Biomass fuels are the probable risk factor for chronic obstructive pulmonary disease in rural South China

Background: There is increasing evidence for a possible association between chronic obstructive pulmonary disease (COPD) and the use of biomass fuels for cooking and heating in developing countries. Data on the prevalence of COPD and objective measurements of indoor pollution from biomass fuel have not been widely available from China. A study was undertaken to investigate the prevalence of COPD in two study communities in Guangdong province in China and to measure the association between COPD and indoor biomass fuel air pollution. Methods: A cluster disproportional random sampling survey was performed in populations aged over 40 years in urban (Liwang) and rural (Yunyan) areas in Guangdong, China. Spirometry was performed in all subjects and a post-bronchodilator ratio of the forced expiratory volume in 1 s to forced vital capacity of