Mineralogical characterization of airborne individual particulates in Beijing PM10

This work mainly focuses on the mineralogical study of particulate matter（PM10） in Beijing. Samples were collected on polycarbonate filter from April, 2002 to March, 2003 in Beijing urban area. Scanning electronic microscopy coupled with energy dispersive X-ray（SEM/EDX） was used to investigate individual mineral particles in Beijing PM10. 1454 individual mineral particulates from 48 samples were analysed by SEM/EDX. The results revealed that mineral particulates were complex and heterogeneous. 38 kinds of minerals in PM10 were identified. The clay minerals, of annual average percentage of 30.1%, were the main composition among the identified minerals, and illite/smectite was the main composition in clay minerals, reaching up to 35%. Annual average percentage of quartz, calcite, compound particulates, carbonates were 13.5%, 10.9%, 11.95%, 10.31%, respectively. Annual average percentage less than 10% were gypsum, feldspar, dolomite, and so on. Fluorite, apatite, halite, barite and chloridize zinc（ZnCl2） were firstly identified in Beijing PM10. Sulfurization was found on surface of mineral particles, suggested extensive atmospheric reaction in air during summer.

Spatial and Temporal Variation of Particulate Matter (PM10 and PM2.5) and Its Health Effects during the Haze Event in Malaysia

This study aims to assess and compare levels of particulate matter(PM10 and PM2.5)in urban and industrial areas in Malaysia during haze episodes,which typically occur in the south west monsoon season.The high concentrations of atmospheric particles are mainly due to pollution from neighbouring countries.Daily PM concentrations were analysed for urban and industrial areas including Alor Setar,Tasek,Shah Alam,Klang,Bandaraya Melaka,Larkin,Balok Baru,and Kuala Terengganu in 2018 and 2019.The analysis employed spatiotemporal to examine how PM levels were distributed.The data summary revealed that PM levels in all study areas were right-skewed,indicating the occurrence of high particulate events.Significant peaks in PM concentrations during haze events were consistently observed between June and October,encompassing the south west monsoon and inter-monsoon periods.The study on acute respiratory illnesses primarily focused on Selangor.Analysis revealed that Klang had the highest mean number of inpatient cases for acute exacerbation of bronchial asthma(AEBA)and acute exacerbation of chronic obstructive pulmonary disease(AECOPD)with values of 260.500 and 185.170,respectively.Similarly,for outpatient cases of AEBA and AECOPD,Klang had the highest average values of 41.67 and 14.00,respectively.Shah Alam and Sungai Buloh did not show a significant increase in cases during periods of biomass burning.The statistical analysis concluded that higher concentrations of PM were associated with increased hospital admissions,particularly from June to September,as shown in the bar diagram.Haze episodes were associated with more healthcare utilization due to haze-related respiratory illnesses,seen in higher inpatient and outpatient visits(p<0.05).However,seasonal variability had minimal impact on healthcare utilization.These findings offer a comprehensive assessment of PM levels during historic haze episodes,providing valuable insights for authorities to develop policies and guidelines for effective monitoring and mitigation of the negative impacts of haze events.

Characteristics and fate behavior of environmentally persistent free radicals in atmospheric particulate matter

