Showing papers on "Air pollutant concentrations published in 2007"

Using grey system theory to evaluate transportation effects on air quality trends in Japan

Abstract: Japan's Air Pollution Control Law signed in 1968 prescribes the maximum permissible limits of motor vehicle exhausts as well as establishing mechanisms for monitoring air pollution In this paper, the grey relational grade of air pollutants from ambient air pollution and roadside air pollution monitoring stations is used to look at the relationship between air pollution and transportation. The results indicated that the ambient and roadside air quality increased by rose from 1975 to 2004 but less fast than the growth in traffic. Some of this may be attributable to the legislation but there have also been other measures since 1968 that have also contributed.

Air pollution and its control in China

Abstract: The rapid growth of China’s economy has led to severe air pollution characterized by acid rain, severe pollution in cities, and regional air pollution. High concentrations are found for various pollutants such as sulfur dioxides (SO2), nitrogen oxides (NOx), and fine particulates. Great efforts have thus been undertaken for the control of air pollution in the country. This paper discusses the development and application of appropriate technologies for reducing the major pollutants produced by coal and vehicles, and investigates air quality modeling as an important support for policy-making.

Evaluation of the Trend of Air Quality in Taipei, Taiwan from 1994 to 2003

Abstract: The data collected from the five air quality monitoring stations established by the Taiwan Environmental Protection Administration (TEPA) in Taipei City were analyzed to assess the changes in air quality. The analyses reveal that the air quality in Taipei City improved over the last decade from 1994 to 2003, as evidenced by the significant downward trends of the various primary air pollutant concentrations, such as CO, NOX, SO2, and PM10. An air pollution fee was collected by TEPA in 1995, and several air pollution control measures were likewise taken to improve the air quality in Taiwan. However, although the extreme daily maximum O3 concentrations occurred more frequently in earlier years and showed a downward trend, its moderately high concentrations increased annually in recent years. It implied that after the reduction of various primary pollutant concentrations, the effective reduction of O3 pollution still remains an important issue.

An Introduction to Air Pollution - Definitions, Classifications, and History

Abstract: Definitions and classifications used in the study of air pollution are introduced. Also introduced are a brief history of air pollution, its regulation, and trends of its ambient concentrations and emissions.

Statistical behavior of carbon monoxide from vehicular exhausts in urban environments

Abstract: Air pollutant concentrations are essentially random variables and can be well described by statistical distribution models. The statistical distribution models are, therefore, useful tools in predicting the distribution of air pollutant concentrations. The statistical distributional form, fitting to the concentrations data, is based upon several factors, i.e. source types, pollutant types, emission patterns, meteorological conditions, and averaging times [Taylor, J.A., Jakeman, A.J., Simpson, R.W., 1986. Modeling distributions of air pollutant concentrations – I: identification of statistical models. Atmospheric Environment 20 (9), 1781–1789]. The statistical characteristics of dispersion of air pollutants in the atmosphere are represented by successive random dilution process [Ott, W.R., 1995. Environmental Statistics and Data Analysis. Lewis publishers]. This process may, however, differ depending upon the location of pollutant dispersion, i.e. near roadways, at intersections or in street canyons. Further, the distributional form may also differ. Several investigators, in the past, presumed lognormal distribution (LND) for the air quality data. While, a few found other distributional form when carried out the actual data analysis. The present paper develops the statistical distribution model fitting to carbon monoxide (CO) concentrations for the heterogeneous traffic pattern at the urban hotspots in Delhi, India. Three years of 1-h average CO concentration data (from 1997 to 1999), at the traffic intersection and near a roadway, are examined using goodness-of-fit tests for the suitable statistical distributional form. The results showed that the log logistic distribution model (LLD) best fit the CO concentration data at both the intersection and the roadway. It can therefore be deduced that ‘heterogeneity in traffic’ and ‘emission patterns’ may be affecting the statistical distributional form significantly.

