Researchers at Michigan State University are exploring an unexpected new tool that could reshape how scientists detect so-called forever chemicals in lakes, rivers and wetlands across the Great Lakes.
Scientists have discovered that locusts can sniff out PFAS contaminants down to parts per trillion, a level of detection far beyond most conventional sensors.
The new tool: insects.
“This tells us insects can detect PFAS at very, very low concentrations,” said Dr. Debajit Saha, an associate professor of biomedical engineering at MSU, who has spent years studying how insects process smells. “It opens the door to developing a real‑time scanning device that could be deployed in the Great Lakes region.”
PFAS are a class of chemicals used for decades in firefighting foam, non‑stick cookware, water‑resistant clothing and countless consumer products. The chemicals earned the nickname “forever chemicals” because they do not break down easily and accumulate in the environment, wildlife and even human bodies. Studies have linked PFAS exposure to various diseases, and contamination has intensified over the last decade.
Current PFAS detection relies on liquid chromatography–mass spectrometry (LC‑MS), a powerful but slow laboratory method. It can identify PFAS, but not instantly, and not in the field. No existing device can rapidly detect multiple PFAS types or mixtures in real time.
To address this gap, Saha’s team turned to locusts. By recording neural activity from the insect’s antennal lobe, the part of the brain that processes smells, researchers discovered that locust neurons respond to PFAS compounds, including PFOA, one of the most common contaminants found in Michigan waters.
Summer McLane-Svoboda, a doctoral candidate and graduate research assistant in Saha’s lab and lead author of the study, has already shown that insect brains can reliably detect PFAS across a range of concentrations. The team is now collaborating with the MSU PFAS Center to test environmental samples from known contaminated sites.
“Our current next steps that we’re working on is collecting environmental samples from known contaminated sites here in Michigan through the PFAS Center and then testing those samples to see if we can distinguish between a polluted sample versus a healthy or a natural environmental sample,” McLane-Svoboda said.
One of those sites is Clark’s Marsh in Michigan’s northern Lower Peninsula, a location long identified as PFAS‑contaminated. The researchers also use samples from nearby Tuttle Marsh, which is not contaminated, to calibrate their sensor.
“One of the first things that can help is just determining if a site is polluted with PFAS or not,” McLane-Svoboda said. “That way, we can then zone it off as a contaminated site, which impacts different consumption policies or fishing policies within that area as well.”
Saha hopes that one day, people across Michigan could send water samples to a centralized lab equipped with insect‑based sensors. Researchers could then map PFAS contamination statewide, identifying hotspots and tracking changes over time.
“We’re not there yet,” Saha said. “But in the future, we’d like to test samples from different areas and map out how the Michigan environment looks in terms of PFAS contamination.”
Such a system would require coordination with government agencies and environmental groups, but the researchers believe it’s achievable.
When asked how the public can help, both Saha and McLane-Svoboda emphasized awareness. PFAS are present in many household products, and labeling has improved in recent years. Consumers can reduce exposure by reading packaging and avoiding products that contain PFAS.
“Spreading awareness through articles and news outlets helps a lot,” McLane-Svoboda said. “Knowing what’s in your consumer products can help prevent further exposure.”
The research is funded by the National Science Foundation, making public engagement even more important. The team sees it as part of their responsibility to share knowledge through publications, interviews and conferences.
Saha acknowledges that their work is still in its early stages, but they believe it has the potential to transform how PFAS pollution is monitored and managed.
“It’s a small idea we’re trying to grow,” Saha said. “But if we can make this work, it could be a game changer.”