Background,aim,and scope Environmentally persistent free radicals(EPFRs)have received significant attention due to their longer lifetime and stable existence in various environments.The strong environmental migration ability of particulate matter allows EPFRs to migrate over long-distance transport,thereby impacting the quality of the local atmospheric environment.Additionally,EPFRs can also adhere to atmospheric particles and interact with typical gaseous pollutants to affect atmospheric chemical reactions.EPFRs can produce some reactive organic species,promoting oxidative stress in the human body,damaging biological macromolecules and ultimately affecting the organism health.EPFRs are considered as a novel type of pollutant that affects human health.Despite their significance,there are few literatures available on the characteristics and fate behaviors of EPFRs up to date.Therefore,supplemental reviews are crucial for providing comprehensive understanding of EPFRs.Materials and methods This review summarizes the characteristics of EPFRs in particulate matter,outlines the generation mechanism and influencing factors of EPFRs,and the impacts of EPFRs on environmental quality and organism health.Results The content of EPFRs in particulate matter ranges from 1017 to 1020 spins∙g−1.Due to the strong mobility of atmospheric particulate matter,the long-term exposure to high levels of EPFRs may aggravate the impact of particulate matter on human health.The interaction between EPFRs and typical gaseous pollutants can alter their fate and influence atmospheric chemical reactions.EPFRs are mainly produced by transition metal elements and substituted aromatic hydrocarbons through electron transfer.Additionally,the chemical bond rupture of organic substances through heat treatment or ultraviolet radiation can also produce EPFRs,and heterogeneous reactions are capable producing them as well.The production of EPFRs is not only influenced by transition metal elements and precursors,but also by various environmental factors such as oxygen,temperature,light radiation,and relative humidity.Discussion EPFRs in atmospheric particulates matters are usually rich in fine particulates with obvious seasonal and regional variations.They can easily enter the human respiratory tract and lungs with inhalable particulates,thereby increasing the risk of exposure.Additionally,EPFRs in atmospheric particulates can interact with some typical gaseous pollutants,impacting the life and fate of EPFRs in the atmosphere,and alter atmospheric chemical reactions.Traditionally,EPFRs are generated by transition metal elements and substituted aromatic hydrocarbons undergoing electron transfer in the post-flame and cool-zone regions of combustion systems and other thermal processes to remove HCl,H_(2)O or CO groups,ultimately produce semiquinones,phenoxyls,and cyclopentadienyls.Recent studies have indicated that EPFRs can also be generated under the conditions of without transition metal elemental.Organics can also produce EPFRs through chemical bond rupture during heat treatment or light radiation conditions,as well as through some heterogeneous reactions and photochemical secondary generation of EPFRs.The presence or absence of oxygen has different effects on the type and yield of EPFRs.The concentration,type,and crystal type of transition metal elements will affect the type,content,and atmospheric lifetime of EPFRs.It is generally believed that the impact of transition metal element types on EPFRs is related to the oxidation-reduction potential.The combustion temperature or heat treatment process significantly affects the type and amount of EPFRs.Factors such as precursor loading content,pH conditions,light radiation and relative humidity also influence the generation of EPFRs.EPFRs can interact with pollutants in the environment during their migration and transformation process in environmental medium.This process accelerates the degradation of pollutants and plays a crucial role in the migration and transformation of organic pollutants in environmental media.The reaction process of EPFRs may lead to the production of reactive oxygen species(ROS)such as∙OH,which can induce oxidative stress,inflammation and immune response to biological lung cells and tissues,leading to chronic respiratory and cardiopulmonary dysfunction,cardiovascular damage and neurotoxic effects,ultimately impacting the health of organisms.Conclusions The interaction mechanism between EPFRs in particulate matter and gaseous pollutants remains unclear.Furthermore,research on the generation mechanism of EPFRs without the participation of transition metals is not comprehensive,and the detection of EPFRs is limited to simple qualitative categories and lack accurate qualitative analysis.Recommendations and perspectives Further research should be conducted on the generation mechanism,measurement techniques,migration pathways,and transformation process of EPFRs.It is also important to explore the interaction between EPFRs in atmospheric particulate matter and typical gaseous pollutants.

Impact of Urban 3D Morphology on Particulate Matter 2.5(PM2.5) Concentrations:Case Study of Beijing, China

