Associate Health Minister Peter Dunne announced yesterday a temporary class drug notice had been issued in respect of two substances found in tested samples of K2.
That effectively means from May 9, those importing, manufacturing, selling or supplying the substances face a penalty of up to eight years' imprisonment.
Mr Dunne told the Otago Daily Times he had a message for those selling the product - ''Stop''.
''Stop for a number of reasons. You are potentially now committing a criminal offence that could have you off to jail, so think about that for your business. And, secondly, you are selling a product that is dangerous to people's health.
''Show some responsibility, some sense of commitment to your community. Listen to the voice telling you to stop it and do so.''
The ban on BB-22 and 5F-AKB48 brings to 35 the number of substances prohibited under the temporary notices, leading to more than 50 products being removed from retailers' shelves.
Mr Dunne was not concerned by how long testing could take as ''it has got to be done properly''.
He acknowledged authorities had been playing a ''cat and mouse'' game with distributors, but new legislation set to be introduced as early as mid-July would end that.
Submissions on the Psychoactive Substance Bill close today, and the Bill was being watched closely by other countries, including the United Kingdom, Australia, United States, France, Ireland, Germany and Canada.
''We are the only country that said 'Let's turn this on its head, and put the onus right back on the manufacturers ...'
''They bear the cost of the testing process and have to be the one in the gun because, after all, they are the ones producing this stuff.''
In the interim, he was supportive of boycotts of stores that sold the product.
''It is good that communities speak up and effectively remind them of the risk that they run, not just legal but the threats to public health.''
Toxicologist Leo Schep said the ban was likely to ''take the pressure off'' in regards to calls to the Dunedin-based National Poisons Centre.
However, he warned any synthetic cannabis product could contain any one of a number of different substances from month to month.
Senior Sergeant Chris McLellan, of Dunedin, who also welcomed news of the K2 ban, said police were likely to visit sellers to make sure it was off the shelves, as they did with other banned products.
