Asbestos has been widely used in Italian thermoelectric power plants and instances of exposure to workers have been documented in a variety of jobs. Preventive measures were put into effect only in the late 1970s. We report here on four mesothelioma cases among workers of three Italian power plants where cohort studies were carried out, and on three additional cases recorded by a systematic survey carried out on this neoplasm in Tuscany. When the data of the cohorts sources are merged, a significant excess of lung cancer is also evident. Even without a quantitative assessment of exposure, this report shows the importance of asbestos risk in thermal power plants. The risk appears not to be restricted to any particular category of workers.