E-nose knows a smoker

Some people tell their doctors that they are non-smokers in a bid to get cheaper life insurance. But an electronic nose could scupper such deception.

A team led by Paul Thomas at the University of New South Wales in Sydney, Australia, tweaked a commercially available e-nose so that it would detect the volatile organic compounds (VOCs) in the breath of a person who had smoked a cigarette.

The e-nose uses an array of 32 sensors whose electrical resistance changes as different VOCs are detected. The resultant "smellprint" correctly identified 37 out of 39 volunteers as either smokers or non-smokers.

The team conclude that e-noses could quickly and reliably reveal smokers without the need for a blood or urine test. Currently, the carbon monoxide content of exhaled breath is used to measure smoking activity. But this technique picks up a smoker for only a few hours after their last cigarette, and is prone to error: it cannot tell if carbon monoxide in the breath came from other sources such as traffic exhaust fumes.