An aerial view of Taicang in Jiangsu province [Photo/WeChat ID: taicangdaily]

Ozone pollution is forecast to be the biggest contributor to Taicang's recent air quality deterioration, local media reported on Aug 18.

It was also the only major pollutant for mild or moderate air pollution that occurred in many other parts of the city through July, according to the environmental authority of Taicang.

Last month, only 61.3 percent of the days boasted good air quality and ozone was the major pollutant for the other 12 days.

Ozone occurs in both the troposphere, the layer closest to the Earth's surface, and the stratosphere, the layer that extends upward from about 9 to 48 kilometers.

In the troposphere, the gas could trigger a variety of health problems, particularly for children, the elderly, and people troubled by lung diseases.

Taicang will roll out new guidelines to control ozone pollution, which has been rising steadily since 2013, by stepping up controls of nitrogen oxide and volatile organic compounds.

The city will launch a campaign to crack down on companies violating gas emission regulations to ensure good air quality throughout the year.