Health and air pollution in New Zealand: main report

Abstract: This study is concerned with identifying and quantifying the health risks in New Zealand due to people's exposure to air pollution It aims to explicitly identify the effects of air pollution throughout New Zealand, to link these effects to the various sources of air pollution, and to provide information that will help to formulate effective policy options that lead to real and measurable improvements in the health of New Zealanders (a)

The relationship between outdoor air quality and respiratory symptoms in young children.

Abstract: The aim of this study was to investigate the relationship between air pollution and respiratory symptoms in young children. A total of 263 children at high risk of developing asthma or atopy were recruited antenatally and all respiratory symptoms experienced by the children were recorded by their parents for five years. Daily pollutant concentrations and meteorological data (ambient temperature and humidity) were collected from network monitoring sites. Logistic regression models investigating relationships between individual air pollutants and respiratory symptoms showed significant associations between Ozone (O3) (1 h and 8 h) concentrations and raised body temperature (lag 0); Carbon monoxide (CO) (8 h) and wheeze/rattle and runny/blocked nose (lag 5 and additive exposure over 5 days); Nitrogen dioxide (NO2) (24 h) concentrations and cough (lag 0 and additive exposure over 5 days) and PM2.5 and visibility (BSP) (1 h) with cough (lag 0). These associations were observed even though air pollutant concentrations were below national standards throughout the study period.

Air Pollution and Health

Abstract: The impact of air pollution on human health is currently of international concern. A comprehensive review of the subject is given in this volume, which complements the previous title covering air quality management. Dealing with the common gaseous and particulate air pollutants, including chemical carcinogens, it reviews the epidemiological and exposure chamber study research as well as considering mechanistic studies in the case of particulate matter. The book also addresses the practical issue of setting standards for human exposure to air pollution by including the philosophy of standard setting and a review of currently available standards, along with a description of the setting of US EPA revised standards for ozone and particulate matter. Current knowledge of indoor air pollution is also discussed. Chapter headings are: air quality health issues for Government; gaseous pollutants (SO{sub 2}, NO{sub 2}, CO, O{sub 3}); chemical carcinogens; limitations of epidemiological studies; the 1997 US EPA standards for particulate matter and ozone; health effects of indoor air pollutants; setting health-based air quality standards; and mechanistic aspects of the health effects of airborne particles.

An operational real-time air quality modelling system for industrial plants

Abstract: The advances on computer power capabilities and air quality modelling systems (AQMS) has reached to a high degree of sophistication during the last decade. Nowadays, the state-of-the-art air quality modelling systems such as MM5–CMAQ can handle the evaluation of air pollution concentrations in a very high detail in time and space. MM5 is a non-hydrostatic modelling system developed by PSU/NCAR (USA) during the last 20 years and continuously updated by the scientific community. CMAQ is a Community Multi-scale Air Quality Modelling System for simulating the transport and chemical concentrations in the air in 3D space and time developed by EPA (USA) in 2000. Both systems are complementary and allow a full simulation of the atmospheric flow to determine the amount of air pollution concentration exists in the 3D space and during a specific period of time. TEAP (a tool to evaluate the air quality impact of industrial plants) is an EUREKA project coordinated by UPM with the participation of INDRA S.A., Institute of Physics (Lithuania) and AB ‘MAZEIKIU NAFTA’ (Lithuania). This tool allows the industrial plants – and electric power plants – to have a full control in real-time and forecasting mode of the impact of the industrial emission under daily basis by using the so-called ON–OFF operational mode. The ON–OFF mode requires to run the AQMS both time in parallel by using the industrial plant emissions (ON) and excluding them (OFF). The system allows a full knowledge of the impact of industrial emissions for the next 48–72 h in full space (3D) domain, time and for every criteria pollutant (NOx, SO2, CO, O3, PM). The system requires a powerful post-processing analysis module and a clustering approach to optimize the computer capabilities. The system is mounted over a PC cluster platform under Linux operating system. Results show a full and detail analysis of the amount of air pollutant concentrations due to the industrial plant emissions in time and space and under daily operational basis. The EU Air Quality Directives mark the air concentration limits to be taken into account into the TEAP system in forecasting mode to be fulfilled. The system allows to simulate also different industrial emission reduction strategies according to the optimal economical/production balance. The system can easily be adapted for emergency use.

