Making measurable progress in improving China's air and health
Authors: Daniel Greenbaum
Journal: The Lancet Planetary Health (2018)

Ambient air pollution emanates from a dizzying array of combustion sources—eg, the burning of fuel for transportation, electricity, industry, agricultural burning, and home heating and cooking—and non-combustion sources, including construction and other dusts, off-gassing from agricultural practice, wastewater treatment, and many others. Populations across the globe are exposed to this complex mixture, and the latest health science estimates that it contributed to approximately 4·1 million deaths from heart disease, stroke, lung cancer, and chronic lung disease in 2016.1Gakidou E Afshin A Abajobir AA et al.Global, regional, and national comparative risk assessment of 84 behavioural, environmental and occupational, and metabolic risks or clusters of risks, 1990–2016: a systematic analysis for the Global Burden of Disease Study 2016.Lancet. 2017; 390: 1345-1422Summary Full Text Full Text PDF PubMed Scopus (1631) Google Scholar Nowhere is this public health impact more keenly felt than in two rapidly developing countries, China and India, which together account for more than half of the public health burden.2Health Effects InstituteState of Global Air 2018. Special report.http://www.stateofglobalair.org/sites/default/files/soga-2018-report.pdfDate: 2018Date accessed: June 13, 2018Google Scholar Reducing population exposure from these sources of air pollution is a huge technical, economic, and often political challenge. Yet we have seen substantial progress over the past half century in the UK, the USA, and elsewhere, with investments in air pollution science, strong government action, and development of new and efficient technologies for pollution control.3National Research CouncilAir quality management in the United States. National Academies Press, Washington, DC2004Google Scholar For example, as a result of vehicle emission controls, levels of ambient carbon monoxide in the Los Angeles (CA, USA) area have fallen from more than 40 ppm in the 1960s to under 8 ppm (the current national standard), even while the number of vehicles have doubled, and vehicle miles travelled have tripled.4National Research CouncilManaging carbon monoxide pollution in meteorological and topographical problem areas. National Academies Press, Washington, DC2003Google Scholar Furthermore, increasing evidence shows that these reductions have translated into health improvements: for example, a substantial improvement in lung function growth was seen in children growing up in a cohort in Southern California in 2003 compared with children in similar cohorts who grew up there in 1992–96, when air was more highly polluted.5Gilliland F Avol E McConnell R et al.The effects of policy-driven air quality improvements on children's respiratory health.https://www.healtheffects.org/system/files/GillilandRR190.pdfDate: January, 2017Date accessed: June 12, 2018Google Scholar In the wake of increased awareness of air pollution and its health implications for China, the Chinese Government has responded with substantial investments in atmospheric science to better understand the sources and causes of the air pollution, and with a multidimensional control strategy aimed at reducing emissions from vehicle and fuels, coal-fired electric generating units, and many other sources. In The Lancet Planetary Health, Jing Huang and colleagues6Huang J Pan X Guo X Li G Health impact of China's Air Pollution Prevention and Control Action Plan: an analysis of national air quality monitoring and mortality data.Lancet Planet Health. 2018; 2: e313-e323Summary Full Text Full Text PDF PubMed Scopus (324) Google Scholar have now contributed a systematic analysis of how these many actions have measurably reduced air pollution in 74 key Chinese cities that have the longest track record of measuring air pollution. The authors found that annual average concentrations of PM2·5 decreased by 33·3% (95% CI 16·3–50·3), PM10 by 27·8% (8·0–47·5), sulphur dioxide by 54·1% (28·2–80·0), and carbon monoxide by 28·2% (3·1–53·3) in the 74 key cities. The investigators went further to apply the latest—and widely recognised—integrated exposure–response functions7Cohen AJ Brauer M Burnett R et al.Estimates and 25-year trends of the global burden of disease attributable to ambient air pollution: an analysis of data from the Global Burden of Diseases Study 2015.Lancet. 2017; 389: 1907-1918Summary Full Text Full Text PDF PubMed Scopus (3222) Google Scholar to estimate that in 2017 there were 47 240 (95% CI 25 870–69 990) fewer deaths and 710 020 (420 230–1 025 460) fewer years of life lost attributable to air pollution in the 74 key cities than in 2013, a substantial public health improvement. Having documented this progress, the investigators are also careful to note the challenges in undertaking such an analysis—and in making continuing air quality progress in China. First, although they did analyses to test whether meteorology rather than air quality control might be responsible for the improvement, and did not find evidence that this was the case, they note that weather might still have contributed. Although 5 years is a reasonable initial time to test air quality trends, the multiple atmospheric and meteorological variables argue for continued surveillance to ensure that progress is real and lasting. Second, they note that economic trends other than the air pollution control measures (ie, improvements in the efficiency of industries) might have also contributed, reminding us of the importance of tracking many factors that could improve air quality and public health over the long term, including the economy and changes in health care (eg, improvements in cardiovascular treatment care that extend life). They do, however, present strong evidence of reduced emissions from key sources that could only have resulted from the implementation of the required control measures, suggesting an important role for the Government's actions in achieving progress. Third, the investigators note that even with the improvements in air quality, levels still substantially exceed China's air quality standards for fine particulate matter (PM2·5), and about 365 000 premature deaths could still be attributed to PM2·5 air pollution, even accounting for the 47 240 fewer deaths reported. This finding should not come as a surprise: every country has accomplished cleaner air only after many years of effort (close to 50 years in the USA, for example), and after continued revisiting and improvement of control measures. To this end, it is heartening to see the Chinese Government, even as it notes the progress it has made, make a new set of commitments to an additional 3 years of action.8Leng S China has new three-year plan to clean up environment, minister says. South China Morning Post.http://www.scmp.com/news/china/policies-politics/article/2137666/china-has-new-three-year-plan-clean-environmentDate: March 18, 2018Date accessed: June 12, 2018Google Scholar Fourth, the investigators report that even as progress has been made on reducing PM2·5 pollution, there has been substantial growth in exposures to, and health effects from, ozone air pollution. This trend is important to note and will require further attention. Although many of the sources of the pollutants that contribute to the formation of ozone smog are similar to those needing control for PM2·5 , the complex chemistry in which these chemicals mix with ultraviolet radiation and weather to form ozone makes successful control of ozone levels considerably more challenging, a fact that has made continued progress on ozone in countries with stronger air quality management and controls such as the USA very difficult. Clearly, the issues surrounding air pollution in China pose public health challenges. The actions of the Chinese Government—and this new analysis by Huang and colleagues documenting the substantial progress—augur very well for continued learning and improvement in tackling this important issue. I declare no competing interests. Health impact of China's Air Pollution Prevention and Control Action Plan: an analysis of national air quality monitoring and mortality dataSubstantial reductions in mortality and YLL related to control of ambient air pollution were achieved from 2013 to 2017 in China, indicating appreciable effectiveness of China's APPCAP. However, emissions control efforts for ozone and nitrogen dioxide should be strengthened in the future. Full-Text PDF Open Access