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PubMed2005

Exposure to ambient air pollution and prenatal and early childhood health effects.

Over the last years, concern for the possible influence of exposure to air pollutants in children during gestation or the first years of life has grown; exposure levels which may be reached nowadays in our dwellings and in our streets. In the present study evidence over the possible impact of ambient air pollution on the foetus and the infants (i.e.: less than 1 year) published during the last decade, 1994--2003, are revised. Studies on infant mortality and exposure to particles show an outstanding consistence in the magnitude of the effects, despite the different designs used. As a whole, data show that an increase in 10 microg/m3 of particle concentration (measured as PM10) is associated with to about 5% increase in post-neonatal mortality for all causes and around 22% for post-neonatal mortality for respiratory diseases. Regarding damage in foetal health, although results are not always consistent, most studies show associations with exposure to air pollution during pregnancy. However, the precise mechanisms of action of air pollutants on adverse reproductive results are still unknown, so is the period of exposure most relevant during pregnancy and the specific pollutant which may represent a higher risk. Follow-up studies evaluating personal exposure to different air pollutants are required, allowing for the adequate evaluation of the impact of each pollutant in different periods of pregnancy, as well as providing hypotheses on their possible mechanisms of action.

Air Pollutants↗
PubMed2005

Risk-based prioritization of air pollution monitoring using fuzzy synthetic evaluation technique.

Air pollution monitoring programs aim to monitor pollutants and their probable adverse effects at various locations over concerned area. Either sensitivity of receptors/location or concentration of pollutants is used for prioritizing the monitoring locations. The exposure-based approach prioritizes the monitoring locations based on population density and/or location sensitivity. The hazard-based approach prioritizes the monitoring locations using intensity (concentrations) of air pollutants at various locations. Exposure and hazard-based approaches focus on frequency (probability of occurrence) and potential hazard (consequence of damage), respectively. Adverse effects should be measured only if receptors are exposed to these air pollutants. The existing methods of monitoring location prioritization do not consider both factors (hazard and exposure) at a time. Towards this, a risk-based approach has been proposed which combines both factors: exposure frequency (probability of occurrence/exposure) and potential hazard (consequence). This paper discusses the use of fuzzy synthetic evaluation technique in risk computation and prioritization of air pollution monitoring locations. To demonstrate the application, common air pollutants like CO, NOX, PM10 and SOX are used as hazard parameters. Fuzzy evaluation matrices for hazard parameters are established for different locations in the area. Similarly, fuzzy evaluation matrices for exposure parameters: population density, location and population sensitivity are also developed. Subsequently, fuzzy risk is determined at these locations using fuzzy compositional rules. Finally, these locations are prioritized based on defuzzified risk (crisp value of risk, defined as risk score) and the five most important monitoring locations are identified (out of 35 potential locations). These locations differ from the existing monitoring locations.

Air Pollutants↗
PubMed2005

Emissions of particulate and gaseous pollutants within the Keelung Harbor region of Taiwan.

The Keelung port, which is located on the northern tip of Taiwan, right next to the Taipei metropolitan area, is an important international harbor. However, any air pollutants generated from the Keelung port region, immediately travel to the neighboring Keelung city, and greatly impact the residents' daily life and the quality of their environment. This study has investigated and quantified pollution emissions, from the Keelung port region, between 1997 and 2002. Emissions from major air pollution sources were estimated. The estimated results indicated that total TSP (total suspended particles) emissions had significantly increased, from 5221 ton/yr in 1997 to 262 687 ton/yr in 2002, due to the greatly increased volume of sand imported into Keelung Harbor. Quantities of other emissions, such as SO(2), NO(2), CO and HC remained stable and were 440, 207, 78 and 25 ton/yr, respectively, on average, with variations within 7% over the previous six-year period. By examining the emissions from pollution sources, it was found that TSP emissions mainly originated from re-suspension of dust, due to both vehicle movement and the sand unloading process; this accounted for over 99% of the total TSP emissions produced in the port region. About 80% of the total SO(2) emissions originated from the main ships' engines within the Keelung port region, due to the use of fuel with a high sulfur content. In addition, loading/unloading machines within the port region were the major sources of NO(2), CO and HC pollution emissions, which comprised 54, 58 and 66% of the total emissions of these pollutants, respectively. TSP emissions from Keelung port were much higher than from the neighboring Keelung city; hence, alleviating TSP emissions should be the first priority for air pollution reduction within both the port of Keelung and Keelung city.

