[Assessment on data processing methods for nontarget identification of per- and polyfluoroalkyl substances using liquid chromatography-high-resolution mass spectrometry].

The widespread use， persistence， bioaccumulation， and toxicity of per- and polyfluoroalkyl substances （PFAS） have raised global concern. The number of PFAS types continues to grow， driven by changing industrial demands and regulatory environments. Non-target analysis using high-resolution mass spectrometry （HRMS） is an effective methodology for identifying novel and unknown PFAS in environmental matrices. The efficacy of non-target analysis is critically influenced by the data acquisition mode， peak picking algorithm， and deconvolution strategy. Using ultra-high performance liquid chromatography coupled with an Orbitrap mass spectrometer （UHPLC-Orbitrap MS）， this study aims to systematically evaluate data processing methods for non-targeted PFAS identification under data-dependent acquisition （DDA） and data-independent acquisition （DIA） modes. A clean sludge sample was spiked with 34 PFAS standards at three levels to assess method performance， alongside the analysis of three electroplating sludge samples. To compare the identification performance between DDA and DIA modes， a multi-step evaluation process was employed. Firstly， we assessed the peak picking capabilities of two widely used data processing software packages， MS-DIAL and MZmine. The key parameters for peak picking process are MS