Beijing

The proportion of hazardous metal toxins in PM 2.5 in Beijing have reportedly decreased for the past three years, which experts lauded as the initial achievement of the city's anti-smog measures but netizens ridiculed.

The ratios of three carcinogenic heavy metals - arsenic, aluminum, and cadmium - in the PM 2.5 have dropped by 85.9 percent, 48.9 percent and 40.7 percent respectively, according to a report jointly released by Pan Xiaochuan, a professor from the School of Public Health with Peking University, and an environmental organization, Digital Daily reported, without giving the name of the organization.

The newspaper said Beijing has closed three coal power plants since 2014, and the density of the sulfur dioxide discharged from coal burning dropped 49 percent compared with the data from 2013, citing data from the report.

Dong Liansai, director of the environmental organization, was quoted by the Digital Daily as saying that the decrease of the density of arsenic and sulfur dioxide shows the government's measures to cut air pollution are working.

However, Dong noted that there are still other carcinogenic substances in the PM 2.5 that are harmful to human health.

But Net users were not so impressed by the decrease of hazardous substances in the air with some mocking that the smog has now become "environmental-friendly."

"I didn't know the smog was classified as 'normal smog' and 'green smog'," one Net user posted on Sina Weibo on Tuesday. Another Net user wrote that "it seems the conception of 'healthy smog' will become popular."