Motor vehicle emissions constitute a mixture of different chemicals: volatile organic solvents, polycyclic aromatic hydrocarbons, heavy metals, isocyanates, etc. Drivers working in car cabins are exposed to chemicals deriving from incomplete combustion of fuels, exhaust emissions from working engines and fuel evaporation. Concentrations of these substances are rather low and do not exceed the applicable hygiene standards, but some of them pose, or are suspected to pose, carcinogenic risk. The interaction of chemical substances with human cells and tissues can lead to a number of modifications of metabolic pathways at a cellular level. The first biological mechanism of metabolic modulation is an inflammatory state and oxidative stress generation. The aim of this review is to analyze biomarkers of effect and to assess the hazard of occupational exposure of drivers. Int J Occup Med Environ Health. 2019;32(3):267–80