A large body of evidence links ambient fine particulates (PM<sub>2.5</sub>) to chronic disease. Efforts continue to be made to improve large scale estimation of this pollutant for within-urban environments...A large body of evidence links ambient fine particulates (PM<sub>2.5</sub>) to chronic disease. Efforts continue to be made to improve large scale estimation of this pollutant for within-urban environments and sparsely monitored areas. Still questions remain about modeling choices. The purpose of this study was to evaluate the performance of spatial only models in predicting national monthly exposure estimates of fine particulate matter at different time aggregations during the time period 2000-2009 for the contiguous United States. Additional goals were to evaluate the difference in prediction between federal reference monitors and non-reference monitors, assess regional differences, and compare with traditional methods. Using spatial generalized additive models (GAM), national models for fine particulate matter were developed, incorporating geographical information systems (GIS)-derived covariates and meteorological variables. Results were compared to nearest monitor and inverse distance weighting at different time aggregations and a comparison was made between the Federal Reference Method and all monitors. Cross-validation was used for model evaluation. Using all monitors, the cross-validated R<sup>2</sup> was 0.76, 0.81, and 0.82 for monthly, 1 year, and 5-year aggregations, respectively. A small decrease in performance was observed when selecting Federal Reference monitors only (R<sup>2</sup> = 0.73, 0.78, and 0.80 respectively). For Inverse distance weighting (IDW), there was a significantly larger decrease in R<sup>2</sup> (0.68, 0.71, and 0.73, respectively). The spatial GAM showed the weakest performance for the northwest region. In conclusion, National exposure estimates of fine particulates at different time aggregations can be significantly improved over traditional methods by using spatial GAMs that are relatively easy to produce. Furthermore, these models are comparable in performance to other national prediction models.展开更多
Based on on-line single particle aerosol mass spectrometry (SPAMS) with high time resolution, the sources of atmospheric fine particu- late matter in Nan'ao County were analyzed. The results showed that during the ...Based on on-line single particle aerosol mass spectrometry (SPAMS) with high time resolution, the sources of atmospheric fine particu- late matter in Nan'ao County were analyzed. The results showed that during the monitoring period from March 24 to 27 in 2015, the primary source of fine particulate matter in Nao'ao County was motor vehicle exhaust, that is, 24.7% of fine particulates were from motor vehicle exhaust, followed by biomass burning (17.2%), fire coal (17.2%), and sea salt (13.3%). The proportions of fire coal and sea salt revealed the peculiarity of sources of atmospheric fine particulate matter in Nan'ao County. Therefore, it is suggested that some measures should be adopted to limit tourist traffic to reduce the adverse impact of motor vehicle exhaust on ambient air quality in Nan'ao County.展开更多
Objective In recent decades,China has implemented a series of policies to address air pollution.We aimed to assess the health effects of these policies on stroke burden attributable to ambient fine particulate matter(...Objective In recent decades,China has implemented a series of policies to address air pollution.We aimed to assess the health effects of these policies on stroke burden attributable to ambient fine particulate matter(PM_(2.5)).Methods Joinpoint regression was applied to explore the temporal tendency of stroke burden based on data from the Global Burden of Disease 2019 study.Results The age-standardized rates of disability-adjusted life year(DALY)for stroke attributable to ambient PM2.5 in China,increased dramatically during 1990-2012,subsequently decreased at an annual percentage change(APC)of-1.98[95% confidence interval(CI):-2.26,-1.71]during 2012-2019.For ischemic stroke(IS),the age-standardized DALY rates doubled from 1990 to 2014,and decreased at an APC of-0.83(95%CI:-1.33,-0.33)during 2014-2019.Intracerebral hemorrhage(ICH)showed a substantial increase in age-standardized DALY rates from 1990 to 2003,followed by declining trends,with APCs of-1.46(95%CI:-2.74,-0.16)during 2003-2007 and-3.33(95%CI:-3.61,-3.06)during 2011-2019,respectively.Conversely,the age-standardized DALY rates for subarachnoid hemorrhage(SAH)generally declined during 1990-2019.Conclusion Our results clarified the dynamic changes of the ambient PM_(2.5)-attributable stroke burden in China during 1990-2019,highlighting the health effects of air quality improvement policies.展开更多
Objective This study aimed to investigate the association of ambient PM_(2.5)exposure with blood pressure(BP)at the population level in China.Methods A total of 14,080 participants who had at least two valid blood pre...Objective This study aimed to investigate the association of ambient PM_(2.5)exposure with blood pressure(BP)at the population level in China.Methods A total of 14,080 participants who had at least two valid blood pressure records were selected from the China Health and Retirement Longitudinal Survey during 2011–2015.Their long-term PM_(2.5)exposure was assessed at the geographical level,on the basis of a regular 0.1°×0.1°grid over China.A mixed-effects regression model was used to assess associations.Results Each decrease of 10μg/m^(3)in the 1 year-mean PM_(2.5)concentration(FPM1Y)was associated with a decrease of 1.24[95%confidence interval(CI):0.84–1.64]mmHg systolic BP(SBP)and 0.50(95%CI:0.25–0.75)mmHg diastolic BP(DBP),respectively.A robust association was observed between the long-term decrease in PM_(2.5)and decreased BP in the middle-aged and older population.Using a generalized additive mixed model,we further found that SBP increased nonlinearly overall with FPM1Y but in an approximately linear range when the FPM1Y concentration was<70μg/m^(3);In contrast,DBP increased approximately linearly without a clear threshold.Conclusion Efficient control of PM_(2.5)air pollution may promote vascular health in China.Our study provides robust scientific support for making the related air pollution control policies.展开更多
The paper analyzed the concentrations of trace metals in fine and respirable particulates (fine-PM<sub>1</sub> and PM<sub>2.5</sub>;respirable-PM<sub>10</sub>) to determine baseline...The paper analyzed the concentrations of trace metals in fine and respirable particulates (fine-PM<sub>1</sub> and PM<sub>2.5</sub>;respirable-PM<sub>10</sub>) to determine baseline concentrations in the ambient air and the factors impacting its distribution such as land use and time of year when levels may be concerning to public health. Measurements of particulates along with meteorological parameters were made at four sites over the heavily populated west coast of Trinidad (10<span style="font-size:10.0pt;font-family:;" "=""><span style="color:#4F4F4F;font-family:"font-size:14px;white-space:normal;background-color:#FFFFFF;">°</span></span>32'N, 61<span style="font-size:10.0pt;font-family:;" "=""><span style="color:#4F4F4F;font-family:"font-size:14px;white-space:normal;background-color:#FFFFFF;">°</span></span>18'W) during March ’15-May ’16, representing rural, urban, mixed background and industrial land uses. The study found mean levels of trace metals to be highest at the industrial and urban stations. Public health exceedances (referenced to the Canadian AAQ public health standards <a href="#ref23">(Ontario-MoE, 2012)</a>) were measured for beryllium, cadmium, chromium, iron, manganese and nickel (in PM<sub>10</sub>). Iron, manganese and nickel, most associated with particulates at the industrial station, were in frequent exceedance. Beryllium—concentrated in coarse PM (PM<sub>2.5-10</sub>) with only a single measured exceedance at the mixed background station likely poses minimal threat to the health of the nearby population. Cadmium—concentrated in fine PM which peaked once only at the rural station was likely due to an irregular event within a narrow timeframe during the time of sampling. Iron and manganese were frequently above the Canadian public health threshold, but predominated in the coarse PM fraction, suggesting localised sources. Nickel, concentrated in the fine PM fraction, was frequently in exceedance particularly at the industrial station. Cadmium and nickel are genotoxic and should be regulated in order to reduce the burden of toxic carcinogens to which the population can be exposed.展开更多
