This document presents an analysis of the Environmental Protection Agency's (EPA) general risk assessment practices, based on typical historic & current practice. Chapters: Introduction to EPA Risk Assessment; EPA Risk Assessment & Public & Environmental Health Protection; Uncertainty & Variability; Considering Information Gaps in Health Assessments: Use of Default & Extrapolation Assumptions; Site- & Chemical-Specific Assessments; Ecological Assessment; Summary & Recommendations; List of Useful Abbreviations & Acronyms; General References; References of EPA Risk Assessment Guidelines; & Additional Useful Web Sites. Illustrations.

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 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.

Recently, environmental scientists have been required to perform a new type of assessment-ecological risk assessment. This is the first book that explains how to perform ecological risk assessments and gives assessors access to the full range of useful data, models, and conceptual approaches they need to perform an accurate assessment. It explains how ecological risk assessment relates to more familiar types of assessments. It also shows how to organize and conduct an ecological risk assessment, including defining the source, selecting endpoints, describing the relevant features of the receiving environment, estimating exposure, estimating effects, characterizing the risks, and interacting with the risk manager. Specific technical topics include finding and selecting toxicity data; statistical and mathematical models of effects on organisms, populations, and ecosystems; estimation of chemical fate parameters; modeling of chemical transport and fate; estimation of chemical uptake by organisms; and estimation, propagation, and presentation of uncertainty. Ecological Risk Assessment also covers conventional risk assessments, risk assessments for existing contamination, large scale problems, exotic organisms, and risk assessments based on environmental monitoring. Environmental assessors at regulatory agencies, consulting firms, industry, and government labs need this book for its approaches and methods for ecological risk assessment. Professors in ecology and other environmental sciences will find the book's practical preparation useful for classroom instruction. Environmental toxicologists and chemists will appreciate the discussion of the utility for risk assessment of particular toxicity tests and chemical determinations.

Sustainability is based on a simple and long-recognized factual premise: Everything that humans require for their survival and well-being depends, directly or indirectly, on the natural environment. The environment provides the air we breathe, the water we drink, and the food we eat. Recognizing the importance of sustainability to its work, the U.S. Environmental Protection Agency (EPA) has been working to create programs and applications in a variety of areas to better incorporate sustainability into decision-making at the agency. To further strengthen the scientific basis for sustainability as it applies to human health and environmental protection, the EPA asked the National Research Council (NRC) to provide a framework for incorporating sustainability into the EPA's principles and decision-making. This framework, Sustainability and the U.S. EPA, provides recommendations for a sustainability approach that both incorporates and goes beyond an approach based on assessing and managing the risks posed by pollutants that has largely shaped environmental policy since the 1980s. Although risk-based methods have led to many successes and remain important tools, the report concludes that they are not adequate to address many of the complex problems that put current and future generations at risk, such as depletion of natural resources, climate change, and loss of biodiversity. Moreover, sophisticated tools are increasingly available to address cross-cutting, complex, and challenging issues that go beyond risk management. The report recommends that EPA formally adopt as its sustainability paradigm the widely used "three pillars" approach, which means considering the environmental, social, and economic impacts of an action or decision. Health should be expressly included in the "social" pillar. EPA should also articulate its vision for sustainability and develop a set of sustainability principles that would underlie all agency policies and programs.