Integrated Risk Assessment — Results from an International Workshop

The World Health Organization's International Programme on Chemical Safety and international partners have developed a framework for integrated assessment of human health and ecological risks and four case studies. An international workshop was convened to consider how ecological and health risk assessments might be integrated, the benefits of and obstacles to integration, and the research and mechanisms needed to facilitate implementation of integrated risk assessment. Using the case studies, workshop participants identified a number of opportunities to integrate the assessment process. Improved assessment quality, efficiency, and predictive capability were considered to be principal benefits of integration. Obstacles to acceptance and implementation of integrated risk assessment included the disciplinary and organizational barriers between ecological and health disciplines. A variety of mechanisms were offered to overcome these obstacles. Research recommendations included harmonization of exposure characterization and surveillance methods and models, development of common risk endpoints across taxa, improved understanding of mechanisms of effect at multiple scales of biological organization, and development of methods to facilitate comparison of risks among endpoints.     

美国、加拿大环境和健康风险管理方法

对目前美国和加拿大多个部门使用的风险评价与风险管理方法进行了全面回顾和综合分析,论述各种不同方法的特征,深入探讨各种管理方法的基础、利弊、使用经验,辨识环境、人类健康和职业健康风险综合方法中应该包含的要素,阐述风险管理目标的确定方法,以期为中国的环境风险管理提供经验。     

Abuse of hypothesis testing statistics in ecological risk assessment

Statistical hypothesis testing is commonly used inappropriately to analyze data, determine causality, and make decisions about significance in ecological risk assessment. Hypothesis testing is conceptually inappropriate in that it is designed to test scientific hypotheses rather than to estimate risks. It is inappropriate for analysis of field studies because it requires replication and random assignment of treatments. It discourages good toxicity testing and field studies, it provides less protection to ecosystems or their components that are difficult to sample or replicate, and it provides less protection when more treatments or responses are used. It provides a poor basis for decision‐making because it does not generate a conclusion of no effect, it does not indicate the nature or magnitude of effects, it does not address effects at untested exposure levels, and it confounds effects and uncertainty. Attempts to make hypothesis testing less problematical cannot solve these problems. Rather, risk assessors should focus on analyzing the relationship between exposure and effects, on presenting a clear estimate of expected or observed effects and associated uncertainties, and on providing the information in a manner that is useful to decision‐makers and the public.     

Practical Decision Methods for Watershed Management

Why are formal statistical methods for risk-based decision-making so seldom used in the practice of watershed management? I contend that complex formal methods, while internally consistent, are often inappropriate to real world decision-making. The primary purpose of risk analysis is to support risk management, and decision methods need to be effective not just in evaluating risk, but also in communicating risk among stakeholders and decision makers. Useful methods must be not only correct, but also readily communicable. Many formal risk-based decision methods have real obstacles to practical application in one of the following areas: (1) many important components of risk that matter to stakeholders are difficult to express in quantitative terms, and any method which turns “fuzzy” information and subjective opinion into hard numbers is prone to be regarded with suspicion; (2) methods which are not understandable and convincing to decision makers have little practical value; (3) a complex formal analysis will be seen as misguided or irrelevant if it does not represent the full spectrum of management goals. This paper compares the process of watershed management with the process of ecological risk assessment, highlighting similarities and key differences. A practical decision method which balances quantitative rigor with ability to communicate to and forge consensus among stakeholders is then outlined with reference to a successful case study.     

Genotoxicity risk assessment: a proposed classification strategy

Recent advances in genetic toxicity (mutagenicity) testing methods and in approaches to performing risk assessment are prompting a renewed effort to harmonize genotoxicity risk assessment across the world. The US Environmental Protection Agency (EPA) first published Guidelines for Mutagenicity Risk Assessment in 1986 that focused mainly on transmissible germ cell genetic risk. Somatic cell genetic risk has also been a risk consideration, usually in support of carcinogenicity assessments. EPA and other international regulatory bodies have published mutagenicity testing requirements for agents (pesticides, pharmaceuticals, etc.) to generate data for use in genotoxicity risk assessments. The scheme that follows provides a proposed harmonization approach in which genotoxicity assessments are fully developed within the risk assessment paradigm used by EPA, and sets out a process that integrates newer thinking in testing battery design with the risk assessment process. A classification strategy for agents based on inherent genotoxicity, dose-responses observed in the data, and an exposure analysis is proposed. The classification leads to an initial level of concern for genotoxic risk to humans. A total risk characterization is performed using all relevant toxicity data and a comprehensive exposure evaluation in association with the genotoxicity data. The result of this characterization is ultimately used to generate a final level of concern for genotoxic risk to humans. The final level of concern and characterized genotoxicity risk assessment are communicated to decision makers for possible regulatory action(s) and to the public.     

