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1.
In India, more than a billion population is at risk of exposure to ambient fine particulate matter (PM2.5) concentration exceeding World Health Organization air quality guideline, posing a serious threat to health. Cause-specific premature death from ambient PM2.5 exposure is poorly known for India. Here we develop a non-linear power law (NLP) function to estimate the relative risk associated with ambient PM2.5 exposure using satellite-based PM2.5 concentration (2001  2010) that is bias-corrected against coincident direct measurements. We show that estimate of annual premature death in India is lower by 14.7% (19.2%) using NLP (integrated exposure risk function, IER) for assumption of uniform baseline mortality across India (as considered in the global burden of disease study) relative to the estimate obtained by adjusting for state-specific baseline mortality using GDP as a proxy. 486,100 (811,000) annual premature death in India is estimated using NLP (IER) risk functions after baseline mortality adjustment. 54.5% of premature death estimated using NLP risk function is attributed to chronic obstructive pulmonary disease (COPD), 24.0% to ischemic heart disease (IHD), 18.5% to stroke and the remaining 3.0% to lung cancer (LC). 44,900 (5900–173,300) less premature death is expected annually, if India achieves its present annual air quality target of 40 μg m 3. Our results identify the worst affected districts in terms of ambient PM2.5 exposure and resulting annual premature death and call for initiation of long-term measures through a systematic framework of pollution and health data archive.  相似文献   

2.
Ground level air pollution, especially fine particulate matter (PM2.5), has been associated with a number of adverse health effects. The dispersion of PM2.5 through the atmosphere depends on several mutually connected anthropogenic, geophysical and meteorological parameters, all of which are affected by climate change. This study examines how projected climate change would affect population exposure to PM2.5 air pollution in Poland. Population exposure to PM2.5 in Poland was estimated for three decades: the 1990s, 2040s and 2090s. Future climate conditions were projected by Regional Climate Model RegCM (Beta), forced by the general atmospheric circulation model ECHAM5. The dispersion of PM2.5 was simulated with chemical transport model CAMx version 4.40. Population exposure estimates of PM2.5 were 18.3, 17.2 and 17.1 μg/m3 for the 1990s, 2040s and 2090s, respectively. PM2.5 air pollution was estimated to cause approximately 39,800 premature deaths in the population of Poland in the year 2000. Our results indicate that in Poland, climate change may reduce the levels of exposure to anthropogenic particulate air pollution in future decades and that this reduction will reduce adverse health effects caused by the air pollution.  相似文献   

3.
BackgroundThe concentrations of ozone (O3) in China are increasing, especially in East China, but its future trends and potential health impacts remain to be explored.ObjectivesThe objective was to assess future trends in O3 concentrations and related premature death in East China between 2005 and 2030.MethodsFirst, a global chemical transport model (MIROC-ESM-CHEM) and regional chemical transport modelling system (including the Weather Research and Forecasting model and the Community Multiscale Air Quality model) were combined to estimate daily O3 concentrations in 2005 and 2030 in East China under the “current legislation” (CLE) and “maximum technically feasible reduction” (MFR) scenarios which were applied globally. O3 concentrations were then linked with population projections, mortality projections, and O3-mortality associations to estimate changes in O3-related mortality in East China.ResultsThe annual mean O3 concentration was projected to increase in East China between 2005 and 2030 under the CLE scenario, while decrease under the MFR scenario. Under the CLE scenario, O3-attributable health burden could increase by at least 40,000 premature deaths in East China, without considering the population growth. Under the MFR scenario, the health burden could decrease by up to 260,000 premature deaths as a result of the reduction in O3 concentration with a static population. However, when the population growth was considered, O3-attributable health burden could increase by up to 46,000 premature deaths in East China under the MFR scenario.ConclusionsThe results suggest that the health burden attributable to O3 may increase in East China in 2030.  相似文献   

