A rapid HPLC–FLD method using a monolithic column for the determination of priority polycyclic aromatic hydrocarbons in bioaccessible PM10 fractions

In recent decades, increasing attention has been given to the fraction of particulate matter (PM)-bound compounds that can be released into simulated lung fluids (SLFs) to estimate their inhalation bioaccessibilities, providing a more realistic basis for assessing potential health risks. In this work, a rapid and reliable analytical methodology was developed for the determination of 14 USEPA priority polycyclic aromatic hydrocarbons (PAHs) in inhalation bioaccessible fractions of PM 10 , obtained using two widely applied SLFs: Gamble's solution and artificial lysosomal fluid (ALF). The proposed approach combines a 1 min vortex-assisted liquid–liquid microextraction (VALLME) with a 10 min HPLC–FLD method using a monolithic column, achieving good precision (RSDs <20%) and acceptable recoveries (80–120%) for most target PAHs in both SLFs. The methodology was applied to 40 urban PM 10 samples collected from two cities in the Southwestern Atlantic European region to assess PAHs inhalation bioaccessibility by in vitro physiologically based extraction tests (PBETs). Bioaccessibilities were systematically higher when ALF was used compared with Gamble's solution (increases of 50 and 30% for 4- and 5-ring PAHs, respectively), also showing an inverse relationship with PAHs hydrophobicity (log K ow ). Negative correlations between 4- and 5-ring PAHs bioaccessibilities and combustion-related PM markers (equivalent black carbon (eBC) and UV-absorbing PM (UVPM)) further suggest reduced PAH release from combustion-dominated PM. These findings indicate that the composition of SLFs influences PAH bioaccessibility. They also highlight the importance of selecting appropriate SLFs according to the targeted lung region, with potential implications for the assessment of inhalation exposure and associated health risks.