PM2.5 density drops in major Chinese cities

The density of PM2.5, or particles smaller than 2.5 micrometers in diameter, has dropped year on year in the first 74 Chinese cities to adopt the new air quality index, Environment Minister Zhou Shengxian said on Thursday.

In the first five months of this year, the PM2.5 density in these cities dropped 7.5 percent from the previous year, while the average PM10 density was reduced by 6.9 percent, according to Zhou.

The average PM2.5 density in the 13 major cities in the Beijing-Tianjin-Hebei area decreased by 7.6 percent. PM2.5 density in cities in the Shanghai-centered Yangtze River Delta only decreased 1.4 percent.

The degree of pollution has decreased, and the duration and area affected by pollution have all been reduced, Zhou said.

China has started to implement a revised air quality monitoring standard, which adds indices for ozone, carbonic oxide and PM2.5. The standard was first rolled out in 74 cities, including the municipalities of Beijing, Shanghai, Tianjin and Chongqing and all provincial capitals in late 2012, and the country is gradually expanding the standard nationwide.

The government aims to cut the density of PM2.5 by about 25 percent from 2012 levels in Beijing and surrounding provincial areas by 2017.

Zhou said the environmental burden is still heavy despite the progress, and the ministry will intensify punishment for enterprises violating the environment protection law and strengthen inspections on implementation of the new standard.