Showing papers on "Air pollutant concentrations published in 2008"

A Cohort Study of Traffic-Related Air Pollution Impacts on Birth Outcomes

Abstract: Numerous studies have indicated associations between exposure to ambient air pollution and adverse pregnancy outcomes. Such associations, if determined to be causal, are likely to result in significant public health impacts given the widespread exposure to air pollution and the fact that low birth weight (LBW) or preterm births are subsequently associated with long-term sequelae such as developmental disability and chronic lung disease (Cano et al. 2001; Dik et al. 2004). Determination of a causal relationship between air pollution and adverse pregnancy outcomes would have implications for burden of disease measures and add to the importance of strategies to mitigate the health effects of air pollution exposure. Previous studies have been reviewed in detail. Sram et al. (2005) concluded that evidence is sufficient to support a causal association between ambient concentrations of particulate matter and LBW, but evidence of effects for other pollutants and for other outcomes such as preterm birth is less robust. Maisonet et al. (2004) concluded that studies to date support small effects of air pollution on preterm birth and small for gestational age birth (SGA), but not full-term LBW. In a systematic review, Glinianaia et al. (2004) suggested that evidence of associations with air pollution and fetal growth or pregnancy duration is limited and inconclusive and argued for population-based cohort designs using high-quality individual exposure estimates. These reviews highlight the difficulties in interpreting an evidence base with differences among methods and with important limitations. First, most studies are either time-series studies (Dugandzic et al. 2006; Liu et al. 2003, 2007; Mannes et al. 2005; Sagiv et al. 2005) that relate relatively short-term changes in air pollution concentrations to temporal changes in rates of adverse pregnancy outcomes or, less frequently, cohort analyses that compare outcomes between locations with differing levels of ambient air pollution (Salam et al. 2005) based on interpolated ambient monitoring network data. Between-city comparisons are subject to potential confounding because covariates may be highly correlated with air pollution, whereas time-series studies are problematic to interpret because they relate short-term changes in air pollution that are driven primarily by meteorology to outcomes. They inherently assume that the impact of air pollution on birth outcomes is acute, require knowledge of the relevant periods of pregnancy during which air pollution may have impacts, and are subject to potential confounding by seasonally varying factors. As reviewed by Glinianaia et al. (2004), a number of studies have suggested stronger relationships between birth outcomes and exposure during specific periods of pregnancy based on comparison of statistical effect sizes. However, results across studies have not consistently identified specific periods of exposure that are most closely linked to adverse pregnancy outcomes. Increasingly, air pollution researchers have identified important spatial variability in air pollution concentrations within airsheds (Hoek et al. 2002b; Lewne et al. 2004; Zhang et al. 2004; Zhu et al. 2004). In many situations these contrasts are of greater magnitude than between-city or temporal contrasts (Jerrett et al. 2005). Such spatial contrasts, primarily related to measures of proximity to traffic corridors, have been associated with a number of health impacts including mortality (Hoek et al. 2002a; Maynard et al. 2007; Miller et al. 2007; Nafstad et al. 2004; Roemer and van Wijnen 2001), asthma and respiratory symptoms (Bayer-Oglesby et al. 2006; Brauer et al. 2002, 2007; Gauderman et al. 2005, 2007; McConnell et al. 2006; Ryan et al. 2005; Smargiassi et al. 2006), and otitis media (Brauer et al. 2006). Application of within-airshed spatial contrasts in birth outcome studies are few (Leem et al. 2006; Parker et al. 2005; Ritz and Yu 1999; Ritz et al. 2000; Slama et al. 2007; Wilhelm and Ritz 2003, 2005). These studies, though provocative, have been limited largely to Southern California—a metropolitan area with relatively high levels of ambient air pollution. They relied on interpolated ambient monitoring data or simple road proximity measures rather than high-resolution spatial contrasts in concentrations. We sought to assess the relationship between reproductive outcomes and spatial and temporally varying levels of air pollution in the metropolitan area of Vancouver, British Columbia, Canada, a city with relatively low levels of ambient air pollution. We estimated exposures at the individual level, for a population-based cohort using both monitor-based methods and land use regression models based on proximity to traffic sources, land use, population density, and topographic features. Even in Vancouver, an area with a dense ambient monitoring network, exposure assessment based on regulatory monitoring network data is more suited to characterizing temporal variability. Land use regression models, even those with temporal components, as in this analysis, focus on high-resolution spatial variability in air pollutant concentrations. The literature describing associations between air pollution and birth outcomes has focused on clinically defined outcomes of LBW and preterm birth, defined in a variety of ways, which complicates comparisons. The underlying biological processes—fetal growth restriction and inadequate gestational length—are incompletely understood and imperfectly represented in routinely available perinatal measurements available in vital statistic records. We elected to focus on SGA births as a primary outcome measure, because birth weight as a function of gestational age has a direct effect on perinatal morbidity and mortality (Pollack and Divon 1992). LBW may result from complex and multiple pathways of fetal growth restriction attributed to maternal, fetal, or placental factors. Three broad categories of biological factors have been suggested to play a role in inadequate fetal gestation: abnormality of the biological clock, abnormal implantation, and infection and inflammation (Mattison et al. 2003). The current theories provide multiple sites at which environmental factors may influence biological factors to modulate fetal growth and induce preterm birth. However, specific toxicologic mechanisms including relevant timing during gestational development are not known. We explored each of these processes, fetal growth restriction and inadequate gestational length, separately, and explored the influences of exposure timing in early and late pregnancy.

