china air pollution case study

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• Published: 26 July 2021

Drivers of PM 2.5 air pollution deaths in China 2002–2017

• Guannan Geng   ORCID: orcid.org/0000-0002-1605-8448 1   na1 ,
• Yixuan Zheng   ORCID: orcid.org/0000-0002-3429-5754 2 , 3   na1 ,
• Qiang Zhang   ORCID: orcid.org/0000-0002-8376-131X 2 ,
• Tao Xue   ORCID: orcid.org/0000-0002-7045-2307 2 ,
• Hongyan Zhao 1 ,
• Dan Tong   ORCID: orcid.org/0000-0003-3787-0707 2 ,
• Bo Zheng   ORCID: orcid.org/0000-0001-8344-3445 4 ,
• Meng Li   ORCID: orcid.org/0000-0001-5418-9177 2 ,
• Fei Liu   ORCID: orcid.org/0000-0002-0357-0274 1 ,
• Chaopeng Hong   ORCID: orcid.org/0000-0002-8825-9062 2 ,
• Kebin He 1 &
• Steven J. Davis   ORCID: orcid.org/0000-0002-9338-0844 5 , 6 , 2  

Nature Geoscience volume  14 ,  pages 645–650 ( 2021 ) Cite this article

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Between 2002 and 2017, China’s gross domestic product grew by 284%, but this surge was accompanied by a similarly prodigious growth in energy consumption, air pollution and air pollution-related deaths. Here we use a combination of index decomposition analysis and chemical transport modelling to quantify the relative influence of eight different factors on PM 2.5 -related deaths in China over the 15-year period from 2002 to 2017. We show that, over this period, PM 2.5 -related deaths increased by 0.39 million (23%) in China. Emission control technologies mandated by end-of-pipe control policies avoided 0.87 million deaths, which is nearly three-quarters (71%) of the deaths that would have otherwise occurred due to the country’s increased economic activity. In addition, energy-climate policies and changes in economic structure have also became evident recently and together avoided 0.39 million deaths from 2012 to 2017, leading to a decline in total deaths after 2012, despite the increasing vulnerability of China’s ageing population. As advanced end-of-pipe control measures have been widely implemented, such policies may face challenges in avoiding air pollution deaths in the future. Our findings thus suggest that further improvements in air quality must not only depend on stringent end-of-pipe control policies but also be reinforced by energy-climate policies and continuing changes in China’s economic structure.

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Data availability.

The MEIC emission inventory is available from www.meicmodel.org . The dataset generated during this study is available in the figshare repository https://doi.org/10.6084/m9.figshare.14493375 . Source data are provided with this paper.

Code availability

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Acknowledgements

This work was supported by the National Natural Science Foundation of China (41921005 to Q.Z., 41625020 to Q.Z., 91744310 to Q.Z. and 42005135 to G.G.).

Author information

These authors contributed equally: Guannan Geng, Yixuan Zheng.

Authors and Affiliations

State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing, China

Guannan Geng, Hongyan Zhao, Fei Liu & Kebin He

Ministry of Education Key Laboratory for Earth System Modeling, Department of Earth System Science, Tsinghua University, Beijing, China

Yixuan Zheng, Qiang Zhang, Tao Xue, Dan Tong, Meng Li, Chaopeng Hong & Steven J. Davis

Center of Air Quality Simulation and System Analysis, Chinese Academy of Environmental Planning, Beijing, China

Yixuan Zheng

Institute of Environment and Ecology, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen, China

Department of Earth System Science, University of California, Irvine, Irvine, CA, USA

Steven J. Davis

Department of Civil and Environmental Engineering, University of California, Irvine, Irvine, CA, USA

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Contributions

Q.Z. designed the research. Y.Z., G.G. and T.X. performed the research. H.Z., D.T., B.Z., M.L., F.L. and C.H. processed emission data. G.G., Y.Z., Q.Z., S.J.D. and K.H. interpreted data. G.G., Y.Z., Q.Z. and S.J.D. wrote the paper with input from all co-authors.

Corresponding author

Correspondence to Qiang Zhang .