A statistical assessment of saturation and mobile sampling strategies to estimate long-term average concentrations across urban areas

Abstract: The objectives of this study were: (1) to quantify the errors associated with saturation air quality monitoring in estimating the long-term (i.e., annual and 5 yr) mean at a given site from four 2-week measurements, once per season; and (2) to develop a sampling strategy to guide the deployment of mobile air quality facilities for characterizing intraurban gradients of air pollutants, that is, to determine how often a given location should be visited to obtain relatively accurate estimates of the mean air pollutant concentrations. Computer simulations were conducted by randomly sampling ambient monitoring data collected in six Canadian cities at a variety of settings (e.g., population-based sites, near-roadway sites). The 5-yr (1998-2002) dataset consisted of hourly measurements of nitric oxide (NO), nitrogen dioxide (NO2), oxides of nitrogen (NOx), sulfur dioxide (SO2), coarse particulate matter (PM10), fine particulate matter (PM2.5), and CO. The strategy of randomly selecting one 2-week measurement per season to determine the annual or long-term average concentration yields estimates within 30% of the true value 95% of the time for NO2, PM10 and NOx. Larger errors, up to 50%, are expected for NO, SO2, PM2.5, and CO. Combining concentrations from 85 random 1-hr visits per season provides annual and 5-yr average estimates within 30% of the true value with good confidence. Overall, the magnitude of error in the estimates was strongly correlated with the variability of the pollutant. A better estimation can be expected for pollutants known to be less temporally variable and/or over geographic areas where concentrations are less variable. By using multiple sites located in different settings, the relationships determined for estimation error versus number of measurement periods used to determine long-term average are expected to realistically portray the true distribution. Thus, the results should be a good indication of the potential errors one could expect in a variety of different cities, particularly in more northern latitudes.

Searching for structure in measurements of air pollutant concentration

Abstract: When studying air pollution measurements at different sites in a spatial area, we may search for a typical pattern, common to all curves, describing the underlying air pollution process in a pre-specified period. Another area of interest to support local authorities in air quality management may be the classification of the different sites in homogeneous clusters and the group ranking that follows. Yet, there is variation in both amplitude and dynamics among the air pollutant concentrations measured at the different monitoring stations. Analyzing such measurements, where the basic unit of information is the entire observed process rather than a string of numbers, involves finding the time shifts or the warping functions among curves. The analysis is much more complicated if we consider a multivariate process, that is, vector-valued air pollutant measurements. Following our previous work where an improved dynamic time-warping algorithm has been developed, especially in the multivariate case, and used both for classifying functional data and estimating the structural mean of a sample of curves, we analyzed the measurements of some air pollutants in Emilia Romagna (northern Italy). In addition, for the univariate analyses, we applied the self-modeling warping function approach, which is also convenient for these data. Indeed, this method was found to be model-free and enough flexible to capture very complex and highly non-linear patterns. Copyright © 2007 John Wiley & Sons, Ltd.

Assessing the impacts of infrastructural road changes on air quality: A case study

Abstract: Air quality (CO, NO, NO 2 , NO X , PM10 and C 2 –C 6 hydrocarbons) was assessed in the Irish town of Monasterevin, before and after the location was by-passed with a new national motorway (M7). Prior to the opening of the motorway, transport between the cities of Dublin and Cork was facilitated by the N7 which ran through Monasterevin, leading to frequent congestion. Weekday air quality improved in the town following the opening of the M7 by-pass, with a reduction in ambient concentrations observed for all compounds except ethane and propane. Slight decreases in average weekend concentrations were observed for CO, NO X , NO, and NO 2 .

Ozone in Spain's national parks and protected forests.

