An idea used as an April Fool's joke could soon be helping save lives.
The sensor could be used in portable travel alarms
Siemens is developing small sensors that can detect a wide variety of odours, opening the door to portable devices that can spot fires or health problems early.
Doctors have long known that trace elements in breath can give clues to a person's underlying health.
The tiny detectors could even be used in cars to stop people taking to the road when drunk.
Dr Max Fleischer and colleagues at Siemens' Corporate Technology division in Munich have been developing the technology behind the sensitive chips.
Dr Fleischer said the work on the sensors won a higher profile after the Siemens PR department issued a April Fool's press release saying the company was working on a mobile phone that could detect how drunk its owner was.
"They didn't know that we were really working on the technology to realise that," he told BBC Radio Five Live.
Some unconfirmed reports have even suggested that the device could be used to monitor bad breath.
The sensors produced by Dr Fleischer and colleagues are about 1 mm square and can be tuned to react to many different gases. The sensors can spot the target gas often when it is present in tiny quantities.
If a gas is present in the air wafted across the detector, it reacts with the silicon substrate of the sensor causing a reaction that can be electronically measured.
Once exposed to ambient air the sensor regenerates ready to be used again.
The sensors small size and power demands mean that they could be used in portable devices, said Dr Fleischer.
He said such portable devices could find a role in healthcare, fire-fighting or to police consumer behaviour.
Doctors have known for a long time that different conditions show themselves in breath long before they become more obvious.
For instance it is known that asthma sufferers, those with cystic fibrosis and some forms of cancer breathe out chemical markers of their condition.
The exhalations of lung cancer victims are known to have higher ethane concentrations than those without the disease.
The hardware could also help asthma sufferers who also breathe out telltale chemicals.
"The sensor will detect traces of special gases and give an early warning to people that an asthma attack might occur in the next three to four hours," he said.
Other groups of researchers are already producing handheld gadgets that help medical staff diagnose problems using exhalations.
In fire-fighting, the sensors could give warnings much earlier than existing detectors and alarms.
The sensor can spot fires early
"Present day fire detectors measure the temperature or the smoke density," said Dr Fleischer.
"Our sensor gives a warning before the fire really breaks out," he said. "Just like the human nose, it can sense early on if something is smouldering or starting to burn."
Dr Fleischer speculated that the sensors could also find their way into cars to stop people driving drunk.
"This car might decide that the driver is drunk and, for example, refuse to start the engine," he said.
He stressed that such a system would have to be voluntary and not imposed on people.
"It would depend on whether people really want to use it," he said.
Dr Fleischer speculated that in the future travellers might well carry a portable alarm with them that can detect a variety of noxious substances including ozone and carbon monoxide.