Showing papers on "Air pollutant concentrations published in 2002"

Air Pollution : Measurement, Modelling and Mitigation, Second Edition

Abstract: Air Pollutants: Sources and Control of Gases Units for Expressing Pollutant Concentration The Basic Atmosphere The Vertical Structure of the Atmosphere Anthropogenic Emissions Primary Emission Summary Adsorption and Adsorption of Gases Other Air Pollutants Secondary Gaseous Pollutants Emission Interventions Air Pollutants: Particulates Particle Terminology Particle Size Disturbations Aerosol Mechanics Particle Sources Abatement of Primary Particle Emissions Secondary Particles Trends in Particle Emissions Mobile Sources Motor Vehicle Emissions Train Emissions Shipping Emissions Aircraft Emissions Different Models of Transport Measurement of Gases and Particles Methods of Describing Pollutant Concentration Sampling Requirements Gas Sampling Gas Concentration Measurement Quality Control Particle Sampling Particle Measurement Methods Chemical Composition of Aerosol Measurement of Course Particle Deposition Emission Measurement from Stationary Sources Measurement Uncertainty Concentrations and Deposition Gaseous Pollutants Patterns of Occurrence Particulate Matter Dry Deposition of Gases Wet Deposition Total Deposition and Budgets Analysis of an Air Pollution Episode Meteorology and Modelling Meteorological Factors Dispersion Models Gaussian Dispersion Theory Dispersion Theory in Practice Dispersion of Vehicle Emission and Exposure Modelling Receptor Models Box Models Statistical Models Analysis of an Air Quality Data Set The Raw Data Set Period Averages Roses Diurnal Variations Short-Term Events Frequency Disturbations Further Statistical Analyses Indoor Air Quality Building Ventilation Combustion Indoor Organics Sources Bioaerosols Sick Building Syndrome Odour and Ventilation Clean Rooms Mitigation of Air Pollution: The Role of Vegetation Forest Canopy Intervention Particle Deposition to Vegetation Filter Strips Practical Concerns of Vegetation Intervention Effects on Plants, Visual Range and Materials Effects on Plants Visual Range Damage to Materials Responses of Humans and Other Animals Responses of People Effects on Other Animals Greenhouse Gases and Climate Change Our Radiation Environment The Role of Gases The Role of Aerosol Gases and Aerosol Combined Future Scenarios The Main Predictions Feedbacks Global Responses Ozone Depletion and Ultraviolet Radiation Ozone in the Stratosphere Destructive Chemistry The Current Situation Ozone and Ultraviolet Clothing Protection from UV Standards and Legislation UK Legislation EU Air-Quality Legislation UNECE World Health Organization (WHO) EU Industrial Emission Legislation EU Vehicle Emissions US Legislation Legislation in the Asian Region Air Pollution Indices

Assessing exposure to air toxics relative to asthma

Abstract: Asthma is a respiratory disease whose prevalence has been increasing since the mid 1970s and that affects more than 14.6 million residents of the United States. Environmental triggers of asthma include air pollutants that are respiratory irritants. Air toxics emitted into the ambient air are listed in the 1990 Clean Air Act Amendments as hazardous air pollutants (HAPs) if they can adversely affect human health, including the respiratory tract. HAPs include particulate and gaseous-phase pollutants, individual organic compounds and metals, and mixtures. Associations between asthma exacerbation and both particles and indoor volatile organic compounds (VOCs), often referred to as indoor air quality, have been reported. Studies conducted in the United States, Canada, and Europe over the past two decades have shown that most people living in the developed countries spend the majority of their time indoors and that the air concentrations of many air toxics or HAPs are higher indoors than in the ambient air in urban, suburban, and rural settings. Elevated indoor air concentrations result from emissions of air toxics from consumer products, household furnishings, and personal activities. The Relationship of Indoor, Outdoor and Personal Air (RIOPA) study was designed to oversample homes in close proximity to ambient sources, excluding residences where smokers lived, to determine the contribution of ambient emissions to air toxics exposure. The ratios of indoor to outdoor air concentrations of some VOCs in homes measured during RIOPA were much greater than one, and for most other VOCs that had indoor-to-outdoor ratios close to unity in the majority of homes, elevated ratios were found in the paired samples with the highest concentration. Thus, although ambient emissions contribute to exposure of some air toxics indoors as well as outdoors, this was not true for all of the air toxics and especially for the higher end of exposures to most volatile organic air toxics examined. It is therefore critical, when evaluating potential effects of air toxics on asthma or other adverse health end points, to determine where the exposure occurs and the source contributions for each air toxic and target population separately and not to rely solely on ambient air concentration measurements.

Ventilation rates and health

Abstract: While ventilation rates do not directly affect occupant health or perception outcomes, they affect indoor environmental conditions including air pollutant concentrations that may modify the occupants' health or perceptions. This article summarizes the review by Seppanen, et al. of current literature on the relationship of ventilation rates and carbon dioxide concentrations in non-residential and non-industrial buildings (primarily offices) with the health of the building's occupants and with the occupants' perceptions of indoor air quality (IAQ). The review aims to provide a better scientific basis for setting health-related ventilation standards. This summary focuses primarily on the ventilation rate studies.

