The names of the most polluted cities in the country were released Tuesday.

China's environmental watchdog released the list for the first time as part of efforts to improve air quality across the country.

North China's Shanxi Province, well-known for its coal industry, stood out with three cities included on the black list: Linfen, Yangquan and Datong.

The others are Shizuishan in Ningxia Hui Autonomous Region, Sanmenxia in Henan Province, Jinchang in Gansu Province, Shijiazhuang in Hebei Province, Xianyang in Shaanxi Province, Zhuzhou in Hunan Province and Luoyang in Henan Province.

Beijing, which has seen improved air quality, was still listed at number 28 out of 113 cities in the list.

Shi Hanmin, chief official of the local environmental protection authority, said Beijing's goal is to have 80 per cent of fairly good or excellent air quality days a year by 2008.

However, current pollution control methods and the size of the capital have kept fairly good or excellent days to 60 per cent a year. The situation is unlikely to improve drastically, the Beijing News reported.

The pollution list was released as part of a report on management and comprehensive improvement of environmental protection in key cities in 2003. The report is delivered every year by the State Environmental Protection Administration.

"These cities must step up efforts to improve air quality," said Wang Jirong, deputy director of the administration.

Cities cited with an over- concentration of nitrogen dioxide (NO2) in the air include Nanjing, Guangzhou and Xi'an. They were asked to develop effective pollution-reduction plans, she said.

Though overall environmental quality has improved steadily in the past year, Wang said, environmental infrastructure in 47 key cities has to be strengthened.

The report said provincial capitals, including Changchun in Northeast China's Jilin Province and Wuhan in Central China's Hubei Province had poor sewage disposal systems while others were struggling with consumer waste.

The cities with most advanced environmental infrastructure are Dalian, Yantai, Shenzhen, Zhuhai, Haikou, all of which are coastal cities.

The top five environmentally friendly cities are all from South China and they are Haikou in Hainan Province, Zhuhai and Zhanjiang in Guangdong, Guilin and Beihai in the Guangxi Zhuang Autonomous Region.

Forest areas grew 0.68 per cent nationwide, faster than in 2002, according to the report.

The average environmental investment also saw an increase of 0.14 per cent, accounting for 2.43 per cent of the gross domestic product.

The administration began to test the environment in cities around the country in 1989. The test looks into areas such as pollution reduction, infrastructure construction and environmental management.

All together 608 cities, or 91 per cent of the total number of cities in the country, have been tested.