Abstract: In general, it is difficult to measure air pollutant concentrations in remote areas, as they are mostly national parks and protected areas. Passive samplers provide an accurate and inexpensive method for measuring cumulative exposures of different air pollutants. They have been used to collect ozone data in both laboratory and field at different geographical scales. The objective of the present study is to fill the knowledge gap regarding air quality in remote areas of Spain, such as national parks and protected areas. Because there were no systematic data sets on the main air pollutants that could affect these areas, an air quality measurement network was established between 2001 and 2004 on 19 locations inside Spanish national parks and protected areas. The data collected suggest that ozone levels in mountainous areas are high enough to affect sensitive vegetation. Most of the locations registered moderate-to-high ozone levels, with important interannual variability. Altitudinal ozone gradients were observed in most of the parks with complex topography due to the establishment of local circulations that incorporate polluted air masses from polluted airsheds or even long-range transport (i.e., Canary Islands). Different latitude-dependent, yearly cycles were also observed, showing two, one, or no clear peaks depending on the region. These findings extend to the most southerly locations, except in the Canary Islands, where pollution transported from other regions in the upper transport layers probably led to the high concentrations observed.

Understanding Air Emissions from Animal Feeding Operations

Abstract: Summary The major air emissions associated with animal feeding operations are: ammonia (NH 3 ), hydrogen sulfide (H 2 S), nitrous oxide (N 2 O), methane (CH 4 ), carbon dioxide (CO 2 ), particulate matter (PM), vol-atile organic compounds (VOCs), and odor. The air emissions are generated by three major sources: ani-mal production facilities including animal buildings and open lots; manure treatment and storage facilities; and land application of animal manure. Air quality inside animal buildings affects the health of animals and farm workers depending on the levels of exposure. Ambient air quality around the farm affects the health of neighbors. Dust, ammonia, and hydro-gen sulfide emissions from animal feeding operations have the greatest potential for health effects. Odor is a nuisance and affects the quality of life, but the health effects are not fully understood and well documented. In addition to the health effects, air emissions create environmental concerns, such as environmental acid-ity, atmospheric visibility, and global warming.

Analysis of Bogota's Air Quality

Abstract: During this research project we conducted an analysis of the information registered by Bogota’s air quality monitoring network. We built a database that was designed to facilitate the processes of validating and analyzing the air quality data, which were used to quantify the city’s air pollution problem. Our results suggest that air pollutants such as carbon monoxide and sulfur and nitrogen oxides do not represent a major air pollution problem. At the same time, however, the particulate matter ambient air concentrations in Bogota tend to be much higher than the levels suggested by the local air quality standards.

The effect of ambient air pollution on human health

Abstract: The article presents the important issues of the negative effects of ambient (outdoor) air pollution on human health. The focus is on 4 common pollutants: particulate matter, ground-level ozone, nitrogen oxides and sulphur dioxide, and their significant health effects mainly on human respiratory and cardiovascular system even at levels once considered safe.

Morning peak of air pollutant concentrations in urban areas: effect of time lag between emissions and turbulence

Abstract: Primary air pollutants in urban environments, like CO and PM10, show a distinctive diurnal cycle characterized by periods of maximum concentrations in the morning and in the evening. These peaks occur during the times of the day when high emissions combine with a relatively small dispersive capacity of the atmospheric boundary layer (ABL). Moreover, during the morning and evening hours, both the emission rates and the ABL turbulence are highly transient. Therefore, it is reasonable to expect that the timing and the magnitude of the concentration peaks are controlled by the time evolution of the emission rates, the turbulence intensity, and the relative phase between emissions and turbulence.

Concentrations of Toxic Air Pollutants in the U.S. Simulated by an Air Quality Model

Abstract: • Can an Eulerian grid model be used to calculate HAPsconcentrations?ƒDescribe the formulation of a model with air toxicsƒShow results of simulationsƒAnalyze and interpret the results• How do we know that the predictions are realistic?ƒCompare results with measurements• What pieces are we missing?ƒFuture work and needs