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Urban air pollution patterns, land use, and thermal landscape: an examination of the linkage using GIS.

This article investigates the relationship of local air pollution pattern with urban land use and with urban thermal landscape using a GIS approach. Ambient air quality measurements for sulfur dioxide, nitrogen oxide, carbon monoxide, total suspended particles, and dust level were obtained for Guangzhou City in South China between 1981 and 2000. Landsat TM images and aerial photo derived maps were used to examine city's land use and land cover at different times and changes. Landsat thermal infrared data were employed to compute land surface temperatures and to assess urban thermal patterns. Relationships among the spatial patterns of air pollution, land use, and thermal landscape were sought through GIS and correlation analyses. Results show that the spatial patterns of air pollutants probed were positively correlated with urban built-up density, and with satellite derived land surface temperature values, particularly with measurements taken during the summer. It is suggested that further studies investigate the mechanisms of this linkage, and that remote sensing of air pollution delves into how the energy interacts with the atmosphere and the environment and how sensors see pollutants. Thermal infrared imagery could play a unique role in monitoring and modeling atmospheric pollution.

Air Pollution↗

The experience of mutation rate quantitative evaluation in connection with environmental pollution (based on studies of congenital anomalies in human populations).

For 3 years genetic monitoring of congenital anomalies (CA) has been carried out in three Ukrainian towns essentially different in the level of air pollution: the most polluted, Mariupol (M.); medium polluted, Zaporozhye (Z.); and relatively clean, Simpheropol (S.). In this work we present the results of this study. Eighteen CAs being used in the International Clearinghouse program were registered during the first year of life. For each case of CA an individual questionnaire was filled in. It included practically all known causes of malformations. Similar questionnaires were filled in for cases of normal birth outcome. The estimation of newborns of control groups was made according to a score of 9-10 on the Apgar scale. The questionnaires were completed by physicians in all maternity hospitals and children's clinics and based on the information obtained from mothers. Multiple malformations, dominant and X-linked CA in M. were 2.6-3.1 times more frequent than in S. The frequency of new mutations was 0.45-0.95 and 0.17-0.47 per 10(3) births respectively. No differences in multifactorial and recessive CA were noted. The mathematical method (so-called statusmetrical analysis) was used to indirectly determine the part of CAs of unknown etiology (probably of mutation origin) in the total number of CAs. Their quota in Z. and M. was 1.2-1.5 times more than in S. The advantage of statusmetrical analysis lies in the absence of any restrictions connected with a large number of parameters which describe the object's status. It makes it possible to analyze tens, even hundreds of factors (along with the increased number of parameters the reliability of the conclusions increases) and range them in accordance with their validity. Genetic consequences of chemical pollution were estimated in biological equivalents Röntgen (BER). In M. they were equal to the effect of irradiation at doses of 180-300 BER (230 BER, central estimate) over 30 years. In the polluted towns (M. and Z.) the relation between average annual general emission of atmospheric pollutants (M./Z.) was 2.21, the frequency of dominant and X-linked CA 2.20 and of new skeleton mutations 2.24. The difference of mutation rate in the towns studied was due to the dynamics of demographic processes.

Abnormalities, Drug-Induced↗

Pollution episodes at Venice related to weather types: an analysis for a better predictability.

In order to obtain a rational strategy for the control and management of emissions from the industrial area of Venice, determination of the air quality is made from different perspectives. A source-receptor oriented approach shows a remarkable scatter of data due to the complex source field and variability of atmospheric conditions at a coastal site. As many pollution episodes are initiated by local diffusion potentials induced by the interaction between topographic irregularities (i.e. Alpine chain and Adriatic Sea) and the mesoscale atmospheric circulation system, a correlation between pollution events and synoptic conditions is made. Two periods of two years each were considered, the former characterized by very frequent, moderate episodes, the latter by more rare but potentially more severe episodes, although the emission rate was reduced. Four different criteria (i.e. weather types as classified by the U.K. Meteorological Office, by Borghi and Giuliacci, and by Urbani, and the passage of fronts) are considered and compared in order to describe the synoptic conditions and to make a reasonable prediction of the local dynamic climatology. A risk index (RI) is computed for each weather type. The U.K. classification appears to be the most suitable as it classifies the maximum number of synoptic maps and has the greatest spread of RI, thus making a more sound prediction. The analysis shows that the pollution episodes are associated with instability phenomena, i.e. passage of fronts or the onset of moderate to fresh winds, and not with stationary conditions. Also, the areal extension over which the highest pollution levels are recorded is related to particular weather types. The statistics of the meteorological weather types occurring during the pollution events give satisfactory results for some weather types, especially for those correlating highly or poorly with pollution events.

