RESUMO
For this study, ninety two exposed and thirty control workers were chosen randomly from Queisna Menoutex Factory. Each worker was examined using a special questionnaire for respiratory symptoms, personal data, history of exposure, and clinical examination. Spiromelric measurements were done using a compact spirometer. Environmental study revealed levels of acrylic fibres and acrylonitrile vapours lower than their threshold limit values. The results revealed that chronic bronchitis was significantly more prevalent among exposed than the control workers. A significant decrease in mean pre shift spiromelric measurements was found in exposed when compared with control workers. There was a significant association between the time intensity factor [for acrylic fibres and acrylonitrile vapours] and either of the prevalence of other respiratory symptoms or the changes in spirometric measurements for the non smoking exposed workers. Significant increase in the prevalence of respiratory symptoms and a significant decrease in mean pre shift spirometric measurements were found among smoking than among the non smoking exposed workers. The mean post-shift spirometric measurement was significantly lower than that of the pre-shift measurement for all the exposed workers