PFAS concentrations range from 20 to 20,000 ng/L in groundwater, 11-23 ng/L in well water, 71 0.4-40 ng/L in drinking water, 5.1 to 298,559 ng/L in landfill leachate, 3-430 ng/L in wastewater influent, and 6-500 ng/L in wastewater effluent systems across USA, China, Europe, and Australia; PFAS composition was primarily represented by PFOA, PFOS and perfluorohexane sulfonic acid (PFHxS). Groundwater has been predominantly researched for PFAS treatment, driven by its prevalence, regulatory importance, ease of study, persistence, and ecological impact (Figure ). Fire extinguishing water, particularly from military and industrial sites using aqueous film-forming foam (AFFF), poses significant challenges for PFAS treatment due to high PFAS concentrations. Fluorine-free alternatives have shown improved biodegradability and reduced environmental persistence compared to AFFF. Nonetheless, some alternatives may still present similar or higher environmental impacts. Additional research is required to fully understand the sustainability of these alternative firefighting foams.