Gestational hypertension(GH)is a common complication during pregnancy.GH is regarded as a potential public health challenge for pregnant women and infants.Limited evidence has linked ambient air pollution to an increa...Gestational hypertension(GH)is a common complication during pregnancy.GH is regarded as a potential public health challenge for pregnant women and infants.Limited evidence has linked ambient air pollution to an increased GH risk.However,most of the studies were conducted in developed countries,with inconsistent results obtained.The present study was performed to explore whether exposure to particulate matters with an aerodynamic diameter≤2.5(PM2.5)and ozone(O3)was related to elevated odds of GH in a Chinese population.This population-based cohort study involved 38115 pregnant women in Wuhan,China.All information was collected from the Wuhan Maternal and Child Health Management Information System,using standardized quality control.The daily air pollutant data for PM2.5 and O3 were obtained from the 20 monitoring stations of the Wuhan Environmental Monitoring Center during 2014.The nearest monitor approach was applied to individual exposure assessment of PM2.5 and O3 for each participant.After adjusting for major confounders and other air pollutants,a 10μg/m^3 increase in PM25 and O3 concentrations was found to correlate to a 1.14-fold[95%confidence interval(95%CI):1.09,1.20]and a 1.05-fold(95%CI:1.02,1.07)increase in GH risk,respectively.Additionally,stronger relationships between GH risk and PM25 and O3 exposure were observed in women who conceived in winter and summer,respectively.These findings suggest that air pollutants may contribute to the development of GH.展开更多
Fine particulate matter and eight heavy metals (Ni, Co, Cu, Pb, Cd, Cr, Mn, and Zn) concentrations were determined in air samples collected from three industrial sites in northern Nigeria using a Handheld Portable Par...Fine particulate matter and eight heavy metals (Ni, Co, Cu, Pb, Cd, Cr, Mn, and Zn) concentrations were determined in air samples collected from three industrial sites in northern Nigeria using a Handheld Portable Particle Counter for PM<sub>2.5</sub> and PM<sub>10</sub> with model number CW-HAT 200 and a High Volume Respirable Dust Sampler (APM 460 NL) in conjunction with an Atomic Absorption Spectrophotometer (Serial No. AA0904M046) Flame Test. The results of the fine particulates ranged from 11.0 - 46.0 μg<span style="color:#4F4F4F;font-family:" font-size:14px;white-space:normal;background-color:#f7f7f7;"="">.</span>m<span style="font-family:Verdana, Helvetica, Arial;white-space:normal;background-color:#FFFFFF;"><sup>-</sup></span><sup>3</sup> for PM<sub>2.5</sub> and 22.0 - 88 <span style="white-space:normal;"> μg</span><span font-size:14px;white-space:normal;background-color:#f7f7f7;"="" style="white-space: normal;color: rgb(79, 79, 79);">.</span><span style="white-space:normal;">m</span><span style="white-space:normal;font-family:Verdana, Helvetica, Arial;background-color:#FFFFFF;"><sup>-</sup></span><sup style="white-space:normal;">3</sup><sup></sup> for PM<sub>10</sub> across all the industrial sites investigated. Most of these results exceeded the WHO permissible levels of 25.0 <span style="white-space:normal;"> μg</span><span font-size:14px;white-space:normal;background-color:#f7f7f7;"="" style="white-space: normal;color: rgb(79, 79, 79);">.</span><span style="white-space:normal;">m</span><span style="white-space:normal;font-family:Verdana, Helvetica, Arial;background-color:#FFFFFF;"><sup>-</sup></span><sup style="white-space:normal;">3</sup> and 50.0 <span style="white-space:normal;"> μg</span><span font-size:14px;white-space:normal;background-color:#f7f7f7;"="" style="white-space: normal;color: rgb(79, 79, 79);">.</span><span style="white-space:normal;">m</span><span style="white-space:normal;font-family:Verdana, Helvetica, Arial;background-color:#FFFFFF;"><sup>-</sup></span><sup style="white-space:normal;">3</sup> for PM<sub>2.5</sub> and PM<sub>10</sub> and thus pose threats to people living and working close to these sites. The concentration of the heavy metals studied were found to be within WHO/EU set standards except for the concentrations of Ni, Pb, and Cd that exceeded the set standard by WHO/EU with toxicity potential >1 in the Terytex industry, Kano and Grand Cereals, Jos. Strong positive correlations were found between the fine particulates concentrations and heavy metals in all the studied sites suggesting that common anthropogenic sources contributed to the fine particulates and heavy metals recorded from the industrial areas. We suggested the installation of electrostatic precipitators to combat fine particulates emission from the stack and also recommended a proper legislative framework by the government to regulate and control industrial fugitive emissions to protect human health.展开更多
The nested-grid capability of the global chemical transport model GEOS-Chem, with a horizontal resolution of 1/4°× 5/16° (latitude x longitude), was used to identify the chemical species whose reducti...The nested-grid capability of the global chemical transport model GEOS-Chem, with a horizontal resolution of 1/4°× 5/16° (latitude x longitude), was used to identify the chemical species whose reductions made the largest contributions to decreases in PM2.s concentrations (fine particulate matter, diameter 〈 2.5μm, defined in this study as the sum of sulfate, nitrate, ammonium, black carbon, and organic carbon aerosols) in Beijing during the 2014 Asia-Pacific Economic Cooperation (APEC) summit. A number of numerical experiments were carried out for the period 15 October-29 November 2014. The model reproduced the observed daily variations of concentrations of PM2.s and gas-phase species (carbon monoxide, nitrogen dioxide, and sulfur dioxide). Simulated PM2.s concentrations decreased by 55.9%-58.5% during the APEC period, compared to other periods in October and November 2014, which agreed closely with measurements. Sensitivity results showed that emissions control measures regarding nitrogen oxides and organic carbon over North China led to the largest reductions in PM2.s concentrations in Beijing during the APEC summit, which led to overall reductions in the PM2.5 concentration of Beijing by 5.7% and 4.6%, respectively. The control of ammonia emissions was found to be able to greatly reduce PM2.5 concentrations in the whole of North China during the APEC meeting.展开更多
There is much literature on the effects of fine particulate matter (PM2.5) on respiratory and cardiovascular health. However, few studies have evaluated the impact of PM2.5 on a population living in the vicinity of a ...There is much literature on the effects of fine particulate matter (PM2.5) on respiratory and cardiovascular health. However, few studies have evaluated the impact of PM2.5 on a population living in the vicinity of a massive deposit of mine tailings. A longitudinal panel study was performed to evaluate the association between exposure to PM2.5 and acute effects on lung function in schoolchildren from November 2012 to May 2013. Ambient levels of PM2.5 and its metal composition were measured. Lung function was evaluated using spirometric testing. Associations were quantified using GEE multilevel analysis controlling for confounders by using different lag time periods. The chemical characterization of PM2.5 had high levels of S > Na > Cl > Ca > Si > Fe > Al > Mg > K > Cu > Ti > and Zn, which would be associated with metals present in tailings. We found a negative association between the temporal variation of PM2.5 and changes in lung function specifically on forced vital capacity. Our results suggest that schoolchildren exposed to fine particulate matter from tailings deposited in the bay of Chanaral have their forced vital capacity decreased, which would affect their present and future lung development, increasing the risk of developing chronic respiratory diseases.展开更多
This study constructs a quasi-natural experiment based on the expansion of the Yangtze River Delta urban agglomeration(YRDUA) of China in 2010 to investigate the impact and inner mechanism of urban agglomeration expan...This study constructs a quasi-natural experiment based on the expansion of the Yangtze River Delta urban agglomeration(YRDUA) of China in 2010 to investigate the impact and inner mechanism of urban agglomeration expansion on fine particulate matter(PM_(2.5)) concentrations through propensity scores in difference-in-differences models(PSM-DID) using panel data from 286 prefecturelevel cities in China from 2003 to 2016. The results show that 1) urban agglomeration expansion contributes to an overall decrease in PM_(2.5)concentration, which is mainly achieved from the original cities. For the new cities, on the other hand, the expansion significantly increases the local PM_(2.5)concentration. 2) In the long term, the significant influence of urban agglomeration expansion on PM_(2.5)concentration lasts for three years and gradually decreases. A series of robustness tests confirm the applicability of the PSM-DID model.3) Cities with weaker government regulation, a better educated population and higher per capita income present stronger PM_(2.5)reduction effects. 4) Urban agglomeration expansion affects the PM_(2.5)concentration mainly through industrial transfer and population migration, which cause a decrease in the PM_(2.5)concentration in the original cities and an increase in the PM_(2.5)concentration in the new cities.Corresponding policy suggestions are proposed based on the conclusions.展开更多
