"This is the worst possible outcome for them and the wider community."
He said police investigating the teenager's death would look at the origin of drugs found in his possession and if they were linked to those taken by the two other people in hospital.
At the Adelaide event, six people were evicted, 34 were refused entry after being detected with drugs, two were detained for drunken behaviour, 23 were issued with drug diversions and 34 pills were seized.
At Melbourne's Stereosonic event also on Saturday, 60 people were arrested for drug-related offences.
The festival deaths have sparked calls for drug testing services to be allowed at Australian events so users know what they are taking.
The mother of a Melbourne man who died after taking drugs at a Victorian music festival in 2012 has collected 33,000 signatures so far in her Change.org campaign for drug testing services at festivals.
"Until we wise up and accept the reality that drug testing services are the only way forward, kids like my son and the most recent man in Adelaide - another mum's poor son - will continue to die," Andriana Buccianti said.
Superintendent De Candia said such services were a matter for governments.
"If you want to be 100 per cent certain in relation to illicit drugs, if you want to be safe, the message is clear - don't take them," he said.
South Australian independent senator Nick Xenophon wanted to know what duty of care the organisers felt they had to the young people at the festival.
"I have heard from people whose children went to this event ... that there were people snorting drugs off people's foreheads ... that there were so many people that were completely out of it," he said.
Prime Minister Malcolm Turnbull sent his condolences to the Adelaide man's family, after he announced A$300 million in new funding for treatment, prevention and education to tackle the ice scourge.
SA Opposition Leader Steven Marshall said pill testing would send a dangerous message to young people that drug taking was safe when it wasn't under any circumstances.
- AAP