Long-term exposure to fine particulate matter (PM2.5) is associated with respiratory and cardiovascular diseases. PM2.5 consists of a complex mixture of organic and inorganic species, with toxicity varying based on its chemical composition, sources, and physicochemical properties. This study investigates the oxidative potential (OP), cellular oxidative stress, and inflammatory response induced by five distinct chemical fractions of urban PM2.5: water-soluble tota