The Environmental Protection Agency (EPA) recently finalized its new standard for lead. The standard was revised from 1.5 micrograms per cubic meter (ug/m3) of air, to 0.15 ug/m3. The final rule is at www.epa.gov/air/lead.

Where Does Lead Come From?
Lead is a toxic, naturally occurring metal used in many manufactured products found in and around our homes, such as lead-based paint. The major sources of lead emissions have historically been motor vehicles and industrial sources. Lead emissions from motor vehicles have largely been eliminated since lead has been removed from gasoline. The EPA indicates that lead emissions from transportation had declined 95 percent between 1980 -1999. Currently the highest sources of lead air emissions are from lead smelters, waste incinerators, utilities, and lead-acid battery manufacturers.

Why Does It Matter?
The revised standard increases protection for children and other at risk populations against a variety of adverse health effects. Lead is persistent in the environment and accumulates in soils and sediments through deposition from air sources, direct discharge of waste streams to water bodies, mining, and erosion. Ecosystems near point sources of lead demonstrate a wide range of adverse effects including losses in biodiversity, changes in community composition, decreased growth and reproductive rates in plants and animals, and neurological effects in vertebrates.

Health and Environmental Impacts
Airborne lead can be inhaled or, after it settles out of the air, can be ingested. Ingestion is the main route of human exposure. Once taken into the body, lead distributes throughout the body in the blood and accumulates in the bones. Exposure to lead is associated with a broad range of health effects, including the oxygen-carrying capacity of the blood, central nervous system, cardiovascular system, kidneys, and immune system.

Children are more vulnerable than adults to the damaging effects of lead in air. They breathe in more air per minute than adults and breathe through the mouth more often than adults. Children typically spend more times outdoors and are more physically active. Lead exposure also occurs through hand-to-mouth activities. Lead effects children much more than adults as their brains are still developing and more susceptible to the poisonous effect.

Ambient Air Monitoring
The new standard requires ambient air monitoring near large sources of lead emissions and in urban areas with more than 500,000 people. The DNR is in the process of reviewing recent emission inventory reports for lead emissions to determine where ambient air quality monitors would be required. Facilities with emissions above or near the threshold specified in the rule may be contacted by the DNR for additional information.

Key Dates

Much of the information found on this page was obtained from the EPA's website. For additional information please visit www.epa.gov/air/lead.