Air Pollutants↗
PubMed2005

Biomonitoring of air pollution in a seasonally dry tropical suburban area using wheat transplants.

Air pollution has been identified as a serious problem throughout the world which causes tremendous loss to the crops by affecting plant growth and yield. Earlier, air pollution was restricted to urban and industrial regions. Over the last few decades, however, it has become evident that pollutants can be transported over long distances and hence their impact may be felt widely over rural areas. The present study was conducted to evaluate the impact of urban air pollution on suburban agriculture with respect to the changes in photosynthetic rate, stomatal conductance, water-use efficiency, plant height, numbers of tillers, leaves, ears and seeds, chlorophyll, carotenoid, protein, phenol, ascorbic acid, nitrogen and sulphate-sulphur contents and seed weight of pot-grown wheat plants (Triticum aestivum var. HUW 468) kept at different sites around Varanasi city receiving varying levels of pollution load. Mean concentrations of SO2, NO2 and O3 were monitored. The study clearly showed that plants are negatively affected by the ambient levels of air pollutants. Reduction in various parameters directly corresponded with the air pollution levels at different sites.

Agriculture↗
PubMed2006

Types of ectomycorrhiza as pollution stress indicators: case studies in Slovenia.

Mycorrhiza is the main spatial and temporal linkage between different constituents in a forest ecosystem. The functional compatibility and stress tolerance of ectomycorrhizal types is species specific, and therefore the information on the ectomycorrhizal community structure can add to the understanding of processes in forest ecosystems and can also be applied as tools for bioindication of pollution stress in forest soils. We have studied the effects of pollution (N and S) on trees and forest soils by: (1) quantification of ECM types diversity as in situ indicators in forest stands, (2) determination and quantification of pollution-sensitive or -insensitive ECM types as passive monitors, (3) root growth and development of ECM on nonmycorrhizal spruce seedlings, planted at the studied sites (active monitors), and (4) ECM infection (a bioassay based on mycorrhizal inoculum potential) of seedlings in an experimental set-up as ex situ testers. ECM species richness for Norway spruce trees (Picea abies) showed higher values in unpolluted sites than in polluted ones, while the differences were not significant for European beech trees (Fagus sylvatica). As pollution-sensitive or -insensitive ECM species in spruce forests, we suggest Hydnum rufescens (sensitive) and Paxillus involutus (unsensitive). Mycorrhizal potential in Norway spruce seedlings as a bioassay for soil N and S pollution was effective, and is suggested as an additional, standardized and widely comparable system in bioindication of soil pollution.

Environmental Monitoring↗
PubMed1993

Linking environmental and health care databases: assessing the health effects of environmental pollutants.

The assessment of pollutant effects on health status requires the mergence and analysis of two different databases: pollution measurements and health care information. This paper compares two subsets of these data: Ohio Environmental Protection Agency data on ambient air pollutants and Ohio Medicare data on respiratory diseases. Small area analysis was performed to assess statewide variations in hospital admission rates for respiratory diseases. The ambient air pollutant levels for each small area were compared to the variations in respiratory disease rates. Five groups of diseases correlated with pollutant levels. In addition, pollutant levels were significantly associated with medical complications. This study demonstrates the feasibility and benefit of linking environmental and health care databases and suggests the need for a more comprehensive, automated analysis of more pollutants and diseases.

Air Pollutants↗
PubMed1991

A case-control study of air pollution and tobacco smoking in lung cancer among women in Athens.

