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.

Managing environmental contamination requires decision makers to weigh eXlstmg risks against the potential effects of implementing environmental policies - considering both the benefits and disruptions that may result from different actions. The NATO Advanced Research Workshop in Lisbon was an important step in the development and application of cost efficient methods of risk assessment especiaIly within the constraints of a budget. The goal of the workshop was to evaluate the potential for risk assessment to serve as a unified and unifying technique in addressing a wide range of environmental problems. Papers presented in this book discuss issues ranging from specific and local studies (specific site, ecosystem, pollutant) to global decision and management frameworks (watersheds, regions, integration of multiple poIlutants and stressors); they develop a range of approaches starting from specific methods to widely applied public policies (Figure 1). The papers show that the use of risk assessment can provide the scientific basis for environmentaIly sound and cost-efficient policies, strategies, and solutions to our environmental chaIlenges. The organization of the Proceedings reflects sessions and discussions during the workshop. The papers in the introductory Chapter summarize the positions of Drs. Glenn Suter (EPA) and Jim Wilson (Resources for the Future) regarding whether the use of often-expensive risk assessments in developing countries can be justified, given evolving regulatory institutions and limited resources.

Formaldehyde is ubiquitous in indoor and outdoor air, and everyone is exposed to formaldehyde at some concentration daily. Formaldehyde is used to produce a wide array of products, particularly building materials; it is emitted from many sources, including power plants, cars, gas and wood stoves, and cigarettes; it is a natural product in come foods; and it is naturally present in the human body as a metabolic intermediate. Much research has been conducted on the health effects of exposure to formaldehyde, including effects on the upper airway, where formaldehyde is deposited when inhaled, and effects on tissues distant from the site of initial contact. The U.S. Environmental Protection Agency (EPA) released noncancer and cancer assessments of formaldehyde for its Intergated Risk Information System (IRIS) in 1990 and 1991, respectively. The agency began reassessing formaldehyde in 1998 and released a draft IRIS assessment in June 2010. Given the complexity of the issues and the knowledge that the assessment will be used as the basis of regulatory decisions, EPA asked the National Research Council (NRC) to conduct an independent scientific review of the draft IRIS assessment. In this report, the Committee to Review EPA's Draft IRIS Assessment of Formaldehyde first addresses some general issues associated with the draft IRIS assessment. The committee next focuses on questions concerning specific aspects of the draft assessment, including derivation of the reference concentrations and the cancer unit risk estimates for formaldehyde. The committee closes with recommendations for improving the IRIS assessment of formaldehyde and provides some general comments on the IRIS development process.