Risk-Based Assessment and Management Framework

Abstract

This chapter reviews current risk assessment concepts and practices as they apply to risk-based, multipollutant air quality management. Key risk assessment elements are introduced. The use of risk and benefit analysis to inform air quality management decisions is described. The concept of accountability is introduced and its linkages to prospective and retrospective forms of risk assessment are discussed. Risk assessment can be applied in an accountability framework to improve air quality management decisions. The current use of risk assessment techniques related to air quality management is reviewed for Canada, Mexico, and the United States. The need to deal with multiple risk characterization metrics in multipollutant risk assessments is a key challenge, because there is not a common basis of quantification for all adverse outcomes. For human health outcomes, risk characterization often focuses on cancer versus non-cancer and individual versus population risk metrics. There are no standard metrics for comparing human health and ecosystem risks. Appropriately chosen and consistently applied metrics are needed for analysis and measurement under an accountability framework. The chapter concludes with a discussion of risk communication and the knowledge gaps limiting the use of risk assessment in multipollutant regulatory applications.