Urban particulate matter 2.5(PM2.5)pollution and public health are closely related,and concerns regarding PM2.5 are widespread.Of the underlying factors,the urban morphology is the most manageable.Therefore,investigations of the impact of urban three-dimensional(3D)morphology on PM2.5 concentration have important scientific significance.In this paper,39 PM2.5 monitoring sites of Beijing in China were selected with PM2.5 automatic monitoring data that were collected in 2013.This data set was used to analyze the impacts of the meteorological condition and public transportation on PM2.5 concentrations.Based on the elimination of the meteorological conditions and public transportation factors,the relationships between urban 3D morphology and PM2.5 concentrations are highlighted.Ten urban 3D morphology indices were established to explore the spatial-temporal correlations between the indices and PM2.5 concentrations and analyze the impact of urban 3D morphology on the PM2.5 concentrations.Results demonstrated that road length density(RLD),road area density(RAD),construction area density(CAD),construction height density(CHD),construction volume density(CVD),construction otherness(CO),and vegetation area density(VAD)have positive impacts on the PM2.5 concentrations,whereas water area density(WAD),water fragmentation(WF),and vegetation fragmentation(VF)(except for the 500 m buffer)have negative impacts on the PM2.5 concentrations.Moreover,the correlations between the morphology indices and PM2.5 concentrations varied with the buffer scale.The findings could lay a foundation for the high-precision spatial-temporal modelling of PM2.5 concentrations and the scientific planning of urban 3D spaces by authorities responsible for controlling PM2.5 concentrations.

Feature Analysis of the Atmospheric Particulate Pollutants (PM_(10) and PM_(2.5)) in Wenzhou City

[ Objective] The research aimed to analyze characteristics of the atmospheric particulate pollutants （ PMlo and PM2.s） in Wenzhou City. [Method] We analyzed interannual change rule of the dust haze in Wenzhou during 1978 -2008. Moreover, we respectively set monitoring points in urban district, industrial park and beauty spot of Wenzhou in summer and winter of 2010. Element, ion and polycyclic aromatic hydrocarbon com- positions and morphology of the particulate matter were analyzed. [ Result] Dust haze in Wenzhou City mainly appeared in winter and spring, which was related to local meteorological condition. In summer and winter, both PMlo and PM2.s concentrations presented the characteristic of industrial park 〉 commercial area 〉 beauty spot. Chain-like particle aggregates and ultrafine particles were main composition of the atmospheric particulate matter in Wenzhou. Contribution rate of the spherical particle amount was smaller than metropolis, which was related to local industry and traffic. Fe element had the most content in particulate matter. Mass concentration was mainly composed of 6 elements, such as Na, Si, S, K, Ca and Fe. Total concentration of the six elements occupied 70% -80% of the 16 elements. SO^- and NH4＊ in particulate matter were higher. They were mainly from human activity. Main compositions of the polycyclic aromatic hydrocarbon were naphthalene, anthracene, benzo （b） fluoranthene, indeno （1,2, 3-cd） pyrene and benzo （g, h, i） perylene, which was related to abrupt increase of the motor vehicle. [ Condusion] The research provided scientific basis and technology support for controlling atmospheric particulate matter pollution in Wenzhou City by government and related department.

徐州市PM_(2.5)和PM_(10)相关性分析

徐州市是典型的煤炭工业城市,目前,大气污染依然比较严重,颗粒物是影响区域大气质量改善的主要污染物。本文以徐州市为研究区,利用国控监测站、省控监测站获得的细颗粒物(PM_(2.5))、可吸入颗粒物(PM_(10))质量浓度数据,结合大气灰霾超级站在线监测数据,综合运用数理统计和相关性分析,探讨PM_(2.5)和PM_(10)的时间变化特征,明确二者的相关性。作为老工业基地,徐州市必须充分发挥资源优势和创新优势,大力发展新型能源和双碳产业,从而削减PM2.5和PM10的排放量,改善区域生态环境。

Short-term exposure to fine particulate matter and hospital admission for stroke:a meta-analysis

Objective Air pollution is an important risk factor for cardiovascular diseases throughout the world.Fine particulate matter(PM)air pollution alone is responsible for over three million deaths each year.Large and growing literature has explored whether short-term exposure to fine particulate matter is associated with stroke,but results from prior studies have been inconsistent.To fill this gap,we assessed the evidence quantitatively from epidemiological time-series studies published worldwide and determined whether short-term exposure to fine particulate matter(<2.5μm or<10μm)diameter[PM2.5 and PM10]was associated with increased risk of hospital admission for stroke(including ischemic and hemorrhagic stroke).

