Characterizing and Comparing Per- and Polyfluoroalkyl Substances in Commercially Available Biosolid and Organic Non-Biosolid-Based Products

Abstract

There is increasing concern over the presence of per-and polyfluoroalkyl substances (PFAS) in biosolids, while sales in commercially available biosolid-based products used as soil amendments are also increasing.Here, the occurrence of 17 perfluoroalkyl acids (PFAAs) present in 13 commercially available biosolid-based products, six organic composts (manure, mushroom, peat, and untreated wood), and one food and yard waste compost were studied. The PFAA concentration ranges observed are as follows: biosolidbased products (9.0−199 μg/kg) > food and yard waste (18.5 μg/kg) > other organic products (0.1−1.1 μg/kg). Analysis of 2014, 2016, and 2018 bags produced from one product line showed a temporal decrease in the total PFAAs (181, 101, and 74 μg/kg, respectively). The total oxidizable precursor (TOP) assay revealed the presence of PFAA precursors in the biosolid-based products at much higher levels, when the soluble carbon was removed by the ENVI-Carb clean-up prior to the TOP assay. Time-of-flight mass spectrometry confirmed the presence of three sulfonamides, two fluorotelomer sulfonates, and several polyfluoroalkyl phosphate diesters. Pore-water concentrations of water-saturated products were primarily of short-chain PFAAs and increased with increasing PFAA concentrations in the products. A strong positive log-linear correlation between organic carbon (OC)-normalized PFAA partition coefficients and the number of CF n units indicates that OC is a good predictor of PFAA release concentrations.

Sources, Fate, and Plant Uptake in Agricultural Systems of Per- and Polyfluoroalkyl Substances

“…All these biosolid and non-biosolid waste-derived composts contained PFOA and PFOS even though phase out was several years earlier than when these materials were produced. Several PFAS precursors were also detected with the most common being the 6:2 diPAP and 6:2 FTS [35,59]. Likewise, total PFAAs up to 80 ng/g dw were found in biowaste from biogas production [31].…”

“…PFAS are also present in non-biosolid urban waste-derived composts made from compostable paper products, food wastes, and tree and grass clippings. Total PFAAs in organic waste composts ranged from 31 to 75 ng/g for those containing food packaging with PFAS concentrations being lower in composts of only food and yard wastes (≤ 18.89 ng/g) [35,59]. All these biosolid and non-biosolid waste-derived composts contained PFOA and PFOS even though phase out was several years earlier than when these materials were produced.…”

“…Most commercially available waste-derived products sold in local or major store chains, which are typically purchased for use in urban and sub-urban gardens, golf courses, and public and homeowner lawns, have been found to contain PFAS. Kim Lazcano et al [59] found 9.0-181 ng/g of total PFAAs in commercially available municipal biosolid-based products. PFAS are also present in non-biosolid urban waste-derived composts made from compostable paper products, food wastes, and tree and grass clippings.…”

“…Likewise, total PFAAs up to 80 ng/g dw were found in biowaste from biogas production [31]. Overall shorter-chain PFAAs were higher in municipal solid waste-and biowastederived amendments compared to biosolid-based products [31,35,59]. Other waste-derived materials used as soil amendments that have not been studied for PFAS occurrence include paper mill wastes [65] which are expected to contain PFAS associated with PFAS-based paper coatings.…”

Regulating PFAS as a Chemical Class under the California Safer Consumer Products Program

“…PFAAs and some of their precursors are widespread in the environment, including in air (Kim and Kannan 2007;Muir et al 2019;Wang et al 2019), dust (Haug et al 2011;Eriksson and Kärrman 2015;Yao et al 2018;Shin et al 2020), wastewater treatment plant effluent (Hamid and Li 2016;Wang et al 2016;Houtz et al 2016;H Chen et al 2017), biosolids (Letcher et al 2020;Kim Lazcano et al 2020), soil (Rankin et al 2016;Dalahmeh et al 2018;Muir et al 2019;Washington et al 2019), snow (Kim and Kannan 2007;Kirchgeorg et al 2016), inland and ocean waters (Prevedouros et al 2006;Zhao et al 2012;Wang et al 2016;Muir et al 2019), drinking water (Gellrich et al 2013;Wang et al 2016;Boone et al 2019), and human foods (Pérez et al 2014;Gebbink et al 2015;Domingo and Nadal 2017;Christensen et al 2017;EFSA CONTAM Panel et al 2018). As a result, human (Cariou et al 2015;Calafat et al 2007;Chang et al 2014;Fraser et al 2013;Kang et al 2016;Monroy et al 2008;OECD 2013;Olsen et al 2007b;Tao et al 2008a…”