It's believed two staff fell unconscious and some people complained of "burning eyes and itchy skin" before a US-bound flight made an emergency landing in Dublin Airport.
The flight from London Heathrow to Philadelphia had to turn back for Ireland after some cleaning fluid apparently spilled out.
It's claimed two crew were temporarily unconscious while some passengers reported burning eyes and irritated skin.
Flight AA729 left London at around 11.14am this morning and was scheduled to arrive in the states at 1.44pm.
The plane was holding 287 passengers and 12 crew members.
It had been a few hundred miles off the coast of Kerry when it turned back.
A spokesperson for American Airlines confirmed the diversion and said that a medical team has met the passengers and crew to evaluate if they need assistance.
"American Airlines flight 729 from London Heathrow to Philadelphia diverted to Dublin due to an odor caused by a spilled cleaning solution in the galley."
"The flight landed safely in Dublin at 1:15 p.m. local time, and taxied to the gate."
"Medical personnel have met the aircraft to evaluate any crew members or passengers who may need additional assistance."
A Dublin Airport spokesperson also confirmed it was diverted into Dublin Airport for a medical emergency.
She said: "The aircraft landed safely at approx. 13.20.
"As per standard operating procedures there was a full turn out of Dublin Airport’s emergency fire services."