Human Health Risks from Exposure to Heavy Metals of Suspended Particulate Matter around the Tongon Gold Mine, Côte d’Ivoire

The Tongon mine, the largest gold mine in C?te d’Ivoire, has been in operation since April 2010. However, to our knowledge to date, no study has been conducted on metallic contamination in suspended particulate matter (PM10 and PM2.5) where there is a lack of information on the carcinogenic and non-carcinogenic risk to human health associated with the exposure of populations in the Tongon area to these pollutants. The general objective of this study is to evaluate the level of contamination of PM10;PM2.5 by heavy metals and their impact on the health of populations exposed to these pollutants in the Tongon gold mine area. The sampling and measurement of suspended particulate matter (PM10 and PM2.5) were done using a MiniVol TAS passive air sampler. Heavy metal concentrations were determined by inductively coupled plasma mass spectroscopy (Nex ION 2000 ICP-MS, USA). The results indicate that the average concentrations of suspended particles (PM2.5 and PM10) obtained are all above the recommended exposure limits. In addition, among the heavy metals contained in the suspended particles, the concentrations of arsenic and nickel are high and all above the standard limit values. The assessment of the health risks related to the inhalation of PM10 particles reveals that their inhalation over a long period could cause a carcinogenic risk.

Effect of Varying Temperature and Oxygen on Particulate Matter Formation in Oxy-Biomass Combustion

Offsetting particulate matter emissions has become a critical global aim as there are concerted efforts to deal with environmental and energy poverty challenges.This study consists of investigations of computing emissions of particulate matter from biomass fuels in various atmospheres and temperatures.The laboratory setup included a fixed bed electric reactor and a particulate matter(PM)measuring machine interfaced with the flue gas from the fixed bed reactor combustion chamber.The experiments were conducted at seven different temperatures(600℃-1200℃)and six incremental oxygen concentrations(21%-100%).Five biomass types were studied;A-cornstalk,B-wood,C-wheat straw,D-Rice husk,E-Peanut shell,each pulverized to a size of approximately 75 microns.The study shows that PM emitted during char combustion is consistently higher than that emitted during the de-volatilization.During de-volatilization,increase in temperature leads to linear decrease in PM emission between atmospheres of 21%O_(2)to 50%O_(2),thereafter,between 70%O_(2)to 100%O_(2);increase in temperature leads to a rise in PM emission.The average PM formation from all the five considered biomass is relatively comparable however,with differing atmospheres and temperatures,the fibrous and low-density biomass forms more PM.During char combustion,the study shows that at oxygen levels of 21%,70%,90%and 100%,increase in temperature leads to increased PM emission.The increase in oxygen concentration and temperature increases the rate of combustion hence diminishing the time of combustion.

A Study of the Correlation between the Concentration of Particulate Matter and Green Area Ratio Measured through a Portable Monitoring System: With Particular Focus on the Case of Dalseo-Gu, Daegu Metropolitan City

This study analyzed the relationship between the measured concentration of particulate matter (PM) and green area, which is an important spatial factor affecting urban PM concentration and even more carbon neutral in cities. In order to investigate the effects of green area, the green area ratio (GAR) is used and correlated with particulate matter. As a result of analyzing the correlation between GAR and PM concentration using the measured PM data, it was found that there was a positive correlation between the two variables. Hence, the higher the GAR, the lower the PM concentration. It can be said that the introduction of spatial elements with high GAR scores, such as parks and forests in cities, is effective in reducing PM concentration. In this study, a portable PM monitoring system using a vehicle for PM measurement was also established and operated. As a result, it was found that a PM monitoring system using a light-scattering sensor is an effective PM measurement method that can be used at the local government level. It was also found that a follow-up study is needed in the future to identify the PM mitigation functions of urban green areas according to the detailed characteristics of green areas as well as various environmental factors. This study can be used in air quality improvement activities and efforts as reference data by policy decision makers and in the field of environmental planning associated with the removal of airborne particulate matter pollution in urban areas.

