Risk of non-Hodgkin's lymphoma and residential exposure to air pollution in an industrial area in northern italy: A case-control study

The aim of this study was to evaluate the risk of non-Hodgkin's lymphoma (NHL) in an adult population residing in an area in northern Italy exposed to industrial air pollution from a big power plant, a coke oven, 2 chemical factories, and some minor plants. The design was a populationbased case-control study and information about residential history and the main risk factors for NHL was obtained interviewing 133 cases and 279 controls using a structured questionnaire. Three exposure categories (heavy, moderate, and slight) were defined on the basis of the location of the major facilities with respect to the subject residence. NHL risk was not associated either with location or duration of residence in the heavily polluted area. However, the unavoidable limitations of this study prevent us from drawing definitive conclusions.