Environmental studies and investigations were conducted following reports of a cluster of pediatric cancers in a neighborhood of Vincennes, which is partly located on a former industrial site and near a hospital incinerator. The objective was to assess whether there was an elevated health risk for the local population associated with the presence of one or more potential sources of pollution specific to this urban area. This article describes the approach implemented to address this issue and discusses its innovative aspects. The initial objective and the financial resources committed led to the development of an innovative approach, which proved to be appropriate. It fruitfully combined two approaches, two cultures—"public health" on the one hand and "environment" on the other—which are increasingly converging in the context of new environmental health issues. (R.A.)