干旱区生态环境知识资源中心

Summer and winter surveys of a village in Ladakh have been used to study respiratory illness and domestic pollution from fires in an arid high altitude region of northern India. The prevalence of chronic cough with chronic phlegm rose steeply with age, and was greater among women than men. The percentage of villagers with a forced expiratory volume in one second/forced vital capacity (FEV1/FVC) ratio of less than 65% also rose with age, to include 24% of men and 32% of women over 50 years in the summer survey. Lung function was significantly worse in those reporting chronic cough, independently of age and sex (p < 0.001). Carbon monoxide (CO) measurements were used to assess domestic pollution from fires. Amongst the small minority of smokers (all men) CO in exhaled air was higher than in non-smoking men. In non-smoking men and the women, levels of exhaled CO were very significantly higher in winter than in summer, as were the levels of CO measured in the houses. There was a fall in FEV1 (but not FVC) between summer and winter (p < 0.0001), and an association was found between individual change from summer to winter in exhaled air CO and the individual change in FEV1 (p < 0.01). A significant negative association was found between the winter value of CO in exhaled air and FEV1/FVC ratio in women (p < 0.05), although a similar association in men was non-significant. No significant associations were found between winter pollution levels and the presence of chronic symptoms. During winter, fires without chimneys gave higher levels of house pollution and individual CO in exhaled air than those with chimneys (p < 0.01). It is concluded that domestic pollution is an important contributor to chronic respiratory illness in this community, and that an intervention study is now required to establish the benefits to health of an improved fire design.