Through the integration and analysis platform of particulate matter components,a preliminary comparison was conducted on the pollution contribution of the three winter transit air masses in December to environmental q...Through the integration and analysis platform of particulate matter components,a preliminary comparison was conducted on the pollution contribution of the three winter transit air masses in December to environmental quality,and the changes and related relationships of water-soluble ions and particulate matter elements were analyzed.The results showed that winter transit air masses had a significant impact on the air quality in Hengyang.In the quantitative comparison of the primary pollutant contribution during the transit period of air masses,local sources and transit sources each accounted for half,and the impact of transit source on ambient air quality was much greater than that of seasonal base increase.Fine particulate matter was closely related to secondary ions,and particulate matter was closely related to primary ions.The transit of air masses promoted the improvement of secondary ion conversion rate,and the unit increment of fine particulate matter was greater than that of particulate matter.During the transit period,the mass concentrations of most water-soluble ions and most particulate matter elements maintained synchronous growth,with a superimposed effect.The composition ratio of organic carbon and nitrate ions increased,while the composition ratio of ammonia and sulfate ions decreased.Both disposable ions and secondary conversions in the composition of PM_(2.5)had increases and decreases.The high conversion rate of nitrate and the high composition ratio of ammonia radical in Hengyang indicated that transportation source factors had a significant impact on the local environmental quality of Hengyang.展开更多
Background: Despite the adverse effects of ambient fine particulate matter (PM_(2.5) ) on type 2 diabetes and the beneficial role of physical activity (PA), the influence of PM_(2.5) on the relationship between PA and...Background: Despite the adverse effects of ambient fine particulate matter (PM_(2.5) ) on type 2 diabetes and the beneficial role of physical activity (PA), the influence of PM_(2.5) on the relationship between PA and type 2 diabetes remains unclear.Methods: In this prospective study with 71,689 participants, PA was assessed by a questionnaire and was categorized into quartiles for volume and three groups for intensity. Long-term PM_(2.5) exposure was calculated using 1-km resolution satellite-based PM_(2.5) estimates. PM_(2.5) exposure and PA's effect on type 2 diabetes were assessed by cohort-stratified Cox proportional hazards models, individually and in combination.Results: In 488,166 person-years of follow-up, 5487 incident type 2 diabetes cases were observed. The association between PA and type 2 diabetes was modified by PM_(2.5) . Compared with the lowest quartile of PA volume, the highest quartile was associated with reduced type 2 diabetes risk in low PM_(2.5) stratification (≤65.02 μg/m^(3)) other than in high PM_(2.5) stratification (>65.02 μg/m^(3)), with the hazard ratio (HR) of 0.75 (95% confidence interval [CI]: 0.66-0.85) and 1.10 (95% CI: 0.99-1.22), respectively. Similar results were observed for PA intensity. High PM_(2.5) exposure combined with the highest PA levels increased the risk of type 2 diabetes the most (HR= 1.79, 95% CI: 1.59-2.01 for PA volume;HR = 1.82, 95% CI: 1.64-2.02 for PA intensity).Conclusion: PA could reduce type 2 diabetes risk in low-pollution areas, but high PM_(2.5) exposure may weaken or even reverse the protective effects of PA. Safety and health benefits of PA should be thoroughly assessed for long-term polluted residents.展开更多
Objective To evaluate the antagonistic effects of N-acetylcysteine(NAC)on mitogen-activated protein kinases(MAPK)pathway activation,oxidative stress and inflammatory responses in rats with lung injury induced by fine ...Objective To evaluate the antagonistic effects of N-acetylcysteine(NAC)on mitogen-activated protein kinases(MAPK)pathway activation,oxidative stress and inflammatory responses in rats with lung injury induced by fine particulate matter(PM2.5).Methods Forty eight male Wistar rats were randomly divided into six groups:blank control group(C1),water drip control group(C2),PM2.5 exposed group(P),low-dose NAC treated and PM2.5 exposed group(L),middle-dose NAC treated and PM2.5 exposed group(M),and high-dose NAC treated and PM2.5 exposed group(H).PM2.5 suspension(7.5 mg/kg)was administered tracheally once a week for four times.NAC of 125 mg/kg,250 mg/kg and 500 mg/kg was delivered intragastrically to L,M and H group respectively by gavage(10 ml/kg)for six days before PM2.5 exposure.The histopathological changes and human mucin 5 subtype AC(MUC5AC)content in lung tissue of rats were evaluated.We investigated IL-6 in serum and bronchoalveolar lavage fluid(BALF)by Enzyme-linked immunosorbent assay(ELISA),MUC5AC in lung tissue homogenate by ELISA,glutathione peroxidase(GSH-PX)in serum and BALF by spectrophotometry,and the expression of p-ERK1/2,p-JNK1/2 and p-p38 proteins by Western blot.All the measurements were analyzed and compared statistically.Results Lung tissue of rats exposed to PM2.5 showed histological destruction and increased mucus secretion of bronchial epithelial cells.Rats receiving NAC treatment showed less histological destruction and mucus secretion.Of P,L,M and H group,MUC5AC in lung tissue,IL-6 in serum and BALF were higher than controls(C1 and C2)(all P<0.05),with the highest levels found in the P group and a decreasing trend with increase of NAC dose.The activity of GSH-PX in serum and BALF of PM2.5 exposed rats(P,L,M and H)was lower than that of controls(all P<0.05),with higher activities found in NAC treated rats(L,M,and H),and an increasing trend with increase of NAC dose.The expressions of p-ERK1/2,p-JNK1/2 and p-p38 proteins in PM2.5 exposed lung tissue(P,L,M and H)was higher than controls(all P<0.05),with decreased levels and dose dependent downregulation found in NAC treated rats.Conclusion NAC can antagonize major MAPK pathway activation,lung oxidative stress and inflammatory injury induced by PM2.5 in rats.展开更多
华北大气污染区域化正在对农业生态区域产生显著影响,为了了解华北农业地区大气细颗粒物PM_(2.5)的季节分布特征,2017年7月、9月、12月以及2018年4月在中国科学院禹城农业生态综合实验站进行分季节PM_(2.5)样品采集,并测定分析了样品中3...华北大气污染区域化正在对农业生态区域产生显著影响,为了了解华北农业地区大气细颗粒物PM_(2.5)的季节分布特征,2017年7月、9月、12月以及2018年4月在中国科学院禹城农业生态综合实验站进行分季节PM_(2.5)样品采集,并测定分析了样品中31种化学成分。结果表明,碳质气溶胶总体的浓度水平为13.11±8.37μg m^(−3),有机碳(OC)冬春季节浓度较高,元素碳(EC)浓度在秋冬季节较高。同时OC/EC的比值在秋季明显偏低,表明在秋季二次碳质气溶胶对PM_(2.5)贡献较小。水溶性离子浓度总体在冬季最高。NO_(3)^(-)/SO_(4)^(2-)比值在夏季明显偏低为0.69,华北地区夏季固定点源对大气污染的贡献相对较高。PM_(2.5)中金属元素以Na、Mg、Al、Ca、K、Fe等地壳元素为主,具有致癌风险的Co、Cr、Ni、Pb、As等金属元素年均浓度为0.32±0.24 ng m^(−3)、5.40±5.42 ng m^(−3)、10.23±7.46 ng m^(−3)、42.23±27.75 ng m^(−3)、5.66±3.79 ng m^(−3)。受体模型(PMF)计算结果表明,PM_(2.5)的主要来源为二次污染源、生物质燃烧源、燃煤燃油源、柴油车尾气和土壤源,贡献率分别达37.1%、18.2%、14.2%、9.4%和7.9%,表明农业区细颗粒物污染受到华北工业、农业与自然排放的多重影响。展开更多
The aim of present research is to study the dispersion of air pollutants using the air quality model, AERMOD and to predict the impact of pollutants (PM<sub>10</sub>, NO<sub>2</sub> and CO) at ...The aim of present research is to study the dispersion of air pollutants using the air quality model, AERMOD and to predict the impact of pollutants (PM<sub>10</sub>, NO<sub>2</sub> and CO) at the receptor level released from Gas Based Power Plant (GBPP). The net-concentrations including monitored data plus predicted values of PM<sub>10</sub>, NO<sub>2</sub> and CO would be increased from base value 75 to 77.61 μg/m<sup>3</sup> with an increase of 3.48%, 22 to 26.66 μg/m<sup>3</sup> with an increase of 21.18% and 428 to 538.37 μg/m<sup>3</sup> with an increase of 25.79% respectively. The study of hill effect showed that it had profound impact upon the dispersion of pollutants and the ratio (with hill and without hill) of each pollutant was 3.89 for PM<sub>10</sub> (24 hr), 2.40 for NO<sub>2</sub> (24 hr) and 13.98 for CO (1 hr). The natural gas based plant not only decreases the pollution level but also reduces the hospital treatment cost and protects the public health. The modeling results suggest that the GBPP could be a clean technology as replacement of coal power plants located in the city which pollute the environment considerably in spite of control measures installed.展开更多
