Breath test could identify trapped disaster victims
LEICESTER, UNITED KINGDOM – People trapped under large scale urban rubble after a disaster could be rescued by searching for the chemicals in their breath, according to research findings published in The Journal of Breath Research.
Scientists found in a mock-up of a collapsed building using volunteers that molecules of acetone and ammonia in the participants’ breath were easily detected through the simulated rubble.
Their findings are being used to develop an “electronic sniffer dog” that could search disaster sites for survivors, BBC News reported.
A demonstration device developed under the Second Generation Locator for Urban Search and Rescue (SLG) project has already been produced by one of the research collaborators. It is intended to supplement rather than replace the search-and-rescue dogs currently employed at disaster sites.
“Dogs are fantastic but they don’t work for very long, and they undergo injury and suffering as a result of their work in a search and rescue environment,” said Paul Thomas, the Loughborough University chemist who led the research.
“We don’t know what the dogs detect. The SLG about producing better sensors and systems that can find people,” Professor Thomas told BBC News.
“We need to try and define in scientific terms what a ‘signs of life detector’ would need to respond to. But what starts from a human and travels through buildings may not be what gets to the end of the building – there’s a whole range of materials that it has to pass over and through.”
To determine what chemicals future detector technology should be sensitive to, Professor Thomas and his colleagues carried out a series of experiments using eight volunteers confined in a box for six hours.
The gases escaping from the box were gathered up and passed through a cylinder filled with building materials simulating more than two metres of rubble from a glass and reinforced concrete building.
A wide array of instruments measured what came through the materials.
The team found a number of molecules that were detectable, principally carbon dioxide and ammonia, along with acetone and isoprene.
The demonstration “signs of life detector” that the team used “worked beautifully”. Professor Thomas said.
“Our chemical sensors detected what we were looking for rapidly, within an hour of someone being ‘buried’ there.”
The team will carry out further tests using longer periods in the simulator. as the volunteers spend longer and longer time without food, a different array of “metabolite” chemicals should become apparent, as well as chemical components of urine that trapped victims would likely release.