Using a Parafoil Kite for Measurement of Variations in Particulate Matter—A Kite-Based Dust Profiling Approach

This paper reports on the use of a kite-based system for measuring low-altitude particulate matter (PM) concentrations over grassland in Inner Mongolia. The motivation came from PM-concentration measurements at heights below 3 m over non-erodible surfaces which showed constant concentrations and made flux calculations relatively uncertain. One aim was the quantification of wind-driven matter fluxes across ecosystem boundaries, where the relevant layer can be assumed at heights below 100 m. Compared to other measurement techniques (e.g. LIDAR, towers and airborne systems) kite-based systems represent an inexpensive, highly flexible research tool which is well-suited for application in remote sites. The basis of the introduced system is a 4 m2 Parafoil kite which has enough lifting capacity to carry equipment of about 6 kg at wind velocities between 3 ms-1 to nearly 20 ms-1. A self-adjusting platform was constructed to balance moves and to carry a portable Environmental Dust Monitor (EDM), anemometer and a GPS receiver. So, all parameters necessary for a vertical profile of dust fluxes could be measured. In the first flights the applied kite-based dust profiling system (KIDS) was examined according to general technical application problems. Firstly, the influence of diverse surface characteristics, the flying condition and height-stability was tested. The result suggests that surface characteristics in general have a higher influence than the optimal wind velocity, which ranged from 9 ms-1 to 17 ms-1. Secondly, uncertainties in the measured data were quantified and assessed. The uncertainties in wind velocity measurements due to motion in horizontal and vertical direction were not higher than 0.45% - 0.65% and 1.8% - 2.2% during the kite ascent. The outcome of the study illustrates the suitable application of KIDS for low-altitude measurements in remote sites.

Assessment of Inhalable Particulate Matter Associated with a Refinery in Curacao

Inhalation and atmospheric pollution studies have focused on particulate matter due to correlations and associations with various morbidities and mortalities. This research analyzed ambient concentrations of inhalable particulate matter (PM10) on the island of Cura&ccedil;ao in order to evaluate through comparative literature analysis and recommended public health guidelines the potential health risks. Available hourly, daily and monthly PM10 measurements were accessed from June 2010 through December 2014 from a local air monitoring station in Willemstad. Mean annual concentrations of PM10 (31 - 122 μg/m3) in Cura&ccedil;ao are among the highest reported globally, demonstrating an increasing trend over time and exceed current public health guidelines recommended by local and international agencies. While the epidemiological evidence is inadequate to infer a causal association between health effects and long-term exposures of the measured PM10 concentrations, the results indicate that emissions controls are not adequate for compliance with international exposure standards.

Indoor and Outdoor Particulate Matter Exposure of Rural Interior Alaska Residents

To assess the exposure of residents in rural communities in the Yukon Flats to particulate matter of 2.5 μm or less in diameter (PM2.5), both indoor and outdoor concentration observations were carried out from March to September 2019 in Ft. Yukon, Alaska. Indoor concentrations were measured at 0.61 m (breathing level during sleeping) in homes and at 1.52 m heights (breathing level of standing adult) in homes and office/commercial buildings. Air quality was better at both heights in cabins than frame homes both during times with and without surface-based inversions. In frame houses, concentrations were higher at 0.61 m than 1.52 m, while the opposite is true typically for cabins. Differences between shoulder season and summer indoor concentrations in residences were related to changes in heating, subsistence lifestyle and mosquito repellents. In summer, office and commercial buildings, air quality decreased due to increased indoor emissions related to increased use of equipment and mosquito pics as well as more merchandise. During summer indoor concentrations reached unhealthy for sensitive groups to hazardous conditions for extended times that even exceeded the high outdoor concentrations. Due to nearby wildfires, July mean outdoor concentrations were 55.3 μg·m-3 which exceeds the 24-h US National Ambient Air Quality Standard of 35 μg·m-3. Indoor and outdoor concentrations correlated the strongest with each other for office/commercial buildings, followed by frame houses and cabins. Office/commercial buildings with temperature monitors had one to two orders of magnitude lower concentrations than those without.

