Please read Dr. Kipen’s article in the Journal of Journal of Thoracic Disease titled, “Respiratory health, children’s lung function, and air quality in four Chinese cities: two snapshots in 1993-1996 and 2017-2018“.
From 1993 to 1996, the original Four Chinese Cities (4CC) study was conducted to examine the effects of outdoor and indoor air pollution on respiratory health symptoms and illnesses and lung function growth in elementary school children. Chongqing, Guangzhou, Lanzhou, and Wuhan were selected, as these cities had distinct pollution sources and provided a large gradient in outdoor levels of particulate matter (PM10, PM2.5) and gaseous pollutants (SO2 and NO2). At the time, characteristic sources were sulfur-rich coal combustion in Chongqing, motor vehicular traffic in Guangzhou, and an oil refinery coupled with coal combustion as well as sand/road dust in Lanzhou, whereas Wuhan did not exhibit a single dominant source as in the other three cities. To read the full article.