Zhengzhou, Henan province, which is among the 10 Chinese cities with the worst air pollution in 2015, has begun imposing heavy fines on its districts and counties of 500,000 yuan ($77,300) for each unit per cubic meter.

The city is among an increasing number that are using financial pressure to control air pollution.

The provincial capital's interim measures to improve air quality, which took effect on April 1, set an annual ceiling for PM2.5 of 79 micrograms per cubic meter or less on average, and a PM10 target of 150, the city government said.