About Canine Detection
Using dogs for a variety of detection tasks began more than five decades ago. Today, dogs are widely used by local, state, and federal law enforcement, the military, private and security companies. This growth and widespread acceptance is explained by one key factor - dogs can be extremely effective.
It has been estimated that a dog's olfactory system is 10 thousand to 10 million times greater than that of a human. A dog has 220 million scent cells as compared to about 5 million for a human. Dog scent cells line the canine mucosa, a membrane at the rear of the snout, which is folded so many times that, if smoothed out, it would be larger than the dog's body.
Based on laboratory testing at Auburn University's Canine Performance Sciences, dogs can detect certain scents in a concentration at least as low as 500 parts per trillion. To put that into perspective, that's like buying one lottery ticket out of two billion (a third of world's population) and winning every time.