Epidemiological data should support policy makers in their decisions. Misjudgments in data interpretation can justify the preservation of the existing situation and the lack of decision about health and environment safeguard. In the SENTIERI study on Italian polluted sites, women mortality results significantly lower than the regional mean in 11 sites in 44. The authors of this paper think that these data depend on the different impact of pollution on the population of a site, as witnessed by the cases of Brindisi and Manfredonia (Southern Italy). It is now necessary to conduct studies at suburban level integrating mortality data with other available health data.