Uncertainty And Data Quality In Exposure Assessment

Assessment of human exposure to chemicals is a critical input to risk assessment and ultimately to decisions about control of chemicals. This two-part publication aims to improve the quality of information available to decision-makers and its communication. Part one sets out ten principles for characterizing and communicating uncertainty in exposure assessment. A tiered approach to the evaluation of uncertainties using both qualitative (simple) and quantitative (more complex) methods is described. Different sources of uncertainty are identified and guidance is provided on selecting the appropriate approach to uncertainty analysis as dictated by the objectives of the assessment and information needs of decision-makers and stakeholders. Part two addresses the quality of data used in exposure assessment and sets out four basic hallmarks of data quality - appropriateness accuracy integrity and transparency. These hallmarks provides a common vocabulary and set of qualitative criteria for use in the design evaluation and use of exposure assessments to support decisions. This publication is intended exposure assessors risk assessors and decision-makers.

The public depends on competent risk assessment from the federal government and the scientific community to grapple with the threat of pollution. When risk reports turn out to be overblownâ€"or when risks are overlookedâ€"public skepticism abounds. This comprehensive and readable book explores how the U.S. Environmental Protection Agency (EPA) can improve its risk assessment practices, with a focus on implementation of the 1990 Clean Air Act Amendments. With a wealth of detailed information, pertinent examples, and revealing analysis, the volume explores the "default option" and other basic concepts. It offers two views of EPA operations: The first examines how EPA currently assesses exposure to hazardous air pollutants, evaluates the toxicity of a substance, and characterizes the risk to the public. The second, more holistic, view explores how EPA can improve in several critical areas of risk assessment by focusing on cross-cutting themes and incorporating more scientific judgment. This comprehensive volume will be important to the EPA and other agencies, risk managers, environmental advocates, scientists, faculty, students, and concerned individuals.

Risk assessment has become a dominant public policy tool for making choices, based on limited resources, to protect public health and the environment. It has been instrumental to the mission of the U.S. Environmental Protection Agency (EPA) as well as other federal agencies in evaluating public health concerns, informing regulatory and technological decisions, prioritizing research needs and funding, and in developing approaches for cost-benefit analysis. However, risk assessment is at a crossroads. Despite advances in the field, risk assessment faces a number of significant challenges including lengthy delays in making complex decisions; lack of data leading to significant uncertainty in risk assessments; and many chemicals in the marketplace that have not been evaluated and emerging agents requiring assessment. Science and Decisions makes practical scientific and technical recommendations to address these challenges. This book is a complement to the widely used 1983 National Academies book, Risk Assessment in the Federal Government (also known as the Red Book). The earlier book established a framework for the concepts and conduct of risk assessment that has been adopted by numerous expert committees, regulatory agencies, and public health institutions. The new book embeds these concepts within a broader framework for risk-based decision-making. Together, these are essential references for those working in the regulatory and public health fields.

The U.S. Environmental Protection Agency (EPA) is one of several federal agencies responsible for protecting Americans against significant risks to human health and the environment. As part of that mission, EPA estimates the nature, magnitude, and likelihood of risks to human health and the environment; identifies the potential regulatory actions that will mitigate those risks and protect public health1 and the environment; and uses that information to decide on appropriate regulatory action. Uncertainties, both qualitative and quantitative, in the data and analyses on which these decisions are based enter into the process at each step. As a result, the informed identification and use of the uncertainties inherent in the process is an essential feature of environmental decision making. EPA requested that the Institute of Medicine (IOM) convene a committee to provide guidance to its decision makers and their partners in states and localities on approaches to managing risk in different contexts when uncertainty is present. It also sought guidance on how information on uncertainty should be presented to help risk managers make sound decisions and to increase transparency in its communications with the public about those decisions. Given that its charge is not limited to human health risk assessment and includes broad questions about managing risks and decision making, in this report the committee examines the analysis of uncertainty in those other areas in addition to human health risks. Environmental Decisions in the Face of Uncertainty explains the statement of task and summarizes the findings of the committee.

This book closes a current gap by providing the scientific basis for consumer exposure assessment in the context of regulatory risk assessment. Risk is defined as the likelihood of an event occurring and the severity of its effects. The margin between the dose that leads to toxic effects and the actual dose of a chemical is identified by estimating population exposure. The objective of this book is to provide an introduction into the scientific principles of consumer exposure assessment, and to describe the methods used to estimate doses of chemicals, the statistics applied and computer tools needed. This is presented through the backgrounds of the special fields in exposure analysis, such as exposure via food and by the use of consumer products, toys, clothing and other items. As a general concept, human exposure is also understood to include exposure via the environment and from the work setting. In this context, the specific features of consumer exposure are pointed out and put into the context of regulation, in particular food safety, chemicals safety (REACh) and consumer product safety. The book is structured into three parts: The first part deals with the general concepts of consumer exposure as part of the overall risk analysis framework of risk characterization, risk assessment and risk communication. It describes the three basic features of exposure assessment (i) the exposure scenario (ii) the exposure model and (iii) the exposure parameters, addressing external and internal exposure. Also, the statistical presentation of data to characterize populations, in connection with variability, uncertainty and quality of information and the presentation of exposure evaluation results is described. The second part deals with the specific issues of exposure assessment, exposure via food consumption, exposure from use of consumer products, household products, toys, cosmetic products, textiles, pesticides and others. This part also covers methods for acquisition of data for exposure estimations, including the relevant information from regulations needed to perform an accurate exposure assessment. The third part portrays a prospect for further needs in the development and improvement of consumer exposure assessment, as well as international activities and descriptions of the work of institutions that are involved in exposure assessment on the regulatory and scientific level. And conversely, it creates the rationale for the exposure assessment details necessary to satisfy regulatory needs such as derivation of upper limits and risk management issues.

In this text, experts provide a complete sourcebook on methods for addressing variability and uncertainty in exposure analysis.

The regulation of potentially hazardous substances has become a controversial issue. This volume evaluates past efforts to develop and use risk assessment guidelines, reviews the experience of regulatory agencies with different administrative arrangements for risk assessment, and evaluates various proposals to modify procedures. The book's conclusions and recommendations can be applied across the entire field of environmental health.

Incineration has been used widely for waste disposal, including household, hazardous, and medical wasteâ€"but there is increasing public concern over the benefits of combusting the waste versus the health risk from pollutants emitted during combustion. Waste Incineration and Public Health informs the emerging debate with the most up-to-date information available on incineration, pollution, and human healthâ€"along with expert conclusions and recommendations for further research and improvement of such areas as risk communication. The committee provides details on: Processes involved in incineration and how contaminants are released. Environmental dynamics of contaminants and routes of human exposure. Tools and approaches for assessing possible human health effects. Scientific concerns pertinent to future regulatory actions. The book also examines some of the social, psychological, and economic factors that affect the communities where incineration takes place and addresses the problem of uncertainty and variation in predicting the health effects of incineration processes.