Major impacts of air pollution are lung diseases such as granulomatous diseases and mainly sarcoidosis. Understanding the respective role of inorganic / nanoparticles and genetic background in these chronic diseases is a major challenge for the management of patients and prevention strategies. Granulomas are characterized by giant epithelioid and multinucleated cells, reflecting a severe disturbance in immunological pathways induced both by toxic exposure and genetic predisposition. Previous studies demonstrated that professional environmental context and acute exposures (the World Trade Center disaster) to micro/nanoparticles have a pathogenic impact with a sharp increase in sarcoidosis. Sarcoidosis is a multifactorial disease occurring in a genetically vulnerable context. Many gene variants have been linked to an increased odds-ratio of the disease, such BTNL2, CCDC88B, ANNEXIN A11 involved in regulation of T-cell activation and maturation pathways. We have contributed since 2008 to a national cohort (GSF, 28 centers) of ≈ 800 sarcoidosis patients with familial and sporadic presentation of the disease. This collection has been an exceptional (and worldwide unique) tool for the implementation of an exhaustive clinical database on sarcoidosis, modelling of disease evolution and identification of clinical / genetic criteria differentiating sporadic and familial forms.