PFAS in commercially available organic amendments and food-contact paper products

Composting solid waste materials creates a nutrient-rich soil amendment and reduces the burden on landfills and incineration facilities. However, the presence of per- and poly-fluoroalkyl substances (PFAS) in various waste-derived products used as soil amendments poses potentially significant risks to human health and the environment. This study aimed to establish baseline knowledge on the presence and level of 13 PFAS compounds across five commercial composts, three soil amendments, two biosolid-derived fertilizers, and five common food-contact paper products (K-O). The total concentration of 13 PFAS compounds (Ʃ13 PFAS) among the products was as follows: biosolid-based fertilizers (25.41 ± 12.98 μg/dry kg, n = 2) > compost (9.07 ± 12.22 μg/dry kg, n = 5) > soil amendments (1.99 ± 0.23 μg/dry kg, n = 3). The total concentration of perfluorinated carboxylic acids (ΣPFCAs) was higher than that of perfluoroalkyl sulfonic acids (ΣPFSAs) and perfluorooctane sulfonamide (FOSA) across all product categories. Short-chain PFCAs, such as perfluorohexanoic acid (PFHxA), and long-chain PFCAs, such as perfluorooctanoic acid (PFOA), were prevalent in yard waste composts, while the long-chain PFSA, perfluorooctane sulfonate (PFOS), was most prevalent in biosolid-based fertilizers. In food service paper products, the highest concentrations were observed for PFHxA, perfluorobutanoic acid (PFBA) and perfluorohexane sulfonate (PFHxS). This study emphasizes that besides waste products, conventional coating materials, such as food-contact paper products, which are frequently accepted without testing, represent a significant source of PFAS. These findings contribute to identifying potential contamination sources and informing science-based regulations aimed at improving compost quality and ensuring public safety. The insights provided here are expected to support environmental monitoring and policymaking efforts. Further large-scale surveys across diverse geographical areas should validate our findings. This work underscores an urgent need for stricter regulations and innovative solutions to mitigate PFAS contamination while advancing sustainable agriculture and circular waste management practices.