From the definition of silicosis at the 1930 Johannesburg conference to the blurred boundaries between pneumoconioses, sarcoidosis, and pulmonary alveolar proteinosis (PAP).

The 1930 International Labour Office Conference on silicosis in Johannesburg identified silicosis by setting a medicolegal framework to its nosology: as with other occupational illnesses, its medical content was fixed under economic pressure. This article follows a reading of all the proceedings of this conference (debates and reports of experts) to examine their potential impact on the etiology and nosology of other diseases, specifically sarcoidosis and pulmonary alveolar proteinosis (PAP), "idiopathic" diseases in which inorganic particles may be involved. We propose renewed study of the role of inorganic particles in these diseases. To do this, we propose to mobilize detection means such as mineralogical analysis and electron microscopy and in depth interviewing that are currently seldom used in France, in order to establish diagnosis and the potential occupational and environmental origin of these diseases.

Sarcoidosis, inorganic dust exposure and content of bronchoalveolar lavage fluid: the MINASARC pilot study.

Inhalation of mineral dust was suggested to contribute to sarcoidosis. We compared the mineral exposome of 20 sarcoidosis and 20 matched healthy subjects. Bronchoalveolar lavage (BAL) samples were treated by digestion-filtration and analyzed by transmission electron microscopy. The chemical composition of inorganic particles was determined by energy-dispersive X-ray (EDX) spectroscopy. Dust exposure was also assessed by a specific questionnaire. Eight sarcoidosis patients and five healthy volunteers had a high dust load in their BAL. No significant difference was observed between the overall inorganic particle load of each group while a significant higher load for steel was observed in sarcoidosis patients (p=0.029). Moreover, the building activity sub-score was significantly higher in sarcoidosis patients (p=0.018). These results suggest that building work could be a risk factor for sarcoidosis which could be considered at least in some cases as a granulomatosis caused by airborne inorganic dust. The questionnaire should be validated in larger studies. (Sarcoidosis Vasc Diffuse Lung Dis 2018; 35: 327-332).