Lichens as litmus for air pollution: a historical review

The literature on the relationships between lichens and air pollution is reviewed, with particular reference to the development of the concepts governing their use as indicators of air pollution levels. Lichens are particularly sensitive to sulphur dioxide which acts by the destruction of chlorophyll. By considering both the species present and their abundance, zones indicative of mean air pollution levels can be quickly mapped. The way in which some species respond in different regions varies and so zonal scales can only be reliably applied in the areas where they were devized. Only in a few cases has it been possible to correlate lichen zones with particular sulphur dioxide concentrations, principally because of a lack of physicochemical measurements; but even where such correlations are not possible, lichen zones provide a rapid qualitative means of assessing the effects of air pollution. Maps showing the type of data obtained by this method are presented, and a table summarizes the published work on major cities, towns, industrial plants, and in larger geographical regions.     

Cities and pollution

A study of air, water, noise and land pollution in Greater Manchester is described. Trends, generally downwards, in overall pollution levels are reviewed and the determinants of these levels discussed. The large variation in these determinants between the 71 local authorities which comprised Greater Manchester before reorganisation in April 1974 is reflected in the prevailing pollution levels. The differences in smoke and sulphur dioxide concentrations, average river and canal quality, traffic density (a measure of air and noise pollution from motor vehicles) and the proportion of land polluted by wastes are analysed. Disadvantaged areas, which experience the highest levels of most pollutants, are characterised by high population density, by high industrial activity and by low affluence. They generally appear to be affected by pollution exported by more affluent areas. It is recommended that increased attention be paid to the role of land use planning in controlling pollution and to the development of broader‐based systems of environmental inspection. The need for increased monitoring of pollution levels in the disadvantaged areas is stressed.     

Micromap plots to visualize air pollution at national and local level in Korea

Air pollution is a persistent and pervasive environmental problem with health implications and economic costs for society. In this study, we introduce a new approach for visualizing air pollution data and describe how spatial patterns of air pollutants can be examined simultaneously using linked micromap plots. To explore the potential utility of the plots, we analysed and visualized Korean air pollution data for the period 1989–2012 at national and local level. Our analysis revealed that sulphur dioxide (SO₂), fine particle and carbon monoxide decreased for the period, but ozone increased uniquely. The pollution level of Jeju was lowest. Daegu and Gyeonggi showed the highest levels. Daegu had highest values in both range and interquartile range. SO₂ decreased the most in Gangwon which had formerly had the largest number of coal mines. Regions with high levels of fine particles were located mainly in the northwest, probably influenced by dust, and in the southeast, industrialized areas.     

Air pollution trends in the town of Turin in the years 1973–1986

In Turin since 1973, a pollution control network (subsequently enlarged), to monitor sulphur dioxide, carbon monoxide, nitrogen oxides, nitrogen dioxide, ozone, particulate matter, together with major meteorological parameters has existed. Pollution measurements carried out so far show changes through the years. Comparison of data between different monitoring stations, related also to different periods of the year, permits the calculation of the contribution of the different sources with respect to each pollutant. Although improvements have been achieved, values for carbon monoxide and particulate matter exceeding the Italian national air quality standards are frequent near streets with a high volume of traffic streets. The problem of high concentrations of sulphur dioxide seems to have been solved.     

Performance assessment of air quality monitoring networks using principal component analysis and cluster analysis

This study aims to evaluate the performance of two statistical methods, principal component analysis and cluster analysis, for the management of air quality monitoring network of Hong Kong and the reduction of associated expenses. The specific objectives include: (i) to identify city areas with similar air pollution behavior; and (ii) to locate emission sources. The statistical methods were applied to the mass concentrations of sulphur dioxide (SO₂), respirable suspended particulates (RSP) and nitrogen dioxide (NO₂), collected in monitoring network of Hong Kong from January 2001 to December 2007.     

Priority among air pollution factors for preventing chronic obstructive pulmonary disease in Shanghai.

