Targeted and non-targeted per- and polyfluoroalkyl substances (PFAS) characterization in irrigation waters across
Magdalena Cara1, Dhimiter Bello2, Kushal Biswas2
1Department of Plant Protection, Faculty of Agriculture and Environment, Agricultural University of Tirana, Paisi Vodica 1025, Tirana, Albania; Regional Center of Nanotechnology, NanoBalkan, Academy of Sciences of Albania, Murat Toptani Avenue, Tirana, 1000, Albania.
Abstract:
Per- and polyfluoroalkyl substances (PFAS) are an emerging environmental concern in agriculture due to their persistence, mobility, and potential to enter the food chain through irrigation. This study presents the first nationwide assessment of PFAS occurrence in surface and groundwater used for irrigation across Albania. Seventy-seven water samples were collected from (i) surface water irrigation sites (rivers, streams, and reservoirs), (ii) groundwater systems (wells), and (iii) water bodies located near industrial sites with potential PFAS discharges. Samples were analyzed using complementary targeted and non-targeted mass spectrometry approaches: 1) targeted quantification of 46 PFAS by LC-ESI-MS/MS and 2) high-resolution non-targeted screening against a PFAS database of ∼7000 structures using LC-HR-QTOF-MS/MS. Targeted analysis detected 22 PFAS, dominated by ultra and short-chain compounds (C2-C6). Perfluoropropionic acid (PFPrA, C3) was present in 100% of samples, whereas long-chain legacy PFAS (C7-C12), including perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA), were detected less frequently (3-23%). The sum of detectable PFAS (ΣPFAS) concentrations ranged from 4.7 to 2.2 × 106 ng/L, with the highest levels detected in waters influenced by hospital and oil-processing effluents. Non-targeted screening of seven representative samples resulted in the annotation of 33 PFAS compounds, including 13 additional PFAS not included in the targeted analyte list. Among these were perfluoroalkane sulfonamido amines (PFSAAm) and fluorotelomer sulfonates (FTS) indicating that targeted analysis may underestimate the diversity of PFAS present in water samples. Elevated concentrations near industrial and hospital discharges underscore the need for regulatory monitoring and improved effluent treatment. By integrating targeted and non-targeted analytical approaches, this study provides a more comprehensive characterization of PFAS diversity in irrigation waters and establishes a baseline for future national monitoring and agricultural risk assessment in Albania.