Hierarchical Activity Model for Risk‐Based Decision Making

For the practical implementation of the assessment of environmental impact, actual procedures and data requirements should be clarified so that industrial decision makers understand them. Researchers should consider local risks related to processes and environmental impact throughout the life cycle of products simultaneously to supervise these adverse effects appropriately. Life cycle assessment (LCA) is a useful tool for quantifying the potential impact associated with a product life cycle. Risk assessment (RA) is a widely used tool for identifying chemical risks in a specific situation. In this study, we integrate LCA and RA for risk‐based decision making by devising a hierarchical activity model using the type‐zero method of integrated definition language (IDEF0). The IDEF0 activity modeling language has been applied to connect activities with information flows. Process generation, evaluation, and decision making are logically defined and visualized in the activity model with the required information. The activities, information flows, and their acquisitions are revealed, with a focus on which data should be collected by on‐site engineers. A case study is conducted on designing a metal cleaning process reducing chemical risks due to the use of a cleansing agent. LCA and RA are executed and applied effectively on the basis of integrated objective settings and interpretation. The proposed activity model can be used as a foundation to incorporate such assessments into actual business models.     

Precautionary Health Risk Assessment: Case Study of Biological Insecticides

In conventional risk assessment approaches, experts define the scientific questions that can legitimately be asked and the burden of proof is on the potentially exposed community to show that a proposal is unsafe. Here I propose an alternative approach, precautionary health risk assessment, in which the scientific questions to be addressed are defined by community consultation. I illustrate the approach with a case study of exposure to biological insecticides. This illustrates how community consultation can have a critical influence on the outcome of a health risk assessment. Government agencies may be reluctant to involve stakeholders in health risk assessments because this involves a loss of political control of the process. However, precautionary approaches are likely to lead to better health outcomes where decision stakes and scientific uncertainty are both high.     

Risk Communication and the Precautionary Principle

The perception of risks for environment and health deriving from globalization processes and an uncontrolled use of modern technologies is growing everywhere. The greater the capacity of controlling living conditions, the larger is the possibility of misusing this power. In environmental and occupational health research we tend to reduce the complexity of the observed phenomena in order to facilitate conclusions. In social and political sciences complexity is an essential element of the context, which needs to be continuously considered. The Precautionary Principle is a tool for facing complexity and uncertainty in health risk management. This paper is aimed at demonstrating that this is not only a problem of technical risk assessment. Great attention should also be paid to improve risk communication. Communication between the stakeholders (experts, decision makers, political and social leaders, media, groups of interest and people involved) is possibly the best condition to be successful in health risk management. Nevertheless, this process usually runs up against severe obstacles. These are not only caused by existing conflicts of interest. Differences in values, languages, perceptions, resources to have access to information, and to express one's own point of view are other key aspects.     

ENVIRONMENTAL RISK ASSESSMENT: TASKS AND OBLIGATIONS

Synthesizing, characterizing, and communicating the risk science information used in environmental decision-making depends in the first instance on the nature and quality of the technical analysis. At the same time, other important features of the risk analysis, features that require special attention to provide context for the analysis as a whole, are frequently overlooked in practice or in presentation. Now, as the field expands to meet new challenges and to include new participants, all practitioners — government, academics, industry, and interest groups — must give renewed emphasis to certain hall marks of sound risk assessment: identifying incomplete information and its influence on the risk assessment process, articulating alternative assumptions and the scientific or policy reasons for choices made among alternatives, describing process considerations and limitations as well as numerical results, and fully informing decision makers, the press, and the interested public. The resulting greater clarity and transparency in the scientific analyses that under lie environmental decision making can enhance credibility and public confidence in the scientific foundation for those decisions.     

Strategies for Assessing Cumulative Ecological Risks

Assessing and managing the ecological risks from multiple stressors is becoming increasingly important as our environmental and regulatory focus moves from managing point sources to one of managing and trading risks from multiples sources over large geographic areas. There are important corollaries to this shift in focus and scale, one is the increased role and importance of non-chemical stressors in shaping and controlling ecological systems, the fact that these categories of stress are, for the most part, not regulated under the traditional legislative mandates, that we have limited knowledge regarding the interaction of chemical and non-chemical stressors, that at large scales we are faced with the integration of and trading of risks to multiple resource categories. This trend of increased attention to regional-scale environmental issues requires the development of new analysis and interpretive strategies and highlight the need for a systematic framework for addressing the ecological effects of multiple stressors at regional ecological scales. We propose that such a framework have three essential properties: it be risk-based; it be effects driven; and it have the flexibility to be used in both a retrospective and prospective manner. While several approaches have been proposed we believe that an ecological risk assessment framework satisfies these criteria, has been used successfully in regional assessments, and can readily be modified and adapted to serve a wide variety of problem settings.     

