Researchers at the Hebrew University of Jerusalem say they may have found a way to remotely detect unexploded landmines by using a combination of lasers and molecularly engineered bacteria that glow in proximity to the explosives.
Buried landmines, which injure or kill 15,000-20,000 people each year, emit tiny quantities of explosive vapors which accumulate in the soil above them. This observation prompted the Hebrew University researchers, led by Prof. Shimshon Belkin of the Alexander Silberman Institute of Life Sciences, to use bacteria that emit a fluorescent signal when they come into contact with these vapors to detect the mines.
They enclosed the bacteria in small polymeric beads, which were then scattered across the surface of a test field in which real antipersonnel landmines were buried. Using a laser-based scanning system, the test field was remotely scanned and the researchers were able to determine the location of the buried explosives.
About half a million people around the world suffer from mine-inflicted injuries and more than 100 million such devices are still buried in over 70 countries. The major technical challenge in clearing minefields is detecting the mines. The technologies used today are not much different from those used in World War II, requiring detection teams who risk life and limb by physically entering the minefields.
Accidents involving landmines occur in Israel once every few years and landmines laid in the 1950s and 1960s contaminate the Arava Valley, areas along the Jordan Valley and the Golan Heights, which Israel captured from Syria during the 1967 Six Day War. The landmines have largely been demarcated by a network of fences and warning signs.
The Hebrew U researchers said that the signals from the bacteria can be recorded and quantified from remote locations, making their test field, they believe, the first time landmines have been detected remotely.
“Our field data show that engineered biosensors may be useful in a landmine detection system,” said Belkin in a statement.
But to make this possible, more work needs to be done, he said, including enhancing the sensitivity and the stability of the bacteria, improving scanning speeds to cover large areas, and making the scanning apparatus more compact so that it can be used aboard a light unmanned aircraft or drone, he said.
The researchers presented their new system in the Nature Biotechnology journal.