4.
We estimated PM2.5-related public health impacts/ton emitted of primary PM2.5, SO2, and NOx for a set of power plants in the Mid-Atlantic and Lower Great Lakes regions of the United States, selected to include varying emission profiles and broad geographic representation. We then developed a regression model explaining variability in impacts per ton emitted using the population distributions around each plant. We linked outputs from the Community Multiscale Air Quality (CMAQ) model v 4.7.1 with census data and concentration–response functions for PM2.5-related mortality, and monetized health estimates using the value-of-statistical-life. The median impacts for the final set of plants were $130,000/ton for primary PM2.5 (range: $22,000–230,000), $28,000/ton for SO2 (range: $19,000–33,000), and $16,000/ton for NOx (range: $7100–26,000). Impacts of NOx were a median of 34% (range: 20%–75%) from ammonium nitrate and 66% (range: 25%–79%) from ammonium sulfate. The latter pathway is likely from NOx enhancing atmospheric oxidative capacity and amplifying sulfate formation, and is often excluded. Our regression models explained most of the variation in impact/ton estimates using basic population covariates, and can aid in estimating impacts averted from interventions such as pollution controls, alternative energy installations, or demand-side management.  相似文献   

5.
Few studies have explored the relationship between coarse particles (PM10-2.5) and adverse birth outcomes. We examined associations between gestational exposure of PM10-2.5 and birth weight. U.S. birth certificates data (1999–2007) were acquired for 8,017,865 births. Gestational and trimester exposures of PM10-2.5 were estimated using co-located PM10 and PM2.5 monitors  35 km from the population-weighted centroid of mothers' residential counties. A linear regression model was applied, adjusted by potential confounders. As sensitivity analyses, we explored alternative PM10-2.5 estimations, adjustment for PM2.5, and stratification by regions. Gestational exposure to PM10-2.5 was associated with 6.6 g (95% Confidence Interval: 5.9, 7.2) lower birth weight per interquartile range increase (7.8 μg/m3) in PM10-2.5 exposures. All three trimesters showed associations. Under different exposure methods for PM10-2.5, associations remained consistent but with different magnitudes. Results were robust after adjusting for PM2.5, and regional analyses showed associations in all four regions with larger estimates in the South. Our results suggest that PM10-2.5 is associated with birth weight in addition to PM2.5. Regional heterogeneity may reflect differences in population, measurement error, region-specific emission pattern, or different chemical composition within PM10-2.5. Most countries do not set health-based standards for PM10-2.5, but our findings indicate potentially important health effects of PM10-2.5.  相似文献   

6.
Satellite-based remote sensing provides a unique opportunity to monitor air quality from space at global, continental, national and regional scales. Most current research focused on developing empirical models using ground measurements of the ambient particulate. However, the application of satellite-based exposure assessment in environmental health is still limited, especially for acute effects, because the development of satellite PM2.5 model depends on the availability of ground measurements. We tested the hypothesis that MODIS AOD (aerosol optical depth) exposure estimates, obtained from NASA satellites, are directly associated with daily health outcomes. Three independent healthcare databases were used: unscheduled outpatient visits, hospital admissions, and mortality collected in Beijing metropolitan area, China during 2006. We use generalized linear models to compare the short-term effects of air pollution assessed by ground monitoring (PM10) with adjustment of absolute humidity (AH) and AH-calibrated AOD. Across all databases we found that both AH-calibrated AOD and PM10 (adjusted by AH) were consistently associated with elevated daily events on the current day and/or lag days for cardiovascular diseases, ischemic heart diseases, and COPD. The relative risks estimated by AH-calibrated AOD and PM10 (adjusted by AH) were similar. Additionally, compared to ground PM10, we found that AH-calibrated AOD had narrower confidence intervals for all models and was more robust in estimating the current day and lag day effects. Our preliminary findings suggested that, with proper adjustment of meteorological factors, satellite AOD can be used directly to estimate the acute health impacts of ambient particles without prior calibrating to the sparse ground monitoring networks.  相似文献   

