What is airborne lead?
Lead (Pb) is a metal used commonly in many industries, including construction, mining, and manufacturing. People working near products and materials that contain lead can unknowingly swallow or breathe in harmful amounts of lead dust or fumes. Lead can be absorbed through the skin.
Where does lead come from?
Major sources of lead (Pb) in the air are industrial metals processing and piston-engine aircraft operating on leaded aviation fuels. Other sources are waste incinerators, utilities, and the manufacturing of lead-acid batteries. The highest air concentrations of lead are commonly found near lead smelters.
In the past, leaded gasoline caused motor vehicle exhaust to be the main source of lead emissions. Since its removal from gasoline, the air emissions of lead from the transportation and automotive industries have declined some. But since it was emitted in such large amounts, lead is present in many soils, especially urban soil, and can get resuspended into the air.
How is lead measured?
Chemical concentrations in the air are measured by units of the substance (milligrams, micrograms, nanograms, picograms) per volume of air as cubic meters or cubic feet. Lead is typically expressed as micrograms per cubic meter (µg/m3). In health tests, blood lead levels (BLL) are taken in micrograms of lead per deciliter of blood (µg/dL).
The measurement of airborne lead requires an air sampling pump affixed with a lead-capturing membrane. This reports a number based on how much lead is caught by the membrane and how much air was pulled through the sampling device.
What are the standards for lead pollution in the United States?
National Ambient Air Quality Standards (NAAQS) for pollution specify a maximum amount of a pollutant to be present in outdoor air.
Currently, the EPA has primary (health-based) and secondary (welfare-based) standards in place for lead. These standards are based on average numbers over the course of three months.
| Pollutant | Standard Type | Mass per Volume | Terms | Date Established |
| Lead (Pb) | Primary | 0.15µg/m3 | Not to be exceeded, averaged over a three month period | 12 November 2008 |
| Lead (Pb) | Secondary | 0.15µg/m3 | Not to be exceeded, averaged over a three month period | 12 November 2008 |
How does lead affect people?
Adults most commonly are exposed to lead in occupational settings or under unsafe home renovation conditions. Young children can be exposed to lead with normal hand-mouth movements, like babies crawling on the floor and touching their faces, or putting toys and other objects in their mouths.
Once lead is absorbed into the body, the blood carries it through the body and deposits it in the bones where it can accumulate. Lead is excreted from humans very slowly, so exposures to small amounts of lead from a variety of sources can accumulate to harmful levels. Because of its presence in blood, lead can adversely affect multiple organ systems of the body.
Lead pollution affects all age groups. In adults, lead poisoning can cause reproductive issues, high blood pressure, kidney disease, digestive problems, nerve disorders, memory and concentration problems, and muscle and joint pain. There is evidence that lead exposure can lead to cancer. If a pregnant person is exposed to elevated levels of lead, it can cross the placenta and enter the baby’s blood. This increases the risk of miscarriage, premature birth or low birth weight, and developmental effects in the brain and nervous system. In children, adverse health effects of lead exposure are often irreversible and include brain damage and developmental disabilities. Lead poisoning is often unrecognized in children and if undetected, can result in slowed growth, hearing damage, hyperactivity or lethargy, behavioral issues, reduced intelligence, anemia, and liver or kidney damage. In rare cases, ingested lead can cause seizures, comas, or death.
Who is most at risk for adverse health effects from lead?
Children six years old and younger are the most susceptible to the effects of lead. Another at-risk group is pregnant people. Lead can accumulate in our bodies over time and be stored in the bones with calcium. During pregnancy, lead is released from the parent’s bones along with calcium and can pass into the fetus through the blood or to an infant during breastfeeding.
How does airborne lead affect the environment?
Lead is persistent in the environment and can be added to soil through deposition from direct sources of lead air pollution. For example, the soil at the grassy runway of a small airport might be full of lead. Other sources of lead to ecosystems include mining and the direct discharge of waste streams to water bodies. Elevated levels of lead in the environment can result in decreased growth and reproduction in plants and animals, as well as neurological issues in vertebrates.