The efficacy of low emission zones in central london as a means of reducing nitrogen dioxide concentrations

Abstract: This paper considers the effects of different strategies that might be considered to reduce the impact made by road traffic on air pollution in London. The management of road traffic in large urban areas is one of many options being considered to reduce pollutant emissions to meet statutory air pollution objectives. Increasingly, the concept of a low emission zone (LEZ) is being proposed as a means of achieving this reduction. An assessment has been made of different LEZ scenarios in central London, which involve reducing traffic flow or modifying the vehicle technology mix. Methods of predicting annual mean nitrogen dioxide concentrations utilising comprehensive traffic data and air pollution measurements have been used to develop empirical prediction models. Comparisons with statutory air pollution objectives show that significant action will be required to appreciably decrease concentrations of nitrogen dioxide close to roads. The non-linear atmospheric chemistry leading to the formation of nitrogen dioxide, results in a complex relationship between vehicle emissions and ambient concentrations of the pollutant. We show that even ambitious LEZ scenarios in central London produce concentrations of nitrogen oxides that are achieved through a “do nothing” scenario only five years later.

Use of an index to reflect the aggregate burden of long-term exposure to criteria air pollutants in the United States.

Abstract: Air pollution control in the United States for five common pollutants--particulate matter, ground-level ozone, sulfur dioxide, nitrogen dioxide, and carbon monoxide--is based partly on the attainment of ambient air quality standards that represent a level of air pollution regarded as safe. Regulatory and health agencies often focus on whether standards for short periods are attained; the number of days that standards are exceeded is used to track progress. Efforts to explain air pollution to the public often incorporate an air quality index that represents daily concentrations of pollutants. While effects of short-term exposures have been emphasized, research shows that long-term exposures to lower concentrations of air pollutants can also result in adverse health effects. We developed an aggregate index that represents long-term exposure to these pollutants, using 1995 monitoring data for metropolitan areas obtained from the U.S. Environmental Protection Agency's Aerometric Information Retrieval System. We compared the ranking of metropolitan areas under the proposed aggregate index with the ranking of areas by the number of days that short-term standards were exceeded. The geographic areas with the highest burden of long-term exposures are not, in all cases, the same as those with the most days that exceeded a short-term standard. We believe that an aggregate index of long-term air pollution offers an informative addition to the principal approaches currently used to describe air pollution exposures; further work on an aggregate index representing long-term exposure to air pollutants is warranted.

Air pollution in Athens basin and health risk assessment.

Abstract: An inventory of air pollution sources within the Athens basin is carried out for the years 1989, 1992 and 1998 and the results areinputted in a climatological model for predicting ambient concentrations Despite of the significant growth in the numberof road vehicles and the deteriorating traffic, the emissions andambient concentrations of fine particulates, CO, NOx and VOCappear to remain reasonably constant over for the period 1989 to 1998, while these of SO2 and Pb are reduced, mainly due to the renewal of vehicle fleet, the use of catalytic technologies and the improved quality of the used fuel The results further indicate that for CO, NOx and VOC the major source is road traffic, while for PM25 and SO2 both space heating andtraffic share responsibility The air pollutant concentrations monitored by the network of 11 stations are reviewed and statistics related to air quality guidelines are presented As fine particulate levels are not monitored, approximate PM25and PM10 concentrations are derived from black smoke ones on basis of experimentally determined conversion factors The computed and monitored air pollution levels are compared and found in reasonable agreement The results of the above analysisshow that the levels of all `classical' pollutants, with the exception of SO2 and Pb, exceed significantly the WHO guidelines and are thus expected to exert a significant healthimpact The latter could be quantified in relation to the PM25 or PM10 levels on the basis of risk assessment information developed by the World Health Organization (WHO) The results show that the existing levels of fine particle concentrations in Athens increase significantly the mortality and morbidity, and reduce the average longevity of the entirepopulation from 13 to 17 years

Evaluation of air pollution trends in Istanbul

Abstract: Previously, SO2 and PM10 (particulate matter less than 10 Bm in size) concentration distributions have been investigated in order to assess air pollution in Istanbul during the winter season (November–March) in which the concentration of these pollutants had reached formidably high levels due to the consumption of low-quality fuels (mainly coal) for residential heating. In this study, the effect of the increased share of natural gas and high-quality coal consumption in residential areas on air pollution levels was investigated. Modelling employing the method of kriging by spherical interpolation was used to obtain the concentration distribution of these pollutants, and spatial distributions of concentrations were generated. The pollution map obtained by this method indicated that increased usage of natural gas and high-quality coal in residential areas significantly improved air quality.

