Following continuous decreases for almost 10 straight years, the concentration of PM2.5 particulate matter in China declined to below 30 micrograms per cubic meter in 2022, said Huang Runqiu, minister of ecology and environment.

The average PM2.5 density in major cities across the country stood at an unprecedented 29 mcg/cubic m last year, down 3.3 percent year-on-year, he said, as he reported to an ongoing session of the Standing Committee of the National People's Congress on Monday.

The proportion of days with heavy air pollution in the country in 2022 dropped to 0.9 percent, compared with 1.3 percent in 2021.

"It's the first time that the proportion decreased to below 1 percent," the report said.

The minister, however, also noted that efforts to control air pollution still need to be beefed up, especially in some key regions.

On average, cities at the prefecture level and above across the country registered fairly good air quality — considered to be below 100 on a 0-500 air quality index scale — in 86.5 percent of days last year, compared with 87.5 percent in 2021, he said.

The Beijing-Tianjin-Hebei province cluster, the Yangtze River Basin and Fenhe-Weihe Plain saw the proportion of such days drop by 0.5, 3.7 and 5 percentage points, respectively.

Heavy air pollution events still occasionally happened in the Beijing-Tianjin-Hebei province cluster and the Fenhe-Weihe Plain in autumn and winter, he said.