Analysis: Getting the lead out of our skies.
Toxic leaded gas remains in piston-engine planes, tainting nearby water, soil and children. Why do the feds refuse to act?
SEATTLE—The excitement of watching sea planes take off and land from Lake Union belies their hidden danger: leaded gasoline.
While lead was removed from automobile and other transportation gasoline more than two decades ago, it's still used in aviation gasoline, or "avgas," to prevent knocking in piston-engine aircrafts. According to the U.S. Environmental Protection Agency (EPA), avgas is the single largest source of lead emissions in the country.
Avgas released during flight has the potential to disperse lead widely in the environment, contaminating water bodies, soil near the air fields, and farms.
Lead is a well-known neurotoxicant, and children are particularly vulnerable to its devastating and irreversible impacts. The U.S. Centers for Disease Control and Prevention (CDC) says there is no safe level of blood lead in children. The EPA estimates that approximately 16 million people, including 3 million children, live or attend school within one mile of airports using leaded avgas.2
Researchers have found that children living close to airports with planes using avgas have higher blood lead levels than children living farther from those airports. Workers who service or refuel the aircrafts may also be exposed.
There are alternatives to avgas, and it is estimated that about 80 percent of the current piston fleet across the country could operate safely on these fuels without retrofitting. Europe already implemented policies to promote the use of unleaded alternatives. Yet, without regulatory updates in the U.S., there is little incentive for industries to change or for airports to provide alternatives.
What is the roadblock to these policy changes? To regulate lead under the Clean Air Act, the EPA must make an "endangerment finding" that documents the hazard of lead released from aviation gasoline. Despite petitions from multiple advocacy groups, however, the EPA has declined to make this determination and has insisted on the need for more data.
In the meantime, the Federal Aviation Administration (FAA) formed the Piston Aviation Fuel Initiative, a collaboration between FAA and industry to spur the development of additional avgas substitutes by 2018. Whether this effort delivers on its promise remains to be seen. And even if a replacement is "certified," the FAA estimated that a complete phase out of leaded fuel could take 11 years.
To spur changes in the absence of efficient federal progress, action at the state and local levels is needed. For example, requiring airports to provide unleaded gasoline or adopting taxes on leaded gasoline to promote use of alternatives.
Revenue generated could be used for soil lead testing or remediation at homes, schools, and parks near airports using leaded gasoline. We urge local policymakers to consider such initiatives in the coming legislative sessions.
A recent report from the Pew Charitable Trusts calculated that removing lead from aviation fuel would prevent a 5.7 percent increase in child blood lead across the country and result in $262 million in gross future benefits.
Given the known hazards of lead exposure and the existence of alternative aviation fuels, we have an ethical responsibility to eliminate the use of avgas and protect our population from such a significant source of lead pollution.
Rachel M. Shaffer is pursuing a PhD in Toxicology in the Department of Environmental and Occupational Health Sciences at the University of Washington Seattle School of Public Health. Steven G. Gilbert, PhD, is director of the Institute of Neurotoxicology and Neurological Disorders and an Affiliate Professor in the Department of Environmental and Occupational Health Sciences at UW Seattle.