Picture of Better Health: Prioritizing Air Pollution Control in China

Article excerpt

China's Yangtze River Delta is one of the most heavily polluted and densely populated areas of the world, with some districts of Shanghai exceeding a population density of 40,000 people/[km.sup.2]. Annual average concentrations of fine particulate matter ([PM.sub.2.5]), microscopic airborne particles that cause heart and lung damage, are estimated to vary from 14 [micro]g/[m.sup.3] in the cleanest areas to 133 [micro]g/[m.sup.3] in the dirtiest. By contrast, most major cities in the United States have annual average [PM.sub.2.5] levels between 7 and 20 [micro]g/[m.sup.3]. Yet a new study suggests regions as highly polluted as the Yangtze River Delta can clear the air and in the process save thousands of lives by adopting common pollution-control technologies [EHP 118(9): 1204-1210; Zhou et al.].

The study is believed to be one of the first risk assessments of a developing country using the Community Multiscale Air Quality (CMAQ) modeling system. Although CMAQ is widely used in the United States, most developing countries lack the exhaustive data on emissions, pollutant monitoring, and weather conditions needed to make accurate predictions. The research team capitalized on emissions data from China that NASA estimated using satellite measurements during a 2006 study of intercontinental pollution drift.

The researchers examined emissions of sulfur dioxide ([SO.sub.2]), nitrogen oxides ([NO.sub.x]), volatile organic compounds (VOCs), and [PM.sub.2.5], focusing on the effect of these pollutants on [PM.sub.2.5] and ozone concentrations. Ozone is a gas formed when NO and VOCs in the atmosphere react in sunlight. …