Approaches for Integrated Risk Assessment

Recognizing the need to enhance the effectiveness and efficiency of risk assessments globally, the World Health Organization's International Programme on Chemical Safety, the U.S. Environmental Protection Agency, the European Commission, and the Organization for Economic Cooperation and Development developed a collaborative partnership to foster integration of assessment approaches used to evaluate human health and ecological risks. The objectives of this effort included: improving understanding of the benefits of integration, identifying obstacles to the integration process, and engaging key agencies, organizations, and scientific societies to promote integration. A framework with supporting documentation was developed to describe an approach for integration. Four case studies were constructed to illustrate how integrated risk assessments might be conducted for chemical and nonchemical stressors. The concepts and approaches developed in the project were evaluated in an international workshop. The goal of this effort was international acceptance of guidance for integrated risk assessment.     

Lessons From Risk Assessment

Risk assessment and uncertainty analysis are important tools for improving environmental decision making. However, their value is limited when the environmental endpoints assessed by scientists do not coincide with the publicly-meaningful attributes that are of concern to decision makers. Approaches for addressing this disconnect are presented using examples from water quality assessment and management. Recommendations to scientists for maximizing the usefulness of uncertainty analysis are given.     

From Assessment to Policy: Lessons Learned from the U.S. National Assessment

The process of translating scientific information into timely and useful insights that inform policy and resource management decisions, despite the existence of uncertainties, is a difficult and challenging task. Policy-focused assessment is one approach to achieving this end. It is an ongoing process that engages both researchers and end-users to analyze, evaluate and interpret information from multiple disciplines to draw conclusions that are timely and useful for decision makers. This paper discusses key characteristics of a policy-focused assessment process, including (1) ongoing collaboration between the research, assessment, and stakeholder communities; (2) a focus on stakeholder information needs; (3) multidisciplinary approaches; (4) use of scenarios to deal with uncertainties; and (5) evaluation of risk management options. We illustrate the particular challenge to assessors of providing the specific types of insights stakeholders need to effectively influence policy decisions. And we discuss the role that assessment can play in formulating an agenda for future research. Examples from the U.S. National Assessment of “The Potential Consequences of Climate Variability and Change for the United States” are used to illustrate a policy-focused assessment process. For many of the participants, the first U.S. National Assessment was an extraordinary learning experience about how to develop better ways of conducting assessments.     

A risk assessment approach for fresh fruits

Aims:  To describe the approach used in conducting a fit‐for‐purpose risk assessment of microbiological human pathogens associated with fresh fruit and the risk management recommendations made. Methods and Results:  A qualitative risk assessment for microbiological hazards in fresh fruit was carried out based on the Codex Alimentarius (Codex) framework, modified to consider multiple hazards and all fresh (whole) fruits. The assessment determines 14 significant bacterial, viral, protozoal and nematodal hazards associated with fresh produce, assesses the probable level of exposure from fresh fruit, concludes on the risk from each hazard, and considers and recommends risk management actions. A review of potential risk management options allowed the comparison of effectiveness with the potential exposure to each hazard. Conclusions:  Washing to a recommended protocol is an appropriate risk management action for the vast majority of consumption events, particularly when good agricultural and hygienic practices are followed and with the addition of refrigerated storage for low acid fruit. Additional safeguards are recommended for aggregate fruits with respect to the risk from protozoa. Significance and Impact of the Study:  The potentially complex process of assessing the risks of multiple hazards in multiple but similar commodities can be simplified in a qualitative assessment approach that employs the Codex methodology.     

Assessing Risks of Plant-Based Pharmaceuticals: I. Human Dietary Exposure

Protein-based drugs are the fastest growing class of drugs for the treatment of disease in humans and other animals. However, the current method of producing proteins for pharmaceutical application is predicted to fall short because of population growth and demographic trends. This study characterized human dietary risks using quantitative risk assessment techniques for three pharmaceutical proteins produced in field-grown maize. The three proteins were aprotinin, gastric lipase, and Escherichia coli heat-labile enterotoxin B subunit (LT-B). The human dietary risks from the three proteins inadvertently occurring in food were evaluated using three different exposure scenarios so that potential risks could be compared. The three exposure scenarios ranged in conservatism to evaluate the range of risk between the proteins and scenarios. Risk quotients (RQs) were calculated for all three scenarios to integrate exposure and effect (toxicity). The risk assessments revealed that the most conservative scenario produced higher RQs than the other two scenarios. The dietary risks from scenario 1 for aprotinin were three orders of magnitude greater than for scenario 2, and four orders of magnitude greater than for scenario 3. This risk assessment revealed that dietary risks will vary dramatically and depend on factors such as the specific pharmaceutical protein, protein expression, and exposure scenarios. The assessment also reinforced the need for case-by-case assessments.     

