A great-grandmother fears youngsters are dicing with death as a new 'hippy crack' craze sweeps part of the city - after she found more than 100 discarded gas bottles in the street.
The concerned resident spoke out after she discovered 116 empty cream chargers within a matter of days earlier this month in an alleyway close to her Woodhouse home.
The chargers should be used to dispense cream onto cakes or deserts – but instead thrill-seekers are using them to fill balloons with dangerous nitrous oxide before inhaling the fumes.
The gas slows down brain function and is said to induce euphoria and laughter – hence its nicknames 'hippy crack' and 'laughing gas'.
But the craze is no laughing matter as the gas can also cause hallucinations, asphyxiation, nerve damage and even death.
Government data revealed that eight people died from inhaling the gas in the UK in 2016 - double the previous year.
The Woodhouse great-grandmother warned it could only be a matter of time before the craze claims a life in Sheffield.
Her warning has been echoed by the authorities, who issued a public health alert on the dangers of inhaling nitrous oxide today.
The 81-year-old, who did not want to be named, said: "I couldn't believe how many there were. I have seen them doing it loads of times.
"It has caused so many deaths. It is very dangerous, and it could only be a matter of time before someone else dies."
She conducted her own litter pick to remove the canisters and reported it to police.
This is not the first time they have been found either.
Police said nearly 70 of the empty canisters were found around the city and in Rotherham, including some that had been stolen from a hospital, in 2015.
And in June last year, officers found another stash in Rotherham.
In a statement, South Yorkshire Police said they have introduced extra patrols after it is believed “the canisters were discarded after the fumes inside had been inhaled by teenagers. ”
Inspector Dave Struggles said: “Not only is it illegal to supply these gas canisters for inhalation, but it is also very dangerous. It lowers the oxygen in the brain and can cause serious damage.”
Sheffield City Council also warned about the dangers and, citing advice from the Talk to Frank website, said people who take it “risk falling unconscious and/or suffocating from the lack of oxygen. People have died this way.”
Dr Anthony Gore, Sheffield GP and clinical lead for delivery – care outside of hospital at Sheffield Clinical Commissioning Group, said: “Nitrous oxide is a depressant, which means it slows down your brain and your body’s responses. By taking nitrous oxide, you can pass out or suffocate from a lack of oxygen in your body.
“Sadly, people have died this way. We really recommend thinking twice before taking nitrous oxide or any other harmful substance.”