The southwestern Chinese city of Chengdu has seen the concentration of major air pollutant PM2.5 fall 42.3 percent in four years.
The reading of PM2.5, smaller airborne particles more damaging to health, stood at 56 micrograms per cubic meter in 2017, down by 10.2 percent year on year, said Zhang Jun, head of the Chengdu Municipal Bureau of Environmental Protection Sunday.
A total of 235 days had good air quality in 2017 with air quality index (AQI) below 100, Zhang said.
The bureau issued 3,415 administrative penalties against environmental violations and levied fines of 200 million yuan (31.6 million U.S. dollars) last year, up 231 percent and 413 percent, respectively.
Despite the efforts, the air quality in Chengdu, capital of Sichuan Province, ranked 54th among 74 major cities nationwide.
To further improve the air, authorities will tackle industrial pollution by phasing out coal-fired boilers and closing small polluting firms, and as well as limiting vehicle emissions and construction dust.