Discrepancies in the study of byssinosis in China.

The existence of byssinosis in China was first reported in 1964. Detailed studies only started in the late 1970s and early 1980s. The work of the WHO study group as edited by the Technical Report Series no. 684, "Recommended health-based occupational exposure limits for selected vegetable dusts," promotes the further study of occupational disease in China; a few points need further discussion. The word byssinosis translated in Chinese is misleading as to the real pathogenesis of the disease. Some still believe cotton dust causes interstitial fibrosis, while the majority of researchers agree with the WHO study group. A poorly designed animal model may have led to the (incorrect) conclusion that dust from carding room is toxic if it is injected intratracheally. The reasons for the controversy in the prevalence of byssinosis in different reports in earlier years are the different diagnosis criteria and the fact that dust sampling methods were not standardized; pulmonary function tests were not used as a routine index; chronic bronchitis and smoking are now recognized as confounders and should have been considered. This Institute initiated the hygiene standards study on cotton dust and recommended 1 mg/m3 for respirable dust and 3 mg/m3 for total dust. If a reduction in dust levels could prevent byssinosis, it would likely also control the risk factor for developing bronchitis.