"What we're seeing around the world is a whole lot of new chemicals being cooked up designed to mimic drugs like LSD and ecstasy," he said.
When a sample was not kosher, it was most likely to be a cathinone, a new family of drugs commonly known as "bath salts".
Both KnowYourStuffNZ and the Drug Foundation are calling for the law to be changed to allow for legal drug checking at festivals. KnowYourStuffNZ says it has the ability to test drugs using a spectrometer, a practice that happens at festivals in some European countries. Under current law, someone testing drugs can be charged with possession.
KnowYourStuffNZ reckons more people would ditch whatever drug they had bought if it was found to be different.
Hamish Pinkham, the founder and director of Gisborne festival Rhythm and Vines, says he doesn't want drug testing at the event.
"Unfortunately, drug use is going to happen and it can be prevalent and as organisers, it's our role to do our utmost to prevent that," he says.
"But I think testing is condoning drug use in some respects. We're not the fun police and while we absolutely don't condone drugs ... people don't want to feel like they're being scrutinised or tested."
KnowYourStuffNZ claims festival organisers are "clamouring for drug checking services but are fearful of the legal risks", but Pinkham isn't one.
"We've got our rules and people need to adhere to them and if they break them they do so at their own risk. We work really closely with the authorities to maintain our drug-free stance. There are bag searches and we have emergency services on hand if there's any trouble."
He says drug use hasn't been a big issue at R and V over the past few years, and when problems have arisen, they've been dealt with calmly.
"There was an issue last year and we worked with the police to bust one of the tents that was operating as a drugs sales point. So we're always vigilant and on the lookout for that sort of thing."
Annie* has been a frequent festival-goer over the past 10 years or so. She says she's never been too afraid of getting high.
"What drugs have I done at festivals? Acid was a big one for awhile and the go-to. I've also done MDMA, weed and cocaine," she says.
"Mostly, I would buy drugs at festivals because I was too scared to smuggle them past security. I have a guilty face, so I don't get away with much. You know you're going to get them there, so I would rely on that."
She is concerned about what she's buying, but not too much.
"I guess you just risk it and hope you're not going to get shafted. But with drugs, no matter where you get them, there's always a risk."
Annie has had a few rough experiences and bad trips, but "also a lot of fun ones".
She's unsure about the idea of testing.
"I guess it makes sense and could work, especially as I'm not against drugs and people should be able to make their own decisions," she says.
"But I'm really not sure how it would effectively work as there are thousands of people at festivals. I also wouldn't want a group or the authorities actively going after people and putting a dampener on things."
She says she's also feel nervous about showing strangers, possibly in some sort of uniform, drugs she'd bought.
"I'm personally far more concerned about people who drink and get wasted."
Late last year, the police said the use of drug-checking kits was something for event organisers to worry about.
Associate Health Minister Peter Dunne said he was open to the idea.
"It's just an idea that makes sense. We have a drug policy that is based on innovation, compassion and proportion as its core principle," he said.
"To be perfectly honest, I think the reason is that it's just a little bit difficult in the sense that we have a law that prohibits the use of illicit drugs ... everyone is on the same page so what we probably need is an approach from the Drug Foundation or a festival organiser or someone to say, 'Look, how can we actually do this?'"
*Annie is not the woman's real name - she doesn't want her mum finding out about her relatively excessive history of drug use.