Update of WHO air quality guidelines

Abstract: Based on a systematic review of literature on adverse health effects of air pollution, the World Health Organization has updated its Air Quality Guidelines in 2005. The current update is intended to be relevant and applicable worldwide and takes into consideration large regional inequalities in exposures to air pollution. It recommends guideline levels for particulate matter, ozone, nitrogen dioxide and sulfur dioxide, as well as the set of interim targets for these pollutants’ concentrations, encouraging gradual improvement of air quality and reduction of health impacts of the pollution.

Acute respiratory health effects of air pollution on children with asthma in US inner cities

Abstract: Background Children with asthma in inner-city communities may be particularly vulnerable to adverse effects of air pollution because of their airways disease and exposure to relatively high levels of motor vehicle emissions. Objective To investigate the association between fluctuations in outdoor air pollution and asthma morbidity among inner-city children with asthma. Methods We analyzed data from 861 children with persistent asthma in 7 US urban communities who performed 2-week periods of twice-daily pulmonary function testing every 6 months for 2 years. Asthma symptom data were collected every 2 months. Daily pollution measurements were obtained from the Aerometric Information Retrieval System. The relationship of lung function and symptoms to fluctuations in pollutant concentrations was examined by using mixed models. Results Almost all pollutant concentrations measured were below the National Ambient Air Quality Standards. In single-pollutant models, higher 5-day average concentrations of NO 2 , sulfur dioxide, and particles smaller than 2.5 μm were associated with significantly lower pulmonary function. Higher pollutant levels were independently associated with reduced lung function in a 3-pollutant model. Higher concentrations of NO 2 and particles smaller than 2.5 μm were associated with asthma-related missed school days, and higher NO 2 concentrations were associated with asthma symptoms. Conclusion Among inner-city children with asthma, short-term increases in air pollutant concentrations below the National Ambient Air Quality Standards were associated with adverse respiratory health effects. The associations with NO 2 suggest that motor vehicle emissions may be causing excess morbidity in this population.

