Scientists working in the labs of Rajib Saha and Nirupam Aich have found that a widespread photosynthetic bacterium, Rhodopseudomonas palustris, can interact with perfluorooctanoic acid, a highly resistant member of the PFAS family. Their study, published in Environmental Science: Advances, reports that the bacterium draws PFOA into its cell membrane -- a behavior that changes over time.
This discovery offers an early look at how natural microbes might eventually be guided or engineered to help reduce PFAS pollution, potentially supporting efforts to protect water quality and public health.
Early Experiments Reveal Promise and Limitations
During controlled lab tests, the researchers noted that R. palustris removed about 44% of PFOA from its surroundings within 20 days. Much of that absorbed chemical later returned to the environment, most likely because the cells broke apart -- a result that underscores both the usefulness and the challenges of relying on living microorganisms to capture or alter PFAS.
"While R. palustris didn't completely degrade the chemical, our findings suggest a stepwise mechanism where the bacterium may initially trap PFOA in its membranes," said Saha, Richard L. and Carol S. McNeel Associate Professor. "This gives us a foundation to explore future genetic or systems biology interventions that could improve retention or even enable biotransformation."
Collaborative Expertise Strengthens the Research
The Aich Lab provided specialized PFAS detection capabilities, allowing the team to track changes in PFOA levels with high accuracy. At the same time, Saha's group carried out the biological experiments and examined how the bacterium responded to different PFAS concentrations.
"This kind of collaboration is exactly what's needed to address complex environmental challenges," said Aich, Richard L. McNeel Associate Professor. "By bringing together microbiology, chemical engineering, and environmental analytical science, we're gaining a more complete picture of how to tackle PFAS pollution with biological tools."
Toward Scalable Microbial Approaches for PFAS Cleanup
PFAS compounds remain a worldwide issue because they persist in soil and water for long periods. Existing treatments can be expensive and require significant energy. Microbial strategies may offer a more adaptable and less resource-intensive path forward -- although substantial scientific development is still necessary.
The findings from this project point toward that direction, and the research teams are already planning additional studies focused on microbial engineering and synthetic biology to improve future degradation capabilities.
Funding and Access to Findings
This collaborative effort was supported by Layman Award and Nebraska Collaboration Initiative Grant Awarded to Aich and Saha. Two doctoral candidates -- Mark Kathol from Saha Lab and Anika Azme from Aich Lab -- are the two co-first authors of this study.
The full study is available open-access via the Royal Society of Chemistry.
