Analytical development of a multi-residue extraction method for 285 polar and non-polar organic pollutants in passive...

We present a novel analytical protocol that combines accelerated solvent extraction (ASE) and solid-phase extraction (SPE) for the quantification of 285 organic air pollutants adsorbed onto a passive sampler composed of N-doped carbon-coated silicon carbide foam (NMC@SiC). The method simultaneously covers six polar and non-polar compound classes: 24 amines, 35 organic acids, 127 pesticides (including volatile, semi-volatile, and organochlorine pesticides, OCPs), 61 phenols, 16 polycyclic aromatic hydrocarbons (PAHs), and 22 polychlorinated biphenyls (PCBs). ASE parameters (cycle number and extraction conditions) and SPE parameters (elution solvents, loading volumes, and cartridge types) were systematically optimized. Method validation confirmed excellent linearity (r² > 0.99 within 1-1000 ng), sensitivity, robustness (recoveries exceeding acceptable thresholds), and precision (relative standard deviation <30 %). Limits of quantification (LOQs) were remarkably low, particularly for PAHs, PCBs, OCPs, non-volatile pesticides, and carboxylic acids, with median values of 1.2, 0.4, 0.7, 0.08, and 1.7 pg m⁻³, respectively. Higher LOQ medians were observed for amines (5.9 pg m⁻³), phenols (4.1 pg m⁻³), semi-volatile pesticides (23.5 pg m⁻³), and dicarboxylic acids (23.2 pg m⁻³). Recovery analysis showed that approximately 60 % of the target compounds achieved recoveries above 60 %, 20 % between 60 and 80 %, and 15 % between 30 and 60 %. Precision, evaluated through intra- and inter-day variation, remained below 30 % for most compounds, except for a few amines, phenols, and pesticides, which reached up to 36 %. Application of the method to five urban air samples collected in the Strasbourg area demonstrated its broad detection capability, with most compounds quantified at ultra-trace levels. Overall, this analytical protocol provides high sensitivity, broad chemical coverage, and strong robustness, making it highly suitable for comprehensive monitoring of airborne organic pollutants in complex environmental matrices.