BEES SWEET ON TNT
Bomb-sniffing apiary team
Biologists in France and Croatia have successfully reared sniffer bees that they claim could find explosives hidden underground in the Balkans.
The insects are said to have an olfactory sense as strong as sniffer dogs. The researchers hope they will speed up the urgent task of clearing thousands of landmines disturbed in the worst flooding on record.
About one million mines, most containing TNT, were planted during the war in Bosnia in 1992-95. Nearly 120,000 of the unexploded devices remain in more than 9,400 minefields. The bad weather has destroyed warning signs and dis- lodged many of the mines.
“We knew that bees were sensitive to certain smells, like geraniums or nerol (a rose scent). The challenge was to get them to learn to spot TNT,” said Yves Le Conte, director of the bee and environment unit at INRA, in Avignon, southern France.
Dijana Plestina, head of the Croatian government’s de-mining bureau, said landmines represent a large obstacle for the country’s population and industry, including agriculture and tourism. In the nearly two decades since the end of the war, they have taken the lives of 316 people, including 66 deminers, she said.
“While this exists, we are living in a kind of terror, at least for the people who are living in areas suspected to have mines,” she said. “And of course, that is unacceptable. We will not be a country in peace until this problem is solved.”
In experiments, Le Conte hid TNT under sand covered with sugar syrup to attract the bees. This encouraged the insects to prefer pots with TNT in them.
The bees soon lose interest when they realize there is no sugar to be found, so have to be “re-educated” with sugar-coated TNT roughly every 30 minutes, Le Conte said.
This isn’t the first time scientists have tried to train bees to sniff out explosives.
In 2006, the Los Alamos National Laboratory in New Mexico released a study that suggested bees
We knew that bees were sensitive to certain smells ... The challenge was to get them to learn to spot TNT.
were better bomb detectors than man-made devices.
Nikola Kezic, an expert on the behaviour of honeybees and a member of the latest project, said the U.S. research differed in one key area: TNT wasn’t part of the experiment because its smell evaporates quickly, and only small traces remain after time.
Rats and dogs are also used to detect explosives worldwide, but unlike bees, they could set off blasts in the minefields because of their weight.
It may be a while before the honeybees hit real minefields, Kezic said. First, they will conduct controlled tests, with real mines that are marked.