Areas designated as not meeting the standard will need to develop and implement plans to reduce pollution to meet the lead standards. Nonattainment areas must meet the standards by Dec. 31, 2015.
EPA will designate areas as meeting or not meeting the standards in two rounds. In the first round, EPA is designating areas that do not meet the standards based on air quality monitoring data from the existing lead monitoring network. In October 2011, EPA will use data from new monitors to complete a second round of designations that will classify the remaining areas in attainment, unclassifiable or nonattainment.
In October 2008, EPA strengthened the nation’s air quality standards for lead tenfold to 0.15 micrograms of lead per cubic meter of air. The agency also finalized requirements for new monitors to be located near large sources of lead emissions. EPA has data from existing monitors indicating violations of the standards, and is currently collecting data from new monitors that began operation in January 2010.
Lead emitted into the air can be inhaled or can be ingested after it settles. Ingestion is the primary route of human exposure. Children are the most susceptible because they are more likely to ingest lead and their bodies are developing rapidly. There is no known safe level of lead in the body.
National average concentrations of lead in the air have dropped almost 92 percent nationwide since 1980, largely the result of the agency's phase-out of lead in gasoline. Lead in the air comes from a variety of sources, including smelters, iron and steel foundries and general aviation gasoline.
More information on the designations, visit http://www.epa.gov/leaddesignations.