Objective To verify whether Warthin-Starry (WS) silver method could detect the air particulate matter (PM)/dust particles (Ps) located within the macrophages in situ. Methods There were 26 autopsy cases that res...Objective To verify whether Warthin-Starry (WS) silver method could detect the air particulate matter (PM)/dust particles (Ps) located within the macrophages in situ. Methods There were 26 autopsy cases that resulted from cerebral hemorrhage (group A), silicosis (group B), and fetal death during pregnancy (group C). Samples were collected separately and serial sections were prepared from the lungs and lymph nodes and stained with hematoxylin and eosin (HE), WS silver, immunohistochemistry of CD68. Furthermore, ultrathin sections were taken from the WS positive serial sections of groups A and B. Ps were observed under a transmission electron microscope (TEM) and the elements of Ps were measured by X-ray spectrum analysis (X-RSA). Results In both groups A and B, WS staining was positive for the larger and fine Ps, the so called "dust cells", but HE staining was almost negative for fine Ps. In group C, no larger or fine Ps were found. Immunohistochemical staining of CD68 certified that the "dust cells" containing Ps were macrophages. The results of TEM and X-RSA proved that the structure and elements of Ps belonged to PM indeed. Conclusion WS staining is a better than HE staining in showing the location of PM within macrophages.展开更多
To investigate aerosol optical properties in the Beijing metropolitan area, aerosol absorption coefficient (Ab), scattering coefficient (So), and fine particulate matter (PM2.5) were measured in the Beijing urba...To investigate aerosol optical properties in the Beijing metropolitan area, aerosol absorption coefficient (Ab), scattering coefficient (So), and fine particulate matter (PM2.5) were measured in the Beijing urban area from 20 May to 30 August 2009. The average Ab, So, single scat- tering albedo (SSA), and PM2.5 concentration were 58.0±39.5 M m^-1, 343.5±353.7 M m 1, 0.80±0.10 and 63.6+50.0 μg m^-3, respectively, during the observation period. Ab, Sc, and SSA all showed single peak diurnal variations, with their maximum values being measured at 0500, 1000, and 1300 local time, respectively. Ab and Sc had a strong positive correlation with PM2.5, and Ab, Sc, and PM25 all had positive correlations with relative humidity and negative correlations with wind speed.展开更多
Objective Fine particulate matter(PM^(2.5))is an air pollutant that has become of great concern in recent years.Numerous studies have found that PM^(2.5)may contribute to lung cancer,but the pathogenesis has not yet b...Objective Fine particulate matter(PM^(2.5))is an air pollutant that has become of great concern in recent years.Numerous studies have found that PM^(2.5)may contribute to lung cancer,but the pathogenesis has not yet been fully elucidated.In this study,we explored the roles of exosomes from bronchial epithelial cells in PM^(2.5)-promoted lung cancer metastasis.Methods Exosomes were isolated from cell supernatants.An animal model of lung metastasis(established by tail vein injection of A549-luc)and in vitro studies with lung cancer cell lines were used to investigate the effects of exosomes derived from PM^(2.5)-treated human bronchial epithelial cells(PHBE-exo).Results The animal experiments revealed that PHBE-exo-treated mice showed stronger luciferase activity and a larger relative metastatic region in the lungs,thus indicating that PHBE-exo promoted the metastatic potential of lung cancer.Additionally,PHBE-exo promoted the migration,invasion and epithelial-to-mesenchymal transition of lung cancer cells,in a manner mediated by activation of c-Jun Nterminal kinase.Conclusion These results implied that PM^(2.5)may promote the development of lung cancer through exosomes derived from bronchial epithelial cells,thus providing a potential interventional target for lung cancer.These findings broadened our understanding of cancer-promoting mechanisms of environmental pollutants.展开更多
In China, the level of ambient fine particulate matter (PM_(2.5)) pollution far exceeds the air quality standards recommended by the World Health Organization. Moreover, the health effects of PM_(2.5) exposure have be...In China, the level of ambient fine particulate matter (PM_(2.5)) pollution far exceeds the air quality standards recommended by the World Health Organization. Moreover, the health effects of PM_(2.5) exposure have become a major public health issue. More than half of PM_(2.5)-related excess deaths are caused by cardiopulmonary disease, which has become a major health risk associated with PM_(2.5) pollution. In this review, we discussed the latest epidemiological advances relating to the health effects of PM_(2.5) on cardiopulmonary diseases in China, including studies relating to the effects of PM_(2.5) on mortality, morbidity, and risk factors for cardiovascular and respiratory diseases. These data provided important evidence to highlight the cardiopulmonary risk associated with PM_(2.5) across the world. In the future, further studies need to be carried out to investigate the specific relationship between the constituents and sources of PM_(2.5) and cardiopulmonary disease. These studies provided scientific evidence for precise reduction measurement of pollution sources and public health risks. It is also necessary to identify effective biomarkers and elucidate the biological mechanisms and pathways involved;this may help us to take steps to reduce PM_(2.5) pollution and reduce the incidence of cardiopulmonary disease.展开更多
This review aimed to systematically summarize the epidemiological literature on the cardiorespiratory effects of PM_(2.5)published during the 13^(th) Five-Year Plan period(2016-2020)in China.Original articles publishe...This review aimed to systematically summarize the epidemiological literature on the cardiorespiratory effects of PM_(2.5)published during the 13^(th) Five-Year Plan period(2016-2020)in China.Original articles published between January 1,2016 and June 30,2021 were searched in PubMed,Web of Science,the China National Knowledge Internet Database and Wanfang Database.Random-or fixed-effects models were used to pool effect estimates where appropriate.Of 8558 records identified,145 met the full eligibility criteria.A 10μg/m^(3) increase in short-term PM_(2.5)exposure was significantly associated with increases of 0.70%,0.86%,0.38%and 0.96%in cardiovascular mortality,respiratory mortality,cardiovascular morbidity,and respiratory morbidity,respectively.The specific diseases with significant associations included stroke,ischemic heart disease,heart failure,arrhythmia,chronic obstructive pulmonary disease,pneumonia and allergic rhinitis.The pooled estimates per 10μg/m^(3) increase in long-term PM_(2.5)exposure were 15.1%,11.9%and 21.0%increases in cardiovascular,stroke and lung cancer mortality,and 17.4%,11.0%and 4.88%increases in cardiovascular,hypertension and lung cancer incidence respectively.Adverse changes in blood pressure,heart rate variability,systemic infiammation,blood lipids,lung function and airway infiammation were observed for either short-term or long-term PM_(2.5)exposure,or both.Collectively,we summarized representative exposure-response relationships between short-and long-term PM_(2.5)exposure and a wide range of cardiorespiratory outcomes applicable to China.The magnitudes of estimates were generally smaller in short-term associations and comparable in long-term associations compared with those in developed countries.Ourfindings are helpful for future standard revisions and policy formulation.There are still some notable gaps that merit further investigation in China.展开更多
文摘A large body of evidence links ambient fine particulates (PM<sub>2.5</sub>) to chronic disease. Efforts continue to be made to improve large scale estimation of this pollutant for within-urban environments and sparsely monitored areas. Still questions remain about modeling choices. The purpose of this study was to evaluate the performance of spatial only models in predicting national monthly exposure estimates of fine particulate matter at different time aggregations during the time period 2000-2009 for the contiguous United States. Additional goals were to evaluate the difference in prediction between federal reference monitors and non-reference monitors, assess regional differences, and compare with traditional methods. Using spatial generalized additive models (GAM), national models for fine particulate matter were developed, incorporating geographical information systems (GIS)-derived covariates and meteorological variables. Results were compared to nearest monitor and inverse distance weighting at different time aggregations and a comparison was made between the Federal Reference Method and all monitors. Cross-validation was used for model evaluation. Using all monitors, the cross-validated R<sup>2</sup> was 0.76, 0.81, and 0.82 for monthly, 1 year, and 5-year aggregations, respectively. A small decrease in performance was observed when selecting Federal Reference monitors only (R<sup>2</sup> = 0.73, 0.78, and 0.80 respectively). For Inverse distance weighting (IDW), there was a significantly larger decrease in R<sup>2</sup> (0.68, 0.71, and 0.73, respectively). The spatial GAM showed the weakest performance for the northwest region. In conclusion, National exposure estimates of fine particulates at different time aggregations can be significantly improved over traditional methods by using spatial GAMs that are relatively easy to produce. Furthermore, these models are comparable in performance to other national prediction models.
