He says nitrous oxide - or laughing gas - has become incredibly popular with clubbers and festival-goers.
Normally used as a propellant in whipped cream canisters, inhaling the nitrous oxide capsules can bring on two minutes of giggling, euphoria and even hallucinations.
"We attend festivals each year to keep tabs on what people are taking," he says. "Last year the fields at Glastonbury were littered with nitrous oxide capsules.
"While the substance itself is not that dangerous, it's the stupid things people do while under the influence that's of concern. For example, there was a case of someone putting a condom over their head and suffocating."
Statistics show that four people died as a direct result of using laughing gas in 2007 and figures for 2008 are predicted to be higher. (full article here:
http://www.newsoftheworld.co.uk/fabulou ... ivals.html