BACKGROUND: A case-control study exploring the role of smoking and outdoor air pollution in the causation of lung cancer, by histologic type, in nonsmoking women, was undertaken in Athens between 1987 and 1989. METHODS: One hundred one women with lung cancer and 89 comparison women with fractures or other orthopedic conditions, all permanent residents of Greater Athens, were included in the study. Smoking habits were ascertained through interviews, whereas lifetime exposure to air pollution was assessed by linking blindly lifelong residential and employment addresses of all subjects with objectively estimated or presumed air pollution levels. RESULTS: The age-adjusted relative risk and 95% confidence intervals for lung cancer among current smokers compared with nonsmokers was 3.40 (1.75-6.61); it was 7.43 (2.88-19.13) among those smoking for more than 30 years and 7.46 (2.40-23.17) among those smoking more than 20 cigarettes per day. The age-adjusted relative risk was 1.70 (0.75-3.89) for adenocarcinoma and 6.45 (2.73-15.25) for other histologic types of lung cancer; statistically significant dose-response trends were evident for both histologic groups. Air pollution levels were associated with increased risk for lung cancer but the relative risk was small and statistically not significant. However, when both air pollution and duration (or quantity) of tobacco smoking, as well as their interaction, were introduced in a multiple logistic regression model, the interaction term was significant at the suggestive level of 0.10. CONCLUSION: Whereas there is no effect of air pollution among nonsmokers, the relative risk contrasting extreme quartiles of air pollution among smokers of 30 years duration was 2.23. The interaction was almost exclusively accounted for by the nonadenocarcinoma lung tumors.

Aged↗
PubMed1991

Modifications of health behaviour in response to air pollution notifications in Copenhagen.

Ambient air quality is a major issue today in large cities all over the world. On the theoretical background of the health belief model and the health locus of control model, we studied the knowledge and beliefs about air pollution and the modifications of health behaviour brought about by information to the public about projected levels of air pollution, with special emphasis on reduction of outdoor activity and avoidance of car driving. Data were collected with a questionnaire among a sample of residents in the Copenhagen area. The respondents were almost universally knowledgeable about the prime emission source and concerned about the possible health effects of the air pollution in the area. Avoidance of outdoor activity was associated with personal experiences of symptoms ascribed to the air pollution, employment status, and with female sex, but not with knowledge or beliefs about the degree or health implications of the air pollution. The willingness to avoid car driving was positively associated with the belief that one can oneself influence one's health and with female sex. Lung diseased respondents were generally more prone to protect themselves than the healthy, both by avoiding outdoor activity and by being less willing to avoid car driving. The present study was conducted in an only moderately polluted city, and it is not clear whether the findings and conclusions can be generalized to more polluted cities. The study partly supported the underlying theories of the determinants of health behaviour, but also indicated a need for a broader theoretical framework, incorporating aspects of the respondents' life situation and personal experience which would be relevant to the specific type of health behaviour under study.

Adult↗
PubMed2006

Molecular biomarkers of oxidative stress in aquatic organisms in relation to toxic environmental pollutants.

The potential of oxygen free radicals and other reactive oxygen species (ROS) to damage tissues and cellular components, called oxidative stress, in biological systems has become a topic of significant interest for environmental toxicology studies. The balance between prooxidant endogenous and exogenous factors (i.e., environmental pollutants) and antioxidant defenses (enzymatic and nonenzymatic) in biological systems can be used to assess toxic effects under stressful environmental conditions, especially oxidative damage induced by different classes of chemical pollutants. The role of these antioxidant systems and their sensitivity can be of great importance in environmental toxicology studies. In the past decade, numerous studies on the effects of oxidative stress caused by some environmental pollutants in terrestrial and aquatic species were published. Increased numbers of agricultural and industrial chemicals are entering the aquatic environment and being taken up into tissues of aquatic organisms. Transition metals, polycyclic aromatic hydrocarbons, organochlorine and organophosphate pesticides, polychlorinated biphenyls, dioxins, and other xenobiotics play important roles in the mechanistic aspects of oxidative damage. Such a diverse array of pollutants stimulate a variety of toxicity mechanisms, such as oxidative damage to membrane lipids, DNA, and proteins and changes to antioxidant enzymes. Although there are considerable gaps in our knowledge of cellular damage, response mechanisms, repair processes, and disease etiology in biological systems, free radical reactions and the production of toxic ROS are known to be responsible for a variety of oxidative damages leading to adverse health effects and diseases. In the past decade, mammalian species were used as models for the study of molecular biomarkers of oxidative stress caused by environmental pollutants to elucidate the mechanisms underlying cellular oxidative damage and to study the adverse effects of some environmental pollutants with oxidative potential in chronic exposure and/or sublethal concentrations. This review summarizes current knowledge and advances in the understanding of such oxidative processes in biological systems. This knowledge is extended to specific applications in aquatic organisms because of their sensitivity to oxidative pollutants, their filtration capacity, and their potential for environmental toxicology studies.