Traffic and Meteorological Impacts on Near-Road Air Quality: Summary of Methods and Trends from the Raleigh Near- Road Study

Abstract: A growing number of epidemiological studies conducted worldwide suggest an increase in the occurrence of adverse health effects in populations living, working, or going to school near major roadways. A study was designed to assess traffic emissions impacts on air quality and particle toxicity near a heavily traveled highway. In an attempt to describe the complex mixture of pollutants and atmospheric transport mechanisms affecting pollutant dispersion in this near-highway environment, several real-time and time-integrated sampling devices measured air quality concentrations at multiple distances and heights from the road. Pollutants analyzed included U.S. Environmental Protection Agency (EPA)-regulated gases, particulate matter (coarse, fine, and ultrafine), and air toxics. Pollutant measurements were synchronized with real-time traffic and meteorological monitoring devices to provide continuous and integrated assessments of the variation of near-road air pollutant concentrations and particle toxicity with changing traffic and environmental conditions, as well as distance from the road. Measurement results demonstrated the temporal and spatial impact of traffic emissions on near-road air quality. The distribution of mobile source emitted gas and particulate pollutants under all wind and traffic conditions indicated a higher proportion of elevated concentrations near the road, suggesting elevated exposures for populations spending significant amounts of time in this microenvironment. Diurnal variations in pollutant concentrations also demonstrated the impact of traffic activity and meteorology on near-road air quality. Time-resolved measurements of multiple pollutants demonstrated that traffic emissions produced a complex mixture of criteria and air toxic pollutants in this microenvironment. These results provide a foundation for future assessments of these data to identify the relationship of traffic activity and meteorology on air quality concentrations and population exposures.

Analysis of air quality monitoring networks by functional clustering

Abstract: SUMMARY Air quality monitoring networks are important tools in management and evaluation of air quality. Classifying monitoring stations via homogeneous clusters allows identification of similarities in pollution, of representative sites, and of spatial patterns. Instead of summaries by statistical indicators, we propose to consider the air pollutant concentrations as functional data. We then classify using functional cluster analysis, where Partitioning Around Medoids (PAM) algorithm is embedded. The proposed data analysis approach is applied to the air quality monitoring network in Piemonte (Northern Italy); we consider the three more critical pollutants: NO2 ,P M 10, and O3. Copyright © 2008 John Wiley & Sons, Ltd.

A new approach to link transport emissions and air quality: An intelligent transport system based on the control of traffic air pollution

Abstract: Road transport has become by far the major source of environmental pollution and traffic congestion in urban areas. Though a lot of research has been done to investigate the functional relationship linking air quality and air pollution from transport, a further improvement in the knowing of this relationship is needed. The aim of this study was to analyze this relationship and to develop a more flexible framework to allow communication between transport emissions and air quality concentrations. This paper describes the development of this framework, suggests methodological tools to mitigate its problems and shows its application to the mega-city of Beijing, in P.R. China. The result of implementing this methodology would be a system providing high time/space resolution measurements of both air pollutant concentrations and traffic emissions data, as well as real-time transportation and dispersion modelling of those data. The key advantage of the system proposed would be the runtime integration of modelling, to interpret the data measured, with measurements, to validate the data modelled. The findings from the case-study of Beijing show that the integrated system can link traffic air pollution measurements through various modelling modules in order to automate transport-related air pollution assessment.

Investigating the impacts of some meteorological parameters on air pollution in Balikesir, Turkey.

Abstract: Air pollution is one of the most important environmental problems in Balikesir, situated in the western part of Turkey, during the winter periods. The unfavorable climate as well as the city's topography, and inappropriate fuel usage cause serious air pollution problems. The air pollutant concentrations in the city have a close relationship with meteorological parameters. In the present study, the relationship between daily average total suspended particulate (TSP) and sulphur dioxide (SO2) concentrations measured between 1999--2005 winter seasons were correlated with meteorological factors, such as wind speed, temperature, relative humidity and pressure. This statistical analysis was achieved using the stepwise multiple linear regression method. According to the results obtained through the analysis, higher TSP and SO2 concentrations are strongly related to colder temperatures, lower wind speed, higher atmospheric pressure and higher relative humidity. The statistical models of SO2 and TSP gave correlation coefficient values (R2) of 0.735 and 0.656, respectively.

