Optimization and Validation of the SBSE–HPLC–FLD Method for the Determination of Priority Pollutants PAHs in Several Water Matrices

Polycyclic aromatic hydrocarbons (PAHs) are priority pollutants in drinking and environmental waters. Their mutagenic/carcinogenic potential and ng·L− 1 limits demand methods that are both sensitive and practical. We report a rapid, solvent-sparing workflow coupling stir-bar sorptive extraction (SBSE) to HPLC with fluorescence detection (FLD) for simultaneous determination of six PAHs (fluoranthene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, benzo[ghi]perylene, indeno[1,2,3-cd]pyrene) in drinking water, groundwater, and surface water. SBSE conditions were optimized, and isocratic RP-HPLC achieved baseline resolution within a 26-min cycle using ~ 39 mL solvent (~ 20 samples day − 1). Validation under ISO/IEC 17,025 showed linear calibration (r ≥ 0.99941), limits of detection of 0.4–1.8 ng·L− 1, and matrix-verified LOQs of 1.5–10.9 ng·L− 1. Trueness and precision met predefined criteria across matrices (recoveries 63.3–109.9%; within-laboratory reproducibility ≤ 25% RSD), with expanded uncertainties U(k = 2) ≤ 47.1%. Performance satisfies EU Drinking Water Directive 2020/2184 requirements for benzo[a]pyrene and the regulated PAH sum. By attaining sub-10 ng·L− 1 LOQs with FLD alone and documenting a complete uncertainty budget, this procedure offers a cost-effective alternative to LC–MS/MS for routine compliance and surveillance. The validated SBSE–HPLC–FLD protocol is fit-for-purpose for regulatory laboratories and environmental services requiring sensitive, robust, and scalable PAH determination across diverse water matrices.