The density of major air pollutants in Chinese cities saw a decrease in February, data from the Ministry of Ecology and Environment showed.

For the 339 cities monitored by the ministry, the average density of PM2.5, a key indicator of air pollution, decreased by 2.2 percent year on year to 45 micrograms per cubic meter, according to the ministry.

The average density of PM10 went down 8.6 percent from the same period last year to 64 micrograms per cubic meter, and the figure for sulfur dioxide fell 10 percent to 9 micrograms per cubic meter.

Among the 168 key cities monitored by the ministry, Lhasa, the capital of southwest China's Xizang Autonomous Region ranked top in terms of good air quality last month. It was followed by Haikou in south China's Hainan Province and Huizhou in south China's Guangdong Province.