A survey of respiratory disease in cotton operatives. I. Symptoms and ventilation test results.

42-47. Between 1966 and 1968, 2 316 operatives were examined in the blow and card rooms of the south-east Lancashire coarse cotton industry. Between 1968 and 1970, a second survey of 2 556 operatives was carried out including 886 of the previous group and also operatives in fine and coarse cardrooms, in ring and winding rooms, and operatives in other parts of the country who were not examined previously. Symptoms and ventilatory changes of byssinosis were found in operatives in all mills except the two fine cotton mills. Some operatives with less than 10 years' exposure were classified as byssinotic, including 14 in the first survey and 17 in the second who had had less than five years' exposure. These operatives were found in all types of work room. The 886 operatives examined on two occasions showed a greater deterioration in ventilatory function than a local control population. Even symptom-free operatives showed a 10% excess in the rate of deterioration of FEV with age. But neither the ventilatory tests nor the symptomatic enquiry were of value in predicting the rate of deterioration between the two studies.