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The authors declare no competing interests.

Additional information

Peer review information Nature Geoscience thanks Rafael Borge and the other, anonymous, reviewer(s) for their contribution to the peer review of this work. Primary Handling Editors: Clare Davis, Rebecca Neely.

Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Extended data

Extended data fig. 1 methodology framework to estimate drivers of china’s pm 2.5 -related deaths..

The MEIC, LMDI, WRF, CMAQ, and GEMM represent the Multi-resolution Emission Inventory for China, the Logarithmic Mean Divisia Index decomposition analysis, the Weather Research and Forecasting Model, the Community Multiscale Air Quality Model, and the Global Exposure Mortality Model, respectively.

Extended Data Fig. 2 Sectoral contributions of major air pollutant emissions in 2002–2017.

Sectoral contributions of SO 2 , NO x , and primary PM 2.5 emissions for 11 sectors in 2002, 2007, 2012, and 2017.

Source data

Extended Data Fig. 3 Changes in PM 2.5 concentrations associated with changes in economic structure in China from 2002 to 2007.

Changes in economic structure majorly increased PM 2.5 concentrations over populated northern provinces such as Hebei, Shandong, and Henan, whose economy highly relies on heavy industries.

Extended Data Fig. 4 Effects of interannual meteorological variations on the national population-weighted monthly mean PM 2.5 concentrations.

Results for the sub-periods ( a ) 2002–2007, ( b ) 2007–2012, and ( c ) 2012–2017, respectively. These results are derived based on simulations of ‘ BASE ’ and ‘ Fix emission ’ scenarios.

Extended Data Fig. 5 Trends in air pollutant emissions and emission removal rates in China over 2002–2017 for (a) SO 2 , (b) NO x , and (c) PM 2.5 .

The blue and orange lines represent actual and estimated unabated emissions, respectively. The red line represents average removal rates.

Supplementary information

Supplementary information.

Supplementary Methods, Figs. 1–6 and Tables 1–7.

Source Data Fig. 1

Source data fig. 2.

Source data.

Source Data Fig. 3

Source data extended data fig. 2, source data extended data fig. 3, source data extended data fig. 4, source data extended data fig. 5, rights and permissions.

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Geng, G., Zheng, Y., Zhang, Q. et al. Drivers of PM 2.5 air pollution deaths in China 2002–2017. Nat. Geosci. 14 , 645–650 (2021). https://doi.org/10.1038/s41561-021-00792-3

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Received : 01 March 2020

Accepted : 07 June 2021

Published : 26 July 2021

Issue Date : September 2021

DOI : https://doi.org/10.1038/s41561-021-00792-3

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Acute Effects of Air Pollution on Human Health in China: Evidence and Prospects

Xiaoming shi.

China CDC Key Laboratory of Environment and Population Health, National Institute of Environmental Health, Chinese Center for Disease Control and Prevention, Beijing, China

The adverse impacts of air pollution on human health have already been a major environmental issue globally, and the challenges are even more severe in China. The World Health Organization (WHO) estimates that 4.2 million deaths annually can be attributed to outdoor air pollution in 2016 ( 1 ). For example, ambient fine particulate matter (PM 2.5 ) has been ranked as the fourth leading risk factor for disease in China ( 2 ). Atmospheric ozone (O 3 ) pollution has demonstrated an increasing trend year by year, and the problem of regional compound pollution has become prominent. Therefore, the acute health hazard of air pollution is a major environmental, medical, and public health burden in China. Clarifying the exposure-response relationships between complex air pollution and population-based acute health effects are great strategic demands. With funding from the National Key Research and Development Program of the Ministry of Science and Technology, the “China Short-Term Health Effects of Air Pollution Study” (China SHEAP Study) project was carried out in 2016 and hosted by the National Institute of Environmental Health (NIEH) of China CDC. This project gathered domestic research and development institutions specialized in national public health and clinical medicine to jointly undertake the task. During the four-year implementation period, the project has achieved a series of innovative findings: 1) it clarified the acute impact of short-term exposure of air pollutants on death of residents and their spatiotemporal distribution characteristics in 106 regions nationwide; 2) it systematically evaluated the acute exposure-response relationships between particulate matter (PM) as well as gaseous pollutants and death, morbidities and symptoms of respiratory and cardiovascular diseases in typically polluted cities from three regions and ten urban agglomerations that conducted national air pollution prevention and control; 3) identified acute health effects of differential particle size and chemical component exposures on children, healthy adults, and patients with cardiopulmonary diseases and determined the particles and their components with major toxicity potency; and 4) conducted intervention research to assess the impact of different intervening measures on acute health hazards of air pollution. Through multilevel and multidimension data as well as the integration of key technologies, this project illustrated the distribution characteristics of population-based acute health risks of complex air pollution and established a dataset for complex air pollution and health as well as a data integration platform.

