Student died after using two to three ‘big bottles’ of laughing gas a day

Ellen Mercer said that she had burned her legs after spilling a gas canister on them

An inquest found found laughing gas played a hand in Ellen Mercer’s death (Supplied)

A student who may have been killed by long-term use of laughing gas was inhaling two to three “big bottles” of the substance each day, an inquest into her death has heard.

Ellen Mercer, 24, was taken to hospital by the emergency services in the early hours of February 9 last year after she reported that she was unable to walk and would fall over when she tried, Berkshire coroner’s court heard.

She was treated by medical staff at Wexham Park Hospital Emergency Department, but she died around 24 hours later at 12:52am on February 10.

Senior coroner Heidi Connor told the inquest that “part of her cause of death” related to “nitrous oxide gas”, also known as laughing gas.

The inquest heard that a post-mortem report found Ms Mercer’s death to have been caused by bilateral pulmonary thromboembolism, deep vein thrombosis, and “long-term complications of nitrous oxide use”.

Michaela Kirtley, an emergency medical technician from Phoenix Response Services, a contractor that worked for South Central Ambulance Service, attended Ms Mercer’s home on February 8.

When she arrived at the scene, she was shown to the bedroom by Ms Mercer’s boyfriend.

“I took notice of the room,” she said.

“There were no sheets on the bed at all. There was just the duvet, severely stained. The room was bare.”

She said the scene made it clear to her that she was dealing with a “vulnerable person”.

She said Ms Mercer “was talking as normal”, and the only one of her vital signs that was outside the normal range was her heart rate, which could have been due to anxiety.

Ms Mercer told her that she had burned her legs after spilling a gas canister on them and that she had been unable to walk or go to the toilet for two weeks, she said.

She said the 24-year-old looked six months pregnant.

She checked the wounds on Ms Mercer’s legs, which she described as “pussy”.

Ms Mercer’s boyfriend showed her a box of gas canisters, which she identified as nitrous oxide.

“I had never seen such big bottles,” she said.

She told the inquest that the canisters were 600g and that Ms Mercer’s boyfriend said she took “two to three bottles” per day, but had slowed down in the last couple of weeks.

Ms Mercer told her she had passed out and the bottle had fallen on her legs.

An ambulance then took Ms Mercer to hospital.

At the time of the student’s death, possession of laughing gas with the intent of getting high was not illegal. It was banned by the Government, and made a Class C drug, in November 2023.

The inquest continues.