More than 4,000 Swedes are being implanted with a microchip that contains details about their identity.

The miniature technology bypasses the need for cash, tickets, access cards and even social media.

BioHax International is the market leader in the innovate industry and has captured public imagination since it was started five years ago by Jowan Osterlund, a former professional body piercer.

Some people argue the conveniences gained from the procedure by so-called 'body-hackers' do not outweigh the risks to their private data.

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RFID implants (pictured) use Near Field Communication technology which is the same as in contactless credit cards or mobile payments. It is roughly the the same size as a grain of rice and the procedure costs about $180 (£140)

In June 2017, SJ Rail, the Swedish train operator, announced that around 100 people were using microchips to pay for their journey.

Commuters with a microchip in their hand are able to have their ticket loaded directly onto the device.

The train conductor can then read the chip with a smartphone to confirm the passenger has paid for their journey.

This was one of the most widespread and mainstream uses of the technology and has seen it be adopted by a plethora of forward-thinking companies.

Microchipping has even been adopted by professional social media platform LinkedI.

Szilvia Varszegi, 28, said the chip 'basically solves my problems'.

Touching an event attendee's smartphone will allow the information to be transferred without the need for typing.

BioHax International is the market leader in the innovate industry and has captured public imagination since it was started five years ago by Jowan Osterlund (pictured), a former professional body piercer

HOW DO MICROCHIPS IMPLANTED UNDER HUMAN SKIN WORK? Several Swedish firms are implanting their employees with microchips under their skin which can be used to replace keys, credit cards and train tickets. The small implants use Near Field Communication (NFC) technology, the same as in contactless credit cards or mobile payments. When activated by a reader a few centimetres (inches) away, a small amount of data flows between the two devices via electromagnetic waves. The implants are 'passive,' meaning they contain information that other devices can read, but cannot read information themselves. Near Field Communication (NFC) as contactless bank cards, and London's oyster cards, suggesting it could be used further afield one day. Advertisement

Ms Varszegi said: 'When another phone reads the chip, they see the [link] and they can open it in the phone browser.'

The futuristic project has not been without its hiccups, and has also generated concerns over passenger privacy.

When it was launched lat year, one flaw in the system meant that rail staff would sometimes be shown a passenger's LinkedIn profile instead of their ticket information.

While the scheme is currently only available in Sweden, the country's travel system uses the same Near Field Communication (NFC) as contactless bank cards, and London's oyster cards, suggesting it could be used further afield one day.

The electronic tags are around the size of a grain of rice and are implanted via a syringe into the back of the hand - often above the thumb.

Several companies in Sweden already offer the service to their employees - often for free - to help them quickly enter the building or pay for cafeteria food.

Jowan Ãsterlund (right) is a tattooist and body piercing specialist turned biohacker, who has chipped most people in the world. An electronic implant is inserted under the skin to replace keys, business cards and train tickets

WHY DID A SWEDISH FIRM INJECT ITS EMPLOYEES WITH MICROCHIPS? Swedish firm Epicenter hit the headlines in April for offering RFID implants to its employees. The Startup offers workers microchips the size of grains of rice that function as swipe cards, to open doors, operate printers, or buy smoothies with a wave of the hand. The injections have become so popular that workers at Epicenter hold parties for those willing to get implanted. But, experts say the ethical dilemmas will become bigger the more sophisticated the microchips become. Self-described 'body hacker' Jowan Osterlund from Biohax Sweden, holds a small microchip implant, similar to those implanted into workers at the Epicenter digital innovation business centre during a party at the co-working space in central Stockholm The technology in itself is not new. Such chips are used as virtual collar plates for pets. Companies use them to track deliveries, but it's never been used to tag employees on a broad scale before. Epicenter and a handful of other companies are the first to make chip implants broadly available. And as with most new technologies, it raises security and privacy issues. While biologically safe, the data generated by the chips can show how often an employee comes to work or what they buy. Unlike company swipe cards or smartphones, which can generate the same data, a person cannot easily separate themselves from the chip. Advertisement

The implants were first used in 2015 - initially confidentially - before they were later rolled out.

While concerns have been raised over potential personal data violations, many Swedes are favouring convenience over their privacy.

Twenty-eight-year-old Ulrika Celsing had a microchip injected into her hand that allows her to enter her workplace without needing her security card.

She said she is not concerned over the potential hacking of the data stored in the chip.

'I don't think our current technology is enough to get chip hacked,' she told AFP.

'But I may think about this again in the future. I could always take it out then.'

To enter her workplace, the media agency Mindshare, Ms Celsing simply waves her hand on a small box and types in a code before the doors open.

'It was fun to try something new and to see what one could use it for to make life easier in the future,' she said.

Mircrochip implants are not new in Sweden, and thousands already have them, using the devices to swipe in and out of the office, and even pay for food.

Swedish nationals can embed microchips under the skin on the back of a person's hand. SJ Rail, a Swedish rail operator, uses the chips to allow customers to pay for tickets (pictured)

Swedish citizens have long accepted the sharing of their personal details.

The country has a track record for sharing of personal information, which may have helped ease the microchip's acceptance.

Personal details in the Scandinavian state are registered by the social security system, with other administrative bodies.

It is possible for people to find out each others' salaries through a quick phone call to the tax authority.

Mr Libberton said: 'In Sweden, people are very comfortable with technology and I would say there is less resistance to new technology here than in most other places.'

Some experts have urged caution with the burgeoning microchipping scene.

Ben Libberton, a microbiologist at the MAX IV Laboratory in the Swedish city of Lund which provides X-rays for research, told AFP: 'At the moment, the data collected and shared by implants is small, but it's likely that this will increase.

'The more data is stored in a single place as could happen with a chip, the more risk it could be used against us.

'If a chip can one day detect a medical problem, who finds out and when?'

He added that the chip implants could cause 'infections or reactions of the immune system'.