基金Supported by the Science and Technology Funding Project of Shantou City,China([2015]106)
文摘Based on on-line single particle aerosol mass spectrometry (SPAMS) with high time resolution, the sources of atmospheric fine particu- late matter in Nan'ao County were analyzed. The results showed that during the monitoring period from March 24 to 27 in 2015, the primary source of fine particulate matter in Nao'ao County was motor vehicle exhaust, that is, 24.7% of fine particulates were from motor vehicle exhaust, followed by biomass burning (17.2%), fire coal (17.2%), and sea salt (13.3%). The proportions of fire coal and sea salt revealed the peculiarity of sources of atmospheric fine particulate matter in Nan'ao County. Therefore, it is suggested that some measures should be adopted to limit tourist traffic to reduce the adverse impact of motor vehicle exhaust on ambient air quality in Nan'ao County.
基金supported by National Key Research and Development Program of China(2018YFE0115300,2022YFC3600800,2017YFC0211706)Chinese Academy of Medical Sciences(CAMS)Innovation Fund for Medical Sciences(2021-I2M-1-010)+3 种基金National Natural Science Foundation of China(82073658,82070473)National High Level Hospital Clinical Research Funding(2022-GSP-GG-1,2022-GSP-GG-2)Research Unit of Prospective Cohort of Cardiovascular Diseases and Cancers,CAMS(2019RU038)National Clinical Research Center for Cardiovascular Diseases,Fuwai Hospital,CAMS(NCRC2020006)。
文摘Objective In recent decades,China has implemented a series of policies to address air pollution.We aimed to assess the health effects of these policies on stroke burden attributable to ambient fine particulate matter(PM_(2.5)).Methods Joinpoint regression was applied to explore the temporal tendency of stroke burden based on data from the Global Burden of Disease 2019 study.Results The age-standardized rates of disability-adjusted life year(DALY)for stroke attributable to ambient PM2.5 in China,increased dramatically during 1990-2012,subsequently decreased at an annual percentage change(APC)of-1.98[95% confidence interval(CI):-2.26,-1.71]during 2012-2019.For ischemic stroke(IS),the age-standardized DALY rates doubled from 1990 to 2014,and decreased at an APC of-0.83(95%CI:-1.33,-0.33)during 2014-2019.Intracerebral hemorrhage(ICH)showed a substantial increase in age-standardized DALY rates from 1990 to 2003,followed by declining trends,with APCs of-1.46(95%CI:-2.74,-0.16)during 2003-2007 and-3.33(95%CI:-3.61,-3.06)during 2011-2019,respectively.Conversely,the age-standardized DALY rates for subarachnoid hemorrhage(SAH)generally declined during 1990-2019.Conclusion Our results clarified the dynamic changes of the ambient PM_(2.5)-attributable stroke burden in China during 1990-2019,highlighting the health effects of air quality improvement policies.
文摘Objective This study aimed to investigate the association of ambient PM_(2.5)exposure with blood pressure(BP)at the population level in China.Methods A total of 14,080 participants who had at least two valid blood pressure records were selected from the China Health and Retirement Longitudinal Survey during 2011–2015.Their long-term PM_(2.5)exposure was assessed at the geographical level,on the basis of a regular 0.1°×0.1°grid over China.A mixed-effects regression model was used to assess associations.Results Each decrease of 10μg/m^(3)in the 1 year-mean PM_(2.5)concentration(FPM1Y)was associated with a decrease of 1.24[95%confidence interval(CI):0.84–1.64]mmHg systolic BP(SBP)and 0.50(95%CI:0.25–0.75)mmHg diastolic BP(DBP),respectively.A robust association was observed between the long-term decrease in PM_(2.5)and decreased BP in the middle-aged and older population.Using a generalized additive mixed model,we further found that SBP increased nonlinearly overall with FPM1Y but in an approximately linear range when the FPM1Y concentration was<70μg/m^(3);In contrast,DBP increased approximately linearly without a clear threshold.Conclusion Efficient control of PM_(2.5)air pollution may promote vascular health in China.Our study provides robust scientific support for making the related air pollution control policies.
文摘The paper analyzed the concentrations of trace metals in fine and respirable particulates (fine-PM<sub>1</sub> and PM<sub>2.5</sub>;respirable-PM<sub>10</sub>) to determine baseline concentrations in the ambient air and the factors impacting its distribution such as land use and time of year when levels may be concerning to public health. Measurements of particulates along with meteorological parameters were made at four sites over the heavily populated west coast of Trinidad (10<span style="font-size:10.0pt;font-family:;" "=""><span style="color:#4F4F4F;font-family:"font-size:14px;white-space:normal;background-color:#FFFFFF;">°</span></span>32'N, 61<span style="font-size:10.0pt;font-family:;" "=""><span style="color:#4F4F4F;font-family:"font-size:14px;white-space:normal;background-color:#FFFFFF;">°</span></span>18'W) during March ’15-May ’16, representing rural, urban, mixed background and industrial land uses. The study found mean levels of trace metals to be highest at the industrial and urban stations. Public health exceedances (referenced to the Canadian AAQ public health standards <a href="#ref23">(Ontario-MoE, 2012)</a>) were measured for beryllium, cadmium, chromium, iron, manganese and nickel (in PM<sub>10</sub>). Iron, manganese and nickel, most associated with particulates at the industrial station, were in frequent exceedance. Beryllium—concentrated in coarse PM (PM<sub>2.5-10</sub>) with only a single measured exceedance at the mixed background station likely poses minimal threat to the health of the nearby population. Cadmium—concentrated in fine PM which peaked once only at the rural station was likely due to an irregular event within a narrow timeframe during the time of sampling. Iron and manganese were frequently above the Canadian public health threshold, but predominated in the coarse PM fraction, suggesting localised sources. Nickel, concentrated in the fine PM fraction, was frequently in exceedance particularly at the industrial station. Cadmium and nickel are genotoxic and should be regulated in order to reduce the burden of toxic carcinogens to which the population can be exposed.