In this special issue, we invited colleagues and collaborators involving in the China SHEAP study project to report their latest findings. For example, Niu et al. examined the associations between air pollutants with daily hospitalizations and outpatient visits of chronic obstructive pulmonary disease (COPD) and asthma within 5 Chinese cities. The results showed that air pollutants were significantly related to the increasing outpatient and hospitalization rates of chronic respiratory diseases ( 3 ). Liu et al. assessed the associations of short-term PM 2.5 mass exposure with several ambulatory blood pressure (BP) monitoring indicators from a panel study conducted in Beijing, Shanghai, Wuhan, and Xi’an. The results indicated that short-term PM 2.5 exposure was significantly associated with BP elevations ( 4 ). Xia and Niu et al. evaluated the associations between personal O 3 exposure and biomarkers of inflammation, oxidative stress, and mitochondria oxidative damage among 43 college students in Shanghai. They found that short-term exposure to low concentrations of O 3 was significantly associated with vascular inflammation, lipid peroxidation, and mitochondrial oxidative damage ( 5 ). By conducting a randomized crossover study in Beijing, Zhang et al. found that short-term co-exposure to multiple ambient pollutants could disturb the cardiac autonomic function, and that black carbon (BC) and noise were the two pollutants with the greatest contribution ( 6 ). Finally, Chen et al. applied two time-series approaches with a two-stage statistical analysis to estimate whether and how temperature-modified acute effects of O 3 affected mortality in Beijing Municipality, Tianjin Municipality, Hebei Province, and surrounding areas. The results suggested that short-term exposure to O 3 was significantly associated with the increased risk of mortality and that the association was positively modified by relative higher (>75th 24 h-average temperature) or extreme cold temperature (<10th 24 h-average temperature) ( 7 ).

In summary, the above studies employed different epidemiological designs to assess the impact of short-term air pollution exposure on multidimensionally adverse health outcomes. These provocative findings warrant a multiomics approach to comprehensively explore the etiological evidence, the underlying mechanisms, and the causal linkages between air pollution and health effects in China, relying on the available list of biomarkers associated with key toxic components of air pollutants. In view of the compound characteristics of air pollution complex in China, establishing innovative technologies and methods for health risk assessments of multiple exposures simultaneously as well as illustrating their joint effects and mechanisms are highly needed. In addition, the development of early warning techniques for health risks may promote residents to efficiently take actions and protections against air pollution exposures and their health hazards.

Xiaoming Shi, MD, PhD Professor and Director, National Institute of Environmental Health (NIEH), China CDC Principal Investigator, National Key Research and Development Program of China, “China Short-term Health Effects of Air Pollution Study (No.2016YFC0206500)”

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Combating air pollution in China: Why secondary pollutants are now a primary concern

by Chinese Academy of Sciences

Like most countries, China has had its problems with air pollution. However, over the last decade, a series of successful measures implemented by the Chinese government have resulted in an impressive improvement in air quality.

Nonetheless, despite this improvement, severe air pollution events still occur, and scientists already know that contributions from secondary air pollutants (pollutants formed in the lower atmosphere by chemical reactions ), such as ozone and secondary organic aerosol (SOA), have notably increased.