Air Pollution↗

Spatial and temporal patterns of airborne metal pollution: the value of low technology sampling to an environmental epidemiology study.

To investigate an epidemic of respiratory cancer in Armadale, central Scotland, its air pollution was studied. During a period of 18 months, low technology samplers were exposed at 47 sites in the town to monitor the local variations in contamination by atmospheric metals. The samplers were two types of lichen and two types of moss, one of each type being a transplant and the other an in situ sampler. Following each exposure, the comparability of the samplers' uptake and retention of the metals was assessed. The sources of the metals and the effects of environmental variables on the pollution patterns were investigated through statistical analyses of spatial and temporal trends in the data. The spatial patterns of the metals indicated the steel foundry in the town as the major source of most of the pollutants. The temporal patterns, although less statistically significant, suggested the pollution might have been affected by some meteorological factors and by the foundry's output, but not by the output of the other main industry in the town, i.e. a brickworks. The types of sampler showed a general similarity of pollution pattern, but with some differences which indicated that some types of sampler were more suitable than others for particular forms of survey. Low technology sampling can provide information about short-distance and short-term changes in the patterns of airborne pollution by metals, thereby assisting the interpretation of epidemiological patterns of respiratory disease.

Air Pollutants↗

[Development of an exposure index of air pollution caused by motor vehicles for use in epidemiological studies].

Air pollution due to motor vehicles is a worrying issue, in particular in the urban environment, all the more as a number of pollutants such as benzene and PAH are known to have carcinogenic effects. Epidemiological studies seem to be required, so a cumulated score of exposure must be developed. A correlation with pathology should be investigated. The calculation of an index of exposure to motor vehicle-related pollution requires a good assessment of pollutant emissions and a precise knowledge of pollutant transfer mechanisms by advection and spreading in built-up areas. In this study, it is proposed to use current theoretical and experimental knowledge to develop a calculation algorithm for this index. The following issues will be addressed in the presentation: an analysis of epidemiological requirements and of constraints of data acquisition using questionnaire surveys; a model for assessing, for each residential area, the average annual concentration of gaseous pollutants from motor vehicles. It will consider the environment geometry, traffic emissions and wind distributions. The model CALINE3 is used for open areas near roads and highways and the Danish model OSPM is introduced for street canyon environments.

Air Pollutants↗

Investigating groundwater pollution from different sources with combined biological and chemical methods.

This paper reviews groundwater pollution caused by the disposal of untreated effluents of a dye factory located 20 km to the west of Nicosia (Cyprus). The task of the work was to investigate the nature of the pollution and differentiate it from other possible pollution sources in the area. It focused on toxicity testing and biofractionation in order to address the most toxic pollutants and, on the evaluation of GC/FID profiles for investigating the connection between groundwater pollution and the effluents. This connection was successful due to a multiple comparison amongst the GC/FID profiles resulting from the polluted groundwater, the water from the reference areas and the dye effluents.

Coloring Agents↗

Indoor and outdoor pollutants and the upper respiratory tract.

The health effects of both indoor and outdoor air pollutants are of increasing concern. The health effects of outdoor air pollutants traditionally have been assessed through measurements of lower respiratory tract changes. However, it has been shown that one outdoor air pollutant, sulfur dioxide, decreases nasal mucus flow and increases nasal airway resistance. Along with cigarette smoke, indoor air pollutants such as formaldehyde, cadmium, and ammonium or sulfate ions have been shown to alter upper airway mucociliary function. Emissions from wood stoves are known to irritate the upper airways. Measurement of nasal airway resistance using posterior rhinomanometry allows quantification of nasal function. This technique recently has been used to demonstrate that adolescents with allergic asthma have increased work of breathing after inhalation of 0.5 ppm sulfur dioxide. Another study using posterior rhinomanometry showed that clerical workers had increased work of breathing after exposure to carbonless copy paper as compared with bond paper. This brief review of upper respiratory tract changes after pollutant exposure should serve as a reminder that a complete clinical history must include questions designed to ascertain the patient's exposure history to both outdoor and indoor air pollutants. These exposures can have a major impact on the health of the upper respiratory system.