Animals↗
PubMed2006

Determining when contamination is pollution - weight of evidence determinations for sediments and effluents.

Contamination is simply the presence of a substance where it should not be or at concentrations above background. Pollution is contamination that results in or can result in adverse biological effects to resident communities. All pollutants are contaminants, but not all contaminants are pollutants. Differentiating pollution from contamination cannot be done solely on the basis of chemical analyses because such analyses provide no information on bioavailability or on toxicity. Effects-based measures such as laboratory or field toxicity tests and measures of the status of resident, exposed communities provide key information, but cannot be used independently to determine pollution status. Laboratory studies can be predictive, but are rarely realistic. Measures of resident communities include innate natural variability and cannot easily distinguish between adaptation to contamination (a genetic process) and acclimation (a physiological process that may decrease energy reserves, possibly reducing such critical population-level parameters as reproduction). Finally, contaminant effects may not only be direct but also indirect; predicting such effects requires knowledge of the system under study as well as appropriate use of lines of evidence (LOE) such as toxicity tests directed to key species. Consequently, in sediments, effluents or other inputs/environmental compartments, determining when contamination is or may in future become pollution, requires a weight of evidence (WOE) assessment using different LOE appropriate to the situation under investigation. WOE investigations provide two different types of information: definitive conclusions regarding pollution; or, information as to what additional, investigative studies are necessary for definitive conclusions. Effectively, a WOE assessment comprises an initial screening-level ecological risk assessment (ERA), which may be followed by a detailed-level ERA if key uncertainties need to be resolved.

Geologic Sediments↗
PubMed2004

Effect of short-term exposure to low levels of gaseous pollutants on chronic obstructive pulmonary disease hospitalizations.

We examined the associations between gaseous pollutants and hospitalization for chronic obstructive pulmonary diseases (COPD) among elderly people living in Vancouver, British Columbia, Canada, a city in which ambient air pollution levels are relatively low. We regressed the logarithm of daily counts of acute COPD hospitalization during the 5-year period from 1994 to 1998 on the daily mean levels of each pollutant, after accounting for seasonal and subseasonal fluctuations, non-Poisson dispersion, and weather variables. Nitrogen dioxide and carbon monoxide were significantly associated with hospitalization for COPD, and the magnitude of effects was increased slightly with increasing days of exposure averaging, with the relative risk for a 7-day average being 1.11 (95%CI: 1.04, 1.20) and 1.08 (1.02, 1.13) for nitrogen dioxide and carbon monoxide, respectively. There was no significant association between either sulfur dioxide or ozone and COPD hospitalization. The combined relative risk for all four gaseous pollutants on COPD hospitalization was 1.21. The effects of gaseous pollutants on COPD hospitalization were not significant after adjustment for PM(10), although its inclusion did not have a marked effect on the point estimates for relative risks. Nitrogen dioxide has a significant impact on COPD hospitalization. Further studies are needed to separate the effects of single pollutants from the combined effects of the complex mixture of air pollutants in urban atmospheres.

Aged↗
PubMed2005

Genetic aspects of pulmonary responses to inhaled pollutants.

Air pollution continues to be a major public health concern in industrialized cities throughout the world. Recent population and epidemiological studies that have associated ozone and particulate exposures with morbidity and mortality outcomes underscore the important detrimental effects of these pollutants on the lung. Inter-individual variation in human responses to air pollutants suggests that some subpopulations are at increased risk to the detrimental effects of pollutant exposure, and it has become clear that genetic background is an important susceptibility factor. Environmental exposures to inhaled pollutants and genetic factors associated with disease risk likely interact in a complex fashion that varies from one population to another. The relationships between the genetic background and disease risk and severity is often evaluated through traditional family-based linkage studies and positional cloning techniques. Case-control studies based on association of disease or disease subphenotypes with candidate genes may have certain advantages over family pedigree studies, and have become useful for understanding complex disease phenotypes. This is based in part on continued development of quantitative analysis and development of mapping technologies. Linkage analyses with genetically standardized animal models are useful to identify genetic determinants of host responses to environmental stimuli. For example, linkage analyses using inbred mice have identified chromosomal segments (quantitative trait loci, QTL) that contain genes that control susceptibility to the lung inflammatory and immune dysfunction responses to ozone, nitrogen dioxide, zinc oxide, and sulfate-associated particles. Candidate genes within the pollutant susceptibility QTLs have been tested for proof-of-concept using gene-targeting and overexpression models. Importantly, significant homology exists between the human and mouse genomes. Therefore, comparative mapping between the human and mouse genomes should yield candidate susceptibility genes that may be tested by association studies in humans. The combined human studies and mouse modeling will provide important insight to understanding genetic factors that contribute to differential susceptibility to pollutants in human populations.

