On July 19, 1999, the authors published a notice in the Federal Register entitled 'National Air Toxic Program: The Integrated Urban Air Strategy' (Strategy) that outlined the U.S. Environmental Protection Agency's (EPA's) plans for addressing cumulative health risks in urban areas. The Strategy presented the authors' plan for future actions to reduce emissions of air toxics and improve our understanding of the health risks posed by toxics in urban areas. Section 112(k) of the Clean Air Act (CAA) requires the EPA Administrator to submit two Reports to Congress on actions taken under the CAA that reduce the risk to public health posed by the release of hazardous air pollutants (HAP) from area sources. This Report to Congress (Report), originally due in 1998, was prepared to meet the first part of that requirement. In addition, it expands on much of the information provided in the Strategy, such as the methodology for developing the emissions inventory, identifying the 33 urban HAP and identifying the area source categories that will be subject to regulation. Furthermore, this Report summarizes existing information on risk assessments that have been conducted in various urban areas. These studies were performed by EPA and various States over the last several years. Taking into consideration the uncertainties and limitations of each study, these assessments provide useful information on the potential nature and magnitude of exposures and health risks in urban areas. Finally, this Report also provides a very detailed discussion of 13 research needs to address in achieving the goals of the Strategy. These needs were identified in the following areas: exposure assessment, health effects, dose-response assessment, risk assessment, risk characterization and risk management. In addition, Chapter 6 of this Report provides a summary of ongoing EPA activities to address those needs.

EPA Project Officer: Jaime Pagán. "July 2000." Includes bibliographical references. "EPA-453/R-99-007."