Air Pollutants↗

Air pollutants increase gene expression of the vasoconstrictor endothelin-1 in the lungs.

Inhalation of urban pollutants elevates the circulating levels of the vasoactive peptides endothelin (ET)-1 and ET-3 in rats. This effect could explain the association between episodic variations of urban pollutants and acute cardiopulmonary morbidity and mortality documented in epidemiological studies. Because the lungs are the primary source of circulating ET-1 and the main site of clearance from circulation, we investigated the response of endothelin system genes in the lungs of Fischer-344 rats after 4-h nose-only inhalation of 0.8 ppm ozone plus 49 mg/m(3) EHC-93 (Ottawa particles). The mRNA levels for preproET-1, preproET-3, endothelin-converting enzyme (ECE)-1, and ET receptor subtypes A and B were determined at 2 h, and 1, 2, 3, 7, and 14 days after exposure. The pollutants induced preproET-1 and ECE-1 (P<0.05) after 2 h, consistent with the notion of increased synthesis and conversion of the peptide ET-1 in lung endothelial cells. PreproET-3 mRNA was down-regulated at 2 h post-exposure (P<0.05), and returned to control levels by 24 h, indicating that induction of ET-3 in the lungs is not responsible for the sustained elevation of ET-3 in plasma reported after inhalation of pollutants. Our results indicate that lung endothelin system genes respond rapidly and transiently to inhalation of urban pollutants, consistent with the dynamics of urban pollutant health effects in the human population.

Administration, Inhalation↗

Assessment of airborne heavy metal pollution by aboveground plant parts.

Italian stone pine (Pinus pinea L.) and oleander (Nerium oleander L.) leaves, bark and wood samples were collected at different sites around an industrial area (Huelva, SW Spain) and compared with samples of the same species from a background site. Samples were analysed with respect to the following pollutants: Al, Ba, Cr, Cu, Fe and Pb by ICP-AES. The suitability of different plant parts as biomonitors of pollution was investigated. In pine samples from the polluted sites the ratio of concentrations between bark and wood was high for Al, Ba, Cu and Fe, whereas no differences were found in samples from the unpolluted area. No differences were detected in oleander for the same ratio. In the oleander species, the ratio between leaves and wood concentration allowed to distinguish between control and polluted sites. The ratio of the concentration between leaves and wood was elevated for Al, Ba and Fe in pine samples from the polluted sites. The ratio of the concentration in bark or leaves to their concentration in wood might be useful to detect inorganic atmospheric pollutants.

Air Pollutants↗

The use of different enzymes in feral freshwater fish as a tool for the assessment of water pollution in South Africa.

Selected enzymes in the organs/tissues of two fish species (Oreochromis mossambicus and Labeo umbratus) were evaluated as biomarkers of water pollution in warm- and cold-water systems. The fish were caught using standard techniques during two high-flow and two low-flow surveys. The results indicated that the fluctuating enzyme activities measured were not a result of pollution but could be initiated as a result of (1) no or too little pollution, (2) handling of the fish, and (3) struggling in the nets. Furthermore, most of the enzymes are nonspecific for the specific pollutants present. It is concluded that the selected enzymes could not be successfully employed as biomarkers of water pollution when the organisms are sampled from a polluted water source.

Animals↗

Relationship between air pollution and daily mortality in a subtropical city: Taipei, Taiwan.

