Bio-sensing for Drug Detection
We don’t usually think of it this way, but when a police officer pulls someone over and uses “a smell of alcohol” to justify further investigation, they are using a bio-sensor – their own nose. The police also rely on dogs as sensors for everything from bomb to drug detection. The is to repurpose an existing biological system to find what your own senses cannot detect.
Following this idea, scientists look for other animals who can detect the very small amounts of scent that give away the presence of illegal substances. One of the strangest versions of this is available in the UK – it uses bees.
Insentinel Ltd makes a handheld scanner type device that holds live bees. The air going to the bees passes through a filter until the operator pushes a button, allowing sample air inflow. The bees, who have been trained on any of a number of substances, react by sticking out their tongues. A cartridge containing 36 bees then registers a positive if enough of the bees react.
While the idea of using insects to detect drugs or explosives seems farfetched, the technology may find use as a cheaper alternative to drug or bomb dogs. No training is needed (as with a dog handler) and the bees come in an almost unlimited supply. Each group of bees is good for a day or two and they are trained in a few minutes by exposing them to the sought after scent.
Even DARPA (the U.S. defense agency) is investigating the use of insects to detect roadside bombs in Iraq and Afghanistan.
Legal issues remain to be decided. For instance, while a sniffer dog is deemed good probable cause for a search, bees haven’t been tested in court yet. However, traffic police could use a bee unit and then, if they get a hit for drugs, call for a drug dog to verify. This is important because without a driver’s permission or probable cause, police cannot simply search a vehicle or its contents. Drugs transported in the trunk will escape detection without something like bio-sensing to sound an alarm.