Hebei province the most polluted area in China

The Ministry of Environmental Protection has released the third quarter report on the air quality in major Chinese cities. North China's Hebei province remains the most polluted area in the country.

Monitoring data show that 7 of the top 10 most polluted cities are in Hebei province. The remaining three are in Henan province, Shandong province, and Tianjin. Among 74 major cities in China, 70 experienced polluted days in the third quarter, with an average of 29 polluted days.

Ozone and PM2.5, which are major pollutants that come from fossil-fuel burning factories and vehicles, contributed to over 90% of the heavy smog days in all the cities.