After familiarisation, they can also detect allergens (such as peanuts in food) and alert people for whom such things are dangerous. By the process known as biodetection, dogs can be trained to recognise the very slight odour caused by chemical matter in the early stages of various cancers: breast, bowel, uterine, bladder, prostate, lung and melanoma.
With their fine scent-analysis powers, they can detect when a diabetes-prone person’s blood sugar level is becoming dangerously low. They can even sense when a seizure of some sort (such as epilepsy), is about to happen – and can bark for help and paw the person towards a safer place.
They can be trained to find truffles, locate termites in buildings and recognise the presence of alien bugs before they become established beyond control (for example, in vineyards). Their impressive ability to seek and identify scents plays an important role in the law-and-order battle against illegal drugs. Sniffer dogs on searching missions or at airports, can identify seeds, vegetations and forbidden fruits with ease and can detect drugs even when packed tightly amid mothballs. According to an official, a dog can ‘screen people faster than an X-ray machine’.