Air pollution has been associated with daily mortality in numerous studies over the past decade. However most of these studies were conducted in the United States and Europe with relatively few done in Asia. In the current study, the association between ambient air pollution and daily mortality in Taipei, Taiwan's largest city which has a subtropical climate was undertaken, for the period 1994-1998 using a case-crossover analysis. This design is an alternative to Poisson time series regression for studying the short-term adverse health effects of air pollution. The air pollutants examined included particulate matter (PM(10)), sulfur dioxide (SO(2)), ozone (O(3)), nitrogen dioxide (NO(2)), and carbon monoxide (CO). The largest observed effect, which was without statistical significance, was seen for NO(2) and CO levels on deaths due to respiratory diseases (ORs=1.013 and 1.014, respectively). The well established link between air pollution levels and daily mortality may not be as strong in cities in subtropical areas, although other factors such as differences in pollutant mix or the underlying health of the population may explain the lack of a strong association in this study. Further studies of this type in cities with varying climates and cultures are needed.

Air Pollution↗

Genetic effects of air pollution on forest tree species of the Carpathian Mountains.

The effects of air pollution on the genetic structure of Norway spruce, European silver fir and European beech were studied at four polluted sites in Slovakia, Romania and Czech Republic. In order to reduce potential effects of site heterogeneity on the health condition, pair-wise sampling of pollution-tolerant and sensitive trees was applied. Genotypes of sampled trees were determined at 21 isozyme gene loci of spruce, 18 loci of fir and 15 loci of beech. In comparison with Norway spruce, fewer genetic differences were revealed in beech and almost no differentiation between pollution-tolerant and sensitive trees was observed in fir. In adult stands of Norway spruce, sensitive trees exhibited higher genetic multiplicity and diversity. The decline of pollution-sensitive trees may result thus in a gradual genetic depletion of pollution-exposed populations of Norway spruce through the loss of less frequent alleles with potential adaptive significance to altered stressing regimes in the future. Comparison of the subsets of sensitive and tolerant Norway spruce individuals as determined by presence or absence of discolorations ("spruce yellowing") revealed different heterozygosity at 3 out of 11 polymorphic loci.

Abies↗

Diet-mediated effects of heavy metal pollution on growth and immune response in the geometrid moth Epirrita autumnata.

The potential capacity of larval growth and immune response traits of the autumnal moth to adapt to heavy metal polluted environment was tested experimentally. Both the relative growth rate (RGR) and pupal weight were significantly higher in control trees than on polluted trees, indicating that metal pollution prevented the insect from achieving maximal growth on birch leaves. Larval growth rates of different broods differed significantly between metal contaminated and control birches. However, pupal weight of broods, which is considered more important for fitness than growth rate, in response to pollution did not differ. Immune response was significantly higher in moths exposed to pollution than in moths that were exposed to control environment suggesting that pollution enhances the immune defense of defoliators. Encapsulation rate tended to differ between broods indicating that the immune function has potential to respond to selection.

Adaptation, Physiological↗

Potential assessment of a neural network model with PCA/RBF approach for forecasting pollutant trends in Mong Kok urban air, Hong Kong.

The forecasting of air pollutant trends has received much attention in recent years. It is an important and popular topic in environmental science, as concerns have been raised about the health impacts caused by unacceptable ambient air pollutant levels. Of greatest concern are metropolitan cities like Hong Kong. In Hong Kong, respirable suspended particulates (RSP), nitrogen oxides (NOx), and nitrogen dioxide (NO2) are major air pollutants due to the dominant usage of diesel fuel by commercial vehicles and buses. Hence, the study of the influence and the trends relating to these pollutants is extremely significant to the public health and the image of the city. The use of neural network techniques to predict trends relating to air pollutants is regarded as a reliable and cost-effective method for the task of prediction. The works reported here involve developing an improved neural network model that combines both the principal component analysis technique and the radial basis function network and forecasts pollutant tendencies based on a recorded database. Compared with general neural network models, the proposed model features a more simple network architecture, a faster training speed, and a more satisfactory prediction performance. The improved model was evaluated with hourly time series of RSP, NOx and NO2 concentrations monitored at the Mong Kok Roadside Gaseous Monitory Station in Hong Kong during the year 2000 and proved to be effective. The model developed is a potential tool for forecasting air quality parameters and is superior to traditional neural network methods.

Air Pollutants↗

Time-space modeling of journey-time exposure to traffic-related air pollution using GIS.

