Several Aer Lingus crew members on flight EI166 had reportedly been exposed to Toxic Fumes which forced the flight to make an emergency diversion back to Dublin. The crew members were hospitalized and are receiving treatment for potential fume inhalation.
 

The Incident

Aer Lingus flight EI166 operated by an Airbus A320 departed from Dublin Airport (DUB) at 1:25 p.m. local time on March 9 and was en route to London Heathrow (LHR), but less than an hour after taking off cabin crew members were allegedly exposed to "toxic fumes" which caused the aircraft to divert to Dublin Airport (DUB). The A320 was delivered to the Irish carrier in April 2005, Aer Lingus has 29 of them in their fleet which 27 are actively operating. According to the reports the plane reached 29,000ft over the Irish Sea and entered UK airspace, at which time the pilots contacted Air Traffic Control (ATC) to report the occurrence of "fumes". 

"Yesterday, Aer Lingus flight EI166 to London Heathrow experienced a technical issue and returned to Dublin Airport, landing normally. No medical treatment was required for crew following assessment," they said and added that Aer Lingus “re-accommodated all passengers yesterday.”
 

A Previous Toxic Fume Incident

Tom O'Riordan, a former Aer Lingus captain claims that he was "poisoned by toxic air" while operating as a captain on an Aer Lingus flight and he took his concerns to X (formerly known as Twitter) by saying, "A special word to our 6 colleagues and their passengers who were poisoned today by toxic fume on an Aer Lingus aircraft. Having been there, we are here for you."
 

He also shared his own experience in a post:
"On June 5th, 2023, I was poisoned by toxic air fumes whilst operating EI-DEN from Lhr to Dub. Following which I was taken by ambulance to hospital and admitted for 5 days. I continue to live with serious symptoms related to this incident. I have attempted to get assistance from Aer Lingus and have received no assistance. I have learned that Aer Lingus experienced 22 reported fume events between January 2023 and January 2024, and that these incidents are on the increase. In September 2023, a technical notice related to fume events was issued to Aer Lingus engineers. No information on fume incidents have been disseminated to crew or passengers. I have previously asked for fair compensation for myself, the dissemination of information on fume events and a health protocol for persons who have been subjected to a fume events. Also, I requested that persons who are now living with effects of fume events be openly and fairly engaged. None of this has happened."

Aerotoxic Syndrome poses a health risk for passengers and crew on airplanes. This condition arises when leaks or malfunctions allow engine oil or hydraulic fluids, which can contain harmful toxins, to contaminate the plane's air supply. While the exact frequency of Aerotoxic Syndrome remains unclear due to a lack of transparent reporting by some airlines, all carriers must take this issue seriously. By implementing stricter maintenance protocols, investing in improved air filtration systems, and open communication about potential incidents, airlines can prioritize the well-being of everyone onboard.