The Boulder County Commissioners voted on Jan. 17 to support an Environmental Protection Agency (EPA) finding that could create regulatory standards for lead emissions from aircraft engines.
The EPA’s “endangerment finding,” released in October 2022, says that lead emissions from some aircrafts cause or contribute to lead air pollution, which can “reasonably be anticipated to endanger public health and welfare.”
If the EPA makes a “final determination,” slated for later this year, the agency will propose a federal regulation.
More than 10 local governments from across the country joined the Boulder County Commissioners in signing a letter of support for the endangerment finding, calling on the EPA to rapidly ban leaded aviation gas (avgas) nationwide by the end of 2025.
“We regularly hear from residents about air pollution from aviation and its dangerous impact on our community and specifically children’s health,” Commissioner Ashley Stolzmann said in a press release. “We applaud this move by the EPA and ask that they move quickly to regulate and ultimately phase out the use of leaded gas in aviation.”
In the letter, signers say “the EPA has known for decades that lead air pollution and its impacts on communities constitute a public health crisis.”
Last February, the Federal Aviation Administration (FAA) joined the Elimination Aviation Gasoline Lead Emissions (EAGLE) Initiative to accelerate a transition to lead-free aviation fuel. Through EAGLE, the FAA will phase out these fuels by the end of 2030.
The majority of aircrafts that use leaded avgas are piston-engine aircrafts — the kind that typically carry two to 10 passengers. The EPA says these are the largest single source of lead emissions to the air in the U.S. Larger jets used for commercial transportation don’t use leaded fuel.
There are a handful of airports in and adjacent to Boulder County that use these smaller piston-engine aircrafts, like the Boulder Municipal Airport, Vance Brand Municipal Airport in Longmont, and Rocky Mountain Metropolitan Airport in Broomfield.
According to the EPA, “lead can affect almost every organ and system in your body.” Children and pregnant women are most at risk, but lead exposure is also harmful to adults. People are exposed to lead through a variety of means, including industrial facilities and lead-based paint (which was federally banned for residential use in 1978) that can seep into air, water and soil.
A major source of lead in the air is from leaded avgas, but the EPA says levels of lead in the air decreased by 89% between 1980 and 2010 after regulatory efforts to remove lead from motor vehicle gasoline.
Avgas is the last remaining leaded transportation fuel in the U.S. Leaded fuel is used for these specific engines because it improves efficiency, performance and engine safety.
Bill Hayes, air quality program coordinator at Boulder County Public Health, says the county, state and feds don’t monitor for airborne lead in Colorado; 2015 was the last year there was any air monitoring for lead in Colorado for a regulatory purpose, which stopped because of low concentrations.
In 2014, the National Emissions Inventory reported lead emissions from the Centennial Airport were 0.77 tons per year, which was below the threshold (1 ton per year) for continued monitoring of the site.
Now, Hayes says his concern about airborne lead emissions is low.
“Not to say it isn’t happening, but we’re not aware of issues of elevated blood levels due to inhalation of airborne lead,” he says.
Hayes’ primary concern is children who live in close proximity to these airports.
According to the EPA, children’s exposure to lead can cause “irreversible and life-long health effects.” There’s no safe blood lead level in children, who can experience negative side effects to IQ and academic achievement from even low levels of lead.
In 2010, the EPA estimated that “up to 16 million people reside and 3 million children attend school in close proximity to airport facilities servicing piston-engine aircraft that are operating on leaded avgas.” The EPA and FAA have estimated that leaded avgas is used by between 170,000 and 220,000 piston-engine aircraft at 20,000 airports across the country.
Hayes says it’s also an environmental justice issue, with lower income residents typically living closer to these airports.
In Hayes’ estimation, it’s time to move to lead-free aviation fuel.
“Since it is avoidable and unnecessary,” he says, “we want to support the EPA’s efforts to get rid of lead in all fuels.”