7.
Ambient PM2.5 pollution is a substantial threat to public health in global megacities. This paper reviews the PM2.5 pollution of 45 global megacities in 2013, based on mass concentration from official monitoring networks and composition data reported in the literature. The results showed that the five most polluted megacities were Delhi, Cairo, Xi'an, Tianjin and Chengdu, all of which had an annual average concentration of PM2.5 greater than 89 μg/m3. The five cleanest megacities were Miami, Toronto, New York, Madrid and Philadelphia, the annual averages of which were less than 10 μg/m3. Spatial distribution indicated that the highly polluted megacities are concentrated in east-central China and the Indo-Gangetic Plain. Organic matter and SNA (sum of sulfate, nitrate and ammonium) contributed 30% and 36%, respectively, of the average PM2.5 mass for all megacities. Notable seasonal variation of PM2.5 polluted days was observed, especially for the polluted megacities of China and India, resulting in frequent heavy pollution episodes occurring during more polluted seasons such as winter. Marked differences in PM2.5 pollution between developing and developed megacities require more effort on local emissions reduction as well as global cooperation to address the PM2.5 pollution of those megacities mainly in Asia.  相似文献   

8.
In the second half of 1997, large areas in Southeast Asia were severely affected by a smoke-haze pollution episode caused by the emissions of an estimated 45,600 km2 of vegetation that burnt on the Indonesian islands Kalimantan and Sumatra. To document the impacts of these fires on air quality, data for total suspended particulate matter (TSP) and for particulate matter below or equal to 10 microns in diameter (PM10) from selected sites in Indonesia, Malaysia and Singapore are analysed in this paper. These data are supplemented by meteorological data, satellite images and a summary of related research. TSP was above 2,000 μg m–3 for several days in Indonesian locations close to the most extensive fire activity. In Malaysia and Singapore, ambient particle concentrations increased to several times their average September levels. Characteristically for emissions from vegetation burning, the additional atmospheric particle loading during the smoke-haze episode was predominantly due to an increase of the fraction below or equal to 2.5 microns in diameter (PM2.5). Due to the dominance of respirable particles (PM2.5) in the smoke-haze, air quality reporting based on TSP or PM10 may be inadequate to assess the health risk. Upgrading of PM2.5 monitoring facilities is therefore needed. Reducing the probability of similar smoke-haze events in future would require appropriate fire use and smoke management strategies. Electronic Publication  相似文献   

9.
Abstract

The Clean Development Mechanism, a flexibility mechanism contained in the Kyoto Protocol, offers China an important tool to attract investment in clean energy technology and processes into its electricity sector. The Chinese electricity sector places centrally in the country's economy and environment, being a significant contributor to the acid rain and air pollution problems that plague many of China's cities and regions, and therefore a focus of many related energy and environmental policies. China's electricity sector has also been the subject of a number of economic analyses that have showed that it contains the highest potential for clean energy investment through the Clean Development Mechanism of any economic sector in China. This mechanism, through the active participation from investors in more industrialized countries, can help alleviate the environmental problems attributable to electricity generation in China through advancing such technology as wind electricity generation, clean coal technology, high efficient natural gas electricity generation, or utilization of coal mine methane. In this context, the Clean Development Mechanism also compliments a range of environmental and energy policies which are strategizing to encourage the sustainable development of China's economy.  相似文献   

10.
The adverse consequences of particulate matter (PM) on human health have been well documented. Recently, special attention has been given to mineral dust particles, which may be a serious health threat. The main global source of atmospheric mineral dust is the Sahara desert, which produces about half of the annual mineral dust. Sahara dust transport can lead to PM levels that substantially exceed the established limit values. A review was undertaken using the ISI web of knowledge database with the objective to identify all studies presenting results on the potential health impact from Sahara dust particles. The review of the literature shows that the association of fine particles, PM2.5, with total or cause‐specific daily mortality is not significant during Saharan dust intrusions. However, regarding coarser fractions PM10 and PM2.5–10 an explicit answer cannot be given. Some of the published studies state that they increase mortality during Sahara dust days while other studies find no association between mortality and PM10 or PM2.5–10. The main conclusion of this review is that health impact of Saharan dust outbreaks needs to be further explored. Considering the diverse outcomes for PM10 and PM2.5–10, future studies should focus on the chemical characterization and potential toxicity of coarse particles transported from Sahara desert mixed or not with anthropogenic pollutants. The results of this review may be considered to establish the objectives and strategies of a new European directive on ambient air quality. An implication for public policy in Europe is that to protect public health, anthropogenic sources of particulate pollution need to be more rigorously controlled in areas highly impacted by the Sahara dust.  相似文献   

