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Shi R, Zhang F, Shen Y, Shen J, Xu B, Kuang B, Xu Z, Jin L, Tang Q, Tian X, Wang Z. Aerosol liquid water in PM 2.5 and its roles in secondary aerosol formation at a regional site of Yangtze River Delta. J Environ Sci (China) 2024; 138:684-696. [PMID: 38135431 DOI: 10.1016/j.jes.2023.04.030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2022] [Revised: 04/22/2023] [Accepted: 04/22/2023] [Indexed: 12/24/2023]
Abstract
Aerosol liquid water content (ALWC) plays an important role in secondary aerosol formation. In this study, a whole year field campaign was conducted at Shanxi in north Zhejiang Province during 2021. ALWC estimated by ISORROPIA-II was then investigated to explore its characteristics and relationship with secondary aerosols. ALWC exhibited a highest value in spring (66.38 µg/m3), followed by winter (45.08 µg/m3), summer (41.64 µg/m3), and autumn (35.01 µg/m3), respectively. It was supposed that the secondary inorganic aerosols (SIA) were facilitated under higher ALWC conditions (RH > 80%), while the secondary organic species tended to form under lower ALWC levels. Higher RH (> 80%) promoted the NO3- formation via gas-particle partitioning, while SO42- was generated at a relative lower RH (> 50%). The ALWC was more sensitive to NO3- (R = 0.94) than SO42- (R = 0.90). Thus, the self-amplifying processes between the ALWC and SIA enhanced the particle mass growth. The sensitivity of ALWC and OX (NO2 + O3) to secondary organic carbon (SOC) varied in different seasons at Shanxi, more sensitive to aqueous-phase reactions (daytime R = 0.84; nighttime R = 0.54) than photochemical oxidation (daytime R = 0.23; nighttime R = 0.41) in wintertime with a high level of OX (daytime: 130-140 µg/m3; nighttime: 100-140 µg/m3). The self-amplifying process of ALWC and SIA and the aqueous-phase formation of SOC will enhance aerosol formation, contributing to air pollution and reduction of visibility.
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Affiliation(s)
- Ruifang Shi
- College of Environmental and Resource Sciences, Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Zhejiang University, Hangzhou 310058, China
| | - Fei Zhang
- College of Environmental and Resource Sciences, Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Zhejiang University, Hangzhou 310058, China
| | - Yemin Shen
- Zhejiang Ecological and Environmental Monitoring Center, Hangzhou 310012, China
| | - Jiasi Shen
- Zhejiang Ecological and Environmental Monitoring Center, Hangzhou 310012, China
| | - Bingye Xu
- Zhejiang Ecological and Environmental Monitoring Center, Hangzhou 310012, China
| | - Binyu Kuang
- College of Environmental and Resource Sciences, Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Zhejiang University, Hangzhou 310058, China
| | - Zhengning Xu
- College of Environmental and Resource Sciences, Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Zhejiang University, Hangzhou 310058, China
| | - Lingling Jin
- Zhejiang Ecological and Environmental Monitoring Center, Hangzhou 310012, China
| | - Qian Tang
- Zhejiang Ecological and Environmental Monitoring Center, Hangzhou 310012, China
| | - Xudong Tian
- Zhejiang Ecological and Environmental Monitoring Center, Hangzhou 310012, China
| | - Zhibin Wang
- College of Environmental and Resource Sciences, Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Zhejiang University, Hangzhou 310058, China; ZJU-Hangzhou Global Scientific and Technological Innovation Center, Zhejiang University, Hangzhou 311215, China.
