China has released its Bulletin on the Second National Census on Pollution Sources. The survey was conducted by 15 ministerial departments over three years and aimed at identifying pollution threats throughout the country.

The once-a-decade census reveals the scale, structure and distribution of the country's current pollution sources.

"It has an important role in winning our tough battle against pollution and it will support the protection of China's ecology and environment," said Zhao Yingmin, vice minister of ecology and environment.

The census established more than 1,800 database tables and collected over 150 million items of basic data.

It shows that by the end of 2017, there had been over 3.58 million various pollution sources in China.

Over 44 percent of them are from major industries and almost 53 percent are from five provinces in eastern China.

It also shows changes at facilities for wastewater treatment, desulfurization and dust extraction which had 2.4, 3.3 and five-fold increases respectively.

"After three years, the mission was completed with the dedicated efforts of hundreds of thousands of census takers and the full coordination from the vast respondents. And time limits, heavy tasks and technical challenges were overcome," Zhao stressed.

The official also warned that the major pollutants are still at high levels and there needs to be further improvement. And he calls for more awareness of the environment.

"The outbreak of COVID-19 also reminds us that the whole society needs to advocate for a green and healthy lifestyle and take more care of the environment," said Zhao.

China published the results of the first such national census in 2010. Since then, more tough measures began to take effect to control and prevent various types of pollution. And the census now will give further impetus to those efforts.

Beijing says that from the census, there appear to be a large number of environmental professionals and volunteers. And the country hopes to raise awareness of the need to clean up its air, water and soil in the days to come.