TSP-PM_(10)-PM_(2.5)-2型中流量大气颗粒物采集系统的开发和应用

自行开发并研制了 TSP-PM1 0 -PM2 .5-2型中流量 TSP、PM1 0 、PM2 .5大气颗粒物采集系统 ,是目前中国唯一可以采集 TSP、PM1 0 、PM2 .5样品并提供足够的样品量进行大气颗粒物化学成分分析的中流量大气颗粒物采集器。该系统精心设计和加工的限流孔可以保持完全固定的流量 ,保证切割粒径的稳定 ,减小采样的误差并方便操作。该系统已经成功地应用于 2 0多个城市和地区大气颗粒物的监测和研究中 ,为研究大气颗粒物的污染状况和来源提供了有效的技术手段和支持。

大气矿物质PM10-2.5生物活性与生态毒性效应研究进展

介绍了构成空气污染的最主要来源大气矿物质颗粒物PM10～2.5。通过分析PM对生物体内细胞的各种生化作用、自由基及尘载微生物毒性的研究,结合动物实验和流行病学调查,阐述PM的危害机理。指出目前对PM2.5以及更细的颗粒物如纳米物质的生物活性与效应研究较少,未把PM自身特性的生物响应纳入研究内容,尚未建立细颗粒物对生物机体(如微生物和低等植物)危害的总体结果与评价;今后应从界面反应等多因子重点揭示其毒理学机理,以多学科对PM生物活性和生态毒性进行深入研究。

北京市可吸入颗粒物(PM_(10))中单颗粒的矿物组成特征

使用SEM/EDX对北京不同月份采集的可吸入颗粒物 (PM10 )中的 14 5 4个矿物颗粒进行了识别和统计。结果显示 ,矿物颗粒的种类十分复杂 ,可以鉴定出的矿物有 38种 ,其中以粘土矿物的含量最高 ,年平均值为 30 .1% ;粘土矿物中以伊利石 /蒙皂石混层为主 ,占粘土矿物总数的 35 % ;石英、方解石、复合颗粒、碳颗粒的年均值分别为13.5 %、10 .9%、11.95 %、10 .31% ;年平均含量小于 10 %的矿物有石膏、长石、白云石等 ;首次检测出萤石、磷灰石、岩盐、重晶石、氯化锌等矿物。研究还发现 ,硫化现象可以发生在不同矿物颗粒表面 ,且这种现象主要发生在夏季 。

可吸入颗粒物PM_(10)对细胞间隙连接通讯的抑制作用

[目的 ]研究直径≤ 1 0 μm的可吸入大气颗粒物 (PM1 0 )对细胞间隙连接通讯的影响 ,探讨PM1 0 的非遗传毒性作用。 [方法 ]用大流量采样器 ,采集城区交通干道旁约 1 8m高度处大气中的PM1 0 。超纯水超声提取、低温真空冷冻干燥制备PM1 0 悬液。采用细胞代谢协同试验和染料划痕试验观察PM1 0 对中国仓鼠肺成纤维V79细胞以及人肺成纤维细胞间隙连接通讯的影响。 [结果 ]PM1 0 抑制V79细胞的代谢协同作用 ,使V79- 细胞的存活率增高 ,在 1 0～ 1 0 0mg/L剂量范围内 ,与对照组比较 ,克隆形成数明显增高 ,有剂量 反应关系 (r=0 94,P <0 0 5)。细胞划痕实验结果显示 ,在PM1 01 0～ 1 0 0mg/L剂量范围内 ,在人肺成纤维细胞中荧光染料扩散距离随剂量的增加而减小 (7 5～ 2 1 61mm) ,与对照组(2 6 56mm)比较 ,差异显著。 [结论 ]PM1 0 能抑制细胞间隙连接通讯 ,提示可能在癌症的发生过程中起促进作用。

