A recent study published in the journal Environmental Science & Technology highlights a promising approach to mitigating the environmental impact of per- and polyfluoroalkyl substances (PFAS), commonly known as “forever chemicals.” Researchers Bo Hu, Feng Zhao and colleagues showed the superhuman power of a fungus called Rhizophagus irregularis. When this fungus is paired with the invasive yellow flag iris plant (Iris pseudacorus L.), it significantly increases wetlands’ ability to absorb and filter out PFAS from contaminated water sources.
Wetlands provide an important ecological role, sometimes described as nature’s kidneys. They trap sediments, absorb excess nutrients, and transform pollutants into less harmful substances. The study was primarily interested in finding the best wetland plants for filtering PFAS. It looked at these capabilities both in the presence and absence of R. irregularis, providing important information for future remediation efforts in polluted waterways.
Experimental Setup and Findings
In this research, scaled-down wetland treatment systems were used to replicate natural conditions. To test these systems, researchers subjected them to solutions that simulated wastewater with high concentrations of PFAS. Some of these wetlands even received one of four separate PFAS at environmentally relevant concentrations. At the same time, other wetlands acted as control sites and were not inoculated with the fungus.
Results AMF yellow flag iris plants grew larger than non-AMF-treated plants in all measured performance metrics. They were able to remove up to 10% – 13% more individual PFAS compounds compared to treatment without the fungus. Furthermore, the AMF-treated plants obviously preferred long-chain PFAS. In fact, they utilized more of these compounds than the short-chain variants in their shoots and roots.
“Our study shows that a type of fungus (Rhizophagus irregularis) boosts wetlands’ ability to remove PFAS and greatly reduces the environmental risks from ‘forever chemicals’ left in the outflowing water,” – Bo Hu
From the experiment, we found that all outflow samples contained detectable levels of PFAS – a crucial reminder about the persistent nature of PFAS contaminants. The total PFAS reduction was substantial — 17% to 28% — with many of the outflow samples from the fungal tubes showing complete PFAS degradation. This is a clear indication of how powerful arbuscular mycorrhizal fungi (AMF) can be at increasing the plants’ filtering powers.
Implications for Future Wetland Restoration
The findings from this study suggest that incorporating arbuscular mycorrhizal fungi into wetland restoration efforts could play a significant role in enhancing pollutant removal. By improving the resilience of wetland plants under PFAS stress, these symbiotic relationships may facilitate better translocation and transformation of harmful chemicals.
The studies suggest moving in the direction of building more robust wetland-based cleanup techniques, which could lay the groundwork for innovative technologies capable of removing PFAS. Yet, this research has far-ranging potential applications that extend well beyond the historical boundaries of wetlands. It raises larger questions for these engineered solutions designed to remediate ecological contamination in all ecosystems.
“These results are key for developing stronger wetland-based cleanup methods and could inspire new technologies for removing PFAS.” – Bo Hu
The study’s implications are being felt far and wide across the scientific community and environmental management field. With increasing regulatory pressures on PFAS, identifying removal techniques is of the utmost importance.