BioExplorers: Mice Bomb Sniffing Technology

Mice used as a bomb detector – Bioexplorers
Israeli start-up named BioExplorers developed a technology which uses mice to detect explosives which could be used for homeland security improving safety in airports and border crossings. The new system should go on its first pilot program in the next few months.
Dogs have been used to detect explosives and narcotics for a long time. Interestingly there seem to be a more powerful nose in the animal kingdom which can be used as a super biosensor. The Israeli company BioExplorersharnessed the olfactory skills of mice, which is the main sense they used to look for food, mating and avoiding predators and turned it into a super sensitive bomb detection biosensor. Mice are actually so sensitive at detecting smells that they can actually discover even the smallest trace of vapor on the order of parts per trillion.
Unlike dogs which needs long training and require regular motivation to help build and maintain their olfactory capabilities, mice use the same capabilities all the time to survive and so require very little training and motivation to act.
BioExplorers is comprised of a team of experts in animal behavior who created an innovative computerized method for training the rodents to detect copious target substances including different types of explosive materials, variety of narcotics, agricultural products, spoiled food, disease markers and more.
The detector which is based on the rodent detection technology resembles a full-body scanner which you can find in many airports these days. The detection unit includes 3 hidden cartridges with 8 mice in each of them (typically only females to prevent distractions). Each "shift" of mice work for about 4 hours inside the detector as air is passed over people and sucked into the cartridges. If the mice sniff any of several target scents (emitted by explosives) they are conditioned to avoid the scent and run to a side chamber which will immediately be detected by the computerized tracking system. However to avoid false positives the system requires that more than one rodent will recognize a suspected material at the same time.
The system has already undergone real world testing. The "mice detector" was placed in a busy shopping mall in Tel Aviv and more than 1000 people had passed through it with 22 of them wearing concealed packages with dummy explosives. All 22 people were recognized by the system and more importantly, the false alarm rate was around 0.1%.
There are downsides to the mice technology – unlike non biological detectors they need to rest (and they actually get very well treated when not inside the detector with plenty of food, water and exercise), the rodents also can’t detect sharp objects such as knives so some sort of metal detector is also required.  
More information on the mice detector technology can be found on the bioexplorers website.

A video showing a test of the system which took place last year