A health hazard, specifically the leukaemia risk, is evaluated from different sources of benzene exposure with relation to a population living in an urban area of Italy. The population exposure is calculated for a reference year by sex and lifestyle, with respect to smokers and non smokers. Potential health risk is therefore quantified by means of mathematical models and the relative significance of the different sources is described. The results of the analysis are useful for the identification of appropriate risk reduction strategies to minimize exposure, in particular when resulting from lifestyle and personal activities.