2000年—2018年中国和印度的长期PM2.5污染暴露的疾病负担研究
Disease burden assessment exposure to long-term PM2.5 pollution in China and India (2000—2018)
- 2023年27卷第8期 页码:1834-1843
纸质出版日期: 2023-08-07
DOI: 10.11834/jrs.20231758
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纸质出版日期: 2023-08-07
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PM2.5作为空气污染物,对人体健康构成了潜在威胁。中国和印度是全球人口最多的两个发展中国家,PM2.5污染造成的疾病负担问题尤为严重。因此,本文基于长时间序列高分辨率(0.01°×0.01°)卫星反演的PM2.5浓度数据,分析了中国和印度19年(2000年—2018年)的PM2.5时空格局变化和人口暴露情况;基于综合暴露响应模型全面评估了两个国家因PM2.5长期暴露导致的6种疾病(急性下呼吸道感染、慢性阻塞性肺病、二型糖尿病、缺血性心脏病、肺癌和中风)的过早死亡人数。结果表明,中国PM2.5浓度的高值区集中在新疆、四川盆地、华北平原以及长江经济带等地区,年人口加权浓度总体呈减少趋势(2000年为50 μg∙m-3,2018年为40.8 μg∙m-3);印度PM2.5浓度的高值区集中在北部地区,年人口加权浓度一直呈上升趋势(2000年为51.5 μg∙m-3,2018年为76.4 μg∙m-3)。对于中国而言,PM2.5暴露造成的过早死亡人数从2000年的90.8万人增长至2018年的137.8万人,增长了47万人;中风是导致过早死亡的主要疾病终端,占总死亡人数的45.9%(56.3万人)。印度PM2.5暴露造成的过早死亡人数从2000年的34.3万人增长至2018年的75万人,增长了40.7万人;缺血性心脏病和中风是导致过早死亡的主要疾病终端,分别占比39.9%(20.2万人)和25.5%(12.9万人)。研究结果有望为决策者和污染控制机构提供参考,有助于制定空气污染治理政策。
With the increasing frequency of air pollution incidents worldwide, many studies have focused on the disease burden from long-term exposure to PM2.5 pollution. In China and India, the two most populous developing countries in the world, the disease burden attributable to PM2.5 exposure are particularly serious. Therefore, these countries need to develop a multi-year and comprehensive dataset of PM2.5-related premature deaths to support their future air pollution prevention policies. However, only few studies have explored this topic over the past years. To fill this gap, this study analyzed the spatial and temporal patterns of PM2.5 concentrations and changes of population exposure to PM2.5 in China and India over the past 19 years (2000—2018) using high-resolution (0.01°×0.01°) satellite data. Combined with the Integrated Exposure Response (IER) model, this study comprehensively assessed the premature deaths from six diseases due to long-term PM2.5 exposure, including acute lower respiratory infection, (ALRI), Chronic Obstructive Pulmonary Disease, (COPD), type 2 diabetes (DIA), Ischemic Heart Disease (IHD), lung cancer (LNC), and stroke (STR).
Results show that those areas with high levels of PM2.5 concentrations in China were concentrated in Xinjiang, Sichuan Basin, North China Plain, and the Yangtze River Economic Belt. The annual population-weighted PM2.5 concentrations showed a decreasing trend (50 μg∙m-3 in 2000 and 40.8 μg∙m-3 in 2018). In India, high levels of PM2.5 concentrations were concentrated in the north, including Punjab, Haryana, and Uttar Pradesh. The annual population-weighted PM2.5 concentrations increased from 51.5 μg∙m-3 in 2000 to 76.4 μg∙m-3 in 2018. The number of premature deaths caused by PM2.5 exposure in China increased by 34.1% from 908000 in 2000 to 1378000 in 2018, with the annual average premature deaths totaling 1228000. STR was the major contributor to total premature deaths in the country, accounting for 45.9% (563000) of all fatalities. In India, the number of premature deaths attributable to PM2.5 increased rapidly from 343000 in 2000 to 750000 in 2018, with a net increase of 407000. The annual average premature deaths were 506000, the majority of which were attributed to IHD and STR, which accounted for 39.9% (202000) and 25.5% (129000) of all deaths, respectively. Moreover, DIA was responsible for 29000 (2.3%) and 30000 (6%) premature deaths in China and India, respectively, and therefore should not be ignored.
Overall, this study established a long-term series of high-resolution datasets on premature deaths due to PM2.5 exposure in China and India. The number of premature deaths caused by air pollution remain high in China and India, both of which have high PM2.5 concentrations and population density, thus necessitating stricter air pollution control policies. These results provide a reference for the formulation of air pollution policies in these countries. However, in estimating premature deaths due to PM2.5, the baseline mortality rate did not consider the differences caused by the level of development and medical treatment within a country. Therefore, in a future study, the researchers will incorporate the sub-national baseline mortality rate when assessing premature deaths.
