Development and validation of a novel HPLC-MS/MS method for the quantitative determination of PFASs in non-hazardous solid waste samples

Perfluoroalkyl substances (PFASs) are a heterogeneous group of fluorinated synthetic compounds characterised by the presence of a hydrophobic carbonyl chain at different fluorination rates and by a terminal hydrophilic group. Because of their persistence and mobility, PFASs have been widely detected in ecosystems and living organisms, leading to their classification as persistent organic pollutants (POPs). Hence, monitoring the PFASs content in solid waste meant for disposal in non-hazardous landfills can be crucial, since leachate can pose a significant pollution threat to farmlands and aquifers. Therefore, a QuEChERS and SPE pretreatment with HPLC-MS/MS detection method for 10 different PFASs in solid waste samples was developed in this study. Different sample preparation approaches have been evaluated, taking into account the lack in the literature of this complex matrix. An innovative application using the Captiva EMR cartridge for the clean up (designed to be applied to lipidic matrix) was proposed and a multiresidual HPLC-MS/MS method for the analysis of PFASs in internal waters was extended to the investigation of non-lipidic samples as solid wastes. The method was then validated through 6 blanks and 6 spiked samples, according to the UNI EN ISO/IEC 17025. The optimized method showed satisfactory performance with recoveries ranging from 89.8 % to 106.5 % and with LOD and LOQ ranging between 0.0023 – 0.09 µg/L and 0.006 – 0.13 µg/L, respectively, for each of the PFASs under consideration. In addition, this approach demonstrated to be reliable and time consuming due to its capability for determining PFASs in waters and in solid wastes simultaneously in a single chromatographic run.