Scientists at three European universities have developed a chip that can 'sniff' dangerous gases, paving the way for credit card-sized sensing devices.

The prototype, which integrates three different kinds of gas sensors on a single chip, could be used to detect organic solvents leaking from containers, or for safety monitoring in the chemical industry, the researchers said in an article published in last week's edition of the science journal Nature.

The sensor technology is implemented on a single 7x7mm silicon chip, making it suitable for low-cost mass production using facilities which already exist for microelectronics fabrication, said a statement from the Swiss Federal Institute of Technology Zurich, which worked on the project alongside the universities of Tübingen, Germany, and Bologna, Italy.

The prototype is part of a project to develop a palm-sized gas analysis device, the Institute said.