基金the National Key Research&Development Program of China(No.2017YFC0212003)the National Natural Science Foundation of China(No.21577043)the Natural Science Foundation of Hubei Province(No.2010CDB08803).
文摘Gestational hypertension(GH)is a common complication during pregnancy.GH is regarded as a potential public health challenge for pregnant women and infants.Limited evidence has linked ambient air pollution to an increased GH risk.However,most of the studies were conducted in developed countries,with inconsistent results obtained.The present study was performed to explore whether exposure to particulate matters with an aerodynamic diameter≤2.5(PM2.5)and ozone(O3)was related to elevated odds of GH in a Chinese population.This population-based cohort study involved 38115 pregnant women in Wuhan,China.All information was collected from the Wuhan Maternal and Child Health Management Information System,using standardized quality control.The daily air pollutant data for PM2.5 and O3 were obtained from the 20 monitoring stations of the Wuhan Environmental Monitoring Center during 2014.The nearest monitor approach was applied to individual exposure assessment of PM2.5 and O3 for each participant.After adjusting for major confounders and other air pollutants,a 10μg/m^3 increase in PM25 and O3 concentrations was found to correlate to a 1.14-fold[95%confidence interval(95%CI):1.09,1.20]and a 1.05-fold(95%CI:1.02,1.07)increase in GH risk,respectively.Additionally,stronger relationships between GH risk and PM25 and O3 exposure were observed in women who conceived in winter and summer,respectively.These findings suggest that air pollutants may contribute to the development of GH.
文摘Fine particulate matter and eight heavy metals (Ni, Co, Cu, Pb, Cd, Cr, Mn, and Zn) concentrations were determined in air samples collected from three industrial sites in northern Nigeria using a Handheld Portable Particle Counter for PM<sub>2.5</sub> and PM<sub>10</sub> with model number CW-HAT 200 and a High Volume Respirable Dust Sampler (APM 460 NL) in conjunction with an Atomic Absorption Spectrophotometer (Serial No. AA0904M046) Flame Test. The results of the fine particulates ranged from 11.0 - 46.0 μg<span style="color:#4F4F4F;font-family:" font-size:14px;white-space:normal;background-color:#f7f7f7;"="">.</span>m<span style="font-family:Verdana, Helvetica, Arial;white-space:normal;background-color:#FFFFFF;"><sup>-</sup></span><sup>3</sup> for PM<sub>2.5</sub> and 22.0 - 88 <span style="white-space:normal;"> μg</span><span font-size:14px;white-space:normal;background-color:#f7f7f7;"="" style="white-space: normal;color: rgb(79, 79, 79);">.</span><span style="white-space:normal;">m</span><span style="white-space:normal;font-family:Verdana, Helvetica, Arial;background-color:#FFFFFF;"><sup>-</sup></span><sup style="white-space:normal;">3</sup><sup></sup> for PM<sub>10</sub> across all the industrial sites investigated. Most of these results exceeded the WHO permissible levels of 25.0 <span style="white-space:normal;"> μg</span><span font-size:14px;white-space:normal;background-color:#f7f7f7;"="" style="white-space: normal;color: rgb(79, 79, 79);">.</span><span style="white-space:normal;">m</span><span style="white-space:normal;font-family:Verdana, Helvetica, Arial;background-color:#FFFFFF;"><sup>-</sup></span><sup style="white-space:normal;">3</sup> and 50.0 <span style="white-space:normal;"> μg</span><span font-size:14px;white-space:normal;background-color:#f7f7f7;"="" style="white-space: normal;color: rgb(79, 79, 79);">.</span><span style="white-space:normal;">m</span><span style="white-space:normal;font-family:Verdana, Helvetica, Arial;background-color:#FFFFFF;"><sup>-</sup></span><sup style="white-space:normal;">3</sup> for PM<sub>2.5</sub> and PM<sub>10</sub> and thus pose threats to people living and working close to these sites. The concentration of the heavy metals studied were found to be within WHO/EU set standards except for the concentrations of Ni, Pb, and Cd that exceeded the set standard by WHO/EU with toxicity potential >1 in the Terytex industry, Kano and Grand Cereals, Jos. Strong positive correlations were found between the fine particulates concentrations and heavy metals in all the studied sites suggesting that common anthropogenic sources contributed to the fine particulates and heavy metals recorded from the industrial areas. We suggested the installation of electrostatic precipitators to combat fine particulates emission from the stack and also recommended a proper legislative framework by the government to regulate and control industrial fugitive emissions to protect human health.
基金supported by the National Basic Research Program of China[973 program,grant number 2014CB441202]the Strategic Priority Research Program of the Chinese Academy of Sciences[grant number XDA05100503]the National Natural Science Foundation of China[grant numbers 41021004,41475137,and 91544219]
文摘The nested-grid capability of the global chemical transport model GEOS-Chem, with a horizontal resolution of 1/4°× 5/16° (latitude x longitude), was used to identify the chemical species whose reductions made the largest contributions to decreases in PM2.s concentrations (fine particulate matter, diameter 〈 2.5μm, defined in this study as the sum of sulfate, nitrate, ammonium, black carbon, and organic carbon aerosols) in Beijing during the 2014 Asia-Pacific Economic Cooperation (APEC) summit. A number of numerical experiments were carried out for the period 15 October-29 November 2014. The model reproduced the observed daily variations of concentrations of PM2.s and gas-phase species (carbon monoxide, nitrogen dioxide, and sulfur dioxide). Simulated PM2.s concentrations decreased by 55.9%-58.5% during the APEC period, compared to other periods in October and November 2014, which agreed closely with measurements. Sensitivity results showed that emissions control measures regarding nitrogen oxides and organic carbon over North China led to the largest reductions in PM2.s concentrations in Beijing during the APEC summit, which led to overall reductions in the PM2.5 concentration of Beijing by 5.7% and 4.6%, respectively. The control of ammonia emissions was found to be able to greatly reduce PM2.5 concentrations in the whole of North China during the APEC meeting.
基金the Chilean National Fund for Research and Development in Health(FONIS N°SA11|2244).
文摘There is much literature on the effects of fine particulate matter (PM2.5) on respiratory and cardiovascular health. However, few studies have evaluated the impact of PM2.5 on a population living in the vicinity of a massive deposit of mine tailings. A longitudinal panel study was performed to evaluate the association between exposure to PM2.5 and acute effects on lung function in schoolchildren from November 2012 to May 2013. Ambient levels of PM2.5 and its metal composition were measured. Lung function was evaluated using spirometric testing. Associations were quantified using GEE multilevel analysis controlling for confounders by using different lag time periods. The chemical characterization of PM2.5 had high levels of S > Na > Cl > Ca > Si > Fe > Al > Mg > K > Cu > Ti > and Zn, which would be associated with metals present in tailings. We found a negative association between the temporal variation of PM2.5 and changes in lung function specifically on forced vital capacity. Our results suggest that schoolchildren exposed to fine particulate matter from tailings deposited in the bay of Chanaral have their forced vital capacity decreased, which would affect their present and future lung development, increasing the risk of developing chronic respiratory diseases.
基金Under the auspices of Chinese National Funding of Social Sciences (No.17AGL005)Institute of Socialism with Chinese Characteristics of Southeast University (No.DDZTZK2021C11)。
文摘This study constructs a quasi-natural experiment based on the expansion of the Yangtze River Delta urban agglomeration(YRDUA) of China in 2010 to investigate the impact and inner mechanism of urban agglomeration expansion on fine particulate matter(PM_(2.5)) concentrations through propensity scores in difference-in-differences models(PSM-DID) using panel data from 286 prefecturelevel cities in China from 2003 to 2016. The results show that 1) urban agglomeration expansion contributes to an overall decrease in PM_(2.5)concentration, which is mainly achieved from the original cities. For the new cities, on the other hand, the expansion significantly increases the local PM_(2.5)concentration. 2) In the long term, the significant influence of urban agglomeration expansion on PM_(2.5)concentration lasts for three years and gradually decreases. A series of robustness tests confirm the applicability of the PSM-DID model.3) Cities with weaker government regulation, a better educated population and higher per capita income present stronger PM_(2.5)reduction effects. 4) Urban agglomeration expansion affects the PM_(2.5)concentration mainly through industrial transfer and population migration, which cause a decrease in the PM_(2.5)concentration in the original cities and an increase in the PM_(2.5)concentration in the new cities.Corresponding policy suggestions are proposed based on the conclusions.
