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Lead Designations

Learn About Lead Designations

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Lead designations process

Breathing air containing lead can cause a range of adverse health effects, most notably in children. Exposures to low levels of lead early in life have been linked to effects on IQ, learning, memory, and behavior. Elevated lead in the environment can result in decreased growth and reproductive rates in plants and animals, and neurological effects in vertebrates.  Reducing levels of lead pollution is an important part of EPA’s commitment to a clean, healthy environment.

Title I of the Clean Air Act requires that within two years after EPA sets a new National Ambient Air Quality Standard (NAAQS), or revises an existing standard, we must designate areas in the United States as being in "attainment" (i.e., meeting) or "nonattainment" (i.e., not meeting) with the standard.

The Clean Air Act requires states to submit, and gives tribes the opportunity to submit, initial area designation recommendations within 12 months following promulgation of a new or revised NAAQS. For the 2008 lead standards, EPA completed lead designations in two rounds. In the first round, EPA designated as “nonattainment” any area that violated the 2008 lead standards based on air quality data from 2007-2009. EPA took an additional year to make final designations decisions for all other areas of the country to allow additional lead air quality data to be collected and evaluated. In the second round, EPA designated those remaining areas as meeting or not meeting the 2008 lead standards based on data from 2008-2010. Although tribes are not required to provide recommendations they are invited to do so. Some tribes participated in this process.

Basis for air quality designations

EPA’s final designations are based on air quality monitoring data, recommendations submitted by states and tribes and other technical information. EPA provided guidance for the lead designations process in the preamble to the lead NAAQS rule.