Yet, an understanding of how secondary air pollutants form and how they vary in response to changes in the weather and emissions of their precursor substances (i.e., primary air pollutants), remains limited. This is a key knowledge gap to address, particularly in areas with dense populations, such as the North China Plain (NCP) region, because being able to prevent or mitigate air pollution has a direct positive impact on human health and other aspects of our everyday lives, such as traffic safety.

Motivated by these aspects, a cross-institutional team of scientists in China recently designed and carried out a study to deepen our understanding of the response of secondary air pollutants to variations in meteorology and primary anthropogenic emissions. Their focus was on the warm season (May to September) in the NCP region from 2018 to 2022, chosen to reflect a phase of new measures brought in by the Chinese government at the beginning of this period.

The team employed a widely used and highly regarded model called CMAQ (Community Multiscale Air Quality Model) to estimate the changes in concentrations of secondary pollutants in response to variations in meteorological conditions and primary emissions. The findings have recently been published in Atmospheric and Oceanic Science Letters .

"Crucially, we found that, among the secondary air pollutants we modeled, reduced primary emissions contributed a staggering 96% to the decrease in fine particles , while the fluctuations in ozone levels were mainly caused by changes in meteorological conditions," explains Prof. Hongliang Zhang, one of the corresponding authors of the study.

There were also clear findings regarding other secondary pollutants. For instance, reductions in sulfate and ammonium could largely be attributed to falls in emissions, while reductions in nitrate were more sensitive to changes in the weather. The contributions of meteorological and emission changes to the overall reduction in SOA were found to be similar, in which the response of anthropogenic SOA to emission reductions was more obvious, while the change in biogenic SOA was more influenced by meteorological conditions .

Although the study highlights evident roles played by the weather with respect to certain secondary air pollutants, the take-home message, says Prof. Zhang, is "the clear importance of controlling anthropogenic emissions to mitigate secondary pollution in the NCP region during summer."

The work, however, does not stop here. Although, as mentioned, CMAQ is a well-established model, there are always methodological developments that can be made to improve the robustness and confidence in results. For instance, there are some exciting new technologies for identifying pollution sources that could be integrated, and innovative meteorological and chemical mechanisms ready to be introduced.

"Ultimately," concludes Prof. Zhang, "we want to quantify the impacts of emissions and meteorology on secondary pollutants even more accurately, so as to achieve evermore precise formulations of collaborative control strategies for mitigating concentrations of what we know in the field to be the two most critical secondary air pollutants—fine particulates and ozone."

Provided by Chinese Academy of Sciences

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Improving urban air quality in China: Beijing case study

Affiliation.

• 1 Department of Environmental Science and Engineering, Tsinghua University, Beijing, China.
• PMID: 16259425
• DOI: 10.1080/10473289.2005.10464726

China is undergoing rapid urbanization because of unprecedented economic growth. As a result, many cities suffer from air pollution. Two-thirds of China's cities have not attained the ambient air quality standards applicable to urban residential areas (Grade II). Particulate matter (PM), rather than sulfur dioxide (SO2), is the major pollutant reflecting the shift from coal burning to mixed source pollution. In 2002, 63.2 and 22.4% of the monitored cities have PM and SO2 concentrations exceeding the Grade II standard, respectively. Nitrogen oxides (NOx) concentration kept a relatively stable level near the Grade II standard in the last decade and had an increasing potential in recent years because of the rapid motorization. In general, the air pollutants emission did not increase as quickly as the economic growth and energy consumption, and air quality in Chinese cities has improved to some extent. Beijing, a typical representative of rapidly developing cities, is an example to illustrate the possible options for urban air pollution control. Beijing's case provides hope that the challenges associated with improving air quality can be met during a period of explosive development and motorization.