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Zhang L, Wang Y, Xie W, Li W, Kojima T, Zhang D. High heterogeneity and aging state of mineral particles in a slowly-moving dust plume on the southwestern coast of Japan. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 916:170316. [PMID: 38278236 DOI: 10.1016/j.scitotenv.2024.170316] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Revised: 01/16/2024] [Accepted: 01/18/2024] [Indexed: 01/28/2024]
Abstract
Aerosol particles in two size ranges, namely 0.18-1.4 μm (fine) and larger than 1.4 μm (coarse), were collected in the pre-dust, in-dust, and post-dust air during the passage of a slowly-moving dust event at a coastal site in southwestern Japan. We identified the composition and size of individual particles using a scanning electron microscope to investigate the variations during dust passage. The particles could be classified as mineral-seasalt mixtures, non-mixture minerals, sulfur-containing minerals, and seasalt particles, and the number fractions of these type particles in the two size ranges exhibited significant variation across the three periods. In the coarse size range, mixture particles accounted for 17.6 %, 26.8 %, and 37.8 % of the particles in the pre-dust, in-dust, and post-dust air, respectively. Non-mixture particles made up 36.8 %, 29.2 %, and 24.3 % in the same respective periods. In the in-dust air, the average relative ratio of sulfur content in sulfur-containing mineral particles in the coarse range was 5.5 %, whereas in the fine range, it was 17.2 %. The aging state of sea salt components, described by the Cl loss and reflecting the changes in particles due to chemical reactions, exhibited significant differences in the two size ranges. In the fine range, the aging of >90 % particles was predominantly influenced by sulfate formation in the in-dust air. In contrast, nitrate likely played a certain role in both the pre-dust and post-dust air. In the coarse range, the aging was independent of sulfate formation. These results indicate the close dependence of the aging of dust particles on their size and the notable variations of the aged states, underscoring the essentiality to treat dust particles properly according to time and space for a better understanding on their roles in the marine atmosphere.
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Affiliation(s)
- Long Zhang
- Faculty of Environmental and Symbiotic Sciences, Prefectural University of Kumamoto, Kumamoto 862-8502, Japan
| | - Yalou Wang
- Faculty of Environmental and Symbiotic Sciences, Prefectural University of Kumamoto, Kumamoto 862-8502, Japan
| | - Wenwen Xie
- Faculty of Environmental and Symbiotic Sciences, Prefectural University of Kumamoto, Kumamoto 862-8502, Japan
| | - Wenshuai Li
- Frontier Science Center for Deep Ocean Multispheres and Earth System (FDOMES) and Physical Oceanography Laboratory, Ocean University of China, Qingdao 266100, China; College of Oceanic and Atmospheric Sciences, Ocean University of China, Qingdao 266100, China
| | - Tomoko Kojima
- Department Earth and Environmental Science, Faculty of Advanced Science and Technology, Kumamoto University, Kumamoto 860-8555, Japan
| | - Daizhou Zhang
- Faculty of Environmental and Symbiotic Sciences, Prefectural University of Kumamoto, Kumamoto 862-8502, Japan.
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Liu T, Lin Y, Chen J, Chen G, Yang C, Xu L, Li M, Fan X, Zhang F, Hong Y. Pollution mechanisms and photochemical effects of atmospheric HCHO in a coastal city of southeast China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 859:160210. [PMID: 36395845 DOI: 10.1016/j.scitotenv.2022.160210] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2022] [Revised: 11/10/2022] [Accepted: 11/12/2022] [Indexed: 06/16/2023]
Abstract
Formaldehyde (HCHO) is a vital reactive carbonyl compound, which plays an important role in the photochemical process and atmospheric oxidation capacity. However, the current studies on the quantification of HCHO impacts on atmospheric photochemistry in southeast coastal areas of China with an obvious upward trend of ozone remain scarce and unclear, thus limiting the full understanding of formation mechanism and control strategy of photochemical pollution. Here, systematic field campaigns were conducted at a typical coastal urban site with good air quality to reveal HCHO mechanism and effects on O3 pollution mechanism during spring and autumn, when photochemical pollution events still frequently appeared. Positive Matrix Factorization model results showed that secondary photochemical formation made the largest contributions to HCHO (69 %) in this study. Based on the photochemical model, the HCHO loss rates in autumn were significantly higher than those in spring (P < 0.05), indicating that strong photochemical conditions constrain high HCHO levels in certain situations. HCHO mechanism increased the ROx concentrations by 36 %, and increased net O3 production rates by 31 %, manifesting that the reduction of HCHO and its precursors' emissions would effectively mitigate O3 pollution. Therefore, the pollution characteristics and photochemical effects of HCHO provided significant guidance for future photochemical pollution control in relatively clean areas.
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Affiliation(s)
- Taotao Liu
- Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, China; Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, China; University of Chinese Academy of Sciences, Beijing, China
| | - Yiling Lin
- Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, China; College of Chemical Engineering, Huaqiao University, Xiamen, China
| | - Jinsheng Chen
- Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, China; Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, China.
| | - Gaojie Chen
- Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, China; Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, China; University of Chinese Academy of Sciences, Beijing, China
| | - Chen Yang
- Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, China; Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, China; University of Chinese Academy of Sciences, Beijing, China
| | - Lingling Xu
- Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, China; Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, China
| | - Mengren Li
- Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, China; Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, China
| | - Xiaolong Fan
- Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, China; Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, China
| | - Fuwang Zhang
- Environmental Monitoring Center of Fujian, Fuzhou, China
| | - Youwei Hong
- Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, China; Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, China.
