The distraught friend of a Christchurch teenager who died after huffing butane watched in horror as members of the public tried unsuccessfully to revive the 17-year-old at a suburban park.

Poihaere Eru, known by her friends as Pumbah, was declared dead shortly after arriving at hospital on Saturday.

Police revealed yesterday they found 16 cans of butane at Hansons Reserve in Upper Riccarton, where Eru had been huffing with two friends aged 14 and 16.

Detective Sergeant Craig Farrant said the young women might have bought more cans than those recovered, each of which contained about 500ml of butane gas. They were believed to have been bought at a nearby shop.

"There is evidence they had significantly more over the preceding 24-hour period," Farrant said.

The death comes weeks after Chief Coroner Neil MacLean launched a review into huffing. This followed the death in May of Christchurch 12-year-old Darius Claxton and the serious injuries suffered last month by two Mosgiel teenagers.

Police have started an inquiry into the sale of butane as a result of Eru's death.

Emergency services were called to the park, on the corner of Hansons Lane and Haynes Ave, about 4.40pm on Saturday.

Farrant said it appeared the three girls had been huffing the butane in some flax bushes.

After Eru collapsed, one of the girls panicked and fled the park.

The other became "very hysterical" and attracted the attention of two members of public.

A man and a woman attempted CPR until St John Ambulance arrived, Farrant said.

Police took both friends for medical treatment as a precaution.

The Press understands Eru was a former Riccarton High School pupil.

Tributes were posted on her Facebook page.

One friend paid tribute to Eru as "an amazing girl always smiling".

Principal Phil Holstein said her family were devastated and the school was supporting them and the wider community.

Farrant said shop owners had a "moral obligation" to regulate solvent sales to teenagers who were clearly not buying it "to go camping".

He said the death was "a tragic accident" and "a waste of life".

"We secure spray paint, why can't we secure butane? Because it's killing our kids."

National Addiction Centre director Doug Sellman said butane was "not far away from heroin in terms of the risk of overdose".

"Many young people underestimate the dangers of this class of drugs. It is the same class of depressive drugs Michael Jackson died from."

Butane and other solvents caused users to lose inhibitions.

However, like alcohol, solvents had a "depressive, anaesthetic impact" on the brain, quickly making users feel tired.

Sellman said solvents poisoned the respiratory system, affecting breathing and could increase heart rate. A surge of adrenaline could cause that beating to become irregular and stop the heart.

Between 2007 and 2011 there were 28 huffing-related deaths in New Zealand.

- © Fairfax NZ News