Air pollution health burden embodied in China's supply chains

Product trade plays an increasing role in relocating production and the associated air pollution impact among sectors and regions.While a comprehensive depiction of atmospheric pollution redistribution through trade chains is missing,which may hinder targeted clean air cooperation among sectors and regions.Here,we combined five state-of-the-art models from physics,economy,and epidemiology to track the anthropogenic fine particle matters(PM_(2.5))related premature mortality along the supply chains within China in 2017.Our results highlight the key sectors that affect PM_(2.5)-related mortality from both production and consumption perspectives.The consumption-based effects from food,light industry,equipment,construction,and services sectors,caused 2e22 times higher deaths than those from a production perspective and totally contributed 63%of the national total.From a cross-boundary perspective,25.7%of China's PM_(2.5)-related deaths were caused by interprovincial trade,with the largest transfer occurring from the central and northern regions to well-developed east coast provinces.Capital investment dominated the cross-boundary effect(56%of the total)by involving substantial equipment and construction products,which greatly rely on product exports from regions with specific resources.This supply chain-based analysis provides a comprehensive quantification and may inform more effective joint-control efforts among associated regions and sectors from a health risk perspective.

Synergetic roadmap of carbon neutrality and clean air for China

It is well recognized that carbon dioxide and air pollutants share similar emission sources so that synergetic policies on climate change mitigation and air pollution control can lead to remarkable co-benefits on greenhouse gas reduction,air quality improvement,and improved health.In the context of carbon peak,carbon neutrality,and clean air policies,this perspective tracks and analyzes the process of the synergetic governance of air pollution and climate change in China by developing and monitoring 18 indicators.The 18 indicators cover the following five aspects:air pollution and associated weather-climate conditions,progress in structural transition,sources,inks,and mitigation pathway of atmospheric composition,health impacts and benefits of coordinated control,and synergetic governance system and practices.By tracking the progress in each indicator,this perspective presents the major accomplishment of coordinated control,identifies the emerging challenges toward the synergetic governance,and provides policy recommendations for designing a synergetic roadmap of Carbon Neutrality and Clean Air for China.

Rapid improvement of PM2.5 pollution and associated health benefits in China during 2013–2017

Exposure to fine particulate matter(PM2.5)is known to harm public health.In China,after implementation of aggressive emissions control measures under the Action Plan of Air Pollution Prevention and Control(2013-2017),air quality has significantly improved.In this work,we investigated changes in PM2.5 exposure and the associated health impacts in China for the period 2013-2017.We used an optimal estimator of PM2.5 combining in-situ observations,satellite measurements,and simulations from a chemical transport model to derive the spatial and temporal variations in PM2.5 exposure,and then used welldeveloped exposure-response functions to estimate the premature deaths attributable to PM2.5 exposure.We found that national population-weighed annual mean PM2.5 concentrations decreased from 67.4μgm-3 in 2013 to 45.5μgm-3 in 2017(32%reduction).This rapid decrease in PM2.5 pollution led to a 14%reduction in premature deaths due to long-term exposure.We estimated that,during 2013-2017,the premature deaths attributable to long-term PM2.5 exposure decreased from 1.2 million(95%CI:1.0,1.3;fraction of total mortality:13%)in 2013 to 1.0 million(95%CI:0.9,1.2;10%)in 2017.Despite the rapid decrease in annual mean PM2.5 concentrations,health benefits associated with reduced long-term exposure were limited,because for many cities,the PM2.5 levels remain at the portion where the exposure-response function is less steeper than that at the lowconcentration end.We also found that the deaths associated with acute exposure decreased by 61%during 2013-2017 due to rapid reduction in the number of heavily polluted days.Our results confirm that clean air policies in China have mitigated the air pollution crisis;however,continuous emissions reduction efforts are required to protect citizens from air pollution.

Impact of China’s Air Pollution Prevention and Control Action Plan on PM2.5 chemical composition over eastern China

China promulgated the Air Pollution Prevention and Control Action Plan(the Action Plan)in 2013 and developed stringent control measures to mitigate fine particulate matter(PM2.5) pollution.Here,we investigated the PM2.5 chemical composition changes over eastern China associated with the Action Plan during 2013-2017 using satellite-based PM2.5 chemical composition data derived using CMAQ simulations and satellite inputs.The PM2.5 concentrations decreased considerably during this time as a result of the reductions in all chemical species in PM2.5.The population-weighted mean concentrations over eastern China decreased from 11.1 to 6.7μgm-3 for SO42-,13.8-13.1μgm-3 for NO3-,7.4-5.8μgm-3 for NH4+,9.9-8.4μgm-3 for OM,4.6-3.8μg m-3 for BC and 12.9-9.6μg m-3 for other species in PM2.5.SO42-had the largest reduction of 40%,while NO3-had the lowest reduction of 5%,resulting in a greater fraction of NO3-and a smaller fraction of SO42-in PM2.5.Among the three key regions,Beijing-Tianjin-Hebei had the largest reduction in PM2.5 and its chemical compositions.The decrease in SO42-concentrations was in line with the reduction of SO2 emissions,and the major driver of the SO2 emission reductions was the industrial sector.The decrease in NO3 concentrations was limited because the decrease in SO2 emissions and the stable NH3 emissions facilitated the formation of NO3-from HNO3,which partially offset the reduction in NOx emissions driven by the power sector.To mitigate PM2.5 pollution more effectively,future efforts are needed to reduce NH3 emissions.