随着世界经济的快速发展和城市化进程的加快,PM2.5污染已经成为一个全球性的环境和公共健康问题。PM2.5指的是空气动力学直径小于2.5 μm的颗粒物,又称可吸入肺颗粒物。它体积小,表面积大,能在空气中长期停留,并远距离传输,携带的有毒物质,能够随着呼吸深入人体肺部(
IQAir发布的《2019年世界空气质量报告》显示,2019年,印度和中国是世界排名第5和11位PM2.5污染严重的国家。此外,全球PM2.5污染较严重的前30位城市有21个位于印度;有1个位于中国(https://www.iqair.com/world-air-quality-report[2022-01-05])。可以看出,中国和印度的PM2.5污染问题十分严峻。美国健康效应研究所HEI(Health Effects Institute)发布的《2020年全球空气状况特别报告》指出,2019年,PM2.5长期暴露导致了全球414万人过早死亡,占全球总死亡人数的7%,是危害全球公众健康的第六大因素。而其中,仅中国和印度这两个国家,PM2.5长期暴露便导致了142万和98万人过早死亡,占全球总死亡人数的58%(Health Effects Institute等,2020)。由此可见,中国和印度PM2.5污染造成的过早死亡疾病负担尤为严重。
目前,已有多名学者对中国PM2.5疾病负担进行了研究(
上述研究仅仅是对单个年份或间隔年份的PM2.5浓度和过早死亡人数进行分析,而对这两个国家PM2.5浓度及疾病负担的长期的时间趋势和空间格局变化仍不清楚。此外,以往的研究大多考虑ALRI、COPD、IHD、LNC和STR这5种疾病终端,没有考虑DIA引起的过早死亡人数,这造成了PM2.5暴露疾病负担评估的不全面(
本研究使用的主要数据源(
数据集 | 时间/年份 | 空间分辨率 | 数据来源 |
---|---|---|---|
PM2.5浓度 | 2000—2018 | 0.01° | Hammer和Van Donkelaar团队(https://sites.wustl.edu/acag/datasets/surface-pm2-5/) |
人口 | 2000—2018 | 0.0083° | LandScanTM(https://landscan.ornl.gov/) |
年龄结构 | 2000—2018 | — | IHME(http://ghdx.healthdata.org/record/ihme-data/gbd-2019-population-estimates-1950—2019) |
基准死亡率 | 2000—2018 | — | GBD(http://ghdx.healthdata.org/gbd-results-tool) |
本研究采用了2019年IER模型来定量评估长期暴露在PM2.5环境中造成的过早死亡人数。该模型于2010年GBD首次提出(
RR(Cg)={1, Cg<C01+α(1-e-β(Cg-C0)δ),Cg≥C0} | (1) |
式中,Cg表示网格g的PM2.5真实浓度值;C0为PM2.5理论阈值,这里参考2019年GBD公布的最新结果(5 μg∙m-3)。当环境PM2.5浓度低于该阈值浓度时,RR值为1,即PM2.5暴露不会对人体造成危害。当环境PM2.5浓度高于该阈值浓度时,RR值大于1,即PM2.5暴露会对人体造成危害。α、β和δ是描述6种疾病终端的综合暴露响应曲线形状参数。这里将RR的平均值用于计算过早死亡人数,如下式所示:
PAFg, a, i=RRg, a, i-1RRg, a, i | (2) |
Mg, a, i=POPg, a, i×BMRi×PAFg, a, i | (3) |
式中,PAFg,a,i为网格g内年龄组a疾病终端i的归因系数;RRg,a,i为网格g内年龄组a疾病终端i的相对危险度;Mg,a,i为网格g内年龄组a疾病终端i的过早死亡人数;POPg,a为网格g内年龄组a的人口数量;年龄组a包含0—5岁、25—30岁、30—35岁、35—40岁、40—45岁、…、90—95岁和>95岁在内的16组;BMRi为疾病终端i国家层面基准死亡率。
中国和印度PM2.5浓度19年年均分布具有明显的空间格局(
图1 中国和印度2000年—2018年PM2.5浓度年均空间分布
Fig. 1 Average spatial distribution of PM2.5 concentrations in China and India over 2000—2018
(审图号:GS京(2023)0738号)
图2 中国和印度2000年—2018年和2013年—2018年PM2.5浓度变化的空间分布
Fig. 2 Spatial distributions of change rates in PM2.5 concentrations during 2000—2018 and 2013—2018 in China and India
(审图号:GS京(2023)0738号)
中国和印度的年均人口加权PM2.5浓度随时间变化趋势如
图3 2000年—2018年中国和印度暴露于不同浓度PM2.5的人口比例分布及PM2.5年均人口加权浓度年际变化
Fig. 3 Proportion of the population exposed to different PM2.5 concentrations and the inter-annual variation of population-weighted PM2.5 concentrations over China and India during 2000—2018
