Chinese cities suffered from more days of air pollution in January, with northern areas being the worst affected, official data showed Tuesday.
Last month, the 338 cities monitored by the Ministry of Environmental Protection (MEP) enjoyed good air quality on 60 percent of days, down 6.7 percentage points from the same period last year.
The average density of PM2.5, fine particulate matter that causes smog, came in at 78 micrograms per cubic meter, up 14.7 percent.
In the Beijing-Tianjin-Hebei region, the share of days with good air quality during the month was merely 36.2 percent, a year-on-year drop of 19.6 percentage points, according to the MEP.
PM2.5 density in Beijing surged 70.6 percent to 116 micrograms per cubic meter during the month.
The city of Haikou in Hainan Province continued to have the cleanest air out of the nation's 74 major cities, while Shijiazhuang in Hebei Province was the worst polluted.
January's air pollution was partly due to the Lunar New Year custom of setting off fireworks and crackers for celebration, which had led to a surge in the density of PM2.5.
The MEP on Sunday named and shamed several cities in north China for not doing enough to cope with air pollution.
In an inspection on 18 cities in the Beijing-Tianjin-Hebei region and neighboring areas, the MEP found several problems in their response to air pollution, including inadequate planning and poor implementation.
