The SURFAS project conducts the first nationwide survey of background concentrations of per- and polyfluoroalkyl substances (PFAS) in animal feed from agricultural areas in Switzerland presumed to be uncontaminated. The study focuses mainly on herbages, complemented by maize and concentrate feed. A coordinated sampling campaign across several cantons collects forage and soil samples simultaneously to:

1. determine PFAS background levels in key feedstuffs,
2. assess soil-to-plant transfer factors,
3. identify influencing factors such as soil properties, botanical composition, climate and management, and
4. model transfer to milk, meat and offal using a toxicokinetic (PBTK) approach to evaluate food safety risks.

The project includes four work packages: grassland, maize and concentrates, soils and transfer, and risk assessment. In total, 130 samples will be analysed for around 30 PFAS. Results will support authorities and the agricultural sector in establishing national reference values and potential regulatory measures.