Measurements of Ultrafine Particles and Other Vehicular Pollutants inside a Mobile Exposure System on Los Angeles Freeways

Abstract: A mobile exposure and air pollution measurement system was developed and used for on-freeway ultrafine particle health effects studies. A nine-passenger van was modified with a high-efficiency particulate air (HEPA) filtration system that can deliver filtered or unfiltered air to an exposure chamber inside the van. State-of-the-art instruments were used to measure concentration and size distribution of fine and ultrafine particles and the concentration of carbon monoxide (CO), black carbon (BC), particle-bound polycyclic aromatic hydrocarbons (PAHs), fine particulate matter (PM2.5) mass, and oxides of nitrogen (NOx) inside the exposure chamber. This paper presents the construction and technical details of the van and air pollutant concentrations collected in 32 2-hr runs on two major Los Angeles freeways, Interstate 405 (I-405; mostly gasoline traffic) and Interstate 710 (I-710; large proportion of heavy-duty diesel traffic). More than 97% of particles were removed when the flow through the filte...

Identification of risk factors for sub-optimal housing conditions in Australian piggeries: Part 1. Study justification and design.

Abstract: We undertook a literature search related to pig production facilities with two major aims: first, to review all the likely benefits that might be gained from air quality improvements; and second, to review previous research that had identified statistically significant factors affecting airborne pollutants and environmental parameters, so that these factors could be considered in a multifactorial analysis aimed at explaining variations in air pollutant concentrations Ammonia, carbon dioxide, viable bacteria, endotoxins, and inhalable and respirable particles were identified as major airborne pollutants in the review We found that high concentrations of airborne pollutants in livestock buildings could increase occupational health and safety risks, compromise the health, welfare, and production efficiency of animals, and affect the environment Therefore, improving air quality could reduce environmental damage and improve animal and worker health To achieve a reduction in pollutant concentrations, a better understanding of the factors influencing airborne pollutant concentrations in piggery buildings is required Most of the work done previously has used simple correlation matrices to identify relationships between key factors and pollutant concentrations, without taking into consideration multifactorial effects simultaneously in a model However, our review of this prior knowledge was the first important step toward developing a more inclusive statistical model This review identified a number of candidate risk factors, which we then took into consideration during the development of multifactorial statistical models We used a general linear model (GLM) to model measured internal concentrations, emissions, and environmental parameters in order to predict and potentially control the building environment

Evaluation of relationship between meteorological parameters and air pollutant concentrations during winter season in Elazığ, Turkey

Abstract: In recent years, due to the rapid increase in population density, building density and energy consumption, the outdoor air quality has deteriorated in the crowded urban areas of Turkey. Elazig city, which is located in the east Anatolia region of Turkey, is also influenced by air pollutants. In the present study, relationship between monitored air pollutant concentrations such as SO2 and the total suspended particles (TSP) data and meteorological factors such as wind speed, temperature, relative humidity, solar radiation and atmospheric pressure was investigated in months of October, November, December, January, February, and March during the period of 3 years (2003, 2004 and 2005) for Elazig city. According to the results of linear and non-linear regression analysis, it was found that there is a moderate and weak level of relation between the air pollutant concentrations and the meteorological factors in Elazig city. The correlation between the previous day’s SO2, TSP concentrations and actual concentrations of these pollutants on that day was investigated and the coefficient of determination R2 was found to be 0.64 and 0.54, respectively. The statistical models of SO2 and TSP including all of meteorological parameters gave R2 of 0.20 and 0.12, respectively. Further, in order to develop this model, previous day’s SO2 and TSP concentrations were added to the equations. The new model for SO2 and TSP was improved considerably with R2 = 0.74 and 0.61, respectively.

Outdoor Air Pollution: Sources, Atmospheric Transport, and Human Health Effects

Abstract: In this article, we discuss each of the major indoor and outdoor air pollutants, how these air pollutants are dispersed in the environment, and what human health effects have been associated with either short-term or long-term exposures to these air pollutants. The focus of the article is on human-derived anthropogenic emissions of air pollution (e.g., from fossil fuel combustion), rather than those from natural causes (e.g., pollens).

