Locating land mines with 'artificial nose.' (Tufts Univ is developing artificial nose that uses sensing chemistries to detect TNT in land mines) (Brief Article)

Roughly 120,000,000 land mines are scattered throughout the world and are responsible for maiming or killing 24,000 people each year. Many of those injured are civilians in Third World countries, where farms and fields were transformed into battlegrounds. Vietnam has 3,500,000 mines; Cambodia, 10,000,000; and Bosnia and Croatia, 12,000,000.

Getting rid of land mines is expensive and risky. According to the international Red Cross, one demolition specialist is killed and two injured for every 500 mines that are removed. Researchers at Tufts University, Medford, Mass., are hoping that the artificial "nose" they developed can be used to sniff out land mines, reducing the toll the weapons have on human lives. The trick is to refine the device so it can detect the low concentration of TNT often left on the surface of a land mine. Because TNT is sticky, it frequently contaminates the outside of mines.

"A major part of our work will be studying the biological olfactory system and how it deals with low concentration signals," explains John S. Kauer, professor of neuroscience. "The odors of land mines are low concentration, so one has to have an extremely sensitive device. We know dogs can do this; we are trying to learn from the biology to extend the sensitivity of the artificial system."

The artificial nose is based on technology in which sensing chemistries are deposited on the ends of optical fibers. "The sensing device -- the part out there in the field sniffing -- can be moved by an autonomous vehicle or...