Student, 24, killed by long-term nitrous oxide use 'got through 200 canisters a day'
![Student, 24, killed by long-term nitrous oxide use 'got through 200 canisters a day'](https://i2-prod.mirror.co.uk/incoming/article32557940.ece/ALTERNATES/s615/1_PAY-Student-death-due-to-laughing-gas-abuse.jpg)
Business student Ellen Mercer, 24, told her boyfriend not to call an ambulance as it “kills her buzz” when she began suffering leg and back pain - she was rushed to hospital but died two days later