BEIJING (AP) -- Air quality in Beijing, notorious for its smoggy sky, improved during the first six months of 2015, the city government said.
The concentration of PM 2.5 - tiny airborne particles that are particularly harmful to human health - dropped by 15.2 percent from a year earlier to an average of 77.7 micrograms per cubic meter during the first half of the year, the government said, citing data from the municipal environment protection bureau.
However, that level remains considerably higher than the 10 micrograms per cubic meter annual average considered safe by the World Health Organization.
The city government said the amounts of sulfur dioxide, nitrogen dioxide and PM 10 particles also decreased.
Chinese officials have vowed to clean up Beijing's foul air. Authorities have closed some polluting factories in the region, stepped up law enforcement of polluting industries and limited carbon emissions.