文摘Through the integration and analysis platform of particulate matter components,a preliminary comparison was conducted on the pollution contribution of the three winter transit air masses in December to environmental quality,and the changes and related relationships of water-soluble ions and particulate matter elements were analyzed.The results showed that winter transit air masses had a significant impact on the air quality in Hengyang.In the quantitative comparison of the primary pollutant contribution during the transit period of air masses,local sources and transit sources each accounted for half,and the impact of transit source on ambient air quality was much greater than that of seasonal base increase.Fine particulate matter was closely related to secondary ions,and particulate matter was closely related to primary ions.The transit of air masses promoted the improvement of secondary ion conversion rate,and the unit increment of fine particulate matter was greater than that of particulate matter.During the transit period,the mass concentrations of most water-soluble ions and most particulate matter elements maintained synchronous growth,with a superimposed effect.The composition ratio of organic carbon and nitrate ions increased,while the composition ratio of ammonia and sulfate ions decreased.Both disposable ions and secondary conversions in the composition of PM_(2.5)had increases and decreases.The high conversion rate of nitrate and the high composition ratio of ammonia radical in Hengyang indicated that transportation source factors had a significant impact on the local environmental quality of Hengyang.
基金National Natural Science Foundation of China(Grant/Award Numbers: 82030102, 82373676)National High Level Hospital Clinical Research Funding(Grant/Award Numbers: 2022-GSP-GG-1, 2022-GSP-GG-2)+2 种基金National Key Research and Development Program of China(Grant/Award Numbers: 2017YFC0211700, 2018YFE0115300)Chinese Academy of Medical Sciences Innovation Fund for Medical Sciences(Grant/Award Numbers: 2017-I2M-1-004, 2019-I2M-2-003, 2021-I2M-1-010)Research Unit of Prospective Cohort of Cardiovascular Diseases and Cancers, Chinese Academy of Medical Sciences(Grant/Award Number: 2019RU038)。
文摘Background: Despite the adverse effects of ambient fine particulate matter (PM_(2.5) ) on type 2 diabetes and the beneficial role of physical activity (PA), the influence of PM_(2.5) on the relationship between PA and type 2 diabetes remains unclear.Methods: In this prospective study with 71,689 participants, PA was assessed by a questionnaire and was categorized into quartiles for volume and three groups for intensity. Long-term PM_(2.5) exposure was calculated using 1-km resolution satellite-based PM_(2.5) estimates. PM_(2.5) exposure and PA's effect on type 2 diabetes were assessed by cohort-stratified Cox proportional hazards models, individually and in combination.Results: In 488,166 person-years of follow-up, 5487 incident type 2 diabetes cases were observed. The association between PA and type 2 diabetes was modified by PM_(2.5) . Compared with the lowest quartile of PA volume, the highest quartile was associated with reduced type 2 diabetes risk in low PM_(2.5) stratification (≤65.02 μg/m^(3)) other than in high PM_(2.5) stratification (>65.02 μg/m^(3)), with the hazard ratio (HR) of 0.75 (95% confidence interval [CI]: 0.66-0.85) and 1.10 (95% CI: 0.99-1.22), respectively. Similar results were observed for PA intensity. High PM_(2.5) exposure combined with the highest PA levels increased the risk of type 2 diabetes the most (HR= 1.79, 95% CI: 1.59-2.01 for PA volume;HR = 1.82, 95% CI: 1.64-2.02 for PA intensity).Conclusion: PA could reduce type 2 diabetes risk in low-pollution areas, but high PM_(2.5) exposure may weaken or even reverse the protective effects of PA. Safety and health benefits of PA should be thoroughly assessed for long-term polluted residents.
文摘Objective To evaluate the antagonistic effects of N-acetylcysteine(NAC)on mitogen-activated protein kinases(MAPK)pathway activation,oxidative stress and inflammatory responses in rats with lung injury induced by fine particulate matter(PM2.5).Methods Forty eight male Wistar rats were randomly divided into six groups:blank control group(C1),water drip control group(C2),PM2.5 exposed group(P),low-dose NAC treated and PM2.5 exposed group(L),middle-dose NAC treated and PM2.5 exposed group(M),and high-dose NAC treated and PM2.5 exposed group(H).PM2.5 suspension(7.5 mg/kg)was administered tracheally once a week for four times.NAC of 125 mg/kg,250 mg/kg and 500 mg/kg was delivered intragastrically to L,M and H group respectively by gavage(10 ml/kg)for six days before PM2.5 exposure.The histopathological changes and human mucin 5 subtype AC(MUC5AC)content in lung tissue of rats were evaluated.We investigated IL-6 in serum and bronchoalveolar lavage fluid(BALF)by Enzyme-linked immunosorbent assay(ELISA),MUC5AC in lung tissue homogenate by ELISA,glutathione peroxidase(GSH-PX)in serum and BALF by spectrophotometry,and the expression of p-ERK1/2,p-JNK1/2 and p-p38 proteins by Western blot.All the measurements were analyzed and compared statistically.Results Lung tissue of rats exposed to PM2.5 showed histological destruction and increased mucus secretion of bronchial epithelial cells.Rats receiving NAC treatment showed less histological destruction and mucus secretion.Of P,L,M and H group,MUC5AC in lung tissue,IL-6 in serum and BALF were higher than controls(C1 and C2)(all P<0.05),with the highest levels found in the P group and a decreasing trend with increase of NAC dose.The activity of GSH-PX in serum and BALF of PM2.5 exposed rats(P,L,M and H)was lower than that of controls(all P<0.05),with higher activities found in NAC treated rats(L,M,and H),and an increasing trend with increase of NAC dose.The expressions of p-ERK1/2,p-JNK1/2 and p-p38 proteins in PM2.5 exposed lung tissue(P,L,M and H)was higher than controls(all P<0.05),with decreased levels and dose dependent downregulation found in NAC treated rats.Conclusion NAC can antagonize major MAPK pathway activation,lung oxidative stress and inflammatory injury induced by PM2.5 in rats.
文摘华北大气污染区域化正在对农业生态区域产生显著影响,为了了解华北农业地区大气细颗粒物PM_(2.5)的季节分布特征,2017年7月、9月、12月以及2018年4月在中国科学院禹城农业生态综合实验站进行分季节PM_(2.5)样品采集,并测定分析了样品中31种化学成分。结果表明,碳质气溶胶总体的浓度水平为13.11±8.37μg m^(−3),有机碳(OC)冬春季节浓度较高,元素碳(EC)浓度在秋冬季节较高。同时OC/EC的比值在秋季明显偏低,表明在秋季二次碳质气溶胶对PM_(2.5)贡献较小。水溶性离子浓度总体在冬季最高。NO_(3)^(-)/SO_(4)^(2-)比值在夏季明显偏低为0.69,华北地区夏季固定点源对大气污染的贡献相对较高。PM_(2.5)中金属元素以Na、Mg、Al、Ca、K、Fe等地壳元素为主,具有致癌风险的Co、Cr、Ni、Pb、As等金属元素年均浓度为0.32±0.24 ng m^(−3)、5.40±5.42 ng m^(−3)、10.23±7.46 ng m^(−3)、42.23±27.75 ng m^(−3)、5.66±3.79 ng m^(−3)。受体模型(PMF)计算结果表明,PM_(2.5)的主要来源为二次污染源、生物质燃烧源、燃煤燃油源、柴油车尾气和土壤源,贡献率分别达37.1%、18.2%、14.2%、9.4%和7.9%,表明农业区细颗粒物污染受到华北工业、农业与自然排放的多重影响。
文摘The aim of present research is to study the dispersion of air pollutants using the air quality model, AERMOD and to predict the impact of pollutants (PM<sub>10</sub>, NO<sub>2</sub> and CO) at the receptor level released from Gas Based Power Plant (GBPP). The net-concentrations including monitored data plus predicted values of PM<sub>10</sub>, NO<sub>2</sub> and CO would be increased from base value 75 to 77.61 μg/m<sup>3</sup> with an increase of 3.48%, 22 to 26.66 μg/m<sup>3</sup> with an increase of 21.18% and 428 to 538.37 μg/m<sup>3</sup> with an increase of 25.79% respectively. The study of hill effect showed that it had profound impact upon the dispersion of pollutants and the ratio (with hill and without hill) of each pollutant was 3.89 for PM<sub>10</sub> (24 hr), 2.40 for NO<sub>2</sub> (24 hr) and 13.98 for CO (1 hr). The natural gas based plant not only decreases the pollution level but also reduces the hospital treatment cost and protects the public health. The modeling results suggest that the GBPP could be a clean technology as replacement of coal power plants located in the city which pollute the environment considerably in spite of control measures installed.
