Blow flies can finally serve a useful purpose – as chemical warfare investigators!

INDIANAPOLIS, Indiana— Pesky flies may have finally found a reason for you not to swat them: they can detect the use of chemical weapons! Blowflies are able to scour through a battlefield, searching for traces of chemical warfare agents and other toxins, a new study reveals.

Researchers from the Indiana University School of Science at Purdue University Indianapolis (IUPUI) have found that insects act as chemical sensors, literally tasting the environments they pass through and then storing these chemical samples in their gut for up to two weeks.

Flies could find evidence of war crimes

Although international laws prohibit the use of chemical weapons, the study’s authors say there is evidence proving their use during the recent Syrian civil war and many people fear the same could happen in Ukraine. at one point. The team adds that blowflies offer a safer alternative to sending people into dangerous areas as investigators search for these illegal weapons.

“Blowflies are ubiquitous and they are very adept at sampling the environment around us,” says Christine Picard, associate professor of biology and director of the forensic and investigative science program at IUPUI, in a university outing. “They will fly through the environment, taste it, and this information will be stored in their guts. Through a series of experiments, we were able to examine the impact of different environmental factors on their detection of chemical weapons simulants.

Flies can store toxins before they are gone

The researchers conducted their experiments using chemical weapons simulants. Although they share similar characteristics with chemical weapons and pesticides, they are not toxic to humans. The team notes that pesticides are also similar to chemical warfare agents in terms of molecular behavior.

“We used a mass spectrometer to determine what chemicals were in the guts of blowflies,” says Nick Manicke, associate professor of chemistry and chemical biology and forensic and investigative sciences. “We were able to detect chemical warfare agent simulants, as well as some of the things chemical agents break down into once they are in the environment. If a fly were to land on a water source, with a hydrolyzed chemical agent in the water, we would find that in the fly.

One of the problems with proving the use of chemical weapons is that they don’t last long in the environment. However, the study authors found that a fly’s gut could retain these traces for up to 14 days after the insect’s initial exposure.

“If an area is too dangerous, too remote or in a restricted area – or if one just wanted to take samples in secret – then just put some bait in and the flies will come to the bait,” says Manicke. . “We can sweep large areas by luring flies into a trap and analyzing what they have in their guts.”

Clean the environment, too?

The researchers say that blowflies could also help environmental scientists understand the impact of pollutants such as pesticides on the planet.

“Thanks to the collaboration between Dr. Manicke and Dr. Picard, we were able to work on a project that could have a direct impact,” says the co-author and Ph.D. Sarah Dowling, student. “It is gratifying to know that the work we have done throughout this project could improve the safety of combatants and others who handle chemicals in the environment.”

The team will now apply their findings to a two-year study focused on detecting molecules from “insensitive munitions”. This is a new type of explosive that is less likely to detonate by accident. However, this means that they also deposit more chemical residues in the environment.

Blowflies will head to remote and dangerous areas, looking for traces of these munitions compounds, while scientists examine their impact on the local environment.

The study is published in the journal Environmental science and technology. The US Defense Advanced Research Projects Agency funded the study.