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Physical-Optical Properties of Marine Aerosols over the South China Sea: Shipboard Measurements and MERRA-2 Reanalysis. REMOTE SENSING 2022. [DOI: 10.3390/rs14102453] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Aerosols play an important role in the Earth–atmosphere system. Their impacts on the weather and climate are highly dependent on spatiotemporal distributions as well as physical-optical properties. Physical-optical properties of the aerosols over the Asian continent have been widely investigated, but there are relatively few observations in maritime locations, especially the South China Sea (SCS). Here, with the combination of in situ ship-based observations from June and July 2019 as well as long-term MERRA-2 reanalysis datasets from January 2012 to December 2021, the physical and optical properties of marine aerosols in the SCS are explored. The impacts of meteorological factors, particularly frontal systems, on the aerosol properties are further analyzed based on detailed observations. The observed results show that aerosols are vertically concentrated below 3 km and the extinction coefficient reaches the maximum value of 0.055 km−1 near 480 m. Moreover, the particles are composed of an accumulation and a coarse particle mode, and they conform to the lognormal distribution. The synoptic-scale case study demonstrates that both the cold front and stationary front lead to an increase in aerosol optical thickness (AOD), which is due to the enhanced wind speed and the hygroscopic growth of fine particles, respectively. The long-term analysis indicates that AOD decreases from northwest to southeast with the increasing distance away from the continent, and it reflects higher values in spring and winter than in summer and autumn. Sulfate and sea salt dominate AOD in this region when compared with other components. The overall AOD shows a significant negative trend of −0.0027 year−1. This work will help us further understand the physical and optical properties of marine aerosols over the SCS and then contribute to quantifying the aerosol radiative forcing in the future.
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Wang G, Zhu Z, Zhao N, Wei P, Li G, Zhang H. Variations in characteristics and transport pathways of PM 2.5 during heavy pollution episodes in 2013-2019 in Jinan, a central city in the north China Plain. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2021; 284:117450. [PMID: 34049162 DOI: 10.1016/j.envpol.2021.117450] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Revised: 05/14/2021] [Accepted: 05/21/2021] [Indexed: 05/24/2023]
Abstract
The characteristics and transport pathways of air masses vary during heavy pollution episodes (HPEs). Three categories of HPEs have been defined: HPE Ι, II, and III, corresponding to HPE durations of 1, 2, and at least 3 days, respectively. Sixty HPEs were investigated in this study. The number of HPEs decreased from 2013 to 2017 and then increased from 2017 to 2019, dominated by emission reductions and meteorological conditions. The average and maximum PM2.5 (i.e., aerodynamic diameter of <2.5 μm) concentrations during those HPEs in 2019 decreased by 5.6%-11.8% and 11.9%-38.5%, respectively, compared with those in 2013. The longer the duration of an HPE, the higher the PM2.5 concentration. Secondary inorganic aerosol concentrations and their contents in PM2.5 during HPE Ⅲ were found to be higher than those during HPEs Ι and Ⅱ, as secondary transformations of precursor gases are more intense during long-term HPEs. The dominant trajectories of airflow arriving in Jinan originated from the southern and southeastern regions during HPEs, realized using the Hybrid Single Particle Lagrangian Integrated Trajectory. The trajectories from the north and west of Jinan contained the highest PM2.5 concentrations of 323.3-432.1 μg/m3 during HPE Ⅲ, although these trajectories only contributed 5.6%-11.1% of the total dominant transport pathways, while those in trajectories from the northwest were highest during HPEs Ι and Ⅱ. The highest contributions of air masses from short distances were found during HPE Ⅲ, of 77.8%, while they were only 65.6% and 47.8% during HPEs Ι and II, respectively. More attention should be given to transport pathways within the short distance from Jinan. Therefore, enhancing regional cooperation in Jinan and surrounding regions (particularly in the south, southeast, northwest, west, and north) is critical for improving air quality in the North China Plain.
