BEIJING, Aug. 20 (Xinhua) -- From January to July, the average concentration of the air pollutant PM 2.5 in Beijing was 29 micrograms per cubic meter, a year-on-year decrease of 21.6 percent, according to a statement of the Beijing Municipal Ecological Environment Bureau on Friday.

In the first seven months of the year, the respective concentrations of PM 10, nitrogen dioxide and sulfur dioxide in Beijing were 53, 21 and 3 micrograms per cubic meter, all reaching their best levels for the period in history.

Beijing will continue strengthening its reduction of PM 2.5 emissions, including volatile organic compounds and nitrogen oxides, and promote the continuous improvement of air quality throughout the year, the bureau said.