As part of the Regional Air Quality Plan, an assessment of the health impacts of urban air pollution was planned for the Chalon-sur-Saône metropolitan area, which is particularly affected by this issue. The methodology for health impact assessments (HIAs), as defined by the InVS, is based on certain assumptions that must be verified before it can be applied. A feasibility study for an HIA was therefore undertaken, concluding that the Chalon-sur-Saône metropolitan area does not fully meet these conditions. The primary obstacle to conducting such a study is the presence of major sources of pollution that prevent the criterion of homogeneous population exposure from being met. Furthermore, the metropolitan area lacks true “background” monitoring stations.