Publication types

• Research Support, Non-U.S. Gov't
• Air Pollutants / analysis*
• Air Pollutants / standards
• Air Pollution / analysis
• Air Pollution / prevention & control*
• Nitrogen Oxides / analysis*
• Nitrogen Oxides / standards
• Particle Size
• Particulate Matter
• Population Density
• Power Plants
• Sulfur Dioxide / analysis*
• Sulfur Dioxide / standards
• Urbanization
• Vehicle Emissions
• Air Pollutants
• Nitrogen Oxides
• Sulfur Dioxide

Potential and health impact assessment of air pollutant emission reduction: a case study of China

• Original Paper
• Published: 23 May 2024

Cite this article

• Yuanying Chi 1 ,
• Yangyi Zhang 1 ,
• Xufeng Zhang 1 &
• Baoliu Liu 1 , 2  

Explore all metrics

Air pollution has become the world’s largest human health and environmental risk factor. This study used the greenhouse gas and air pollution interactions and synergies model to analyze the emissions, emission reduction potential, and health impacts of atmospheric pollutants (SO 2 , NO x , and PM2.5) in 31 regions of China (excluding Hong Kong, Macau, and Taiwan). Meanwhile, the spatial aggregation of atmospheric pollutants was studied by combining the spatial autocorrelation Moran index. Research results indicate that under the background of implementing pollution control policies and advancing emission reduction technologies, the emissions of SO 2 and NO x are expected to significantly decrease by 2030, demonstrating significant potential for emission reduction. Moreover, some regions in East China, such as Zhejiang, Shandong, and Jiangsu, with significant emission reduction and potential, exhibit relatively high GDP and power generation. This finding also includes regions with abundant and intensive energy reserves such as Shanxi. In addition, significant agglomeration effects and spatial regional differences in atmospheric pollutant emissions are observed. The results of spatial autocorrelation analysis show that by 2030, the spatial clustering level of SO 2 emissions will be strengthened, whereas that of NO x emissions will be reduced. Furthermore, in terms of health impacts, a significant reduction in PM2.5 emissions and attributable deaths is forecasted by 2030. Among them, Guangdong Province has the highest reduction in PM2.5 attributable deaths, reaching 48,332 people, whereas Hainan Province has the highest reduction rate in PM2.5 attributable deaths, reaching 92%. Therefore, we should formulate reasonable emission reduction measures to promote high-quality economic and social development in the region.

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This is a part research accomplishment of the National Natural Science Foundation of China Key Project “Research on the Construction of China’s Economic Transformation Model for Carbon Neutrality” (72140001).

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School of Economics and Management, Beijing University of Technology, Beijing, 100124, China

Yuanying Chi, Yangyi Zhang, Xufeng Zhang & Baoliu Liu

Institute of Eco-Civilization Studies, Beijing University of Technology, Beijing, 100124, China

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Yuanying Chi and Yangyi Zhang wrote the main manuscript text and Xufeng Zhang, Baoliu Liu prepared receipt revisions. All authors reviewed the manuscript.

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Chi, Y., Zhang, Y., Zhang, X. et al. Potential and health impact assessment of air pollutant emission reduction: a case study of China. Clean Techn Environ Policy (2024). https://doi.org/10.1007/s10098-024-02880-5

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Published : 23 May 2024

DOI : https://doi.org/10.1007/s10098-024-02880-5

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Case Study – Air Pollution in China

Beijing and other large urban centers in China suffer from regular problems with high pollution levels.

In Beijing, high pollution levels have been recorded on several occasions in recent months without an alert being issued. The high levels of air pollution in major urban and industrialized areas in China may aggravate bronchial, sinus or asthma conditions.

Travelers should adhere to advice from local authorities on health-related matters. Be aware that pollution levels may be considerable, even though there is no alert in place. If travelers are concerned, and want to receive alerts for air pollution level, SAFEY sends users notifications in-app.

SAFEY began sending out pollution level alerts after authorities issued a yellow alert between February 20th-23rd, in 2014. SAFEY sends regular alerts for changes to air quality in China.

Advice given to travelers:

• Restrict outdoor activities, if you must go out, try to limit the amount of time you are out to strictly essential activities.
• People with respiratory or cardiac disorders should take their medication, and minimize strenuous outdoor activity on smog alert days.
• Minimize your use of items that increase pollution, such as cars, gas powered lawn mowers and other vehicles.
• Avoid driving due to low visibility.
• Do not burn debris or other items during an air quality alert
• If an alternative source of heating is available, don’t use solid fuel heaters.

It is also important to make sure that:

• Vehicles are well maintained.
• Wood heaters are used correctly.

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