Shopkeepers are being urged to be vigilant over the sale of potentially lethal butane fuel after the death of a man addicted to sniffing the vapour.

Jobless Adrian Downs, who was also an alcoholic, was found dead at his home in Harcourt Way, Wantage, among hundreds of discarded cans.

An inquest in Oxford heard Mr Downs, 47, bought lighter refills in packs of a dozen, and that one large canister, which might take a 20-a-day smoker a year to use up, lasted him just an hour in pursuit of his habit.

The dead man's sister-in-law, Sylvia Downs, of Wessex Road, Didcot, said his family had exhausted every avenue in a bid to get help for him.

"We tried every aid abuse organisation we could think of, and they said that because he was over 17, there was nothing they could do," she said. "At the present time, there is not a law forbidding shops to sell large amounts of butane gas at any one time to people over 17 years old. They are often sold in packs of six, and Adrian used to purchase 12 at a time.

"If it was only possible to purchase one can at a time, it would have made it more difficult for him to pursue his addiction, and his subsequent death could possibly have been avoided."

Mrs Downs found his body on October 28 when she called with a relative, Patricia Clitheroe. As well as the canisters, they found cans of strong lager and an empty litre bottle of vodka.

Earlier, Mrs Downs told the inquest that he had been a binge drinker who had been told by doctors that unless he stopped drinking it would kill him. Last year, she and her husband discovered he was also sniffing butane, and on one occasion, found him at home almost unconscious with about 200 empty cans in the house.

After a fortnight's treatment at Littlemore Hospital in August, he had returned home and gone straight out to buy gas without even unpacking his bags, she said.

The Oxfordshire coroner, Nicholas Gardiner, who heard that Mr Downs had died from the paracetamol overdose, said he had no choice but to record an open verdict.