Applicability of Air pollution Modeling in a Cluster of Brickfields in Bangladesh

Abstract: Air pollution is one of the major environmental problems now days, especially for developing countries such as Bangladesh and Brickfields have been identified as a vital pollutant source of the major cities of the country. Verification of the applicability of an effective air quality model in Bangladesh condition, especially for brickfield pollution was the main concern of this work. To achieve that objective, ambient pollutant concentrations were measured experimentally and compared with the results generated through modeling using Industrial Source Complex (ISC3) model. Air sampling was done at different locations in a cluster of brickfields of 41 brick kilns near Amin Bazar, Savar using Gastec tubes and High volume sampler. Gastec tubes were used for gaseous pollutants and High volume sampler was used for Total Suspended Particulates (TSP). Gaseous pollutants included Sulfur dioxide, Carbon monoxide, and Hydrocarbons. Those pollutant data at different locations on different days were compared with simulated value generated through ISC3. Industrial Source Complex (ISC3) model was found very effective and appropriate both for gaseous pollutants and particulate matter for brickfield pollution in Bangladesh and which indicates the prospect of utilizing this model for different condition and purposes in Bangladesh. From both the experimental and simulated data, particulate matter had been identified as the most important pollutant in that region which is urgently needed to be taken care of.

Design of an Air-Quality Surveillance System for Buenos Aires City Integrated by a NO x Monitoring Network and Atmospheric Dispersion Models

Abstract: This paper presents an air-quality surveillance system designed to detect the occurrence of air pollutant concentrations greater than a reference level in an urban area. The system is integrated by an air-quality monitoring network and atmospheric dispersion models simulations. An objective methodology to design an urban air-quality monitoring network is proposed. This methodology is based on the analysis of air-quality modelling results. The procedure is applied to design an air-quality monitoring network to control NOx concentration levels in Buenos Aires City. Results indicate that six monitors will detect the occurrence of concentration greater than the air-quality guidelines with an efficiency of about 67%. Once a violation is detected, results of atmospheric dispersion models will help in the determination of affected areas. Four possible examples are included to illustrate the assistance that the results of atmospheric dispersion models can bring to a better estimation of possible affected areas in the city. Combining these results with the last census data, an estimation of the inhabitants possibly exposed is obtained.

Effects of sea-land breezes on the spatial and temporal distribution of gaseous air pollutants at the coastal region of southern taiwan

Abstract: This study investigated the effects of sea-land breezes on the spatial distribution and temporal variation of gaseous air pollutants in the atmosphere around the coastal region of Southern Taiwan Ambient air pollutants were simultaneously monitored both inland and offshore in two intensive monitoring periods Inland monitoring was conducted at two sites associated with fourteen national air quality monitoring stations, while offshore monitoring was conducted at two sites both in an island and on the boat An ambient air quality monitoring protocol was conducted for consecutive 48 h for measurements of air pollutants including O3, SO2, CO, NOX, and THC Data obtained from both inland and offshore monitoring sites were applied to plot the concentration contour of gaseous air pollutants with a software SURFER Hourly variation of air pollutant concentrations was further used to investigate the influences of sea-land breezes on the transportation of gaseous air pollutants around the coastal region of Southern Taiwan Field measurement results showed that ambient air pollutants could be transported back and forth across the coastline Particularly, high concentration of O3 was observed at the far inland sites in the daytime due to sea breeze, while high concentration of O3 was also detected over the sea at the nighttime due to land breeze It suggests that the accumulation of O3 due to sea-land breezes does exist and cannot be ignored in the coastal region of Southern Taiwan

Atmospheric influences and local variability of air pollution close to a motorway in an Alpine valley during winter

