PFAS impact on soil microbial diversity and community

Abstract

Per- and polyfluoroalkyl substances (PFAS) are persistent environmental pollutants that pose risks to soil health and microbial ecosystems due to their chemical stability and resistance to degradation. These “forever chemicals,” are widespread in the environment, yet their impact on soil microbiomes remains poorly understood. We investigated how PFAS contamination impacts microbial diversity, community composition, and taxonomic structure in both field and controlled laboratory settings. Soil samples from PFAS-contaminated (Sites A and B) and uncontaminated (Site C) locations were analyzed alongside laboratory microcosms, exposing microbial communities to varying PFAS concentrations (high, low, none) under short-term (7-day) and long-term (4-month) incubation. We hypothesized that increasing PFAS concentrations would reduce microbial diversity and selectively enrich PFAS-tolerant organisms. Alpha diversity revealed contrasting patterns: PFAS-contaminated soils exhibited significantly higher richness and evenness, while PFAS treatments in the microcosms initially reduced microbial diversity. Over time, diversity partially recovered, reflecting on potential microbial adaptation. Beta diversity analyses revealed significant shifts in community composition across both field and enrichment settings, shaped by PFAS concentration and exposure duration. We identified consistent enrichment of stress-tolerant or potentially PFAS-degrading taxa (e.g., Pseudomonas, Cupriavidus, Paracoccus), alongside depletion of functional groups involved in soil processes (e.g., Geothrix, Thermoleophilia, Acidobacteriota). These shifts indicate PFAS act both as a selective pressure and a disruptor of key ecological functions such as nutrient cycling and redox buffering. This study provides better understanding of PFAS–microbiome interactions and highlights the potential of native microbial taxa in monitoring and mitigating PFAS contamination through bioremediation.