe risk by discussing lines of evidence and determining ecological adversity, and prepare a report. The interface among risk assessors, risk managers, and interested parties during planning at the beginning and communication of risk at the end of the risk assessment is critical to ensure that the results of the assessment can be used to support a management decision. Because of the diverse expertise required (especially in complex ecological risk assessments), risk assessors and risk managers frequently work in multidisciplinary teams. Both risk managers and risk assessors bring valuable perspectives to the initial planning activities for an ecological risk assessment. Risk managers charged with protecting the environment can identify information they need to develop their decision, risk assessors can ensure that science is effectively used to address ecological concerns, and together they can evaluate whether a risk assessment can address identified problems. However, this planning process is distinct from the scientific conduct of an ecological risk assessment. This distinction helps ensure that political and social issues, while helping to define the objectives for the risk assessment, do not introduce undue bias. Problem formulation, which follows these planning discussions, provides a foundation upon which the entire risk assessment depends. Successful completion of problem formulation depends on the quality of three products: assessment endpoints, conceptual models, and an analysis plan. Since problem formulation is an interactive, nonlinear process, substantial reevaluation is expected to occur during the development of all problem formulation products. The analysis phase includes two principal activities: characterization of exposure and characterization of ecological effects. The process is flexible, and interaction between the two evaluations is essential. Both activities evaluate available data for scientific credibility and relevance to assessment endpoints and the conceptual model. Exposure characterization describes sources of stressors, their distribution in the environment, and their contact or co-occurrence with ecological receptors. Ecological effects characterization evaluates stressor- response relationships or evidence that exposure to stressors causes an observed response. The bulk of quantitative uncertainty analysis is performed in the analysis phase, although uncertainty is an important consideration throughout the entire risk assessment. The analysis phase products are summary profiles that describe exposure and the stressor-response relationships. Risk characterization is the final phase of an ecological risk assessment. During this phase, risk assessors estimate ecological risks, indicate the overall degree of confidence in the risk estimates, cite evidence supporting the risk estimates, and interpret the adversity of ecological effects. To ensure mutual understanding between risk assessors and managers, a good risk characterization will express results clearly, articulate major assumptions and uncertainties, identify reasonable alternative interpretations, and separate scientific conclusions from policy judgments. Risk managers use risk assessment results, along with other factors (e.g., economic or legal concerns), in making risk management decisions and as a basis for communicating risks to interested parties and the general public. After completion of the risk assessment, risk managers may consider whether follow-up activities are required. They may decide on risk mitigation measures, then develop a

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monitoring plan to determine whether the procedures reduced risk or whether ecological recovery is occurring. Managers may also elect to conduct another planned tier or iteration of the risk assessment if necessary to support a management decision. 3. FRAMEWORK FOR ERA The ecological risk assessment process is based on two major elements: characterization of effects and characterization of exposure. These provide the focus for conducting the three phases of risk assessment: problem formulation, analysis, and risk characterization. The overall ecological risk assessment process is shown in Figure 2. The format remains consistent with the diagram from the 1992 report Framework for Ecological Risk Assessment. The framework process (Figure 2.) is a general representation of a complex and varied group of assessments. This diagram represents a flexible process, as illustrated by the examples below. In problem formulation, an assessment may begin with a consideration of endpoints,

stressors, or ecological effects. Problem formulation is generally interactive and iterative, not linear.

In the analysis phase, characterization of exposure and effects frequently become intertwined, as when an initial exposure leads to a cascade of additional exposures and secondary effects. The analysis phase should foster an understanding of these complex relationships.

Analysis and risk characterization are shown as separate phases. However, some models

may combine the analysis of exposure and effects data with the integration of these data that occurs in risk characterization.