The problems that city environmental protection planners face are how important the air pollution exposures are in relation to chronic obstructive pulmonary disease (COPD) in local residents and which factor should be controlled most urgently. The purpose of our study is to determine the control priority among ambient sulphur dioxide (SO2) inhalable particulates (IP) and indoor use of coal to prevent COPD in residents of the city. Ambient air pollution is mainly from SO2 and IP(< 10 nm). Indoor air pollution is mainly from the use of coal for heating and/or cooking. Distribution of ambient SO2, and IP concentrations were described using a quartic trend surface simulation. When stratified by two extreme levels of ambient SO2 and IP and types of fuel used indoors, eight local area populations in four communities with different combinations of exposure levels were selected. In each community a local area population mostly using coal and one mostly burning gas was chosen. Chronic obstructive pulmonary diseases (COPD, ICD 490-493) including chronic bronchitis, asthma and emphysema, are a major cause of death in residents of Shanghai. The relationship between the three air pollution factors and their health effects were analyzed at the level of mortality (1978-1987, 232,459 person-years), prevalence of symptoms (12,037 persons) of COPD, lung function and non-specific immunologic function (514 women). The results show that indoor use of coal has stronger associations with health than estimated exposure to ambient SO2 or IP.     

生物活性炭滤池初期运行效果评价

结合相城水厂活性炭滤池的初期投运过程,研究了生物膜的自然生长情况及其对水中有机污染物的去除效果.通过对比气、水反冲和单水冲两种模式的实际效果,探讨了不同冲洗方式对生物膜恢复净水效果的影响.结果表明:环境温度偏低和较好的水质将在一定程度上延长炭粒表面的自然挂膜速度,生物膜一旦有效形成,可在常规净水工艺基础上进一步提高对氨氮、耗氧量和TOC等指标的去除效果,切实保证出厂水的生物稳定性.     

Multi-level effects of sulphur-iron interactions in freshwater wetlands in The Netherlands

Although sulphur deposition rates in Europe have considerably decreased over the last decades, sulphate concentrations in freshwater wetlands are still high, as a result of drainage, nitrate pollution, and increased sulphur loads in rivers. High sulphur fluxes may cause sulphide toxicity and eutrophication, and strongly interfere with the biogeochemical cycling of iron and phosphorus. In the present study the ecotoxicological interactions between sulphur, phosphate, iron, and trace metals in freshwater wetlands are reviewed.     

Mapping indoor overheating and air pollution risk modification across Great Britain:A modelling study

Housing has long been thought to play a significant role in population exposure to environmental hazards such as high temperatures and air pollution.However,there is sparse data describing how housing may modify heat and air pollution exposure such that housing's role in poor health and mortality from these hazards may be estimated.This paper describes the development of individual-address level indoor overheating and air pollution risk modifiers for Great Britain,for use alongside historical weather,outdoor air pollution,population socio-economic data,and mortality data in a large-scale epidemiological investigation.A geographically-referenced housing stock database was developed using the Homes Energy Efficiency Database(HEED)and the English Housing Survey(EHS).Simulations of unique combinations of building,fabric,occupation,and environment were run using a modelling framework developed for Energy Plus8.0,estimating indoor temperature metrics,indoor/outdoor ratio of pollution from outdoor sources,and indoor air pollution from multiple indoor sources.Results were compiled,matched back to individual properties in HEED,and mapped using Geographical Information Systems(GIS).Results indicate urban areas had higher numbers of buildings prone to overheating,reduced levels indoor air pollution from outdoor sources,and higher air pollution from indoor sources relative to rural areas,driven largely by variations in building types.The results provide the first national-scale quantitative estimate of heat and indoor air pollution modification by dwellings,aggregated at levels suitable for inclusion in health analysis.     

Addition of Olfs from Different Pollution Sources,determined by a Trained Panel

The purpose of this study was to predict how indoor air is perceived when polluted by different materials simultaneously. A panel of five trained judges was exposed to air polluted by each of 11 different single pollution sources. The panel was also exposed to 13 pair combinations of these single pollution sources and to one combination of five sources. The pollution sources comprised typical indoor building materials, materials from ventilation systems and other frequently occurring indoor pollution sources. The results indicate that the total sensory pollution load in a space may, as a first approximation, be predkted by simple addition of the olf values of the single sources.     

