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Integrated Science Assessment (ISA) for Ozone and Related Photochemical Oxidants

The Issue

Ozone is a gas that occurs both in the Earth's upper atmosphere and at ground level where it is a key component of urban smog. Ground-level ozone causes a variety of effects on human health, vegetation, and ecosystems and it affects climate. Human exposure to ozone is associated with respiratory and cardiovascular effects as well as premature death. Ozone exposure causes visible foliar injury, decreases plant growth and affects ecosystem community composition.

Peak ozone levels typically occur during hot, dry, stagnant summertime conditions. Millions of Americans live in areas where ozone levels exceed EPA's health-based air quality standards, primarily in parts of the Northeast, the Lake Michigan area, parts of the Southeast, southeastern Texas, and parts of California.

EPA Action

EPA's ozone research efforts are focused on improving emissions estimates, determining health and ecological effects, and improving modeling capabilities. EPA's National Center for Environmental Assessment periodically evaluates the latest research concerning the public health and welfare effects of ozone and publishes the most up-to-date findings in an assessment called an Integrated Science Assessment. This document provides the scientific basis for the establishment of the most current national air quality standards for ozone. EPA released the Integrated Science Assessment for Ozone and Related Photochemical Oxidants Final Report in February 2013.

History of the Ozone and Related Photochemical Oxidants Assessments

   
Feb 2013 EPA released the final report of the Integrated Science Assessment for Ozone and Related Photochemical Oxidants (EPA/600/R-10/076F).[Federal Register Feb 15, 2013] This is the latest version.
Feb 2006 EPA released the final report of the Air Quality Criteria Document for Ozone and Related Photochemical Oxidants (EPA/600/R-05/004). [Federal Register Feb 28, 2006]
1996 EPA released the final report of the Air Quality Criteria for Ozone and Related Photochemical Oxidants (EPA/600/P-93/004).

Peer-Reviewed Literature

While working on the assessment of ozone, EPA used the Health and Environmental Research Online (HERO) database to augment the underlining literature that supported the final assessment.

See: ISA-Ozone and Related Photochemical Oxidants (2012 Final Project Page)