BEIJING:- China’s air quality improved across the country in 2017, the environmental protection ministry said Thursday, after the problem was so dire in previous years that some periods were dubbed an “airpocalypse”. The average level of PM2.5 particles - which penetrate deep into the lungs - in 338 cities stood at 43 micrograms per cubic metre last year, falling 6.5 percent year-on-year, according to a ministry statement. The World Health Organization recommends a maximum average exposure of 25 micrograms per cubic metre in a 24-hour period.–AFP