However, the process and products within each phase have been refined, and these changes are detailed in Figure 3. The three phases of risk assessment are enclosed by a dark solid line. Boxes outside this line identify critical activities that influence why and how a risk assessment is conducted and how it will be used. Problem formulation, the first phase, is shown at the top. In problem formulation, the purpose for the assessment is articulated, the problem is defined, and a plan for analyzing and characterizing risk is determined. Initial work in problem formulation includes the integration of available information on sources, stressors, effects, and ecosystem and receptor characteristics. From this information two products are generated: assessment endpoints and conceptual models. Either product may be generated first (the order depends on the type of risk assessment), but both are needed to complete an analysis plan, the final product of problem formulation. Analysis, shown in the middle box, is directed by the products of problem formulation. During the analysis phase, data are evaluated to determine how exposure to stressors is likely to occur (characterization of exposure) and, given this exposure, the potential and type of ecological effects that can be expected (characterization of ecological effects). The first step in analysis is to determine the strengths and limitations of data on exposure, effects, and ecosystem and receptor characteristics. Data are then analyzed to characterize the nature of potential or actual exposure and the ecological responses under the circumstances defined in the conceptual model(s). The products from these analyses are two profiles, one for exposure and one for stressor response. These products provide the basis for risk characterization.

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Figure 2. The framework for ecological risk assessment (modified from U.S. EPA, 1992a).

During risk characterization, shown in the third box, the exposure and stressor-response profiles are integrated through the risk estimation process. Risk characterization includes a summary of assumptions, scientific uncertainties, and strengths and limitations of the analyses. The final product is a risk description in which the results of the integration are presented, including an interpretation of ecological adversity and descriptions of uncertainty and lines of evidence. Although problem formulation, analysis, and risk characterization are presented sequentially, ecological risk assessments are frequently iterative. Something learned during analysis or risk characterization can lead to a reevaluation of problem formulation or new data collection and analysis. Interactions among risk assessors, risk managers, and other interested parties are shown in two places in the diagram. In Figure 2, the side box on the upper left represents planning, where agreements are made about the management goals, the purpose for the risk assessment, and the resources available to conduct the work. The box following risk characterization represents when the results of the risk assessment are formally communicated by risk assessors to risk managers. Risk managers generally communicate risk assessment results to interested parties. These activities are shown outside the ecological risk assessment process diagram to emphasize that risk assessment and risk management are two distinct activities. The former involves the evaluation of the likelihood of adverse effects, while the latter involves the selection of a course of action

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in response to an identified risk that is based on many factors (e.g., social, legal, political, or economic) in addition to the risk assessment results.

Figure 3. The ecological risk assessment framework The bar along the right side of Figure 3 highlights data acquisition, iteration, and monitoring. Monitoring data provide important input to all phases of a risk assessment. They can provide the impetus for a risk assessment by identifying changes in ecological condition. They can also be used to evaluate a risk assessment’s predictions. For example, follow-up studies could determine whether mitigation efforts were effective, help verify whether source reduction was effective, or determine the extent and nature of ecological recovery. It is important for risk assessors and risk managers to use monitoring results to

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evaluate risk assessment predictions so they can gain experience and help improve the risk assessment and risk management process (Commission on Risk Assessment and Risk Management, 1997). Even though the risk assessment focuses on data analysis and interpretation, acquiring the appropriate quantity and quality of data for use in the process is critical. If data are unavailable, the risk assessment may stop until data are obtained. The process is more often iterative than linear, since the evaluation of new data or information may require revisiting a part of the process or conducting a new assessment. The dotted line between the side bar and the risk management box indicates that additional data acquisition, iteration, or monitoring, while important, are not always required. 3.1. US EPA The US Environmental Protection Agency (EPA) has statutory requirements to regulate various contaminants to protect human health and the environment. For each chemical, it is necessary to identify whether a chemical poses a risk, to determine the potency of the chemical, and to estimate the potential risk imposed by exposure to that contaminant. The process of estimating and characterizing potential risks from various chemicals is called risk assessment. Translation of the risk assessment into a regulation involves risk management. EPA informs the public of its actions through risk communication. This review will focus on risk assessment and will only briefly consider risk management and communication.

EPA has gained much experience with the ecological risk assessment process since the publication of the Framework Report (U.S. EPA, 1992a) and has received many suggestions for modifications of both the process and the terminology. While EPA is not recommending major changes in the overall ecological risk assessment process, modifications are summarized here to assist those who may already be familiar with the Framework Report. Changes in the diagram are discussed first, followed by changes in terminology and definitions. Risk assessment is the general process used to determine the potential risk of an adverse health effect occurring from exposure to an agent. It consists of a hazard identification, a dose-response evaluation, an exposure assessment and a risk characterization. At the U.S. Environmental Protection Agency, risk assessments are used to estimate risks from environmental contaminants. Risk management uses the risk characterization along with such variables as economic, social, legal, technical, analytical and political factors to arrive at a regulatory level. The public is informed of regulatory actions prior to and after promulgation of the final rule through the process of risk communication.

