There’s good reason we’ve eliminated the use of lead in everything from pipes and paint to auto fuels: Scientists have known for decades that no level of the highly toxic metal is safe for humans or wildlife.
Even small amounts of lead pollution can cause nervous system damage, reduced intelligence, behavioral changes and developmental harms that are often irreversible, especially in children.
Given those well-documented risks, the millions of Americans who live or work in neighborhoods bumping up against the nation’s airstrips have no reason to suspect that the small propeller planes routinely humming overhead are spewing dangerous levels of lead pollution.
But they are. The reality is that leaded aviation fuel, still used in the majority of small propeller planes, is the nation’s largest remaining source of lead emissions, according to the Environmental Protection Agency.
Federal regulators have been aware of that alarming truth for years but failed to act. Finally, in October, the EPA took the first step toward possibly fixing the problem by issuing a proposal stating the planes’ lead emissions are likely to endanger public health.
What the EPA may, or may not, end up doing about that “proposed determination” remains to be seen. But the agency is taking comments on the issue through the end of the year with plans to consider addressing the problem in 2023.
Regulators know the need for action is great, particularly in Greater Seattle.
More than 80% of lead emissions in the Puget Sound area come from the aviation sector, with lead pollution at much higher levels near airports than in the general environment, according to a study by the Puget Sound Clean Air Agency.
Dangerous lead exposures are much more common near smaller airstrips — like those at Boeing Field, Renton and Auburn — than Seattle-Tacoma International Airport. Jets, like those flown by commercial airlines, use a kerosene-based fuel that does not contain lead.
The EPA estimates that about 0.02 tons of lead emissions are coming from Sea-Tac, but 1.53 tons of lead emissions are coming from other King County airports. More than 90% of that pollution comes from Auburn and Renton municipal airports, Boeing Field and Crest Airpark.
The agency estimates that about 16 million Americans live less than a mile from an airport serving mainly prop planes. And about 3 million children attend schools located within a mile of one of those airports.
Assessments of children have found that the closer they lived to an airport, the higher the concentrations of lead in their blood. Those risks include not only inhaling lead directly from the air but from exposure to lead that settles into soils and dust.
Airborne lead concentrations exceed the EPA’s safety standards for humans at distances of more than a half mile downwind of airports frequented by prop planes.
And pollution from leaded aviation fuel is a serious environmental justice issue: People of color with low incomes are much more likely to be subjected to lead emissions from airplane fuel than King County’s white residents.
The EPA’s proposed “endangerment finding” that leaded aviation fuel threatens public health and welfare is merely the first step. The agency must now finalize that determination and issue common sense standards to eliminate lead in aviation fuel in small planes, just as it did for cars. Leaded gasoline for passenger cars was banned in the U.S. in 1996.
As has always been the case with efforts to remove lead, there will be pushback from the aviation and fuel industries. Alternatives to leaded gasoline have been available for much of the nation’s small plane fleet for years and a new unleaded alternative was just given blanket approval by the Federal Aviation Administration for all piston aircraft.
The alternatives are there, but producing new fuels to scale and transitioning airports across the country to unleaded alternatives will take excruciatingly long without pressure to move quickly. Waiting for the industry to do the right thing on its own timeline is not an option.
The reality is that the EPA knows what it has to do right now: It must end the use of leaded aviation fuels, period. The sooner, the better.
