PFAS in biosolids: A review of international regulations
Per- and polyfluoroalkyl substances (PFAS) are incredibly useful additives, often providing excellent surface tension-lowering properties to a material. Due to the extensive use of PFAS in daily life in developed countries, PFAS invariably collects in municipal wastewater. Without targeted removal of PFAS at wastewater treatment plants, PFAS can move through the treatment process into both the recycled water and biosolids. The presence of PFAS in biosolids poses a potential challenging problem to society for many reasons. A small number of countries have cautiously started, or have at least considered, limiting the concentration of PFAS permitted in biosolids that are to be used for land application. Our review covers the current limits on PFAS concentrations in Australian biosolids, along with the latest developments in international regulations. We found that only Maine, USA, has set upper limits of PFAS for “beneficial use of solid wastes”. Denmark, Germany, The Netherlands, Sweden and Australia have set PFAS limits in soils. No other countries were found to have PFAS limits relating to biosolids or their use; however, this also reflects the lack of industrialisation and centralised wastewater management in many parts of the world.