Byssinosis In Workers Research Articles

Prevalence of respiratory diseases in the textile industry. Relation with dust levels

Many workers in the textile industry have respiratory symptoms that are related to their work environment. In this study we observed the dust level conditions of eleven textile industries of the North of Portugal. The dust levels determined were between 0.1 mg/m3 and 1.25 mg/m3, in many cases above the Portuguese standard levels of exposure (VLE). For these dust levels we found a prevalence of 23% of workers with respiratory symptoms with occupational characteristics in 10.8%, and 5.7% presenting byssinosis. Workers exposed to cotton fibres in spinning areas have the highest prevalence of symptoms, and reduction of the FEV1. These characteristics were related to dust levels and were higher in the initial phases of the spinning processes. We found no cases of byssinosis in workers exposed to synthetic fibres, or in workers from weaving areas. Smoking habits were related to the reduction of the FEV1, and severity of respiratory illness but not to the presence of byssinosis.

Byssinosis in Belfast ropeworks: an historical note.

The occurrence of byssinosis in workers handling hard fibres at the Belfast ropeworks in 1961 is described. The prevalence in 282 workers in two mills was 2.8% (one man, seven women). It was much less common than in workers exposed to the soft fibres of hemp and jute and flax where the prevalence in 186 workers so exposed was 15% (28 cases). These findings are discussed.

Pulmonary Function Response to Dust from Standard and Closed Boll Harvested Cotton

Although the characteristic feature of byssinosis in workers exposed to cotton dust is the symptom of chest tightness occurring on the first day back to work after an absence, changes in objective measurements of pulmonary function also have been demonstrated. Not all byssinotic patients show objective changes, but as a group they tend to have greater reductions in the FEV1 over the workshift than asymptomatic workers and those not exposed to cotton dust.1 The prevalence of symptoms and decrements in pulmonary function increase with increasing dust exposure,2 but even high dust levels may be associated with a low prevalence of byssinosis if the dust is of low “biologic activity.”3 Reduction of the biologic activity of the dust may be important, since extrapolation of dose-response curves suggests that even low levels of dust may be associated with symptoms of byssinosis in some workers.

Effects in man and rabbits of inhalation of cotton dust or extracts and purified endotoxins.

Cavagna, G., Foa V., and Vigliani, E. C. (1969). Brit. J. industr. Med., 26, 314-321. Effects in man and rabbits of inhalation of cotton dust or extracts and purified endotoxins. The incidence of byssinosis in workers in a cotton card-room, where the airborne concentration of bacterial endotoxins was 7·2 μg./m. 3 , was 32%; and 47% in a hemp card-room where the endotoxin concentration was 8·7 μg./m. 3 ; no cases were observed among workers exposed to only traces of endotoxins. The effect of the inhalation by aerosol of purified Escherichia coli endotoxin on F.E.V. 1·0 and F.V.C. was studied in normal subjects and in patients with chronic bronchitis. A significant reduction in F.E.V. 1·0 lasting more than 6 hours was observed in two out of eight normal subjects, in one out of three subjects with chronic bronchitis inhaling 80 μg. endotoxin, and in one out of four subjects with chronic bronchitis inhaling 40 μg. endotoxin. These results show that the inhalation of bacterial endotoxin can produce, in some individuals, changes in F.E.V. 1·0 similar to those experienced on Mondays by some card-room workers. A study of the mechanism of pathogenesis of inhaled bacterial endotoxins was carried out on rabbits subjected for 20 weeks to aerosols of purified E. coli endotoxin (20 μg./day) and cotton extract (2 mg./day). This treatment produced patterns of bronchitis: i.e., a increase in the respiratory tract fluid with increased protein content and characteristic histopathological changes. The bronchitis occurred after the appearance of cross-reacting circulating antibodies against E. coli endotoxin and cotton extract. These antibodies were detected with the haemagglutination tests after the first three weeks of treatment, and in subsequent weeks reached progressively higher titres, up to a maximum of 1:512. A challenging aerosol of 0·1 mg. E. coli endotoxin in two rabbits and 10 mg. cotton extract in another two of the rabbits treated as above produced a marked increase in pulmonary resistance lasting more than two hours. In control rabbits a challenging aerosol of 1 mg. endotoxin or 100 mg. cotton extract caused only a moderate increase in pulmonary resistance, which returned to normal in less than one hour. It may be concluded that the repeated inhalation of endotoxins induces in rabbits a state of hypersensitivity and at the same time the appearance of inflammatory reactions in the bronchi and alterations in the mechanical properties of the lung. These changes may be significant in the pathogenesis of byssinosis.