Air Pollutants↗
PubMed2005

Modelling of light pollution in suburban areas using remotely sensed imagery and GIS.

This paper describes a methodology for modelling light pollution using geographical information systems (GIS) and remote sensing (RS) technology. The proposed approach attempts to address the issue of environmental assessment in sensitive suburban areas. The modern way of life in developing countries is conductive to environmental degradation in urban and suburban areas. One specific parameter for this degradation is light pollution due to intense artificial night lighting. This paper aims to assess this parameter for the Athens metropolitan area, using modern analytical and data capturing technologies. For this purpose, night-time satellite images and analogue maps have been used in order to create the spatial database of the GIS for the study area. Using GIS advanced analytical functionality, visibility analysis was implemented. The outputs for this analysis are a series of maps reflecting direct and indirect light pollution around the city of Athens. Direct light pollution corresponds to optical contact with artificial night light sources, while indirect light pollution corresponds to optical contact with the sky glow above the city. Additionally, the assessment of light pollution in different periods allows for dynamic evaluation of the phenomenon. The case study demonstrates high levels of light pollution in Athens suburban areas and its increase over the last decade.

Air Pollutants↗
PubMed2025

Coupling of spectroscopy and nitrogen-oxygen isotopes unveils the mechanisms of dissolved organic matter and nitrate pollution in lakes within the agro-pastoral transition zone.

Lakes in arid and semi-arid regions are subjected to severe ecological stress, such as organic pollution, eutrophication, and salinization, due to climate change and human activities. This study investigates Chagannur Lake, a typical arid-region lake that is representative and ecologically sensitive in Northern China's agro-pastoral ecotone, to uncover its pollution characteristics and mechanisms. We employed fluorescence spectroscopy and stable isotope analysis to trace dissolved organic matter (DOM) and nitrate sources. The DOM composition was dominated by microbial metabolic byproducts and protein-like substances, suggesting that microbial processes are key to organic matter transformation. Source apportionment revealed that pollutants primarily originated from livestock and poultry manure (37.6 %), agricultural fertilizers (35.6 %), and soil erosion (24.7 %), with agricultural fertilizers contributing most significantly in the Gogstai River (63.3 %). A structural equation model (SEM) coupling spectral and mass spectrometric data revealed that microbial transformation significantly impairs the lake's self-purification capacity, thereby promoting pollutant accumulation (path coefficient = 0.91,*p < 0.05). Moreover, microbial processes link endogenous and exogenous pollution, a mechanism effectively traced by isotopic and fluorescence indices (path coefficient = 0.55, &#x204e;&#x204e;p < 0.01). These findings enhance the understanding of pollution sources and transformation mechanisms in arid-region lakes and offer foundational theoretical support for policymakers engaged in pollution control strategies.

Lakes↗
PubMed2005

Intake fractions of industrial air pollutants in China: estimation and application.

Intake fractions, an emissions-intake relationship for primary pollutants, are defined and are estimated in order to make simple estimates of health damages from air pollution. The sulfur dioxide (SO2) and total suspended particles (TSP) intake fractions for five cities of China are estimated for the four main polluting industries-electric power generation, mineral (mostly cement) products industry, chemical process industry and metallurgical industry (mainly iron and steel smelting). The Industrial Source Complex Long Term (ISTLT3) model is used to simulate the spatial distribution of incremental ambient concentrations due to emissions from a large sample of site-specific sources. Detailed population distribution information is used for each city. The average intake fractions within 50 km of these sources are 4.4x10(-6) for TSP, and 4.2x10(-6) for SO2, with standard deviations of 8.15x10(-6) and 9.16x10(-6), respectively. They vary over a wide range, from 10(-7) to 10(-5). Although the electric power generation has been the focus of much of the air pollution research in China, our results show that it has the lowest average intake fraction for a local range among the four industries, which highlights the importance of pollutant emissions from other industrial sources. Sensitivity analyses show how the intake fractions are affected by the source and pollutant characteristics, the most important parameter being the size of the domain. However, the intake fraction estimates are robust enough to be useful for evaluating the local impacts on human health of primary SO2 and TSP emissions. An application of intake fractions is given to demonstrate how this approach provides a rapid population risk estimate if the dose-response function is linear without threshold, and hence can help in prioritizing pollution control efforts.

