Transport authorities in New South Wales have threatened to deactivate an Opal card that has been implanted in a Sydney man's hand.

Sydney bio-hacker Meow-Ludo Disco Gamma Meow-Meow — his actual name — had the near-field communication (NFC) chip from an Opal card cut out and encased in a bio-compatible plastic.

The device was then implanted under the skin in his left hand, allowing him to "tap on" by waving his hand over the readers on the city's ferries, buses and trains.

Loading

In a statement, Transport for NSW said it did not encourage such experimentation.

"Transport for NSW does not support the tampering or damaging of Opal Cards, which would be a breach of the terms of use," they said.

Transport authorities said if the scientist is discovered using his implanted card, it could be deactivated.

"Customers that are caught tampering with their Opal card may have their card cancelled," they said.

Under Opal's terms of use, transit officers can confiscate cards, but in this case it is impossible as it is under his skin.

The implanted Opal card is not as sensitive as traditional cards and can require several swipes due to modifications including a shorter antenna.

"Changing the physical attributes of the card may impact the reliability of the Opal card," Transport for NSW said.

Bio-hacker 'not super stressed'

Mr Meow-Meow earlier said he hoped authorities would welcome his experimentation, because he believed they were open to innovation.

"Hopefully they react favourably and encourage this," he told followers in a Facebook live event.

Authorities say it is actually a breach of Opal's terms of service to have the implant. ( ABC News: Nick Dole )

"I can walk out of my house, forget my wallet, forget my phone and everything and I'm still going to able to interact with technology."

He acknowledged his chip might become obsolete in the coming years, but said he was "not super stressed" about it.

"Opal will be superseded in the next two to four years and I think [Melbourne's] myki will too."

Mr Meow-Meow's Opal device was implanted by a piercing expert who could manage the risk of infection.

The bio-hacker warned others not to do the same without careful research and expertise.

He predicted NFC implants would grow in popularity and that companies could use them to give clients a more convenient experience.

"They're going to say 'Hey, do you want to give us your unique ID and then we'll put that on and that will verify you?'" he said.