Medical-grade gas could go on sale in vending machines at some of Colchester's premier nightspots.

The idea of selling pure filtered oxygen in nightclubs is now being looked at by the Hippodrome and Chicago Rock Cafe owners Luminar Leisure.

Inhaling the pure gas gives users a sense of euphoria, alertness and heightened senses.

But the idea on Friday sparked fears among health experts who said one of the effects of using pure oxygen can be people stopping breathing.

Oxygen is already sold in some gyms and health clubs in the country and can be found on sale in bars in America.

But Luminar Leisure now want to see if the gas will be popular in its nightclubs. They are now experimenting in one of its nightclubs but the sales experiment looks set to be tried out at more venues.

A spokeswoman for the firm said other test venues had not yet been decided.

Steve Dennis, director of Luminar Leisure, said: "If the machine gives a worthwhile profit margin and produces enthusiastic and happy customers whilst not harming health or generating anti-social behaviour and there is a demand, we will meet it."

A spokesman for Essex Rivers Heathcare Trust said oxygen was used in hospitals for people with breathing problems such as asthma or eczema and also for people immediately after operations.

But the spokesman added: "Potentially it can be dangerous because if you have been given extra oxygen it reduces the body's carbon dioxide levels - you can stop breathing."

By Laurence Cawley

Reporter's e-mail: laurence_cawley@thisisessex.co.uk

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