PM2.5 readings of all of the city's 10 monitoring spots and average density of local PM2.5 will be released starting today at the website of Shanghai Environmental Monitoring Center.

The city's latest hourly PM2.5 reading, the latest 24-hour reading and a chart illustrating PM2.5 change within 24 hours will all be available at the website and at Weibo sites of the Shanghai Environmental Protection Bureau and local government. The PM2.5 information on www.semc.gov.cn, and Weibo are in Chinese. Officials said they may offer a bilingual version later.

By the end of this year, Shanghai will officially announce the hourly and daily readings of all six types of pollution - PM10, sulfur dioxide, carbon dioxide, PM2.5, ozone and carbon monoxide - under a national new air quality monitoring standard. The six pollutants will be included in the new air quality evaluation system to better indicate overall air pollution conditions in the nation. Currently, the system includes only PM10, sulfur dioxide and carbon dioxide.

Officials from the Shanghai Environmental Protection Bureau said the days with excellent and good air quality in a year are expected to drop by 10 to 15 percentage points from the current 90-odd percent under the new evaluation system.

"Among the three new pollutants, PM2.5 - "fine" particles measuring 2.5 microns or less in diameter - is the one with the biggest public concern, as it can affect air quality and visibility and explains why what people feel is different from the current air quality evaluation," said Liu Dailin from the bureau.

Since March, Shanghai has released real time PM2.5 figures at two national control spots in Putuo and Zhangjiang.

Shanghai has established 30 PM2.5 monitoring spots, including the 10 national control spots set up under governmental requirements for the city's size and scale of its industry.

Almost all of the 10 national control spots are in downtown areas with dense population, while a spot at Dianshanhu Lake in rural Qingpu is used only as a benchmark for good air quality and not included in the local air quality evaluation.

The Ministry of Environmental Protection issued the new air quality monitoring standard by adding PM2.5, ozone and carbon monoxide to the evaluation system and named Shanghai, Beijing, Tianjin and those in the Yangtze River Delta and Pearl River Delta regions and provincial capitals to be the first in China to adopt PM2.5 and ozone monitoring before year's end.