There have been some studies suggesting biological defluorination of certain PFAS could occur, but additional research is needed to fully understand the potential for biodegradation to reduce the risks posed by PFAS present in AFFF formulations. SERDP has funded prior work demonstrating that perfluoroalkyl acid (PFAA) precursors were transformed to PFAAs, also confirming that PFAAs are recalcitrant under typical environmental conditions. Additional efforts are being conducted to further explore biodegradation potential of PFAS in the field.