基金the Electively Sponsored Project for Scientific Research of Returnees After Study Abroad.
文摘Objective To verify whether Warthin-Starry (WS) silver method could detect the air particulate matter (PM)/dust particles (Ps) located within the macrophages in situ. Methods There were 26 autopsy cases that resulted from cerebral hemorrhage (group A), silicosis (group B), and fetal death during pregnancy (group C). Samples were collected separately and serial sections were prepared from the lungs and lymph nodes and stained with hematoxylin and eosin (HE), WS silver, immunohistochemistry of CD68. Furthermore, ultrathin sections were taken from the WS positive serial sections of groups A and B. Ps were observed under a transmission electron microscope (TEM) and the elements of Ps were measured by X-ray spectrum analysis (X-RSA). Results In both groups A and B, WS staining was positive for the larger and fine Ps, the so called "dust cells", but HE staining was almost negative for fine Ps. In group C, no larger or fine Ps were found. Immunohistochemical staining of CD68 certified that the "dust cells" containing Ps were macrophages. The results of TEM and X-RSA proved that the structure and elements of Ps belonged to PM indeed. Conclusion WS staining is a better than HE staining in showing the location of PM within macrophages.
基金supported by the Pilot Project of the Knowledge Innovation Program of the Chinese Academy of Sciences(Grant No.KZCX2-YW-Q11-03)the Research and Development Special Fund for Public Welfare Industry(Meteorology) of the China Meteorological Administration(Grant No. GYHY201006047)+2 种基金the Special Scientific Research Funds for Environment Protection Commonweal Section(Grant No.200809143)the Innovation Method Fund of China(Grant No.2008IM020500)the Ministry of Science and Technology of China(Grant No. 2010DFA22770)
文摘To investigate aerosol optical properties in the Beijing metropolitan area, aerosol absorption coefficient (Ab), scattering coefficient (So), and fine particulate matter (PM2.5) were measured in the Beijing urban area from 20 May to 30 August 2009. The average Ab, So, single scat- tering albedo (SSA), and PM2.5 concentration were 58.0±39.5 M m^-1, 343.5±353.7 M m 1, 0.80±0.10 and 63.6+50.0 μg m^-3, respectively, during the observation period. Ab, Sc, and SSA all showed single peak diurnal variations, with their maximum values being measured at 0500, 1000, and 1300 local time, respectively. Ab and Sc had a strong positive correlation with PM2.5, and Ab, Sc, and PM25 all had positive correlations with relative humidity and negative correlations with wind speed.
基金supported by the Natural Science Foundations of China[21777100]
文摘Objective Fine particulate matter(PM^(2.5))is an air pollutant that has become of great concern in recent years.Numerous studies have found that PM^(2.5)may contribute to lung cancer,but the pathogenesis has not yet been fully elucidated.In this study,we explored the roles of exosomes from bronchial epithelial cells in PM^(2.5)-promoted lung cancer metastasis.Methods Exosomes were isolated from cell supernatants.An animal model of lung metastasis(established by tail vein injection of A549-luc)and in vitro studies with lung cancer cell lines were used to investigate the effects of exosomes derived from PM^(2.5)-treated human bronchial epithelial cells(PHBE-exo).Results The animal experiments revealed that PHBE-exo-treated mice showed stronger luciferase activity and a larger relative metastatic region in the lungs,thus indicating that PHBE-exo promoted the metastatic potential of lung cancer.Additionally,PHBE-exo promoted the migration,invasion and epithelial-to-mesenchymal transition of lung cancer cells,in a manner mediated by activation of c-Jun Nterminal kinase.Conclusion These results implied that PM^(2.5)may promote the development of lung cancer through exosomes derived from bronchial epithelial cells,thus providing a potential interventional target for lung cancer.These findings broadened our understanding of cancer-promoting mechanisms of environmental pollutants.
基金supported by grants from the National Key Research and Development Program of China(No.2016YFC0206500)the National Research Program for Key Issues in Air Pollution Control of China(No.DQGG0401).
文摘In China, the level of ambient fine particulate matter (PM_(2.5)) pollution far exceeds the air quality standards recommended by the World Health Organization. Moreover, the health effects of PM_(2.5) exposure have become a major public health issue. More than half of PM_(2.5)-related excess deaths are caused by cardiopulmonary disease, which has become a major health risk associated with PM_(2.5) pollution. In this review, we discussed the latest epidemiological advances relating to the health effects of PM_(2.5) on cardiopulmonary diseases in China, including studies relating to the effects of PM_(2.5) on mortality, morbidity, and risk factors for cardiovascular and respiratory diseases. These data provided important evidence to highlight the cardiopulmonary risk associated with PM_(2.5) across the world. In the future, further studies need to be carried out to investigate the specific relationship between the constituents and sources of PM_(2.5) and cardiopulmonary disease. These studies provided scientific evidence for precise reduction measurement of pollution sources and public health risks. It is also necessary to identify effective biomarkers and elucidate the biological mechanisms and pathways involved;this may help us to take steps to reduce PM_(2.5) pollution and reduce the incidence of cardiopulmonary disease.
基金funded by the National Key Research and Development Program of China(No.2019YFC0214801)National Natural Science Foundation of China(Nos.92043301 and 92143301)。
文摘This review aimed to systematically summarize the epidemiological literature on the cardiorespiratory effects of PM_(2.5)published during the 13^(th) Five-Year Plan period(2016-2020)in China.Original articles published between January 1,2016 and June 30,2021 were searched in PubMed,Web of Science,the China National Knowledge Internet Database and Wanfang Database.Random-or fixed-effects models were used to pool effect estimates where appropriate.Of 8558 records identified,145 met the full eligibility criteria.A 10μg/m^(3) increase in short-term PM_(2.5)exposure was significantly associated with increases of 0.70%,0.86%,0.38%and 0.96%in cardiovascular mortality,respiratory mortality,cardiovascular morbidity,and respiratory morbidity,respectively.The specific diseases with significant associations included stroke,ischemic heart disease,heart failure,arrhythmia,chronic obstructive pulmonary disease,pneumonia and allergic rhinitis.The pooled estimates per 10μg/m^(3) increase in long-term PM_(2.5)exposure were 15.1%,11.9%and 21.0%increases in cardiovascular,stroke and lung cancer mortality,and 17.4%,11.0%and 4.88%increases in cardiovascular,hypertension and lung cancer incidence respectively.Adverse changes in blood pressure,heart rate variability,systemic infiammation,blood lipids,lung function and airway infiammation were observed for either short-term or long-term PM_(2.5)exposure,or both.Collectively,we summarized representative exposure-response relationships between short-and long-term PM_(2.5)exposure and a wide range of cardiorespiratory outcomes applicable to China.The magnitudes of estimates were generally smaller in short-term associations and comparable in long-term associations compared with those in developed countries.Ourfindings are helpful for future standard revisions and policy formulation.There are still some notable gaps that merit further investigation in China.