Sulphur leaching from headwater catchments in an eroded peatland, South Pennines, U.K

A detailed investigation into sulphur leaching in peatland headwater catchments in the South Pennines, UK shows that, despite significant reductions in sulphur emissions, sulphur remains a key acidifier. This sulphur can be considered as legacy atmospheric pollution, stored within the peat by processes of dissimilatory sulphate reduction and now being leached into the region's surface waters. Persistently lower water tables at gully edge locations define a thick erosional acrotelm that is vulnerable to aeration, oxidation and flushing throughout the year, and not solely confined to periods of drought. Stream discharge behaves as a two-end member system, whereby pre-event water, rich in DOC and sulphate, is diluted by event water as a result of event water flowing through fast flow pathways such as macropores and overland flow. A rapid increase in water table elevation during the storm and a decrease in elevation after the storm indicate that event water has infiltrated the peat and has then been released into the stream. Streamwaters in peat dominated upland catchments with high densities of gullying have high concentrations of sulphate and low concentrations of DOC, whereas the reverse is true for those catchments with low densities of gullying. This is consistent with the concept that high concentrations of sulphate can suppress the solubility of DOC. A significant store of sulphate exists within South Pennine peats, and continued gully erosion will enhance sulphur leaching meaning that the timescale involved for any depletion is uncertain. It is therefore important that models predicting recovery from acidification in these upland systems include an understanding of how this stored sulphur is being leached, especially with respect to gully erosion, climate change and reduced precipitation.     

The effect of various types of soot on the behaviour of sulphur dioxide in the air investigated on model systems

The effect of four different types of oil soot on the behaviour of sulphur dioxide in the air was investigated on model systems. The efficiency of soot for removing SO₂ from the air stream increases with increased active surface of soot, length of contact and relative humidity.The experimental results indicate that the removal of SO₂ from the air stream in contact with soot is a result of SO₂ adsorption because all removed SO₂ is desorbed from soot at a temperature of 250°C.     

Observations on local and national air quality indices

An Air Quality Index is defined as a single term, usually a number, used to describe the degree of contamination of the ambient air. The concept of an air quality index is not new and such an index could be quite useful provided that the index does not over-simplify the situation nor cover up gaps in our knowledge. Some basic information on an assortment of air pollution indicators that have been used nationally and internationally either for public information and/or alert systems is provided.In most of these indicators, aerosols, usually measured by light absorption techniques, and sulphur dioxide, were the pollutants incorporated into the index. Other pollutants used less frequently included carbon monoxide, oxides of nitrogen, hydrocarbons and oxidants.After listing the requirements of a national air quality index a second list of items is presented which would negate the validity of any comprehensive nation-wide index. It is thus concluded that considering the present state of our knowledge and vastly different geographical, topographical and meteorological areas of a country such as Canada the development of a nation-wide air quality index is not recommended.     

Blowing in the wind: the impact of China's Pearl River Delta on Hong Kong's air quality

The local versus regional nature of Hong Kong's air pollution remains an unresolved issue with important policy implications. Specifically, the potential benefits of different air quality improvement efforts will vary dramatically, depending upon the nature of the pollution. This multi-disciplinary paper attempts to resolve the issue, using a time series, cross-sectional panel of pollution data from Hong Kong and southern China, along with weather variables from Hong Kong. An econometrically-based structural model of Hong Kong pollution levels is constructed, and Granger causality tests are conducted. Then, using results from the structural model, the health impacts on Hong Kong residents of reductions in mainland China's pollution are estimated and valued in economic terms. Results indicate that for the pollutants PM(10) and NO(2) causality runs in both directions, highlighting the regional nature of the air pollution problem. However, the potential health benefits resulting from reductions in southern China's pollution are relatively small. In US dollar terms, the averted mortality benefits of a large China-focused clean up are approximately $40 million, but the benefits of a more modest Hong Kong-focused effort are nearly $200 million. The resulting policy implication is that Hong Kong's primary pollution control efforts should lie at the local level.     

