PFAS in agroecosystems: Sources, impacts, and opportunities for mitigating risks to human and ecosystem health.

Concerns regarding per- and polyfluoroalkyl substances (PFAS) and their precursors have driven increased research into their sources, impacts, and mitigation strategies, aiming to reduce their prevalence in the environment. While much of this research has centered on known large sources of PFAS (e.g., military bases, airports, fire training sites, and some manufacturing facilities), there has been increased interest in evaluating the inadvertent introduction of PFAS into agroecosystems from beneficial reuse of treated domestic wastewater for irrigation and land application of biosolids and composts derived from food waste. Additional sources to agricultural fields include the use of PFAS-containing pesticides. These activities raise questions regarding the potential impacts of PFAS introduced to agricultural systems on rural water supplies, soil health, and food safety. This special section contains papers that fall into three categories: (i) source assessment of PFAS in water and wastewater residuals destined for beneficial reuse in agroecosystems, (ii) improved understanding of PFAS fate and transport in agroecosystems following land application of PFAS-containing materials, and (iii) small-scale assessment of techniques that demonstrate promise for mitigating PFAS mobilization in agroecosystems. The work contained in this special section can be used to help guide future decisions related to PFAS guidelines, policies, and regulations in agroecosystems intended to protect human and ecological health.