Abstract: Air quality is mainly determined by traffic, industrial and urban emissions as well as by specific meteorological and topographic conditions. Focussing on nitrogen oxides and particulate matter, the temporal and spatial differences in air pollution in a deep Alpine valley with a major motorway were studied by a measurement campaign between November 2005 and February 2006 near Schwaz, Austria. The variation of air pollutant concentrations near the motorway was determined on the basis of path-averaged (DOAS) and in situ measurements. The layering of the valley atmosphere and the mixing-layer height were observed continuously by SODAR and ceilometer measurements. The winter-time weather conditions were characterized by exceptionally low temperature and high amount of snow in the valley. This resulted in the development of very stable cold pools with low wind speeds and an accordingly high air pollution burden. During several periods the air pollutants accumulated from day to day and frequent exceedances of NO 2 and PM 10 thresholds were detected. Furthermore it could be concluded that the emission situation was not unusually high during these periods, at least concerning road traffic as the dominant source for nitrogen oxides. Analysis confirmed that the typical weather phenomena associated with stable high-pressure regimes were the main factor for the observed pollution burden. During foehn and cold front passages, which interrupted these high pressure periods, concentration levels generally decreased at the valley ground and increased at the slope. Analysis revealed that this is a consequence of vertical mixing due to the influence of mountain specific wind systems, like thermally driven and quasi-periodic valley or slope winds. NO 2 concentration levels are a matter of concern regarding annual mean values as well as - previously not recorded - exceedances of the half-hourly threshold in severe winter conditions. Compared to previous investigations an increased NO 2 /NO 2 ratio was observed during the measurement campaign which is related to enhanced N0 2 emissions from road traffic in consequence to fleet composition and emission changes.

Transportation and Air Quality

Abstract: This chapter describes how transportation activities have a direct impact on the quality of ambient air. The proper phrase to describe the science that studies this impact is “transportation and air quality” rather than “transportation and air pollution.” For a majority of the substances that may be considered as air pollutants are, in fact, naturally present in the atmospheres. The predominant effect transportation sources have on the atmospheric air is to affect the quality of the ambient air. This chapter presents a broad outline of the underlying science and practices related to transportation air quality.

Air quality impacts of distributed energy resources implemented in the northeastern United States.

Abstract: Emissions from the potential installation of distributed energy resources (DER) in the place of current utility-scale power generators have been introduced into an emissions inventory of the northeastern United States. A methodology for predicting future market penetration of DER that considers economics and emission factors was used to estimate the most likely implementation of DER. The methodology results in spatially and temporally resolved emission profiles of criteria pollutants that are subsequently introduced into a detailed atmospheric chemistry and transport model of the region. The DER technology determined by the methodology includes 62% reciprocating engines, 34% gas turbines, and 4% fuel cells and other emerging technologies. The introduction of DER leads to retirement of 2625 MW of existing power plants for which emissions are removed from the inventory. The air quality model predicts maximum differences in air pollutant concentrations that are located downwind from the central power plants that were removed from the domain. Maximum decreases in hourly peak ozone concentrations due to DER use are 10 ppb and are located over the state of New Jersey. Maximum decreases in 24-hr average fine particulate matter (PM2.5) concentrations reach 3 microg/m3 and are located off the coast of New Jersey and New York. The main contribution to decreased PM2.5 is the reduction of sulfate levels due to significant reductions in direct emissions of sulfur oxides (SO(x)) from the DER compared with the central power plants removed. The scenario presented here represents an accelerated DER penetration case with aggressive emission reductions due to removal of highly emitting power plants. Such scenario provides an upper bound for air quality benefits of DER implementation scenarios.

Air quality management in Mexico.

Abstract: Several significant program and policy measures have been implemented in Mexico over the past 15 yr to improve air quality. This article provides an overview of air quality management strategies in Mexico, including (1) policy initiatives such as vehicle use restrictions, air quality standards, vehicle emissions, and fuel quality standards, and (2) supporting programs including establishment of a national emission inventory, an air pollution episodes program, and the implementation of exposure and health effects studies. Trends in air pollution episodes and ambient air pollutant concentrations are described.