澳门地区PM_(10)粒度分布的分形特征研究

采集澳门地区不同区域大气PM10样品,根据单颗粒图像分析方法分析了PM10的粒径分布,计算了各采样点PM10粒度分布的分形维数,分析讨论了PM10粒度分布分形维数的变化与粒度分布的关系,分析了粒度分布分形维数表征的澳门大气PM10不同采样点、不同季节的粒度整体分布及其影响因素之间的关系。结果表明,澳门地区PM10粒度分布的分形维数在2.05-3.95之间,夏季PM10的粒度分布分形维数（2.88）大于冬季（2.63）,表明夏季PM10的粒度普遍较冬季的细。同一季节不同区域大气PM10的粒度也有较大变化,夏季时,澳门岛的总体颗粒物、矿物颗粒和烟尘颗粒物的分形维数较氹仔岛的偏大,即澳门岛的颗粒物比氹仔岛偏细,而冬季则相反,冬季时,澳门岛的总体颗粒物、矿物颗粒和烟尘颗粒物的分形维数较氹仔岛的偏小。

细颗粒物PM2.5对大鼠IL-10、IL-22表达的影响及百令胶囊的干预作用

目的观察细颗粒物(PM 2.5)对大鼠肺损伤的影响,探讨中药百令胶囊对肺损伤的保护作用。方法2019年9—10月于河北省人民医院动物研究中心进行实验。将40只Wistar雄性大鼠按随机数字表法分为空白对照组、PM2.5染毒组及PM2.5+百令胶囊低、中、高剂量组5组。除空白对照组外,其余4组每3天将PM2.5混悬液(10 m g/kg)经大鼠气管内滴入进行PM2.5染毒,共10次。在PM2.5染毒基础上,百令胶囊组分别以低(0.25 g/kg)、中(0.5 g/kg)、高(1 g/kg)3种不同剂量的百令胶囊悬液每日连续给予大鼠灌胃,共28 d;通过HE染色观察各组大鼠肺组织炎性病理变化,并应用ELISA法测定血清中白介素10(IL-10)、IL-22蛋白含量,利用实时荧光定量PCR法检测大鼠肺组织IL-10、IL-22 mRNA的表达。结果大鼠肺组织病理检查发现,PM2.5染毒组可见大量慢性炎性细胞浸润,百令胶囊干预各组较PM2.5染毒组炎性细胞浸润情况明显减轻。与空白对照组比较,PM2.5染毒组大鼠血清IL-10水平明显降低(t/P=27.758/0.000),血清IL-22水平明显升高(t/P=28.190/0.000)。与PM2.5染毒组比较,百令胶囊干预各组随剂量的增加,血清IL-10水平逐渐升高(F/P=224.867/0.000),而血清IL-22水平则逐渐下降(F/P=149.115/0.000)。Pearson相关分析表明:血清IL-10与IL-22水平呈负相关(r=0.960,P<0.05)。实时荧光定量PCR法检测法结果显示,与空白对照组比较,PM2.5染毒组肺组织IL-10 mRNA表达水平明显降低(t/P=61.342/0.000),肺组织IL-22 mRNA水平明显升高(t/P=55.298/0.000);与PM2.5染毒组比较,百令胶囊干预各组随剂量的增加,肺组织IL-10 mRNA水平逐渐升高(F/P=1131.931/0.000),而IL-22 mRNA水平则逐渐下降(F/P=604.257/0.000)。结论PM 2.5短期暴露可造成大鼠肺部炎性损害,百令胶囊可通过促进IL-10的分泌及表达,以及抑制IL-22的生成,对肺部起到保护作用。

可吸入颗粒物(PM_(10))空间特点与城市热岛格局的关系分析

采用成都市可吸入颗粒物(PM10)小时浓度的空间分布实例,结合NOAA/AVHRR(National Oceanic and Atmospheric Administration/Advanced Very High Resolution Radiometer)遥感数据所获的城市热岛温度场格局图,结果发现:下午环形热岛出现时城市中心区的PM10浓度较低,二、三环路附近的浓度相对较高,城区西南部尤其明显。分析认为,环形热岛改变了城市近地层的温度场和流场结构,在城郊结合部造成"双重循环",容易导致污染物在这些地方聚集。