3.2. The Characterization, ecological effect of environmental exposure the hazards human activities

To perform a risk assessment, it is necessary to have a working definition of risk. Risk is considered to be the possibility of an injury, disease or death resulting from an dose-response assessment and exposure assessment to arrive at risk characterization. EPA is primarily concerned with those risks that occur after exposure to environmental compounds. Risk assessment is the effort made to estimate the risk associated with a

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specific set of conditions. EPA follows the risk assessment paradigm outlined by the National Academy of Sciences. They outlined risk assessment as being composed of a hazard identification, a dose-response evaluation and an exposure assessment which are integrated into a risk characterization (Figure 4). The resulting risk assessment may be quantitative and/or qualitative in nature. Some examples from the Safe Drinking Water Program will be used as illustrations.

Figure 4. Risk assessment paradigm demonstrates the relationships among hazard identification

3.2.1. Hazards Identification To identify a hazardous chemical, the toxicity data base of a chemical must be surveyed. The chemical in question must produce some adverse effect in humans or in experimental animals. As would be expected, most of the available toxicity data base is the result of animal studies. When using animal data, it is understood that the deleterious effects observed in animals will occur, or are expected to occur, in humans. Animal toxicity data may be acute (usually 1 exposure), subacute’ (14 days), subchronic (90 days) or chronic (2 years) for general toxicity studies, Other toxicity tests, such as reproductive, developmental and mutagenic assays use protocols specifically designed to examine that respective endpoint. Acute and subacute tests are only general indicators of toxicity and are not used to develop regulations for drinking water standards. As previously mentioned, data on the effects of chemicals on humans are not as plentiful as those on experimental animal. Most of the human data come from case reports, correlation assessments and occupational or epidemiological cohort studies. The most desirable and informative are the epidemiological cohort studies. They examine populations that have been exposed to an agent and compare them to a matched control population. This type of study is valuable since it provides information on humans exposed to environmental concentrations. Risk is a combination likelihood of occurrence of event and its severity or consequence. It is always considered to be functioned of the frequency or probability of an event and the consequence of occurrence of the event. This is the definition used in process industries for example to determine the probability and its effect to the environment. For example risk of fire, explosion and toxic release from a process plant. For the environmental risk assessment the definition is limited determination exposure

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assessment such as emission, pathways and rates of movement of a substance, its transformation and degradation in terms of concentration/dose in the air borne.

The risk is expressed in three ways: 1) Qualitatively for example high, medium, low, tolerable, intolerable and

acceptable; 2) Semi-quantitatively is principally based on likelihood and consequence

but then it ranked one against other e.g. major, intermediate and low risks; 3) Quantitatively by calculating the likelihood (frequency) and the

potential consequence of an event. The result is presented in the form of figure e.g. fatality/year

Risk to people is measured in two parameters: 1. The individual risk which is frequency at which a given individual potentially expose

to hazard or harm; 2. The societal risk which is the frequency of the accident that can potentially consume

multiple casualties; Other risk measures according to field of study are: 1) Major accident : fatality/year or injury ( 1st or 2nd degree, air drum rupture, building burn, collapse etc) 2) Human health : cases (reported), incident (rate cases), fatality, life loss expectancy 3) Financial : money loss (lost), ruin 4) Ecosystem : population of indicator species, lost species; community diversity

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Response of people toward risk generally divided into two: 1) Voluntary risk where the people willing to take the risk which they want such as

smoking and climbing a mountain; 2) Involuntary risk which is out of their control for example flood and contaminated

vegetables with pesticide.

The risk should be tolerable which is the risk should be monitored and balance between cost and benefit. Wherever possible the risk must be reduced to ‘As Low As Reasonably Practicable’ (the ALARP). Public should determine cost benefit study of a project. After all, for securing of benefits, health and safety of environment the society or authority must regulate the laws and policy. Figure 5 illustrates the level of risk and ALARP. Industrial Risk

Malaysia had experience some major accidents typically an explosion and fire of a fire cracker plant, an explosion of a ship-tanker loaded with hydrocarbon and recently a toxic chemical release from a weed killer factory. According to Perkeso’s report, the rank of accidents in manufacturing of chemicals in 1996 are the third largest behind accidents in manufacturing of metals, machines, tools which are the highest followed by accidents in woods manufacturing and furniture (Perkeso, 1996).