Air Pollutants↗
PubMed2006

Attenuation of mining-derived pollutants in the hyporheic zone: a review.

Mine water pollution is a major cause of surface- and groundwater pollution in former mining districts throughout Europe. It is a potential barrier to achieving good status water bodies, which is a requirement of the EU Water Framework Directive. In the UK, a concerted effort has been made over the last decade or so to address the scientific and practical challenges relating to the remediation of mine water pollution. However, most of this work has focused on remediation of point sources of pollution (typically arising from abandoned mines and shafts), while the behaviour of mine water at the groundwater-surface water interface (the "hyporheic zone") has received far less attention in relevant scientific and engineering literature. The extent of mine water pollution and capacity for its attenuation at the hyporheic zone has not been well quantified while, furthermore, the complex chemical and microbial processes occurring there (specifically with reference to mining-derived pollutants) have not been investigated in any depth. The absence of such data may relate, in a large part, to the difficulty in physically measuring volumes and concentrations associated with these river inputs/exports. A far greater body of literature addresses biogeochemical processes at the hyporheic zone (especially relating to manganese), albeit many such articles relate to aqueous metal dynamics in general, rather than mine water specifically. This paper presents a review of the natural attenuation processes that may limit the movement and availability of mining-derived pollutants at the groundwater-surface water (GW-SW) interface, and specifically within the hyporheic zone. A substantial part focuses on precipitation and adsorption processes at the hyporheic zone, as well as discussing the role of microbial processes in governing metal ion mobility.

Adsorption↗
PubMed2006

Using satellite imagery for stormwater pollution management with Bayesian networks.

Urban stormwater runoff is the primary source of many pollutants to Santa Monica Bay, but its monitoring and modeling is inherently difficult and often requires land use information as an intermediate process. Many approaches have been developed to estimate stormwater pollutant loading from land use. This research investigates an alternative approach, which estimates stormwater pollutant loadings directly from satellite imagery. We proposed a Bayesian network approach to classify a Landsat ETM(+) image of the Marina del Rey area in the Santa Monica Bay watershed. Eight water quality parameters were examined, including: total suspended solids, chemical oxygen demand, nutrients, heavy metals, and oil and grease. The pollutant loads for each parameter were classified into six levels: very low, low, medium low, medium high, high, and very high. The results provided spatial estimates of each pollutant load as thematic maps from which the greatest pollutant loading areas were identified. These results may be useful in developing best management strategies for stormwater pollution at regional and global scales and in establishing total maximum daily loads in the watershed. The approach can also be used for areas without ground-survey land use data.

Bayes Theorem↗
PubMed2003

Urban air pollution induces micronuclei in peripheral erythrocytes of mice in vivo.

In this study, we explored the role of chronic exposure to urban air pollution in causing DNA damage (micronuclei frequency in peripheral erythrocytes) in rodents in vivo. Mice (n=20) were exposed to the urban atmosphere of São Paulo for 120 days (February to June 1999) and compared to animals (n=20) maintained in the countryside (Atibaia) for the same period. Daily levels of inhalable particles (PM10), CO, NO(2), and SO(2), were available for São Paulo. Occasional measurements of CO and O(3) were made in Atibaia, showing negligible levels of pollution in the area. The frequency of micronuclei (repeated-measures ANOVA) increased with aging, the highest values obtained for the 90th day of experiment (P<0.001). The exposure to urban air pollution elicited a significant (P=0.016) increase of micronuclei frequency, with no significant interaction with time of study. Associations (Spearman's correlation) between pollution levels of the week that precede blood sampling and micronuclei counts were observed in São Paulo. The associations between micronuclei counts and air pollution were particularly strong for pollutants associated with automotive emissions, such as CO (P=0.037), NO(2) (P<0.001), and PM10 (P<0.001). Our results support the concept that urban levels of air pollution may cause somatic mutations.

Administration, Inhalation↗