Journey-time exposures represent an important, though as yet little-studied, component of human exposure to traffic-related air pollution, potentially with important health effects. Methods for assessing journey-time exposures, either as part of epidemiological studies or for policy assessment, are, however, poorly developed. This paper describes the development and testing of a GIS-based system for modeling human journey-time exposures to traffic-related air pollution: STEMS (Space-Time Exposure Modeling System). The model integrates data on source activity, pollutant dispersion, and travel behavior to derive individual- or group-level exposure measures to atmospheric pollution. The model, which is designed to simulate exposures of people as they move through a changing air pollution field, was developed, validated, and trialed in Northampton, UK. The system currently uses ArcInfo to couple four separate submodels: a source activity/emission model (SATURN), a proprietary atmospheric dispersion model (ADMS-Urban), an empirically derived background air pollution model, and a purposely designed time-activity-based exposure model (TOTEM). This paper describes the structure of the modeling system; presents results of field calibration, validation, and sensitivity analysis; and illustrates the use of the model to analyze journey-time exposures of schoolchildren.

Air Pollution↗

The epidemiology and genetics of asthma risk associated with air pollution.

The occurrence of asthma and allergic diseases has continued to increase in the United States and worldwide, despite general improvements in air quality over the past 40 years. This observation has led many to question whether air quality is truly a significant risk factor in the development and exacerbation of asthma and whether further improvement in air quality is likely to result in improved health outcomes. However, epidemiologic studies have shown that levels of pollutants of less than the current ambient air quality standards still result in exacerbations of asthma and are associated with other morbidities as well. Specific locations, such as living near a roadway, might pose a special exposure risk. Genetic factors almost certainly play a role in determining susceptibility to pollutants, such as including those involved with antioxidant defenses. The best studied of these in the context of air pollution risks are glutathione-S-transferase polymorphisms. Irrespective of whether pollutants contribute to the development of asthma or the well-documented increases in asthma results in more people having pollutant-induced disease, poor air quality in many places remains a significant problem for patients with asthma and allergic disease. A number of public health, pharmaceutical, and nutriceutical interventions might mitigate the effects of pollutant exposure and deserve further study.

Air Pollution↗

Mapping hazard from urban non-point pollution: a screening model to support sustainable urban drainage planning.

Non-point sources of pollution are difficult to identify and control, and are one of the main reasons that urban rivers fail to reach the water quality objectives set for them. Whilst sustainable drainage systems (SuDS) are available to help combat this diffuse pollution, they are mostly installed in areas of new urban development. However, SuDS must also be installed in existing built areas if diffuse loadings are to be reduced. Advice on where best to locate SuDS within existing built areas is limited, hence a semi-distributed stochastic GIS-model was developed to map small-area basin-wide loadings of 18 key stormwater pollutants. Load maps are combined with information on surface water quality objectives to permit mapping of diffuse pollution hazard to beneficial uses of receiving waters. The model thus aids SuDS planning and strategic management of urban diffuse pollution. The identification of diffuse emission 'hot spots' within a water quality objectives framework is consistent with the 'combined' (risk assessment) approach to pollution control advocated by the EU Water Framework Directive.

Cities↗

Estimating the economic burden from illnesses associated with recreational coastal water pollution--a case study in Orange County, California.

A cost-of-illness framework was applied to health and income data to quantify the health burden from illnesses associated with exposure to polluted recreational marine waters. Using data on illness severity due to exposure to polluted coastal water and estimates of mean annual salaries and medical costs (adjusted to 2001 values) for residents of Orange County, California, we estimated that the economic burden per gastrointestinal illness (GI) amounts to 36.58 dollars, the burden per acute respiratory disease is 76.76 dollars, the burden per ear ailment is 37.86 dollars, and the burden per eye ailment is 27.31 dollars. These costs can become a substantial public health burden when millions of exposures per year to polluted coastal waters result in hundreds of thousands of illnesses. For example, exposures to polluted waters at Orange County's Newport and Huntington Beaches were estimated to generate an average of 36,778 GI episodes per year. At this GI illness rate, one can also expect that approximately 38,000 more illness episodes occurred per year of other types, including respiratory, eye, and ear infections. The combination of excess illnesses associated with coastal water pollution resulted in a cumulative public health burden of 3.3 million dollars per year for these two beaches. This paper introduces a public health cost variable that can be applied in cost-benefit analyses when evaluating pollution abatement strategies.

California↗