Integrated Science Assessment (ISA) for Particulate Matter (Final Report, Dec 2019)

The Integrated Science Assessment (ISA) for Particulate Matter is a concise synthesis and evaluation of the most policy-relevant science, and has been prepared as part of the review of the primary (health-based) and secondary (welfare-based) National Ambient Air Quality Standards (NAAQS) for Particulate Matter (PM) under the Clean Air Act. Welfare effects are non-health effects which, according to the Clean Air Act include, but are not limited to, effects on soils, water, crops, vegetation, animals, wildlife and climate. The PM ISA, in conjunction with additional technical and policy assessments, provides the policy relevant scientific information necessary to conduct a review of the current primary and secondary air quality standards for particulate matter sufficiently protects public health and welfare.

Particulate matter is one of six principal (or criteria) pollutants for which EPA has established National Ambient Air Quality Standards (NAAQS). The Clean Air Act requires EPA to periodically review the science for six major air pollutants, including PM.

The Integrated Science Assessments (ISAs) summarize the science related to the health and welfare effects associated with these pollutants by providing a comprehensive review of the policy-relevant scientific literature published since the last NAAQS review. The ISA is a critical part of the scientific basis for updating the NAAQS.


The PM ISA ERD reflects a systematic evaluation of the peer-reviewed literature published since the completion of the 2009 PM ISA that builds off the scientific conclusions presented in previous assessments of the health and welfare effects evidence for PM. This ISA is the initial draft of the current state of the science on the health and welfare effects of PM that will ultimately result in the final PM ISA that will serve as the scientific foundation of the ongoing review of the PM NAAQS, which was last completed in 2012.


U.S. EPA. Integrated Science Assessment (ISA) for Particulate Matter (Final Report, Dec 2019). U.S. Environmental Protection Agency, Washington, DC, EPA/600/R-19/188, 2019.


Date Description
01-Oct 2018EPA released an external review draft for public review and comment. The draft document will be discussed at a CASAC meeting in December 2018.
02-Nov 2018EPA announced that the peer review meeting for the review of the PM ISA in December 2018. [Federal Register Notice Nov 6, 2018]
04-Mar 2019On March 7, 2019, EPA's Science Advisory Board (SAB) released the 03-07-19 Draft CASAC Review of the EPA’s Integrated Science Assessment for Particulate Matter (External Review Draft – October 2018).
06-Dec 2019EPA updated the report based on comments on the draft and prepped the final report for release. [Federal Register Notice Jan 27, 2020]
07-Jan 2020EPA released the final report and announced this in the Federal Register.
08-Sep 2021EPA re-posted the final assessment with an errata sheet of updates.