Air pollution is a global problem with local solutions

Abstract: VIEWPOINT | Mario Molina Air pollution is a global problem with local solutions Air pollution is a serious problem in cities across the developing world. Th ere are, however, examples of cities that have taken advantage of existing technologies to partially mitigate the problem. With 20 million people, Mexico City is the world’s second largest city aft er Tokyo. It is also situated in a valley where polluted air tends to become trapped. As a result, it has long suff ered from pollution problems that have adversely aff ected public health. Mexico City’s health problems became so acute in the 1990s that they prompted the government to take action. Emission standards were set and vehicles were required to undergo inspections twice a year. In addition, new vehicles had to be equipped with catalytic converters that signifi cantly reduce noxious tail-pipe emissions. Leaded fuel damages catalytic converters; so, the introduction of catalytic converters also led to the widespread use of lead-free gasoline. Motor vehicles produce three-quarters of Mexico City’s air pollution. As a result, the measures taken have created noticeable improvements in air quality. In China, where large cities also suff er from excessive air pollution, the situation is diff erent. A larger portion of the air pollution is due to emissions from power plants and industrial facilities. Technologies also exist to curb emissions from these sources; however, power plants and industrial facilities drive economic growth in China, where, for example, one new coal-fi red steam plant is being added to the electric grid every 7–10 days. Th e Chinese government made an enormous eff ort to improve air quality in Beijing for the Olympics. We can only hope that this eff ort will spread to other cities as well.

Estimation of Vehicle Toxic Air Pollutant Emissions in China

Abstract: Studying the environmental effects of toxic air pollutants is currently very important in the world.One of the main sources of air pollutants is vehicular exhaust emissions.In this study,average annual vehicle miles traveled,emission of toxic air pollutants per year and mass fraction of NMVOC emissions were obtained through data investigations.NMVOC emission factors were calculated based on the COPERT Ⅳ model,and vehicle emission inventories of different regions and vehicles in 2005 were established.The results showed that the total amount of benzene,1,3-butadiene,formaldehyde,acetaldehyde and acrolein emitted by vehicles in China were 31.65×104,7.45×104,13.26×104,5.11×104 and 1.65×104 t,respectively,and most of them were emitted by motorcycles,gasoline PC and diesel HDT.As for the regions,the amounts of toxic air pollutants emitted by vehicles were high in Guangdong,Shandong,Jiangsu,Zhejiang,Hebei and Henan Provinces.

Spatial analysis of long-term exposure to air pollution and cardiorespiratory mortality in Brisbane, Australia

