An American Airlines flight was forced to divert to Ireland after a cleaning fluid spill left two crew temporarily unconscious and passengers with burning eyes and itchy skin.

Flight AA729 from London Heathrow to Philadelphia was over south west Ireland when it turned back about an hour after takeoff and diverted to Dublin Airport, where it landed safely at 1:15 p.m. local time.

“Medical personnel have met the aircraft to evaluate any crew members or passengers who may need additional assistance,” an American Airlines spokesperson told via email.

“Two crew members and one customer were taken to the hospital for evaluation.”

The Airbus A330-300 jet, with 287 passengers and a crew of 12 on board, was about 250 km southwest of Valentia in County Kerry when crew made contact with air traffic controllers to advise them of their emergency, according to Ireland’s national broadcaster RTE.

In an audio recording, the pilot explained that although the product was believed to be non-toxic, the crew required immediate assistance.

He said: "We’ve actually covered the container of the substance. It was a cleaning product that was used at London Heathrow.

"It was spilled and for some reason the container itself was left behind in the aircraft in one of the lavatories and continued to seep into the carpeting and produce what I’m told is not, it is not a toxic substance.

"We require paramedics to come on board the airplane and render immediate assistance. We’ve had two of our flight crew staff made, excuse me, the cabin staff have actually lost consciousness, but I think they’re back to a state of consciousness just now and there are general complaints about burning eyes and skin problems."

Passenger Katie Phillips wrote on Twitter that the spillage "led to sickness outbreak and an emergency landing."

Many of those on the plane were athletes on their way to the UIPM Biathle/Triathle World Championship in Florida, according to The Mirror.

The Daily Telegraph reported that the leaking product is believed to be an aircraft interior cleaner made by Callington, a leading specialty chemicals manufacturer.