Intolerable region Risk cannot be justified on any ground (except in extraordinary circumstances) ------------------------------------------------------------------------------------------ Tolerable region Tolerable region if risk reduction is not reasonable or its cost is not proportional to the improvement gained. ---------------------------------------------------------------------------- Acceptable region Broadly acceptable region

Figure 5. Levels of Risk and ALARP

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A measure is required to determine the performance of facility, site and industry. Generally the criteria are expressed as frequency. They are set as standards of safety performance which may be used to indicate the situations. For Department of Environment Malaysia set the following criteria:

Residential Area and new facility =1x10-6 fatality/person/year Industrial = 1x10-5 fatality/person/year

Published risk criteria for other countries are presented in Table 1. Typical of comparison of Voluntary risk and Involuntary Risk is shown in Table 2:

Table 1: Risk Criteria For Population Risk

Authority Intolerable Risk (per year) Negligible Risk (per year) Netherlands (new plants) 10-6 10-8 EPA, West Australia (new plant)

10-5 10-8

United Kingdoms (new housing)

10-5 10-6

Hong Kong (new plants)

10-5 10-6

NSW Australia (new plants and Housing)

10-6 -

Table 2: Comparison of Voluntary and Involuntary Risks (Kletz,1989 )

Voluntary Individual Risk

Activity Risk of Death Per Person Per Year Smoking (20 cigarettes per day) Football Rock Climbing Car Driving

500x10-5

7.5x10-5

120x10-5

4x10-5

Involuntary Individual Risk

Activity Risk of Death Per Person Per Year Flood (US) Lightning (UK) Storm (US) Leukimia Influenza

500x10-7

1x10-7

8x10-7

800x10-7

6x10-7

Chemical Risk

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Chemical exposure causes health risk. Examples of major event are Love canal Tragedy (1970s), Minamata bay(1932-1968) and Bhopal disaster (1984). Hooker Chemical Company converted uncompleted canal to chemicals dumping Ground. After covered the chemicals with land, the land was sold to Niagara Fall City School Board. The leaking of chemical leaking from site in 1977, many health problems reported. Residents were evacuated.

Started from 1932-1968, Chisso Corporation located in Kumamoto, Japan dumped an estimated 27 tons of mercury compunds into Minamata Bay. Thousands Developed symptons of methyl mercury poisoning. The illness become known as‘Minatama disease’. Methyl isocyanate (MIC) released from a tank of a plant owned by Union Carbide India Limited. 3,800 person died, 40 person permanent total disability, 2,680Persons experienced permanent partial disability. In Malaysia the Use and standards of exposure of Chemicals Hazardous to Health (USECHH), Regulations 2000 spell out the requirements for systematic control of risks of chemicals hazardous to health and requirement to exercise Chemical Health Risk Assessment. The imposed regulations covers all places of work except chemicals defined as radioactive materials, foodstuff, chemical solely explosives or flammables or solely because there are at high or low temperatures or high pressure, and those which are pharmaceutical products. Using the estimates calculated by a risk management as a basis for making decisions is termed risk management. Risk management may be defined as evaluating alternative, actions and selecting among them, entails consideration of political, social, economic and engineering information with risk-related information to develop, analyze and compare regulatory options and to select the appropriate regulatory response to a potential chronic health hazard. The selection process necessarily requires the use of value judgments on such issues as the acceptability of risk and the reasonableness of the costs of control. In the risk assessment, it will provide information to decision makers as to the consequences of possible actions. Important decisions that could use risk estimates include selecting the preventive and treatment options. It should emphasize that risk estimates are only one type of information used, and hazardous chemicals decisions are often driven by management or other factors. Other countries imposed the legislation which related to CHRA are:

Country Legislation Year United State OSHA 1970

U.K. HSW Act,COSHH 1974, 1996

Australia NSW OSHA 1983

Germany Getstoff V 1986

South Korea TCCL 1990

Malaysia USECHH 2000

In Malaysia the Use and standards of Exposure of Chemicals Hazardous to Health (USECHH), Regulations 2000 spell out the requirements for systematic control of risks of chemicals hazardous to health and requirement to exercise chemical Health Risk Assessment. The imposed regulations covers all places of work except chemicals defined

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as radioactive materials, foodstuff, chemical solely explosives or flammables or solely because there are at high or low temperatures or high pressure, and those which are pharmaceutical products. Under the Use and Standard of Exposure of Chemicals hazardous to Health) Regulation 2000 or USECHH Regulation 2000, the duty to perform an assessment of health risk arising from the use of chemicals hazardous to health at the place of work is mandatory whereby employers are not permitted to use any chemicals hazardous to health unless an assessment has been conducted. The main objective is enable decisions to be made on appropriate control measures, induction and training of employees, monitoring and health surveillance activities as may be required to protect. Other objectives are:

- To evaluate the degree of exposure of employees to the chemicals hazardous to health, either through inhalation, skin absorption or ingestion

- To identify the hazards posed by each chemical substance used, stored, handle or transported within the work place

- To evaluate the adequacy of existing control measures - To conclude of the significance of the health risk posed by the chemicals

hazardous to health, and - To recommend further appropriate control measures to prevent or reduce risks.

Using the estimates calculated by a risk management as a basis for making decisions is termed risk management. Risk management may be defined as evaluating alternative, actions and selecting among them, entails consideration of political, social, economic and engineering information with risk-related information to develop, analyze and compare regulatory options and to select the appropriate regulatory response to a potential chronic health hazard. The selection process necessarily requires the use of value judgments on such issues as the acceptability of risk and the reasonableness of the costs of control. In the risk assessment, it will provide information to decision makers as to the consequences of possible actions. Important decisions that could use risk estimates include selecting the preventive and treatment options. It should emphasized that risk Here the risk assessment process is divided into two based on the risk criteria above: Industrial Risk

For industrial risk assessment the process is illustrated as depicted in Figure 6:

Hazards Identification

Determination of Failure Rate

Hazard Zone Analysis

Industrial Risk Quantification

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Figure 6. Overview of Risk Analysis Process Hazards Identification

The potential hazards that are associated with an industrial facility or installation is function of the materials being processed, processing systems, and procedures used for operating and maintaining the facilities, and hazard detection and mitigation systems provided. HAZOP or/and checklist methods are proposed to be used for the hazard identification of the facilities. Determination of Failure Rates

The potential accidents that can occur at a facility and the resulting release sources of hazardous fluids are determined from a combination of past history of release from similar installations or facilities and their specific information. This step in the analysis defines the potential release source and the conditions of release for each failure case. The frequency with which a given failure case is expected to occur can be estimated by using a combination of:

1) Historical experience. 2) Failure rate data on similar types of equipment 3) Service factors, and 4) Engineering judgment.

For single component of failures (e.g. pipe rupture), failure frequencies will be obtained from published industrial failure rate databases. For multiple component failures (e.g., failure of an automatic system for preventing tank overfill), Fault Tree Analysis (FTA) techniques will be used. Hazard Zones Analysis For each defined failure case, the release sources, rates and conditions will be analysed using the best available hazard quantification techniques to produce a set of hazard zones. Physical and thermodynamic data and models for producing hazard profiles for the fire, explosion and toxic release are sought from technical publications. Models are used to quantify of the hazards which cover: 1) Release rates and conditions 2) Ambient weather conditions (wind speed, air temperature, humidity, and atmospheric

stability). 3) Effects of local blocks and terrains (tall building, diking, vegetation). 4) Identification, description and estimation selected response technologies for example

of an accident that causes marine oil spill clean up, related to given environmental

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conditions, changes in oil characteristics and operational considerations in the affected area.

Industrial Risk Quantification The results in the forms of time varying hazard zones combined with the probabilities of occurrence in the zones, site specific weather conditions, local terrain, population data, and ignition source data to determine the expected number of casualties for each specific failure case, assuming that each failure case occurs. The expected casualties for each case can be combined with the annual probability of occurrence for each case to produce the following risk indicators.

