Background: Human exposure to air pollutants, and specifically to particulate matter (PM) and volatile organic compounds (VOCs), may pose a relevant risk on human health. Aim: To evaluate the personal exposure of adults living and working in Milan (Italy) by environmental and biological monitoring. Methods: Personal exposure of 51 volunteer adults to PM2.5, PM2.5-10 and selected VOCs, including benzene, toluene, ethylbenzene, o-xylene, m+p-xylene, methyl tert-butyl ether, naphthalene, hexane, cyclohexane, heptane, and limonene was assessed along a 24-h period via personal cascade impactors and radial diffusive samplers. Urine spot samples were collected to investigate the corresponding urinary biomarkers. Time-activity patterns were filled in by participants to explore the performed activities. Multiple regression models were applied to investigate the association between personal exposure, biomarker levels, and tobacco smoke, traffic exposure, commuting mode, cooking activities, and personal characteristics. Results: Median personal