['Occupational mineral dust exposure is a well-known risk factor for numerous respiratory and systemic diseases. The aim of the present longitudinal study was to assess the influence of work-associated dust exposure on spirometric results. Furthermore, the impact of implementation of stricter limit values for occupational contact with quartz dust on lung function was evaluated.', 'Anthropometric data (age, gender, BMI), smoking behavior, and lung function parameters (FVC, FEV1, MEF50) from 7,204 medical examinations of 3,229 female and male workers during the years 2002-2010 were examined following Austrian standards for occupational medicine and the guidelines of the European Respiratory Society. Analysis of data was performed using models of multiple linear regression.', 'Lung function decrease over time was associated with smoking habits and duration of occupational dust exposure. Specifically, occupational quartz exposure negatively influenced the annual lung function parameters (FVC, -6.68\xa0ml; FEV1, -6.71\xa0ml; and MEF50, -16.15\xa0ml/s, all p\xa0<\xa00.001). Thus, an overadditive effect of smoking and work-related contact with quartz was found regarding decline in MEF50 (p\xa0<\xa00.05). Implementation of stricter occupational limit values for dust exposure resulted in a highly significant deceleration of the annual decrease in respiratory function (p\xa0=\xa00.001).'] Is dust in the air : effects of occupational exposure to mineral dust on lung function in a 9-year study?