SALES of a potentially deadly gas to people under 18 is on the increase - despite the threat of legal action - trading standards officers warned yesterday.

Retailers were banned from selling butane gas lighter refills to minors following a spate of deaths involving teenagers sniffing the substance for kicks.

Nationally in 2002, there were 63 deaths linked to solvent abuse, with 15 of those directly attributable to toxic shock caused by butane inhalation from lighter refill cans.

North Yorkshire trading standards officers are responsible for enforcing legislation relating to the sale of age-restricted products and test purchases are made at premises that sell cans of butane.

A spokesman said that although many traders took a responsible attitude when the product was requested by teenagers, an increasing number were failing to ask for proof of age before agreeing to sell it.

Trading standards are investigating numerous cases where retailers in the county have sold butane to children - some as young as 13.

The investigations follow a prosecution at Harrogate Magistrates' Court, where a Ripon retailer was fined £200 with £250 costs after pleading guilty to selling a can of butane to a 14-year-old boy.

Councillor Helen Swiers, executive member with responsibility for trading standards for North Yorkshire County Council, said: "As well as causing sudden death among youngsters, abuse of this product can inflict lasting damage on the liver and kidneys.

"Any retailer should question themselves as to why youngsters should need this product, particularly when the legal age for tobacco sales rises to 18 this October.

"Retailers should play safe and I would support the Challenge 21 agenda, whereby anyone looking to be under that age is asked for proof of age when buying age-restricted products of any kind."

He added that if any retailers were unsure about the age limits applicable to the various age-restricted products, or wanted advice about proof of age cards, they should contact trading standards on 08454-04-05-06.

Butane was once described as the "fuel of the forgotten deaths" by New Scientist magazine - because deaths arising from its misuse went generally unnoticed compared with those caused by drug abuse, it said.

Nationwide campaigns for stricter controls on the sale of butane were led by MPs and local authorities, and there were drives to raise awareness among shop workers