11.
Cooking and heating with coal and biomass is the main source of household air pollution in China and a leading contributor to disease burden. As part of a baseline assessment for a household energy intervention program, we enrolled 205 adult women cooking with biomass fuels in Sichuan, China and measured their 48-h personal exposure to fine particulate matter (PM2.5) and carbon monoxide (CO) in winter and summer. We also measured the indoor 48-h PM2.5 concentrations in their homes and conducted outdoor PM2.5 measurements during 101 (74) days in summer (winter). Indoor concentrations of CO and nitrogen oxides (NO, NO2) were measured over 48-h in a subset of ~ 80 homes. Women's geometric mean 48-h exposure to PM2.5 was 80 μg/m3 (95% CI: 74, 87) in summer and twice as high in winter (169 μg/m3 (95% CI: 150, 190), with similar seasonal trends for indoor PM2.5 concentrations (winter: 252 μg/m3; 95% CI: 215, 295; summer: 101 μg/m3; 95% CI: 91, 112). We found a moderately strong relationship between indoor PM2.5 and CO (r = 0.60, 95% CI: 0.46, 0.72), and a weak correlation between personal PM2.5 and CO (r = 0.41, 95% CI: − 0.02, 0.71). NO2/NO ratios were higher in summer (range: 0.01 to 0.68) than in winter (range: 0 to 0.11), suggesting outdoor formation of NO2 via reaction of NO with ozone is a more important source of NO2 than biomass combustion indoors. The predictors of women's personal exposure to PM2.5 differed by season. In winter, our results show that primary heating with a low-polluting fuel (i.e., electric stove or wood-charcoal) and more frequent kitchen ventilation could reduce personal PM2.5 exposures. In summer, primary use of a gaseous fuel or electricity for cooking and reducing exposure to outdoor PM2.5 would likely have the greatest impacts on personal PM2.5 exposure.  相似文献   

12.
BackgroundMotor vehicle emissions contribute nearly a quarter of the world's energy-related greenhouse gases and cause non-negligible air pollution, primarily in urban areas. Changing people's travel behaviour towards alternative transport is an efficient approach to mitigate harmful environmental impacts caused by a large number of vehicles. Such a strategy also provides an opportunity to gain health co-benefits of improved air quality and enhanced physical activities. This study aimed at quantifying co-benefit effects of alternative transport use in Adelaide, South Australia.MethodWe made projections for a business-as-usual scenario for 2030 with alternative transport scenarios. Separate models including air pollution models and comparative risk assessment health models were developed to link alternative transport scenarios with possible environmental and health benefits.ResultsIn the study region with an estimated population of 1.4 million in 2030, by shifting 40% of vehicle kilometres travelled (VKT) by passenger vehicles to alternative transport, annual average urban PM2.5 would decline by approximately 0.4 μg/m3 compared to business-as-usual, resulting in net health benefits of an estimated 13 deaths/year prevented and 118 disability-adjusted life years (DALYs) prevented per year due to improved air quality. Further health benefits would be obtained from improved physical fitness through active transport (508 deaths/year prevented, 6569 DALYs/year prevented), and changes in traffic injuries (21 deaths and, 960 DALYs prevented).ConclusionAlthough uncertainties remain, our findings suggest that significant environmental and health benefits are possible if alternative transport replaces even a relatively small portion of car trips. The results may provide assistance to various government organisations and relevant service providers and promote collaboration in policy-making, city planning and infrastructure establishment.  相似文献   

