Young people are putting themselves at risk by inhaling laughing gas nitrous oxide in the latest “legal high” trend to hit the Ilkley area, police have warned.

Police are warning parents to be on the lookout for small silver canisters of the gas, which is used as an anaesthetic in dentistry.

Nitrous oxide is also used in the catering industry to produce whipped cream, and it is believed canisters found in the area could have been bought legally from catering industry suppliers.

Inspector Sue Sanderson, of Wharfedale and Craven Neighbourhood Policing Team, said: “The problem is they’re being purchased and young people are using them them as a legal high. The concentrations of N2O used in the medical profession are carefully controlled and mixed with the right amount of oxygen to make it safe. By comparison, this is a much higher concentration. It could have detrimental effects.”

Long-term effects on health are not fully known, but inhaling the gas carries a risk of asphyxiation, lung damage and mistakenly inhaling other propellants or harmful substances.

The quest for legal highs has seen a rise in the use of various substances in recent years. Police in Ilkley were among the first to warn last year about the use of mephedrone, also known as MCAT, which has since been classified as a Class B controlled substance.