China’s new national air quality standards set in March by the environment ministry require annual fine particulate matter (PM2.5) limits to fall from 35 to 30 micrograms per cubic metre (μg/m³) by 2030, and further to 25 μg/m3 after 2030.
Average PM2.5 concentration stood at 28 µg/m³ in 2025, within the current national standard of 35 µg/m³, but still six times higher than the World Health Organisation’s guideline. The revised standards nonetheless bring China closer to international benchmarks.
In 2021-2025, China achieved double-digit PM2.5 reductions nationwide and even larger declines in key northern regions. Yet the central task has shifted from cutting pollution quickly to sustaining improvements. The main emerging challenges are volatile organic compound (VOC) emissions, mainly from cars and industry, as well as increased coal use in the chemicals industry and widening regional disparities.
With air pollution control now entering what policymakers describe as the “deep water” stage, further progress will depend less on rapid, large-scale conventional reductions and more on structural changes. This particularly means electrifying heavy industry and the transport sector, supported by a growth in clean power generation and a reduction in coal consumption.
PM2.5 reductions were closely linked to a combination of economic restructuring and rapid clean-energy deployment, rather than to air-pollution controls alone.
China’s real-estate sector entered a prolonged downturn, translating into sustained declines in construction-related industrial output. In 2025, production of crude steel, cement and flat glass fell by 4.4 per cent, 6.9 per cent and 3.0 per cent respectively, cutting emissions from some of China’s most pollution-intensive sectors.
At the same time, fossil-fuel power generation declined by 1 per cent in 2025 due to the rapid growth in clean energy, leading to further reductions in air pollutant emissions from the power sector.
The achievements are commendable, but greater challenges lie ahead.
Pollution fell structurally but unevenly
Beijing and Shanxi (part of the Fen-Wei Plain) recorded the strongest air quality improvements in both the short and long term. But elsewhere progress has been less even.
In 2020, the provinces with the highest absolute PM2.5 concentrations were largely in the Beijing-Tianjin-Hebei region, Xinjiang and other parts of the east coast. Since then, however, the pollution pattern has shifted west and south.
PM2.5 levels have risen across parts of central and western China, and pollution rebounded in north-eastern China, Xinjiang and parts of the south. Several southern inland provinces have also moved into the top ten.
These divergences reflect different economic trajectories. In 2025, Beijing and parts of the Fen-Wei Plain saw some of the steepest declines in construction-related industrial output, including cement, crude steel and pig iron, alongside substantial reductions in thermal power generation.
While in north-eastern China and Xinjiang, rising PM2.5 levels were likely associated with increased chemical production, steelmaking and thermal power generation. In southern provinces such as Guizhou and Guangxi, expansion in chemicals and metals production has also pushed PM2.5 levels higher.
The coal problem: decreased demand from the power sector offset by chemicals
Coal supply increased by 23.8 per cent between 2020 and 2025, driven by rising power demand, policy signals to expand coal reserve capacity, and support for the development of large coal bases which integrate mining with coal processing and increasingly coal-to-chemical projects. However, coal output growth started to slow down from 2024, to 1 per cent, as clean-energy deployment accelerated.
While coal use for power generation has moderated, the chemicals sector has emerged as the fastest-growing source of coal demand. Consumption in the chemicals industry rose by 12.1 per cent year on year in the first half of 2025.
The reduction of coal consumption in the power sector and the steel and cement industries, amid the expansion of coal-to-chemicals, has reshaped the sources of particulate pollution. Between 2020 and 2024, the share of PM2.5 emissions from the power sector declined from 13 per cent to 5 per cent, while emissions from coal mining rose sharply, from 18 per cent to 40 per cent.
And absolute PM2.5 emissions from coal mining grew by 62.9 per cent. This points to a growing upstream pollution challenge, even as emissions from traditional downstream sources fell alongside the contraction of the real-estate sector.
Transport and VOCs: The weakest link
While industrial emission cuts drove down a number of air pollutants, progress in the transport sector has been more mixed. A group of even less visible pollutants continued to rise, signalling the hidden challenge to further improve air quality.
VOCs emissions rose by 7.9 per cent between 2020 and 2024, driven primarily by growth in transport-related emissions and continued increases from industrial sources, exposing a critical weakness in the current policy mix. In 2024, hydrocarbons from gasoline vehicles accounted for 84.5 per cent of total vehicle-related VOC emissions, underlining the central role of gasoline vehicle control and electrification.
Gasoline vehicles are now the dominant source of transport-related VOCs, while diesel vehicles remain a major source of nitrous oxides and particulate matter. Plug-in hybrid vehicles operating with depleted batteries exhibit emissions profiles similar to conventional gasoline cars, limiting their benefits for VOC control.
By 2025, China’s new-energy vehicle stock had expanded to around 44 million vehicles, and such vehicles accounted for more than half of new car sales.
Yet they still represented only about 12 per cent of all vehicles on the road, meaning that the emissions profile of the transport sector continues to be shaped primarily by gasoline vehicles. VOCs are also key precursors of secondary PM2.5. So weak VOC control increasingly undermines progress on both of China’s main air pollutants – PM2.5 and VOCs.
Industrial VOC emissions rose by 2.4 per cent from 2020 to 2024, driven mainly by expansion in the chemicals sector. However, controls are expected to be strengthened going forward by recent policy interventions. These include ultra-low emission standards for the coking industry, issued in late 2024, and pilot VOC taxation, authorised in 2025.
As VOC control has emerged as one of the clearest unresolved challenges, further progress will depend on the continued scaling up of electric vehicles to change the structure of the vehicle fleet, alongside tighter regulation of VOC-intensive industrial activities, particularly in the chemicals sector.
Deeper structural reductions
China’s air quality gains were driven mainly by structural economic shifts, notably the downturn in construction-related heavy industry and the rapid expansion of clean energy.
As overall emissions decline, the focus of air quality management is shifting toward how remaining sources are addressed and how reductions are sustained.
With pollution trends diverging across regions, particularly where industrial activity is expanding, meeting the new air quality standards will depend on locking air pollution control into the next phase of structural change, from continued coal phase-down to deeper electrification in sectors such as chemicals and steel, and cleaner development of emerging industries, including vehicles and clean energy.
Together, these trends indicate that future air quality gains will depend less on short-term measures and more on embedding cleaner energy and electrification into China’s development model. How effectively coal is phased out, and how rapidly renewables are deployed to support both electricity supply and industrial demand, will be central to determining whether improvements can be consolidated as the new standards come into force.
A note on data sources:
Measured air quality data is compiled from China’s national real-time ambient air quality information platform and the Ministry of Ecology and Environment’s monthly and annual reports. Weather-adjusted air quality indicators are produced using the Centre for Research on Energy and Clean Air’s de-weathering algorithm. Data on industrial output and power generation are drawn from publicly available Chinese government sources.
This article was originally published on Dialogue Earth under a Creative Commons licence.