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Affiliation(s)
- Gang Wang
- Department of Environmental and Safety Engineering, College of Chemical Engineering, China University of Petroleum (East China), Qingdao, 266580, China.
| | - Zhongyi Zhu
- Department of Environmental and Safety Engineering, College of Chemical Engineering, China University of Petroleum (East China), Qingdao, 266580, China
| | - Na Zhao
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science and Engineering, Institute of Atmospheric Sciences, Fudan University, Shanghai, 200433, China
| | - Peng Wei
- Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
| | - Guohao Li
- Municipal Research Institute of Environmental Protection, Beijing, 100037, China; Key Laboratory of Beijing on VOC Pollution Control Technology and Application of Urban Atmosphere, Beijing, 100037, China
| | - Hanyu Zhang
- School of Ecology and Environment, Beijing Technology and Business University, Beijing, 100048, China
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Li Z, Wang Y, Xu Z, Cao Y. Characteristics and sources of atmospheric pollutants in typical inland cities in arid regions of central Asia: A case study of Urumqi city. PLoS One 2021; 16:e0249563. [PMID: 33878117 PMCID: PMC8057588 DOI: 10.1371/journal.pone.0249563] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2020] [Accepted: 03/22/2021] [Indexed: 12/26/2022] Open
Abstract
The arid zone of central Asia secluded inland and has the typical features of the atmosphere. Human activities have had a significant impact on the air quality in this region. Urumqi is a key city in the core area of the Silk Road and an important economic center in Northwestern China. The urban environment is playing an increasingly important role in regional development. To study the characteristics and influencing factors of the main atmospheric pollutants in Urumqi, this study selected Urumqi's daily air quality index (AQI) data and observation data of six major pollutants including fine particulate matter (PM2.5), breathable particulate matter (PM10), sulfur dioxide (SO2), nitrogen dioxide (NO2), carbon monoxide (CO), and ozone (O3_8h) from 2014 to 2018 in conjunction with meteorological data to use a backward trajectory analysis method to study the main characteristics of atmospheric pollutants and their sources in Urumqi from 2014 to 2018. The results showed that: (1) From 2014 to 2018, the annual average of PM2.5, PM10, SO2, NO2 and CO concentrations showed a downward trend, and O3_8h concentrations first increased, then decreased, and then increased, reaching the highest value in 2018 (82.15 μg·m-3); The seasonal changes of PM2.5, PM10, SO2, NO2 and CO concentrations were characterized by low values in summer and fall seasons and high values in winter and spring seasons. The concentration of O3_8h, however, was in the opposite trend, showing the high values in summer and fall seasons, and low values in winter and spring seasons. From 2014 to 2018, with the exception of O3_8h, the concentration changes of the other five major air pollutants were high in December, January, and February, and low in May, June, and July; the daily changes showed a "U-shaped" change during the year. The high-value areas of the "U-shaped" mode formed around the 50th day and the 350th day. (2) The high-value area of AQI was from the end of fall (November) to the beginning of the following spring (March), and the low-value area was from April to October. It showed a U-shaped change trend during the year and the value was mainly distributed between 50 and 100. (3) The concentrations of major air pollutants in Urumqi were significantly negatively correlated with precipitation, temperature, and humidity (P<0.01), and had the highest correlation coefficients with temperature. (4) Based on the above analysis results, this study analyzed two severe pollution events from late November to early December. Analysis showed that the PM2.5/PM10 ratio in two events remained at about 0.1 when the pollution occurred, but was higher before and after the pollution (up to 1.46). It was shown that the pollution was a simple sandstorm process. Backward trajectory analysis clustered the airflow trajectories reaching Urumqi into 4 categories, and the trajectories from central Asia contributed the maximum values of average PM2.5 and PM10 concentrations.
