US EPA

EPA has announced that the Second External Review Draft of the Integrated Science Assessment (ISA) for Particulate Matter (PM) have been made available for independent peer review and public review. The ISA reflects the latest scientific knowledge useful in indicating the kind and extent of identifiable effects on public health which may be expected from the presence of [a] pollutant in ambient air (42 U.S.C. 7408). This draft ISA document represents a concise synthesis and evaluation of the most policy-relevant science and will ultimately provide the scientific bases for EPA's decision regarding whether the current National Ambient Air Quality Standards (NAAQS) for PM sufficiently protects public health and the environment.

EPA released this draft document to seek review by the Clean Air Scientific Advisory Committee (CASAC) and the public (meeting date and location to be specified in a separate Federal Register notice). The draft document does not represent, and should not be construed to represent, any final EPA policy, viewpoint, or determination. EPA will consider any public comments submitted in response to this notice when revising the document.

PM is one of six principal (or criteria) pollutants for which EPA has established NAAQS. Periodically, EPA reviews the scientific basis for these standards by preparing an ISA (formerly called an Air Quality Criteria Document). The ISA and supplementary annexes, in conjunction with additional technical and policy assessments, provide the scientific basis for EPA decisions on the adequacy of the current NAAQS and the appropriateness of possible alternative standards. The Clean Air Scientific Advisory Committee (CASAC), an independent science advisory committee whose existence and whose review and advisory functions are mandated by Section 109 (d) (2) of the Clean Air Act, is charged (among other things) with independent scientific review of EPA's air quality criteria.

Key information and judgments formerly contained in an Air Quality Criteria Document (AQCD) for PM are incorporated in this assessment. Additional details of the pertinent literature published since the last review, as well as selected older studies of particular interest, are included in a series of annexes. This ISA thus serves to update and revise the evaluation of the scientific evidence available at the time of the previous review of the NAAQS for PM that was concluded in 2006.

The second external review draft ISA for PM will be discussed at a public meeting for review by CASAC, and public comments received will be provided to the CASAC review panel. A future Federal Register notice will inform the public of the exact date and time of that CASAC meeting.

U.S. EPA. Integrated Science Assessment (ISA) for Particulate Matter (Second External Review Draft, Jul 2009). U.S. Environmental Protection Agency, Washington, DC, EPA/600/R-08/139B, 2009.

On August 13, 2009 an updated version of the Second External Review Draft ISA was posted that includes linkage of references in all chapters and annexes. The updated version of the draft ISA also includes corrections to formatting issues in the text and some figures so that text on some pages has been shifted; however, no substantive changes have been made. In addition, the draft Annexes were also posted on August 13, 2009.

Submitting Comments: Comments on the draft ISA for PM (Second External Review Draft) or it's annexes may be submitted and reviewed using the e-Government Regulations.gov Web site. From the site, select Environmental Protection Agency and the keyword EPA-HQ-ORD-2007-0517 (for the docket ID) to comment on this report and supporting documents.