13.
BackgroundAir pollution benefits assessments tend to be time and resource intensive. Reduced-form approaches offer computational efficiency, but may introduce uncertainty. Some reduced-form approaches apply simplified air quality models, which may not capture the complex non-linear chemistry governing the formation of certain pollutants such as PM2.5. Other approaches apply the results of sophisticated photochemical modeling, but characterize only a small number of source types in a limited geographic area.MethodsWe apply CAMx source apportionment photochemical modeling, coupled with a PC-based human health benefits software program, to develop a suite of PM2.5 benefit per ton estimates. These per-ton estimates relate emission changes to health impacts and monetized benefits for 17 sectors across the continental U.S., including Electricity Generating Units (EGU), mobile, area and industrial point sources.ResultsThe benefit per ton of reducing directly emitted PM2.5 is about an order of magnitude larger than reducing emissions of PM2.5 precursor emissions. On a per-ton basis, the value of reducing directly emitted PM2.5 and PM2.5 precursors in 2005 ranges between approximately $1300 (2010$) for reducing a ton of NOx from Ocean-Going Vessels to about $450,000 (2010$) for reducing a ton of directly emitted PM2.5 from Iron and Steel facilities. The benefit per ton estimates for 2016 are generally higher than the 2005 estimates. The values estimated here are generally comparable with those generated using photochemical modeling, but larger than those calculated using simplified air quality models.ConclusionsOur approach characterizes well the per-ton benefits of reducing emissions from a broad array of 17 industrial point, EGU and mobile sectors, while our use of photochemical air quality modeling gives us greater confidence that we have accounted for the non-linear chemistry governing PM2.5 formation. The resulting benefit per-ton estimates thus represent a compromise between approaches that may simplify the treatment of PM2.5 air quality formation and those techniques that are based in photochemical modeling but account for only a small number of emission sources.  相似文献   

14.
This study investigates the mortality effect of primary and secondary PM2.5 related to ship exhaust in the Sydney greater metropolitan region of Australia. A detailed inventory of ship exhaust emissions was used to model a) the 2010/11 concentration of ship-related PM2.5 across the region, and b) the reduction in PM2.5 concentration that would occur if ships used distillate fuel with a 0.1% sulfur content at berth or within 300 km of Sydney. The annual loss of life attributable to 2010/11 levels of ship-related PM2.5 and the improvement in survival associated with use of low-sulfur fuel were estimated from the modelled concentrations.In 2010/11, approximately 1.9% of the region-wide annual average population weighted-mean concentration of all natural and human-made PM2.5 was attributable to ship exhaust, and up to 9.4% at suburbs close to ports. An estimated 220 years of life were lost by people who died in 2010/11 as a result of ship exhaust-related exposure (95% CIβ: 140–290, where CIβ is the uncertainty in the concentration-response coefficient only). Use of 0.1% sulfur fuel at berth would reduce the population weighted-mean concentration of PM2.5 related to ship exhaust by 25% and result in a gain of 390 life-years over a twenty year period (95% CIβ: 260–520). Use of 0.1% sulfur fuel within 300 km of Sydney would reduce the concentration by 56% and result in a gain of 920 life-years over twenty years (95% CIβ: 600–1200).Ship exhaust is an important source of human exposure to PM2.5 in the Sydney greater metropolitan region. This assessment supports intervention to reduce ship emissions in the GMR. Local strategies to limit the sulfur content of fuel would reduce exposure and will become increasingly beneficial as the shipping industry expands. A requirement for use of 0.1% sulfur fuel by ships within 300 km of Sydney would provide more than twice the mortality benefit of a requirement for ships to use 0.1% sulfur fuel at berth.  相似文献   

15.
BackgroundShort-term exposure to fine particulate matter (PM2.5) air pollution has been associated with altered DNA methylation in observational studies, but it remains unclear whether this change mediates the effects on cardiovascular biomarkers.ObjectiveTo examine the impact of ambient PM2.5 on gene-specific DNA methylation and its potential mediation in the acute effects of PM2.5 on cardiovascular biomarkers.MethodsWe designed a randomized, double-blind crossover trial using true or sham air purifiers for 48 h among 35 healthy college students in Shanghai, China, in 2014. We measured blood global methylation estimated in long interspersed nucleotide element-1 (LINE‑1) and Alu repetitive elements, methylation in ten specific genes, and ten cardiovascular biomarkers. We used linear mixed-effect models to examine the associations between PM2.5 and methylation. We also performed causal mediation analyses to evaluate the potential mediation of methylation in the associations between PM2.5 and biomarkers.ResultsAir purification increased DNA methylation in repetitive elements and all candidate genes. An IQR increase (64 μg/m3) in PM2.5 was significantly associated with reduction of methylation in LINE-1 (1.44%), one pro-inflammatory gene (CD40LG, 9.13%), two pro-coagulant genes (F3, 15.20%; SERPINE1, 3.69%), and two pro-vasoconstriction genes (ACE, 4.64%; EDN1, 9.74%). There was a significant mediated effect (17.82%, P = 0.03) of PM2.5 on sCD40L protein through CD40LG hypomethylation. Hypomethylation in other candidate genes generally showed positive but non-significant mediation.ConclusionsThis intervention study provided robust human evidence that ambient PM2.5 could induce rapid decreases in DNA methylation and consequently partly mediate its effects on cardiovascular biomarkers.  相似文献   