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Affiliation(s)
- Zongying Li
- College of Resource and Environmental Science, Xinjiang University, Urumqi, China
- Key Laboratory of Oasis Ecology, Ministry of Education, Urumqi, China
| | - Yao Wang
- Institute of Desert Meteorology, China Meteorological Administration, Urumqi, China
| | - Zhonglin Xu
- College of Resource and Environmental Science, Xinjiang University, Urumqi, China
- Key Laboratory of Oasis Ecology, Ministry of Education, Urumqi, China
| | - Yue’e Cao
- School of Environmental and Geographical Sciences, Shanghai Normal University, Shanghai, China
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Teleconnection between the Asian Polar Vortex and surface PM 2.5 in China. Sci Rep 2020; 10:19431. [PMID: 33173049 PMCID: PMC7655842 DOI: 10.1038/s41598-020-76414-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Accepted: 10/27/2020] [Indexed: 12/02/2022] Open
Abstract
Atmospheric fine particulate matter (PM2.5) pollutions are of particular concern because of their direct and indirect harm to humans and organisms. China has suffered from severe air pollution for the past ten years, related to heavy pollution emissions and compounded by the effects of atmospheric circulation. This study applied statistical methods, observational data of ground pollutants, and meteorological data to analyze the impact of large-scale atmospheric circulations on PM2.5 pollution over China. Empirical orthogonal function (EOF) analysis was used to evaluate the main PM2.5 patterns and total contributions of the leading four EOFs. The results indicate that the total contributions of the leading four EOFs accounted for 50.5% of the total variance, reflecting four main types of PM2.5 pollution, namely, overall pollution phase, north–south phase, east–west phase and north–center–south phase, with contributions of 28.4%, 9.7%, 6.5% and 5.9%, respectively. We selected indices of the Asian Polar Vortex (APV) to analyze the impact of large-scale atmospheric circulations on PM2.5 pollution over China. The most pronounced APV control occurred in Beijing and its surroundings, specifically, along the Bohai Sea and the Northeast Plain.
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Wang Q, Fang J, Shi W, Dong X. Distribution characteristics and policy-related improvements of PM 2.5 and its components in six Chinese cities. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2020; 266:115299. [PMID: 32818727 DOI: 10.1016/j.envpol.2020.115299] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2019] [Revised: 07/22/2020] [Accepted: 07/23/2020] [Indexed: 05/21/2023]
Abstract
This study presents the distribution characteristics and possible sources of fine particulate matter (PM2.5) and its components, as well as policy-related pollution reduction in the Chinese cities of Jinan, Shijiazhuang (SJZ), Chengdu, Wuxi, Wuhan, and Harbin (HRB). PM2.5 samples were collected using mid-volume samplers during the autumn of 2017 in all six cities. The samples were analyzed to determine the ambient PM2.5 compositions, including the concentrations of water-soluble inorganic ions (WSIIs), carbonaceous aerosols, and elements concentrations. The chemical ratios of organic carbon to elemental carbon and nitrate to sulfate as well as the enrichment factors of elements were calculated to establish the possible sources of PM2.5 in all six cities. The highest PM2.5 concentration was 152 μg/m3 in SJZ, while the lowest concentration was 47 μg/m3 in HRB. During the sampling period in these six cities, the PM2.5 concentrations exceeded the World Health Organization recommended daily average air quality guidelines by 2.4-6.1 times, and WSIIs, carbonaceous aerosols, and elements accounted for 31.8%-61.6%, 9.8%-35.1%, and 0.9%-2.5% of the PM2.5, respectively. In 2013, the Chinese government formulated the Air Pollution Prevention and Control Action Plan (APPCAP) for controlling air pollution, and effective measures have been implemented since then. Compared with previous studies conducted during 2009-2013 before the implementation of the APPCAP, the concentrations of PM2.5 and most of its components decreased to varying degrees, and large changes in the chemical ratios of PM2.5 components were observed. These results indicate that PM2.5 sources vary among these six cities and that China has improved the ambient air quality in these cities through the implementation of air pollution control policies. The APPCAP have achieved considerable results in continuously reducing pollution concentrations, although the air pollution concentrations observed in this study remain high compared with those of other countries.
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Affiliation(s)
- Qiong Wang
- China CDC Key Laboratory of Environment and Population Health, National Institute of Environmental Health, Chinese Center for Disease Control and Prevention, Beijing, 100021, China
| | - Jianlong Fang
- China CDC Key Laboratory of Environment and Population Health, National Institute of Environmental Health, Chinese Center for Disease Control and Prevention, Beijing, 100021, China
| | - Wanying Shi
- China CDC Key Laboratory of Environment and Population Health, National Institute of Environmental Health, Chinese Center for Disease Control and Prevention, Beijing, 100021, China
| | - Xiaoyan Dong
- China CDC Key Laboratory of Environment and Population Health, National Institute of Environmental Health, Chinese Center for Disease Control and Prevention, Beijing, 100021, China.
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