1) F-N curves. 2) Risk contours. 3) Average annual individual risk.

Risk Assessment The risk contours and average annual individual f risk of the industrial facility or installation area will be investigated. The effectiveness of current mitigation system, especially for the off-site emergency response plan will be evaluated. Since any potential major accident will threaten nearby community, the risk result will be compared with risks from other human activities to indicate the level of risk and judging the acceptability of the risk associated with the port facilities. Risk Management Results from the risk assessment will support the decision making for risk reduction measures of the current area and the new proposed area facilities. The result will be presented in risk control effectiveness (expected reduction of risk) and cost effectiveness (based on current market value of land and the facilities). In addition, a study of surrounding and realineation is proposed to analyse the benefit of sifting the current facilities to a new area. Chemical Risk Steps to conduct Chemical risk assessment as follows: Firstly to decide ‘assessor’ (leader) and team for assessment . Assessor is assisted by one or more of the following team members : The company’s safety and health officer or safety engineer The company’s doctor, preferably registered occupational doctor The company’s process/chemical engineer or chemist An experienced and knowledgeable member of the safety and health committee An industrial/occupational health nurse

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Figure 7: Flowchart of Chemical Health Risk Assessment Information to be collected: Chemicals hazardous to health used or released in the workplace Layout plan of work area Process Flowchart Employees at risk Control equipment design parameter and maintenance Accidence and incidence Monitoring record Health surveillance program Training program Personnel protective equipment The process is summarized in form of a flowchart as depicted in Figure 7.

Decide assessor

Gathering Information

Determine Degree of Hazard

Relevant information-such as on nature, degree & Exposure, control measure

Literature/MSDS

Divide Work Unit A group of workers doing similar task i.e. having similar Potential for exposure In one work area

Evaluate Exposure Site visit

Adequacy of Control

Conclusion Adversely affected/not

Identify action

Report Review

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3.2.2. Exposure assessment Exposure involves physical contact with the agent. The three primary routes are ingestion, inhalation and dermal contact. To assess exposure, data on the numbers of people exposed the routes of exposure and the amount, duration and timing of each exposure route must be ascertained. For example, if exposure occurred only during recreational swimming, dermal contact would be the primary route of exposure and the assessment would incorporate this information. The total absorbed dose is a summation of the dose absorbed by each route. 3.2.3. Exposure-response assessment

After a potential hazard has been recognized, its potential for eliciting a response must be examined. The dose-response facet deals with the relationship between the level of exposure and the magnitude of the response. For example, increasing doses of an agent should cause greater adverse effects. If reliable data from humans are available, the quantitation of adverse effects is generally considered more reliable and more easily made. However, as with hazard identification, most dose-response studies are conducted on animals. Data from such studies must be examined critically since most toxic effects are observed after relatively high doses. In addition, animals may have different susceptibilities than humans and strains of experimental animals are less genetically diverse than the populations of humans. On the positive side, it is possible to control experimental variables for animal studies, a situation not possible in human epidemiology studies. Ecological receptors can receive more exposure to contaminants in the environment and can be more sensitive than humans. Protecting against risks to human health will not necessarily protect the environment. People do not interact with their environment in identical ways to those of other organisms, so separate human health and ecological assessments generally are necessary. As an example, consider a hazardous chemical found in a wetland. A fence surrounding the wetland may be perfectly adequate to prevent human access

3.2.4. Risk characterization This facet is an integration and summation of the hazard identification, dose-response data and exposure assessment. The goal is to estimate the possibility or probability that humans, exposed to some concentration of an agent, will be affected by that agent. It is only as reliable as the information generated by each phase in the evolution of the risk characterization. Its adequacy is determined by enumeration of both the strengths and weaknesses of each part of the qualitative and quantitative assessment. 4. COMPARATIVE RISK ASSESSMENT In the past, the decision making process concerning the location and safety of proposed development and on various land uses relied almost entirely on technical engineering standards, codes and associated safety controls. The approach was based on the belief that such legislations, procedures or systems of management and engineering