16.
RationaleExposure to ambient particulate matter (PM) and ozone has been associated with cardiovascular disease (CVD). However, the mechanisms linking PM and ozone exposure to CVD remain poorly understood.ObjectiveThis study explored associations between short-term exposures to PM with a diameter < 2.5 μm (PM2.5) and ozone with plasma metabolite concentrations.Methods and resultsWe used cross-sectional data from a cardiac catheterization cohort at Duke University, North Carolina (NC), USA, accumulated between 2001 and 2007. Amino acids, acylcarnitines, ketones and total non-esterified fatty acid plasma concentrations were determined in fasting samples. Daily concentrations of PM2.5 and ozone were obtained from a Bayesian space-time hierarchical model, matched to each patient's residential address. Ten metabolites were selected for the analysis based on quality criteria and cluster analysis. Associations between metabolites and PM2.5 or ozone were analyzed using linear regression models adjusting for long-term trend and seasonality, calendar effects, meteorological parameters, and participant characteristics.We found delayed associations between PM2.5 or ozone and changes in metabolite levels of the glycine-ornithine-arginine metabolic axis and incomplete fatty acid oxidation associated with mitochondrial dysfunction. The strongest association was seen for an increase of 8.1 μg/m3 in PM2.5 with a lag of one day and decreased mean glycine concentrations (− 2.5% [95% confidence interval: − 3.8%; − 1.2%]).ConclusionsShort-term exposures to ambient PM2.5 and ozone is associated with changes in plasma concentrations of metabolites in a cohort of cardiac catheterization patients. Our findings might help to understand the link between air pollution and cardiovascular disease.  相似文献   

17.
ObjectiveWe used log-linear and log-log exposure-response (E-R) functions to model the association between PM2.5 exposure and non-elective hospitalizations for pneumonia, and estimated the attributable hospital costs by using the effect estimates obtained from both functions.MethodsWe used hospital discharge data on 3519 non-elective pneumonia admissions from UZ Brussels between 2007 and 2012 and we combined a case-crossover design with distributed lag models. The annual averted pneumonia hospitalization costs for a reduction in PM2.5 exposure from the mean (21.4 μg/m3) to the WHO guideline for annual mean PM2.5 (10 μg/m3) were estimated and extrapolated for Belgium.ResultsNon-elective hospitalizations for pneumonia were significantly associated with PM2.5 exposure in both models. Using a log-linear E-R function, the estimated risk reduction for pneumonia hospitalization associated with a decrease in mean PM2.5 exposure to 10 μg/m3 was 4.9%. The corresponding estimate for the log-log model was 10.7%. These estimates translate to an annual pneumonia hospital cost saving in Belgium of €15.5 million and almost €34 million for the log-linear and log-log E-R function, respectively.DiscussionAlthough further research is required to assess the shape of the association between PM2.5 exposure and pneumonia hospitalizations, we demonstrated that estimates for health effects and associated costs heavily depend on the assumed E-R function. These results are important for policy making, as supra-linear E-R associations imply that significant health benefits may still be obtained from additional pollution control measures in areas where PM levels have already been reduced.  相似文献   