2000年—2018年,中国和印度因PM2.5长期暴露导致的过早死亡人数空间分布如
图4 2000年—2018年中国和印度总过早死亡人数分布(ALRI、COPD、DIA、IHD、LNC和STR)
Fig. 4 Distribution of total premature deaths (ALRI, COPD, DIA, IHD, LNC, and STR) in China and India (2000—2018)
审图号:GS京(2023)0738号
2000年—2018年,中国和印度因PM2.5暴露造成的总过早死亡人数(ALRI、COPD、DIA、IHD、LNC和STR)时间变化见
图5 2000年—2018年中国和印度总过早死亡(ALRI、COPD、DIA、IHD、LNC和STR)年际变化
Fig. 5 Interannual changes in total premature deaths (ALRI, COPD, DIA, IHD, LNC, and STR) in China and India from 2000 to 2018
不同疾病造成的过早死亡人数占总死亡人数的比例在两个国家也是有差异的(
图6 中国和印度6种疾病过早死亡人数年均值和比例
Fig. 6 Annual average number and proportion of premature deaths from six diseases in China and India
本研究结合IER模型评估了2000年—2018年中国和印度PM2.5暴露导致的过早死亡人数。本研究的结果与其他学者的研究结果与所用数据及参数对比如
图7 因PM2.5暴露导致过早死亡人数的研究结果对比
Fig. 7 Comparison of results on the number of premature deaths caused by PM2.5 exposure
文献 | 对比年份 | 地区 | PM2.5数据 | 人口数据 | 基准死亡率 | C0/(μg∙m-3) | 死亡人数/×104 |
---|---|---|---|---|---|---|---|
本研究 | 2000—2018 | 中国、印度 | 卫星反演数据集 | LandScanTM、World Bank、LandScanTM、中国统计年鉴 | GBD | 5 | 129 |
Ding等(2019) | 2013 | 中国 | 地面观测站、CMAQ模型 | GBD | — | 139 | |
Li等(2020) | 2016 | 中国 | 地面观测站、NAQPMS模型 | GPWv4 | GBD | — | 136 |
Liu等(2016) | 2013 | 中国 | 地面观测站、NAQPMS模型 | 中国统计年鉴、国家地球科学系统数据中心 | GBD | 5.8—8.8 | 137 |
Wang等(2018) | 2010 | 中国 | 卫星反演数据集 | 中国统计年鉴 | GBD | — | 127 |
Zou等(2019) | 2013 | 中国 | 地面观测站、TSAM模型 |
中国统计年鉴 资源环境科学与数据中心 | GBD、中国统计年鉴 | 5.8—8.8 | 120 |
总体上,过早死亡人数的结果存在一定不确定性和局限性。首先,所用数据集具有一定不确定性。有些地区因没有足够的地面观测站点数据来支撑验证或常受到沙尘等极端气候严重影响,PM2.5浓度遥感数据集的估算将存在误差。由于缺少更为精细的城市级基准死亡率数据,而使用国家级基准死亡率,这忽略了城市与城市之间因医疗、经济水平等不同造成的基准死亡率的差异。其次,IER模型中C0阈值的设置不一样也会有所影响,例如,
本文研究了2000年—2018年中国和印度的PM2.5浓度变化及其人口暴露情况,分析了由于PM2.5污染造成的过早死亡人数的时空分布特征和趋势。研究结果表明,2000年—2018年,中国和印度PM2.5浓度分布有明显的空间分布格局。中国PM2.5浓度高值区集中分布在新疆、四川盆地、华北平原以及长江经济带等地区;印度PM2.5高值区集中分布在北部地区。中国PM2.5人口暴露情况总体呈减缓趋势,且居住在高浓度PM2.5环境的人口比例减少;印度人口暴露情况呈加重趋势。19年来,中国和印度PM2.5过早死亡人数都呈现增加趋势以及空间不均匀分布。中国19年年均过早死亡人数达122.8万,集中在华北地区和四川盆地。印度19年年均过早死亡人数到50.6万,集中在北部地区。
总的来说,本研究针对PM2.5污染严重且人口众多的两个发展中国家,基于卫星反演的PM2.5浓度遥感数据,建立了2000年—2018年的高分辨率的PM2.5暴露导致的过早死亡人数数据集。并且,本文所选取的研究年份并不是单独一年或间隔几年,而是长时间序列的连续年份,从而分析PM2.5及其过早死亡人数的长期且连续的时空格局演变。在估算PM2.5导致的过早死亡人数时,考虑了6种疾病终端,使过早死亡人数的估算更加全面。研究结果有望为两个国家的大气污染政策的制定提供依据和参考。
但是,本文针对PM2.5导致的过早死亡人数估算中,基准死亡率的选取并未考虑国家内部发展水平、医疗水平等造成的差异,使用次国家级基准死亡率进行评估将是下一步工作的重点。
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