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safety controls can adequately cope with all hazards. However, it is not true even though the industries or installations are designed and operated properly. Accidents can not be eliminated totally. Thus, it needs planning aspects on the preservation of natural environment and monument allocation and the future industrial land uses. The location of hazardous installation may not be of concern to public. In fact, existence industries either owners or their employees may want to maintain the status quo. Industries which might be expanded up to the border of their neighbours are responsible to risk or impact of the operation on those neighbours (based on safety and environmental consideration). Segregation is inherently a safe solution for locating the hazardous installations in an area. The tendency of an industrial decay, the boredom of employees and other issues will affect its neighbours. This requires fundamental recognition of the technological and economic constraints and limitations of engineering control to decide. As a result, tools such as quantitative risk assessment were developed, initially to address issues of technical nature. A zero risk is impossible to achieve. Thus, the important task or useful task is to determine acceptability of the risk of a new proposed area. One approach or currently practice is to compare risk level with sets of standard of risks or other risks that people and the regulatory can accept them either the risks are voluntary or involuntary risks. The Department of Environment of Malaysia and the Department of Occupational Safety and Health Malaysia had set the acceptable values as mentioned earlier. The risk 1x10-6 fatality/person/year is generally acceptable for both departments. 5. SUMMARY

The ecological risk assessment (ERA) has been discussed. It has been applied widely in variety of industries such as agricultural, chemical, process and petroleum industries and other sectors environmental management of effluent discharge, finance, health and medicine, ecotoxicology, military and aerospace operation, natural disaster, transport and industrial safety sectors . It initially used to assess the health impact to human but latter to assess the environmental impact products. In Malaysia the risk assessment is a prerequisite in Environmental Impact Assessment (EIA), Safety Report under the Occupational Safety and Health (Control of Industrial Major Accident Hazards) regulations or CIMAH regulations, 1996 and the Occupational Safety and Health (Chemical Health Risk Assessment) regulations 2000 to evaluate risk of chemical exposure. Generally the risk assessment process involves hazard identification, failure rate or frequency of exposure, consequence analysis, risk determination and ranking and risk management or identifies response. Acceptability of the risks is determined based on sets of standards and other risks that acceptable by people or the regulatories.

6. CONCLUSION The environmental risk assessment is means to reduce health impact to human being which has been applied in various industries. It is systematic procedures to assess the risk for new industry or facility (installation) for example in EIA and also to assess the risk for development of the existing industry or facility as required by CIMAH . The acceptability of risks depends on the sets of standards stated by the legislations or other risks which agreed by people or the regulatories. The result from risk assessment is

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important for managing the hazard posed by the industry or facility as well as to comply with the legislations.

7. REFERENCES Ball D. J. , Environmental risk assessment and the intrusion of bias, Environment

International , 28( 2002), 592-544. Bridges J. Human Health and environmental risk assessment: the need for more

Harmonized and Integrated approach, Chemsphere (52), 1347-1351. Commission Directive 93/67/EEC of 20 July 1993 laying down the principles for

assessment to man and the environment of substances notified in accordance with Council directive 67/548/EEC. Off. J. Eur. Communication, I.227,9-18., 8 September 1993.

Department of Planning(1999)., Environmental Risk Impact Assessment Guidelines, Hazardous Industry Planning Advisory No.3.

EPA (1991), Risk Assessment Guidance for Superfund, vol.1, Human Health Evaluation manual, Human Protection Agency, Office of Emergency and Remedial response, Washington.

Furlong J., EC approach to environmental risk assessment of new substance,The Science of the Total Environment, 171(1995) pp275-279.

Griffiths R(2002)., Risk Assessment, management and uncertainty, Encyclopedia of Environment, Edicted by Abdel H. El-Shaarawi and Walter W. Piegorsch, John Wiley & Sons, Ltd, Vol.3 pp1812-1833,.

Karman C.C(2000)., The role of time in environment risk assessment, Research, Spill Science and technology Bulltetin, Vol. 6, No.2, pp 159-164,.

Kletz, T.Hydrocarbon Processing, Vol. 56 No.5, May77,pp297,. Mark Middleton, Using Risk Matrix, tce, September 2001, pp34-37, OSECH (2000) (Use and Standards of Exposure of Chemicals Hazardous to Health)

Regulations. Perkeso(1996):lapuran Tahunan 1996. Kuala Lumpur, 58-69, 1996. Phare(2001)., Project: Planning for emergencies involving dangerous substances for

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