18.
This study was performed to investigate the concentration of PM10 and PM2.5 inside trains and platforms on subway lines 1, 2, 4 and 5 in Seoul, KOREA. PM10, PM2.5, carbon dioxide (CO2) and carbon monoxide (CO) were monitored using real-time monitoring instruments in the afternoons (between 13:00 and 16:00). The concentrations of PM10 and PM2.5 inside trains were significantly higher than those measured on platforms and in ambient air reported by the Korea Ministry of Environment (Korea MOE). This study found that PM10 levels inside subway lines 1, 2 and 4 exceeded the Korea indoor air quality (Korea IAQ) standard of 150 μg/m3. The average percentage that exceeded the PM10 standard was 83.3% on line 1, 37.9% on line 2 and 63.1% on line 4, respectively. PM2.5 concentration ranged from 77.7 μg/m3 to 158.2 μg/m3, which were found to be much higher than the ambient air PM2.5 standard promulgated by United States Environmental Protection Agency (US-EPA) (24 h arithmetic mean: 65 μg/m3). The reason for interior PM10 and PM2.5 being higher than those on platforms is due to subway trains in Korea not having mechanical ventilation systems to supply fresh air inside the train. This assumption was supported by the CO2 concentration results monitored in tube of subway that ranged from 1153 ppm to 3377 ppm. The percentage of PM2.5 in PM10 was 86.2% on platforms, 81.7% inside trains, 80.2% underground and 90.2% at ground track. These results indicated that fine particles (PM2.5) accounted for most of PM10 and polluted subway air. GLM statistical analysis indicated that two factors related to monitoring locations (underground and ground or inside trains and on platforms) significantly influence PM10 (p < 0.001, R2 = 0.230) and PM2.5 concentrations (p < 0.001, R2 = 0.172). Correlation analysis indicated that PM10, PM2.5, CO2 and CO were significantly correlated at p < 0.01 although correlation coefficients were different. The highest coefficient was 0.884 for the relationship between PM10 and PM2.5.  相似文献   

19.
China has approximately 5.80 × 106 ha coastal wetlands by 2014, accounting for 10.82% of the total area of natural wetlands. Healthy coastal wetland ecosystems play an important role in guaranteeing the territory ecological security and the sustainable development of coastal zone in China. In this paper, the natural geography and the past and present status of China's coastal wetlands were introduced and the five stages (1950s–1970s, 1980s–1991, 1992–2002, 2003–2010 and 2011–present) of China's coastal wetlands conservation from the foundation of the People's Republic in 1949 to present were distinguished and reviewed. Over the past decades, China has made great efforts in coastal wetland conservation, as signified by the implementation of coastal wetland restoration projects, the construction of coastal wetland nature reserves, the practice of routine ecological monitoring and two national wetland surveys, the promulgation of local wetland conservation statutes and specific regulations, the coordination mechanism to enhance management capacity, the wide development of coastal wetland research and public participation, and the extensive communication to strengthen international cooperation. Nonetheless, six major issues recently emerged in China's coastal wetland conservation are evidently existed, including the increasing threats of pollution and human activities, the increasing adverse effects of threaten factors on ecosystem function, the increasing threats of coastal erosion and sea-level rising, the insufficient funding for coastal wetlands conservation, the imperfect legal and management system for coastal wetlands, and the insufficient education, research and international cooperation. Although the threats and pressures on coastal wetlands conservation are still apparent, the future of China's coastal wetlands looks promising since the Chinese government understands that the sustainable development in coastal zone requires new attitudes, sound policies and concerted efforts at all levels. The major strategies for future improvement of China's coastal wetland conservation include: exploring effective measures in response to major threaten factors; improving the conservation and compensation system for coastal wetlands; strengthening coastal wetland legislation and management; increasing funds for coastal wetland conservation and research; and strengthening coastal wetland education and international cooperation.  相似文献   

20.
Abstract

The health impacts of tobacco consumption are well documented and have gained acceptance worldwide. Today, a substantial, preventable burden of tobacco attributable diseases exists in most countries, though in most of the cases, unknown. Smoking accounts for almost half of the deaths in middle age in some regions. In Uganda, translating findings into policy action is slow and involves several stakeholders. It will continue to require support from tobacco control campaign groups. This paper analyses secondary literature on tobacco smoking and later provides an appropriate medium based communication strategy that can be adopted to counteract the persuasive smoking evil adverts of tobacco companies as well as creating awareness among the population of the health impacts caused by smoking.  相似文献   

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