BioEd Online

A US company this week got the green light to implant tiny chips in people's arms in order to instantly access their medical records. The move highlights how this unassuming technology is now sweeping into everyday use.

The VeriChip, made by Applied Digital Solutions in Delray Beach, Florida, is the size of grain of rice and is injected under a patient's skin. On 13 October, the company announced that they had received approval from the Food and Drug Administration to market them in the United States.

The chips are a type of radio-frequency identification (RFID) tag, and each contains a computer chip encoded with a unique identification number and a tiny antenna. To read the tag, a scanner that emits radio waves is waved over the chip. This is detected by the antenna, which generates a tiny electrical current in the chip and powers the tag into beaming back a radio signal that reveals the ID number.

Applied Digital Solutions says that chips rooted in the skin could be used to pull up a patient's personal and medical records from a secure database. This could prove useful when, for example, someone is unconscious or has numerous records at different clinics that must be pulled together in an emergency.

But privacy advocates argue that tagged bracelets or cards carrying medical information are just as effective as an implanted chip. They warn that the chips might ultimately find a use to compulsorily tag and track prisoners or visitors to a foreign country. "They've crossed a line by placing it under people's skin," says Marc Rotenberg of the Electronic Privacy Information Center, a civil liberties group in Washington DC.

Chip invasion

RFID tags have been around for over 50 years, although many of them are larger, battery-powered and actively transmit data carried on their chips.

Over the last decade, smaller, cheaper 'passive' chips have been developed that only release information when scanned - and these chips are now poised to invade many aspects of our lives. "The technology is very much coming to the forefront," says Dan Mullen, president of Association for Automatic Identification and Mobility, a trade group based in Warrendale, Pennsylvania.

Most people are already using RFID tags unawares: in security badges that allow access to buildings, or in keys that communicate with a car to allow only the driver in. Many companies are also starting to use the chips to track goods shipped from manufacturers to their destination, helping them keep precise track of where items are and avoid them being mislaid in warehouses.

RFID tags are already routinely implanted in pets, so they can be identified if lost. But Applied Digital Solutions say that VeriChip is the first chip designed for use in people. Some people have already been tagged; the Attorney General of Mexico and some of his staff had chips implanted to limit access to a secure room.

The company needed approval from the FDA in order to market the chips for medical uses. But Mullen questions whether patients will be lining up just yet to have the device shot under their skin. "I'd be surprised if it's a very palatable thing," he says.