"I'd be quite concerned if retailers were dropping prices to clear products as a result of the law coming in - and they need to be responsible because these products can and do cause harm.
"Now that we know much more about the harm that is being caused, you would view it as being reckless," Mr McClay said.
Health workers were coming to him each day with new horror stories, including an 11-year-old who developed addiction problems.
"The sooner this dangerous muck is out of our dairies and corner stores the better," Mr McClay said.
The Ministry of Health was working with police to develop a system allowing retailers to safely dispose of them.
Mr McClay was satisfied the new law would provide a strong framework, giving councils new powers to restrict sales in their communities, and forcing manufacturers to prove their products were safe.
Retailers who flagrantly flouted the new law could be handed prison sentences or fines of up to half a million dollars.
Psychoactive drug advocacy group The Star Trust was meanwhile making retailers aware they could return products to distributors with full refunds under industry-wide amnesty.
Of 13 Auckland dairies surveyed by the Herald in K Road, Sandringham, Pt Chevalier and Ponsonby yesterday, more than half said they no longer stocked synthetic cannabis.
Crackdown countdown
*The Psychoactive Substances Bill is expected to pass its third and final reading this Thursday and come into force the week after.
*It will see all legal highs removed from dairies and non-specialist shops and ban the sale to, and possession and consumption by, people under 18.
*The law will also force manufacturers to prove their products are safe and list all ingredients on the label, and gives councils new powers to restrict sales in their communities.
Town unites to banish party drugs from shelves
Known for its crystal-clear Blue Springs, Putaruru today becomes famous for something else - saying no to legal highs.
The South Waikato township is believed to be the first community in the country to take a unified stand against the products, after all local retailers chose to stop stocking them.
Sergeant Jason Shailer, who set up a meeting where shopkeepers agreed to a ban, said synthetic cannabis had added a nasty dynamic to crime in his community.
Even while talking to the Herald outside the town police station yesterday, constables were inside dealing with the latest case - a man who had badly beaten his partner.
"He was really high on the product, and was really committing something serious. I doubt whether that would have happened had it not been around."
Staff at Putaruru-Tirau Family Doctors were encountering its ugly effects as frequently as twice a day.
"They [users] are angry, they're demanding, they use very foul language, and they're aggressive ... sometimes thumping on the counter, kicking and slamming the doors. They seem very agitated," practice manager Trish Cole said.
GP Dr Tom Holmes said these patients sometimes arrived sweating profusely, suffering heart palpitations, "and obviously feeling very uncomfortable".
Local retailer Sid Patel said the products were big sellers, but admitted he had been selfish by not considering the harm they caused.
Mr Shailer said uniting the town had not been hard, and urged other communities to follow suit.
"I think it's worth asking the question. It's worth having a go."
Inspector Rob Duindam, of the Police National Crime Group, congratulated the town.
"There have been other local store owners in towns around New Zealand who have taken a similar stand, and police and communities have been working together to encourage stores to get synthetic drugs off their shelves."
