NSW Health Minister Ryan Park has pleaded with people not to buy vapes, just a day after a Sydney man became the first person in Australia to be charged with the supply of vape liquids laced with potentially lethal opioids.

NSW Police arrested the 20-year-old man after officers seized nitazene, a safe, vape hardware, imitation firearms, and about $7000 in cash at a property in Revesby on August 1.

After opening the safe on August 4, police found a further 1.8kg of nitazene, taking the total seizure to 2.1kg.

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Nitazene is a highly potent synthetic opioid which is potentially more dangerous than fentanyl.

Speaking about the seizure on Sunrise on Thursday, Park issued an emotional plea for people to not buy illegal vapes.

“I am really concerned both as a policymaker and a legislator and health minister but also, importantly, as a dad of a 15-year-old,” Park told host Matt Shirvington.

“I cannot believe this has taken place.

“This highlights the risks but it also highlights why need to take action in relation to vapes and illegal tobacco.

“We can’t have a situation where this is available, particularly to young children, across NSW.

“My message is simple, you don’t know what is in it, you don’t know who has made it and usually don’t know if it is linked to criminal activity. Therefore, it is likely to have a substance that is extremely dangerous.”

Park stressed how toxic nitazene is to the human body. It is largely understood to be more dangerous than fentanyl.

In the US, synthetic opioids such as fentanyl contribute to nearly 70 per cent of overdose deaths.

“It is extremely dangerous. How it reacts in one person’s body compared to another is completely different,” Park said.

“It can have catastrophic outcomes, and it can kill people extremely quickly. This is designed to get a generation hooked on this type of illicit opioid.

“That is extremely concerning from a NSW Health perspective but also, from the dad of a teenager, I cannot begin to imagine how scared (parents are) around marketing of vapes and illegal tobacco.

“This will send a real shudder through many families when they hear about this.”

Shirvington pressed the minister on the source of the illegal drug, asking whether it was made in a backyard or sourced from overseas.

“It is a combination,” Park said.

“No doubt what they are trying to do is bring it into the country at a point and then what we see is the ability of backyard labs to manufacture this type of substance.

“That is why this is extremely concerning.

“We cannot have a situation like what we see in parts of the US, where this is widespread and having catastrophic outcomes in communities in the country.

“This is the last thing we want to see coming onto NSW and Sydney streets.”

Park also championed harsher penalties for sellers.

“We have introduced legislation that will see potentially people going to jail for seven years and fines of up to $1.5 million for the sale of illegal tobacco or vapes,” Park said.

“As well as the ability to shut down a premise, not to shut down the component that is selling these products but shut down the business for a period of up to three months and then, if possible and if ongoing, the court can issue even longer shutdown orders.”