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.

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.

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 scientific basis, inference assumptions, regulatory uses, and research needs in risk assessment are considered in this two-part volume. The first part, Use of Maximum Tolerated Dose in Animal Bioassays for Carcinogenicity, focuses on whether the maximum tolerated dose should continue to be used in carcinogenesis bioassays. The committee considers several options for modifying current bioassay procedures. The second part, Two-Stage Models of Carcinogenesis, stems from efforts to identify improved means of cancer risk assessment that have resulted in the development of a mathematical dose-response model based on a paradigm for the biologic phenomena thought to be associated with carcinogenesis.

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

This completely updated edition of Exposure Assessment in Environmental Epidemiology offers a practical introduction to exposure assessment methodologies in environmental epidemiologic studies. In addition to methods for traditional methods -- questionnaires, biomonitoring -- this new edition is expanded to include geographic information systems, modeling, personal sensoring, remote sensing, and OMICs technologies. In addition, each of these methods is contextualized within a recent epidemiology study, maximizing illustration for students and those new to these to these techniques. With clear writing and extensive illustration, this book will be useful to anyone interested in exposure assessment, regardless of background.