On October 4, 2016, a local association and a labor union in the municipality of Ottange-Nondkeil alerted the prefect of the Moselle department to the presence of high radon concentrations measured in certain basements of the mining towns within the municipality, as well as to an unusually high number of cancer deaths suspected of being linked to these radon concentrations. Once the health alert was validated, the Grand Est Regional Health Agency (ARS) requested Santé publique France to confirm or refute this suspicion of excess cancer deaths clustered over time and within the territory of this municipality. This summary presents the results of that investigation.