Associations of long-term exposure to ambient fine particulate matter and nitrogen dioxide with lung function: A cross-sectional study in China

•Effects of long-term exposure to air pollution on lung function remains unclear.•We conducted a cross-sectional, multicenter study with 5281 adults from Shanghai, China.•Exposure to ambient PM2.5 and NO2 were negatively associated with lung function decline.•For PM2.5, stronger negative associations were found in the obese and ever-smokers.•For NO2, stronger negative associations were found in the obese, never-smokers and females. Few studies have evaluated the effects of ambient air pollution exposure on lung function, especially in areas with high air pollution levels. To investigate the associations of annual concentrations of particulate matter with diameters