BACKGROUND: An epidemic of asbestos-related disease is ongoing in most industrialized countries, mainly attributable to past occupational exposure but partly due to environmental exposure. In this perspective, the incidence of pleural mesothelioma close to a former asbestos-cement plant in a national contaminated site was estimated. METHODS: The census-tracts interested by atmospheric dispersion of facilities in the contaminated site were identified. Two subareas with different estimated environmental asbestos impact were distinguished. An ecological study at micro-geographic level was performed. The standardized incidence ratios (SIR) for study area and the two subareas, in comparison with region and municipality were computed. The standardized incidence rate ratio (IRR) between the two subareas was computed. RESULTS: Mesothelioma incidence in the study area was increased: 46 cases were observed with respect to 22.23 expected (SIR: 2.02). The increase was confirmed in analysis considering only the subjects without an occupationally exposure to asbestos: 19 cases among men (SIR = 2.48; 95% CI: 1.49-3.88); 11 case among women (SIR = 1.34; 95% CI: 0.67-2.40). The IRR between the two subareas is less than one in overall population considering all age-classes and of 3 fold (IRR = 3.14, 95% CI: 0.65-9.17) in the age-classes below 55 years. CONCLUSIONS: The findings indicate an increased incidence of pleural mesothelioma in the neighbourhood of asbestos-cement plant, and a possible etiological contribution of asbestos environmental exposure in detected risks.