Woman dies and another fighting for her life in hospital after cryotherapy session 'poisons' them

Police are investigating after a woman died and another was left in critical condition following a cryotherapy session at a high-end gym in Paris.

The deceased was an employee at the gym, said to be 29 years old, while the injured woman, who was a client, was 34.

It was said that the staff member was supervising her during a cryotherapy session on Monday (14 April), before the session ended in tragedy.

The employee was pronounced dead at the scene, while the client was transported to hospital.

It is believed that a nitrogen leak in a cryotherapy chamber at the fitness centre caused the death in the freezing-cold tank, as both victims collapsed when oxygen in the room was displaced by nitrogen, authorities said.

While emergency services were quickly on the scene, they were unable to revive the employee.

A woman at a Paris gym was found dead following the accident (Getty Stock Image)

She was believed to have suffocated, while officials stated that the client was 'between life and death' at the Lariboisière hospital.

It has also been reported that three more staff members needed treatment for mild injuries, while 150 people were swiftly evacuated from the luxury gym.

A police investigation is currently underway to determine the exact cause of death, as it is believed the pair were 'poisoned' by the apparent leak.

It was also reported that plumbing work had taken place in the gym earlier in the day.

Paris prosecutors have asked for an autopsy and toxicological reports to help determine the exact cause of the accident.

What is cryotherapy?

Cryotherapy is a medical treatment that can freeze and destroy abnormal tissues, though it is quite popular among elite sports athletes.

The likes of Cristiano Ronaldo, LeBron James and Usain Bolt have used the treatment that can allegedly bring about a number of health benefits such as muscle recovery and a reduction in inflammation.

It uses liquid nitrogen or argon gas to achieve its freezing temperatures of between -110°C and -140°C.

Spas, gyms, and fitness centres across the world offer cryotherapy to clients at a premium, though it remains controversial.

Cryotherapy is a popular method used by athletes (Getty Stock Image)

Health risks of cryotherapy

Accidents can happen in non-medical cryotherapy settings, with many caused by asphyxiation.

They can be fatal, as liquid nitrogen, which cools the chambers, can displace oxygen molecules in the air if the ventilation is poor.

This has caused deaths in the US in the past, as a 24-year-old spa worker died after being trapped in a cryotherapy chamber overnight in Las Vegas, Nevada.

A member of the gym said via The Times: “I heard from colleagues that the gym was closed due to a death caused by a nitrogen leak. I’ve always been told that cryotherapy can be dangerous.”

Gym management confirmed they were working with local authorities.

LADbible has reached out to the Paris gym and the Paris Prosecutor General's Office for comment.