Objective: a conceptual and methodological tool is proposed which makes it possible to represent how social, economic and territorial components contribute to the crowding of people within a city. This tool aims to define the areas with health risk due to exposure to gasoline emissions from gas stations. Results: the proposed model can facilitate the targeting, identification and prioritization of zones at risk of environmental contamination by the BTEX released from gas stations in the city. Discussion: when a spatial model of risk includes the number of people going to buildings that generate crowding such as schools and hospitals, the conceptual scope is transcended and methodological and instrumental aspects are offered in order to achieve more robust models that are applicable to other cities. Government agencies should take these results into account when establishing rules, permits and enforcement procedures to reduce environmental contamination. This would thus improve the health conditions in the complex environment of an urban area. Conclusions: Integrated spatial analysis does not solve the complicated social and political negotiations that must take place in any decision making concerning health risk. However, it does improve the ability of scientists and decision-makers to identify, assess, control and reduce the risks associated with emissions from gas stations.