Attribution of PM_(2.5) exposure in Beijing-Tianjin-Hebei region to emissions:implication to control strategies

The Beijing-Tianjin-Hebei(BTH) region is one of the most heavily polluted regions in China,with both high PM_(2.5) concentrations and a high population density.A quantitative source-receptor relationship can provide valuable insights that can inform effective emission control strategies.Both source apportionment(SA) and source sensitivity(SS) can provide such information from different perspectives.In this study,both methods are applied in northern China to identify the most significant emission categories and source regions for PM_(2.5) exposure in BTH in 2013.Despite their differences,both models show similar distribution patterns for population and simulated PM_(2.5) concentrations,resulting in overall high PM_(2.5) exposure values(approximately 110 μg/m~) and particularly high exposure values during the winter(approximately 200 μ/m~).Both methods show that local emissions play a dominant role(70%),with some contribution from surrounding provinces(e.g.,Shandong) via regional transport.The two methods also agree on the priority of local emission controls:both identify industrial,residential,and agricultural emissions as the top three categories that should be controlled locally.In addition,the effect of controlling agricultural ammonia emissions is approximately doubled when the co-benefits of reducing nitrate are considered.The synthesis of SA and SS for addressing specific categories of emissions provides a quantitative basis for the development of emission control strategies and policies for controlling PM_(2.5)in China.

Impacts of meteorology and emission variations on the heavy air pollution episode in North China around the 2020 Spring Festival

Based on the Weather Research and Forecasting model and the Models-3 community multi-scale air quality model(WRF-CMAQ),this study analyzes the impacts of meteorological conditions and changes in air pollutant emissions on the heavy air pollution episode occurred over North China around the 2020 Spring Festival(January to Februray 2020).Regional reductions in air pollutant emissions required to eliminate the PM2.5 heavy pollution episode are also quantified.Our results found that meteorological conditions for the Beijing-Tianjin-Hebei and surrounding"2+26"cities are the worst during the heavy pollution episode around the 2020 Spring Festival as compared with two other typical heavy pollution episodes that occurred after 2015.However,because of the substantial reductions in air pollutant emissions in the"2+26"cities in recent years,and the32%extra reduction in emissions during January to February 2020 compared with the baseline emission levels of the autumn and winter of 2019 to 2020,the maximum PM2.5 level during this heavy pollution episode around the 2020 Spring Festival was much lower than that in the other two typical episodes.Yet,these emission reductions are still not enough to eliminate regional heavy pollution episodes.Compared with the actual emission levels during January to February 2020,a 20%extra reduction in air pollutant emissions in the"2+26"cities(or a 45%extra reduction compared with baseline emission levels of the autumn and winter of 2019 to 2020)could help to generally eliminate regionwide severe pollution episodes,and avoid heavy pollution episodes that last three or more consecutive days in Beijing;a 40%extra reduction in emissions(or a 60%extra reduction compared with baseline emission levels of the autumn and winter of 2019 to 2020)could help to generally eliminate regionwide and continuous heavy pollution episodes.Our analysis finds that during the clean period after the heavy pollution episode around the 2020 Spring Festival,the regionwide heavy pollution episode would only occur with at least a 10-fold increase in air pollutant emissions.

Increasing life expectancy in China by achieving its 2025 air quality target

China is striving to build a“Beautiful China”characterized by clean air.The country has committed to further reducing its national mean fine particle(PM_(2.5))concentration by 10%from 2020 to 2025,following the substantial improvements in its air quality during the past decade.Meanwhile,the“Healthy China”mission has pledged to increase the national mean life expectancy by one year during the same period.Yet,to what extent will the“Beautiful China”mission contribute to the“Healthy China”vision by reducing the levels of the detrimental PM_(2.5) is still unclear.Here,by coupling the life table approach and an epidemiological concentration-response model,this study quantifies the potential benefits of achieving China's 2025 air quality target on the national life expectancy.The analysis reveals that the Chinese citizen could expect to extend the average life expectancy by 42.5 days by 2025 due to improved air quality.In addition,if the Chinese government outperforms the planned air quality target,as it usually does,the gains would increase to 65.4 days,~18% of the“Healthy China”life expectancy increment task.Further reductions in PM_(2.5) concentration would lead to accelerated gains in life expectancy both nationally and at the city level,providing strong incentives for the authorities to keep improving air quality.This study reveals the notable benefits on individual life that could be expected from air quality improvement in China and suggests that longer life expectancy is achievable by implementing a health-prioritized air quality management mechanism.

Association of PM_(2.5)Reduction with Improved Kidney Function:A Nationwide Quasiexperiment among Chinese Adults

Background.Increasing evidence from human studies has revealed the adverse impact of ambient fine particles(PM_(2.5))on health outcomes related to metabolic disorders and distant organs.Whether exposure to ambient PM_(2.5)leads to kidney impairment remains unclear.The rapid air quality improvement driven by the clean air actions in China since 2013 provides an opportunity for a quasiexperiment to investigate the beneficial effect of PM_(2.5)reduction on kidney function.Methods.Based on two repeated nationwide surveys of the same population of 5115 adults in 2011 and 2015,we conducted a difference-indifference study.Variations in long-term exposure to ambient PM_(2.5)were associated with changes in kidney function biomarkers,including estimated glomerular filtration rate by serum creatinine(GFRscr)or cystatin C(GFRcys),blood urea nitrogen(BUN),and uric acid(UA).Results.For a 10μg/m^(3)reduction in PM_(2.5),a significant improvement was observed for multiple kidney functional biomarkers,including GFRscr,BUN and UA,with a change of 0.42(95%confidence interval[CI]:0.06,0.78)mL/min/1.73m^(2),-0.38(-0.64,-0.12)mg/dL,and-0.06(-0.12,-0.00)mg/dL,respectively.A lower socioeconomic status,indicated by rural residence or low educational level,enhanced the adverse effect of PM_(2.5)on kidney function.Conclusions.These results support a significant nephrotoxicity of PM_(2.5)based on multiple serum biomarkers and indicate a beneficial effect of improved air quality on kidney function.