Abstract: Air pollution is ranked by the World Health Organisation as one of the top ten contributors to the global burden of disease and injury. Epidemiological studies have shown that exposure to air pollution is associated with cardiorespiratory diseases. However, most of the previous studies have looked at this issue using air pollution data from a single monitoring site or average values from a few monitoring sites in a city. There is increasing concern that the relationships between air pollution and mortality may vary with geographical area, particularly for a big city. This thesis consisted of three interlinked studies that aimed to examine the spatial variation in the relationship between long-term exposure to air pollution and cardiorespiratory mortality in Brisbane, Australia. The first study evaluated the long-term air pollution trends in Brisbane, Australia. Air pollution data used in this study were provided by the Queensland Environmental Protection Agency (QEPA). The data comprised the daily average concentrations of particulate matter less then 10 µm in aerodynamic diameter (PM10), nitrogen dioxide (NO2), ozone (O3) and sulphur dioxide (SO2) between 1 January 1980 and 31 December 2004 in two monitoring sites (i.e. Eagle farm and Rocklea), and in other available monitoring sites between 1 January 1996 and 31 December 2004. Computerised data files of daily mortality between 1 January 1996 and 31 December 2004 in Brisbane city were provided by the Office of Economic and Statistical Research of the Queensland Treasury. Population data and the Socio-Economic Indexes for Areas (SEIFA) data in 2001 were obtained from the Australian Bureau of Statistics (ABS) for each statistical local area (SLA) of the Brisbane city. The long-term air pollution (the daily maximum 1-hour average or daily 24-hour average concentrations of NO2, O3 and PM10) trends were evaluated using a polynomial regression model in two monitoring sites (Eagle Farm and Rocklea) in Brisbane, Australia, between 1980 and 2003. The study found that there were significant up-and-down features for air pollution concentrations in both monitoring sites in Brisbane. Rocklea recorded a substantially higher number of days with concentrations above the relevant daily maximum 1-hour or 24-hour standards than that in Eagle Farm. Additionally, there was a significant spatial variation in air pollution concentrations between these areas. Therefore, the results indicated a need to examine the spatial variation in the relationship between long-term exposure to air pollution and cardiorespiratory mortality in Brisbane. The second study examined the spatial variation of SO2 concentrations and cardiorespiratory mortality in Brisbane between 1999 and 2001. Air pollutant concentrations were estimated using geographical information systems (GIS) techniques at a SLA level. Spatial distribution analysis and a multivariable logistic regression model were employed to investigate the impact of gaseous air pollution on cardiorespiratory mortality after adjusting for potential confounding effects of age, sex, calendar year and SEIFA. The results of this study indicate that for every 1 ppb increase in annual average SO2 concentration, there was an estimated increase of 4.4 % (95 % confidence interval (CI): 1.4 - 7.6 %) and 4.8 % (95 % CI: 2.0 - 7.7 %) in cardiovascular and cardiorespiratory mortality, respectively. We estimated that the excess number of cardiorespiratory deaths attributable to SO2 was 312 (3.4% of total cardiorespiratory deaths) in Brisbane during the study period. Our results suggest that long-term exposure to SO2, even at low levels, is a significant hazard to population health. The final study examined the association of long-term exposure to gaseous air pollution (including NO2, O3 and SO2) with cardiorespiratory mortality in Brisbane, Australia, 1996 - 2004. The pollutant concentrations were estimated using GIS techniques at a SLA level. Logistic regression was used to investigate the impact of NO2, O3 and SO2 on cardiorespiratory mortality after adjusting for potential confounding effects of age, sex, calendar year and SEIFA. The study found that there was an estimated 3.1% (95% CI: 0.4 - 5.8%) and 0.5% (95% CI: -0.03 - 1.3 %) increase in cardiorespiratory mortality for 1 ppb increment in annual average concentration of SO2 and O3, respectively. However there was no significant relationship between NO2 and cardiorespiratory mortality observed in the multiple gaseous pollutants model. The results also indicated that long-term exposure to gaseous air pollutants in Brisbane, even at the levels lower than most cities in the world (especially SO2), were associated with cardiorespiratory mortality. Therefore, spatial patterns of gaseous air pollutants and their impact on health outcomes need to be assessed for an evaluation of long-term effects of air pollution on population health in metropolitan areas. This study examined the relationship between air pollution and health outcomes. GIS and relevant mapping technologies were used to display the spatial patterns of air pollution and cardiorespiratory mortality at a SLA level. The results of this study show that long-term exposure to gaseous air pollution was associated with cardiorespiratory mortality in Brisbane and this association appeared to vary with geographic area. These findings may have important public health implications in the control and prevention of air pollution-related health effects, since now many countries and governments have paid more attention to control wide spread air pollution and to protect our environment and human health.

Long Term Analysis of PM 10 Concentration in Seoul Using KZ Filter

Abstract: Local meteorological conditions exert a strong influence over day-to-day variations in air pollutant concentrations. Therefore, the meteorological fluctuations have to be removed in order for air quality planners and managers to examine underlying emissions-related trends and make better air quality management decisions for future. In this study, the meteorologically adjusted trends in Seoul are investigated over the period using Kolmogorov-Zurbenco (KZ) filter. The result indicated that meteorologicaJ variability accounts for about 25% of variability. Both the meteorologically adjusted and unadjusted Jong-term daily concentrations had a significant downward trends and the difference between the meteorologically adjusted and unadjusted was small. So it was assumed that in long-term daily changes, localized changes in emissions is more important than the changes caused by meteorological conditions.