Indoor Air Pollution: A Public Health Perspective

In developed and developing countries, indoor air pollutionis gaining increasing prominence as a public health problem. Time-activity studies and exposure surveys have shown the dominant contributions of indoor environments to population exposures for many pollutants. Mounting epidemiological evidence documents adverse health effects of indoor pollutants and risk assessments indicate that indoor carcinogens may contribute substantially to the population's burden of lung and other cancers. Unacceptable indoor air quality has also been identified as a common cause of symptoms. This paper addresses the public health problem posed by indoor air pollution, offering a schema for categorizing adverse health effects of indoor air pollution, and considers the complexiry of estimating the full scope of the problem     

Urban air pollution and solar energy

The design and performance of solar energy systems for many potential applications (industrial/residential heat, electricity generation by solar concentration and photovoltaics) will be critically affected by local insolation conditions. The effects of urban air pollution are considered and reviewed. A study of insolation data for Alhambra, California (9 km south of Pasadena) shows that during a recent second-stage photochemical smog alert (≥0.35 ppm ozone), the direct beam insolation at solar noon was reduced by 40%, and the total global by 15%, from clean air values. Similar effects have been observed in Pasadena and are attributable primarily to air pollution. Effects due to advecting smog have been detected 200 km away in the Mojave Desert. Preliminary performance and economic simulations of solar thermal and photovoltaic power systems indicate increasing non-linear sensitivity of life cycle plant cost to reductions in insolation levels due to pollution.     

Toxic air pollutants--assessing their importance

Toxic air pollutants (TAP) are a major concern for air pollution scientists, yet our state of knowledge concerning these contaminants is not comprehensive. The paper that follows contains a critical analysis of various aspects of TAP such as regulatory controls, sources, atmospheric concentrations and health impacts. Throughout the discussion specific examples are used to illustrate particular points, and while a large body of information is referenced, the literature review is not meant to be exhaustive. Toxic air pollutants present a challenge to the air pollution scientist; the true significance of these environmental contaminants on human health has not yet been quantified, although certain studies appear to indicate that they may have important impacts on respiratory health.     

Air quality status in Greater Thessaloniki Area and the emission reductions needed for attaining the EU air quality legislation

This paper aims at imprinting the urban air quality status and assessing the impact of various emission reduction scenarios on the photochemical and particulate matter air pollution levels in the Greater Thessaloniki Area, Greece. In particular, it is investigated under which conditions compliance with the EU air quality legislation can be achieved. For this purpose, the Ozone Fine Structure model is applied for a full calendar period (reference year 2002), as well as for specific scenarios, corresponding to predefined emission reductions for 2010. The model results for photochemical and particulate matter air pollution levels in 2002 agree fairly well with the observations. Predictions for 2010 indicate that significant improvement towards the EU legislation requirements can be achieved for certain emission reduction scenarios. However, an overall strategy will also have to include additional local scale measures.     

A Survey Of Health Effects Of Air Pollution On Peasant Farmers In Benue State,Nigeria

This paper examines the health effects due to air pollution on peasant farmers in Benue State, Nigeria. The study is based on the review of epidemiological data collected from clinics and hospitals in the State. The diseases found to be prevalent in the study area include allergic asthma, pulmonary tuberculosis, pneumonia, upper respiratory tract infection (URTI), chronic bronchitis and visual impairment. The ambient air quality in the state is far worse than national and international ambient air quality standards. This gives an indication of a strong correlation between the diseases and the air pollutants. The environmental impact matrices of the patients versus diseases indicate that pollution is already affecting the quality of life and productivity of the people. Since agriculture is the principal occupation of Nigerians, accounting for about 60% of employment, a case is made for an intensification of environmental education, especially among the rural farmers.     

Biogeochemical cycles as integrative and spatial models for the study of environmental pollution (the example of the Sulphur cycle)

This paper stresses the need for an approach to pollution of the total physical environment. An ecosystematic approach is suggested whereby biogeochemical cycles are identified as models which can integrate all physical environment components and also provide information on the forms of elemental pollution so that, for example, the spatial aspects of the problem can be identified. The sulphur cycle is used as an example to illustrate how a “pollution component”; of this naturally occuring element can be identified to show where and when excess accumulations can occur sufficient to cause “pollution.”;