Hazardous Air Pollutant Handbook : Measurements, Properties, and Fate in Ambient Air

Abstract: Hazardous Air Pollutants: A Brief Introduction Background The List of Hazardous Air Pollutants Impact of the HAPs List Organization of Information in this Book References The Title III Hazardous Air Pollutants: Classification and Basic Properties The 188 Hazardous Air Pollutants: Diversity and Derivation Some Common Features of the Title III HAPs Chemical and Physical Properties of the 188 HAPs Polarizability and Water Solubility as Defining Characteristics of Polar and NonPolar VOCs References Measurement Methods for the 188 Hazardous Air Pollutants in Ambient Air Introduction Background Survey Approach Status of Current Methods HAPs Method Development: Future Directions References Concentrations of the 188 HAPs in Ambient Air Introduction Survey Procedures Ambient Air Concentrations of HAPs Data Gaps Recent Data for High Priority HAPs Summary References Atmospheric Transformation Products of Clean Air Act Title III Hazardous Air Pollutants Introduction Experimental Approaches for the Study of HAP Transformations Hazardous Air Pollutant Transformations Transformations of 33 Urban Air Toxics Transformations of Other Atmospheric Chemicals Summary References Appendix Index

Development of transport related air pollutants modelling for an urban area

Abstract: The number of vehicles in India is growing, leading to overcrowded roads and air pollution. Research studies conducted to investigate the effects of transport on air pollution are reviewed. Ambient air pollution due to carbon monoxide, hydrocarbons, nitrogen oxides, sulphur dioxide and suspended particulate matter was determined at selected locations in Delhi. Data on traffic volume were collected at the same locations. Regression equations were developed to indicate the trends of air pollutants with respect to traffic. Carbon monoxide levels were correlated with the number of petrol-driven vehicles. Nitrogen oxide and sulphur dioxide levels were correlated with the number of diesel-driven vehicles. The ability of CALINE4 software to predict the carbon monoxide concentrations in Delhi was examined. Predicted values were generally conservative. Strategies for controlling air pollution are discussed.

A review of air quality management areas in Great Britain : implications for land-use planning

Abstract: With air quality now a clearly recognised material consideration in land use planning processes in GB, the designation of air quality management areas (AQMAs) in over a quarter of local authorities in England, Scotland and Wales is causing local planners to re-evaluate the potential impact of development on local air quality Traffic emission sources account for over 95% of the AQMAs designated in the UK, with predicted exceedences of the long-term nitrogen dioxide (NO 2 ) air quality objective causing their designation in the main Designation of an AQMA requires an air quality action plan to reduce exceedences of the air quality objectives, and this will require actions to address traffic flow, generation and overall traffic movements in our rural and urban areas alike Local authorities, through their air quality action plans and strategies, and more importantly their local transport plans and local development plans will need to identify methods for ensuring air pollutant concentrations do not deteriorate further in areas where the public is exposed Locations designated as AQMAs therefore provide the starting point for identifying specific areas where planning processes should be focused on improving local air quality This paper examines how the various spatial shapes ansd scales of AQMA designations may affect land-use planning processes, and how the scientific assessment process undertaken to determine AQMA locations may conflict with, or assist in informing the strategic and development control planning processes operating within local government in GB

Sofia: An Integrated Computational Model For Air Quality.

Abstract: This paper presents a numerical model for predicting air pollutant concentrations in a 3D geo-referenced framework. The model (SofIA = Software de Impacto Atmosferico) is based on a Gaussian dispersion criterion. A wide range of sources arising from a typical urban study area are included in it, i.e. mobile sources, residential and commercial emissions, open burning, dust resuspension and stack releases. As output, the model gives the concentration fields for the considered pollutants, and both short-term and long-term exposures. In order to show the model capabilities, the simulation of the air quality in a megacity is presented. Model calibration and validation procedures are discussed. Although the available database to feed the model is reduced both in quality and quantity, a relatively good agreement between measurements and predicted concentrations is found. In this way, it is shown that the model is able to represent the main characteristics of the local air quality. The impacts of potential mitigation measures on the local air quality are also presented, including long-term NOx and PM10. Predictions for the period 2000-2012 are presented. Finally, some recommendations about model improvement are discussed.

Measurements of roadside air pollution and traffic simulations

Abstract: Air pollution levels at the roadside were measured and trallic flows were analyzed in order to determine the dynamic features of air pollutants. Moreover, a t.raflic simulator was used to simulate observed tratTic flows and to evaluate proposed strategies. It was found that temperature-inversion above the road surface due to vehicle exhaust emissions might suppress the vertical dispersion of air pollutants in the early morning. It was also found that concentrations of air pollutants at the roadside near traffic lights had periodicity corresponding to the traffic signal cycle. But the phase of nitrogen dioxide concentration was different fkom that of suspended particulate matter. It was found that total traffic volume depended mainly on the number of small car, but level of air pollution along the roadside seemed to depend on mainly on the number of heavy-goods vehicles, A vehicle-actuated signal-control system that enables reduetion of the air pollution level at the roadside is proposed.