Seven flight attendants were taken to hospital complaining of headaches caused by "odours in the cabin" on an American Airlines aircraft.

The crew on flight 1896, which landed safely in Orlando on Monday night, were said to have been involved in what are known as fume events. Seven staff were hospitalised, but none of the 89 passengers needed medical treatment.

According to American Airlines the Airbus A330 is currently undergoing a “thorough maintenance inspection”, but the airline has not yet identified what caused the odour. The flight attendants were released from hospital shortly after their arrival.

An American Airline forced to make an emergency landing in 2010 after a fume event Credit: GETTY

This is the third fume event to affect the aircraft in as many months, according to ABC News. The jet is alleged to have experienced a “dirty sock odour” on November 23 and a similar incident five days later.

“The health and welfare of our crews and customers continues to be our top priority at American Airlines,” the carrier said in a statement.

“We take cabin odor issues seriously and have devoted extensive efforts over time, including working with aircraft, engine and auxiliary power unit manufacturers, to address these types of concerns.”

Typically, fume events occur when engine oil and other toxic chemicals leak into the air circulated around the cabin. Campaigners claim this can cause “aerotoxic syndrome” in regular fliers, an illness linked with the deaths of at least two pilots, including British Airways’ Richard Westgate.

The coroner investigating his death ruled in February 2014 that fumes circulating in planes posed “consequential damage” to the health of frequent fliers.

However, the Civil Aviation Authority (CAA) has always maintained that cabin air is safe and that there is no evidence of long-term health effects.

Richard Westgate died in 2012 after claiming he'd been poisoned by toxic cabin fumes

Unite the Union told Telegraph Travel in November that it believes the aviation industry is downplaying serious toxic fume events onboard aircrafts.

“Fume events and continued exposure to contaminated cabin air can lead to serious ill health with long term debilitating effects on people’s wellbeing,” said Howard Beckett, Unite’s director of legal services.

“Brushing these serious incidents under the carpet is shameful and we urged the CAA to investigate and for the people involved in fume events to use our register or phone our hotline.”

Unite says it is pursuing 67 legal cases against UK airlines on behalf of former and serving cabin crew who say they have been affected by contaminated cabin air.

In response to Unite’s allegations, a British Airways spokesperson said: “Safety is always our priority. We continue to conduct thorough and detailed investigations which we share with the CAA.

“We always encourage our people to report any potential incident to allow us to investigate them.”