The U.S. Environmental Protection Agency (EPA) has declared emissions from aircraft using leaded gasoline a public health risk. This decision followed appeals for change by Santa Clara County and numerous environmental groups, as cited by Santa Clara County News.

Santa Clara County officials welcomed the EPA's decision and urged the entity to work with the Federal Aviation Administration (FAA) to expedite a transition to unleaded aviation fuel use for the nation's 170,000 piston-powered aircraft. Notably, a comparable transition for motor vehicles was enacted 25 years ago.

This official endangerment recognition came under the Biden-Harris administration, and Santa Clara County Supervisor Cindy Chavez pointed out the role played by Earthjustice and other organizations in advocating for the decision. The contributing was a scientific study carried out by Santa Clara County in 2021 on the lead exposure risks to children living near Reid-Hillview Airport, which found significantly elevated levels of lead in the blood of children in the area. As a result, Santa Clara County stopped sales of leaded fuel at their airports on January 1, 2022, according to Santa Clara County News.

Although dangerous, the availability of leaded fuel is not restricted by the endangerment finding. However, it does mandate that the EPA and FAA effect regulatory standards for lead emissions. This permits the Biden administration to continue its path towards eradicating leaded aviation fuel. However, county officials are pressuring the EPA and FAA to speed up the process and curb the damage to communities across the country.

While consensus for eliminating leaded fuel exists, there is a clause in the upcoming FAA reauthorization legislation that directs airports to continue supplying leaded aviation fuel. Over 100 local community groups and organizations are campaigning for Congress to strike this clause.

Unregulated by the EPA, leaded aviation fuel is accountable for 70% of air lead emissions. For over 15 years, environmental activists have lobbied the EPA to intervene. The harmful impact of lead pollution from aircraft using leaded fuel has been reported in the Reid-Hillview Airport study, which found that 13,000 adjacent children suffered adverse effects. The study demonstrated that the increase in blood lead levels in children living downwind from the airport was equivalent to levels observed in the Flint Water Crisis in Michigan.

About four million people dwell within 500 meters of the 20,000 airports used by the 170,000 piston-engine aircraft that still consume leaded aviation fuel. Approximately 600 schools are in the same range, putting at risk three million children within a kilometer of the runways. Health bodies concur that no level of lead exposure in the human body is safe, and even minor lead exposure can hinder cognitive ability and IQ development in young children.