A Sydney man has become the first in Australia to be charged with the alleged 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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Detective Superintendent John Watson from the drug and firearms squad described the drug find as “deeply” concerning.

“Nitazenes are highly addictive, incredibly potent and can be lethal,” he said.

“By lacing vape liquid with these synthetic opioids, suppliers are deliberately creating dependency — hooking users to ensure repeat business.”

Watson also highlighted the “disturbing evolution” of the illicit drug trade.

“It’s calculated, dangerous and entirely profit-driven,” he said.

NSW Health chief addiction medicine specialist Dr Hester Wilson warned of the serious harm these drugs can cause.

“We want to remind the community of the dangers of synthetic opioids such as nitazenes, which can be stronger than fentanyl,” Wilson said.

The man has been refused bail and is due to appear in Burwood Local Court on September 25.