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2012 EPA Research Progress Report

Integrated Science Assessments: Gathering the Best Air Science to Protect Human Health and the Environment

EPA sets National Ambient Air Quality Standards (NAAQS) for six “criteria” air pollutants—ozone, particulate matter, carbon monoxide, sulfur dioxides, nitrogen oxides, and lead—considered harmful to human health and the environment.

Interdisciplinary teams of EPA scientists prepare the Integrated Science Assessments (ISA) that review, synthesize, and evaluate the most policy-relevant science to serve as a scientific foundation for the review of NAAQS. The ISAs synthesize relevant information from a large body of literature, generally encompassing thousands of studies, from across scientific disciplines including atmospheric chemistry, exposure science, epidemiology, animal and human toxicology, and terrestrial and aquatic ecology.

All ISAs are vetted through a rigorous scientific peer review process, which includes two reviews by the Clean Air Scientific Advisory Council, and are made available for public review and comment.

During 2012, EPA scientists continued to make significant progress in developing ISAs. In February, the Agency released the second external review draft of the ISA for lead for public review and comment, and in November released the third draft of the lead ISA. In June, EPA released the third external review draft of the ISA for ozone and related photochemical oxidants for public review and comment.

EPA also held a “kickoff” workshop to initiate the next review of the health-based NAAQS for nitrogen oxides, in keeping with the Clean Air Act requirement for periodic reviews of the standards.

In addition, EPA scientists are laying the groundwork for incorporating multipollutant analyses into their assessments. The Agency is currently developing multipollutant science documents to help evaluate the impacts of ambient air pollution mixtures on health and climate. The multipollutant assessments are expected to help EPA scientists and managers better understand uncertainties about the effects of pollutants within the air pollution mixture. The multipollutant assessment work will also stimulate additional research and data gathering activities to benefit future assessments.

Integrated Science Assessments Released in 2012:



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