Prevalences of lung diseases in a Chinese greenhouse working population

Rationale: Chinese people are becoming increasingly richer since the adoption of reform and opening up policy in 1979, and the demands for off-season vegetables, cut flowers, mushrooms, and poultry have been soaring since late 1980s, which subsequently led to booming of plastic film greenhouse in China. By now greenhouse farming has become a pillar industry in the northeast region of the country. The long-term exposure to internal greenhouse environments has been considered a risk factor for respiratory symptoms. Estimately the whole country now has about sixty million people exposed to the hazards, roughly the number of England population. We conducted population-based studies of lung diseases in northeast of China, a greenhouse working population, to assess temporal trends in lung diseases prevalence and describe risk factors for lung diseases. Methods: Cross-sectional studies involving a total of 5420 greenhouse farmers working in more than 800 greenhouses in northeast China were performed via stratified-cluster-random sampling. All subjects were interviewed using a uniform questionnaire and underwent pulmonary function tests. Results: The overall prevalence of asthma in Chinese greenhouse farmers was19.19% (1040/5420). The overall prevalence of COPD in green- house farmers was 17.47% (947/5420). Prevalence of famer’s lung among these farmers was 5.68% (308/5,420).Years of age, the area of greenhouses, ventilation duration less than 30 min every time and etc were all identified classic risk factors for lung diseases. Conclusion: In northeast China, lung diseases are highly prevalent among greenhouse farmers, and a number of classic risk factors for lung diseases among greenhouse farmers were identified.