The Federal Aviation Administration (FAA) has received thousands of reports since 2010 about toxic fumes from jet engines leaking into the cockpit and cabin of airplanes, according to an investigation done by The Wall Street Journal.
The leaks are due to a commonly used airplane design known as “bleed air” that pulls air from the engine into airplanes so those onboard can breathe.
The increase in reports is largely driven by Airbus A320s, which the three largest U.S. airlines use. The aircraft reported seven times the rate of fume events than their Boeing 737, which does not use the “bleed air” design.
For JetBlue and Spirit, both of which primarily use Airbus aircraft, the number of fume incidents saw a combined 660 percent surge between 2016 and 2024.
The fumes, often described as smelling of “wet dog” and “nail polish,” have led to emergency landings and passengers and crew members falling ill, according to reports obtained by the Journal.
Most emitted fumes, which consist of carbon monoxide and unspecified quantities of neurotoxins, aren’t toxic and have mild to no symptoms, but long exposure could lead to more severe side effects. For years, aircraft manufacturers and airline lobbying groups have downplayed the risks of inhaling these toxic fumes, according to The Journal.
The FAA on its website cites a 2015 review that found fume incidents reported on major U.S. airlines at a rate of “less than 33 events per million aircraft departures,” or about 330 events per year.
The numbers could be higher, as crew members aren’t required to report on every fume event.
The airline industry has funded studies to disprove claims that fume leakage in aircraft cause significant harm, while opposing legislation calling for increased safety measures to avoid fume leaks, according to the Journal.
Congress has attempted to introduce legislation at least 19 times about fume contamination for over two decades, according to a deposition transcript obtained by the Journal of Boeing’s 737 chief product engineer, Julie Brightwell.
In 2024, Rep. John Garamendi (D-Calif.) and Sen. Richard Blumenthal (D-Conn.) introduced a bill that would provide sensors on aircraft and more thorough investigations. After industry pushback, the bill, which was signed into law last year, only required research about fume leakage and better reporting on incidents.
In August, new legislation was introduced by Rep. Maxwell Frost (D-Fla.) to require filters on passenger airplanes that would completely eliminate fume leakage on planes within seven years.
The Hill reached out to Frost’s office for comment on the status of the bill.
