Fruit Flies Could Sniff Out Bombs, Drugs

A fruit fly's sense of smell could potentially be used to sniff out bombs and drugs, according to a new study.

Fruit flies (Drosophila melanogaster) can detect smells such as those from wine, which the insects are naturally attracted to because it smells like their favorite food, fermenting fruit. Now, new research shows that their keen "noses" could with just as much accuracy identify odors from illicit drugs and explosive substances as well.

Published in the journal Bioinspiration and Biomimetics, the study brings scientists closer to developing electronic noses, or e-noses, that closely replicate the strong sense of smell of animals like the fruit fly.

"Dogs can smell drugs and people have trained bees to detect explosives. Here we are looking more for what it is in the nose - which receptors - that allows animals to do this," Professor Thomas Nowotny, a brain scientist at the University of Sussex, said in a statement.

"In looking at fruit flies, we have found that, contrary to our expectation, unfamiliar odors, such as from explosives, were not only recognized but broadly recognized with the same accuracy as odors more relevant to a fly's behavior," he added.

Nowotny, who led the study alongside researchers from Monash University and CSIRO in Australia, recorded how 20 different receptor neurons in fruit flies responded to various chemicals. A group of 36 chemicals were related to wine and a separate 35 were related to hazardous materials, such as those found in drugs, combustion products and the headspace of explosives. By monitoring the "firing rate" of each neuron, the researchers could tell which chemicals caused the strongest reactions in the flies.

Of the wine set, 29 out of the 36 compounds elicited clear excitatory responses in at least one receptor neuron. They were surprised to find, however, that the flies also responded to 21 out of the 35 substances related to drugs and explosives.

"The long-term goal of this research direction is to 'recreate' animals' noses for technical applications," Nowotny said.

"And, of course, the fly's success in identifying the 'wine set' might prove useful for those in the winemaking industry," he quipped.