The Health Risk Assessment Approach,a Tool for Managing Risks on the Scale of a Territory: A French Experience

In France, regulatory analysis of the environment and human health potential consequences is implemented for an isolated industrial activity that requests an authorization to operate using the health risk assessment method. To date, the question is enlarged to the impact of the combination of multiple sources of pollution on the same territory. The main conclusions of the work launched by the French High Council of Public Health focus on four key points: (i) the utility of conducting such an analysis at a territory scale, (ii) the delimitation of the area, (iii) the conditions for the different stakeholders’ involvement, and (iv) the methodological specificities of the “zone health risk assessment.” The work encompassed literature reviews, seminars, and interviews of stakeholders. The utility of a Z-HRA is the central objective for the management of risk. It can no longer be conducted only for itself. The delimitation of the zone entails economic, political, environmental, and population aspects. Stakeholders become key actors in a steering and monitoring committee. Among methodological specificities, cumulative exposure comes first. Interpretation of the results should focus on risk management objectives. Finally, inclusion of Z-HRAs in flexible regulations that can be adapted to the local context is recommended.     

Implementing Hormetic Effects in the Risk Assessment Process: Differentiating Beneficial and Adverse Hormetic Effects in the RfD Derivation Process

Hormetic effects have been purported to be both beneficial and adverse. The decision of whether an effect is adverse or beneficial can have important implications for public health and risk assessment. A functional approach is proposed for determining the types of responses available for the incorporation of hormesis in the RfD process. These response categories include: (1) beneficial; (2) adverse; and (3) either beneficial or adverse depending on specific circumstances. Examples of endpoints in each category are presented and discussed. Other issues affecting the RfD process include: (1) the integration of multiple hormetic responses; (2) the importance of endpoint selection in determining the type of hormetic response; and (3) the assumption of hormesis when responses are unobservable due to low background response in controls.     

The Health Risk Assessment Performed in California for the Herbicide Simazine: A Case Study

Simazine, a member of the triazine group, is registered in California for weed control in soils where a wide range of crops will be (or are) planted. The health risks from simazine use in California were recently assessed by the California Department of Pesticide Regulation (CDPR) for all potential (acute and long-term) exposure scenarios relevant to Californian residents and workers. The results of the CDPR risk assessment indicate that current exposure levels in many of the scenarios under consideration are not health protective for the people in California. The main objective of the present summary report (i.e., case study) was two-fold, both for offering a forum to advance further scientific discussion: (1) to highlight the toxicity and exposure data as well as the assumptions used in the CDPR simazine risk assessment and then (2) to systematically requalify the uncertainties and complexities involved in terms of the toxicity and exposure appraisals given in that risk assessment. In both attempts, the focus was more on residential exposures for young children and women of child-bearing age in that simazine was reportedly seen to exhibit neuroendocrine effects across a variety of species.     

Trends in the Development of Ecological Risk Assessment and Management Frameworks

Ecological risk assessment and management have grown from a long history of assessment and management activities aimed at improving the everyday lives of humans. The background against which ecological risk assessment and management has developed is discussed and recent trends in the development of risk assessment and management frameworks documented. Seven frameworks from five different countries are examined. All maintain an important role for science, suggest adaptive approaches to decision-making and have well-defined analytical steps. Differences in approaches toward the separation of policy and science, the preference for management over assessment, the inclusion of stakeholders, the iterative nature of the analytical cycle, the use of decision criteria and economic information suggest considerable evolution in framework design over time. Despite the changes, no consensus on the design of a framework is apparent and work remains to be done on refining an integrative framework that effectively incorporates both policy and science considerations for environmental management purposes.     

Plan for an Integrated Human and Environmental Risk Assessment in the S. Domingos Mine Area (Portugal)

The need for the integration of the assessment of human and ecological risks in contaminated areas, such as derelict mines, widely increases. The risk assessment process is becoming a powerful tool to provide sound scientific bases for decision-making processes. In Portugal, the risk assessment process is in its early years and the lack of multidisciplinary teams of experts is frequently mentioned as the main obstacle to its implementation. Therefore, the majority of the reclamation actions are based on impact assessment studies that usually are characterized by few biological and toxicological considerations. In order to account for some of these constraints, the ecological risk assessment framework proposed by the U.S. Environmental Protection Agency was used to plan the assessment of human and ecological risks posed by the high concentrations of metals scattered in the vicinity of S. Domingos mine, a cuprous pyrite mine located in the Southeast Alentejo (Portugal). This study presents the problem formulation phase of the assessment. It includes all the scientific information available for the area, a conceptual model, and an analysis plan for the risk assessment process. Following a tiered approach, several tasks were planned in order to acquire chemical, toxicological, and ecological information, in order to compensate for the lack of toxicity data for site-specific species.