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PubMed2026

Indoor Air Quality (IAQ) analysis and 16S rRNA gene sequencing of indoor air pollutants in a 3000-capacity religious auditorium.

A thorough molecular and environmental evaluation of microbial isolates and indoor air quality (IAQ) at a place of worship is presented in this work. The study used a dual-methodological approach, including systematic environmental monitoring to assess occupant health concerns and 16S rRNA gene sequencing for taxonomic identification. Four different bacterial isolates were successfully identified by molecular analysis using BLAST and phylogenetic reconstruction: Bacillus tropicus (A11), Leclercia adecarboxylata (A12), Acinetobacter sp. (A13), and Escherichia coli (A14). The evolutionary position of isolate A13 indicated possible horizontal gene transfer, underscoring the existence of flexible, opportunistic pathogens within the indoor environment, whereas isolates A11 and A14 demonstrated significant genetic stability. Concurrently, six sessions of air quality monitoring showed a thermally demanding environment, with humidity (56.00-70.51%) and temperatures (29.21-33.79 °C) continuously surpassing ASHRAE guidelines. The average pollutant concentrations are within WHO and USEPA safety criteria, however, there were outliers that may suggest sporadic pollutant penetration (outdoor) or resuspension of dust. The results demonstrate a clear relationship between increased chemical pollutants (TVOCs) and reduced thermal comfort. To reduce the congregation's acute respiratory and cardiovascular risks, optimal ventilation systems and source-control measures are urgently needed, as evidenced by the presence of clinically relevant microorganisms combined with dangerous pollution levels.

Analysis↗
PubMed2004

Exposures and health outcomes from outdoor air pollutants in China.

China's economy has developed rapidly in the recent two decades. Economic development is usually linked with increase in energy consumption and consumption emissions, which in turn leads to worsening of air quality. Due to the adoption of various control measures, the ambient air quality in a number of large cities in China has actually improved. The ambient air TSP and SO(2) levels in China have been decreasing in the last decade. However, ambient air NO(x) level has been increasing due to the increased number of motor vehicles. Coal has been and is still the major source of energy in China. Ambient air pollution in large cities has changed from the conventional coal combustion type to the mixed coal combustion/motor vehicle emission type. A series of epidemiological studies on air pollution and health effects ranging from mortality, morbidity to functional changes have been conducted in China. The results showed that ambient air pollution had acute and chronic effects on mortality, morbidity, hospital admissions, clinical symptoms, lung function changes, etc. The exposure-response relationship between air pollutants and daily mortality, morbidity, hospital admissions, and lung function has been established accordingly.

Adult↗
PubMed2003

The role of air pollution in the relationship between a heat stress index and human mortality in Toronto.

In this study we considered confounding from air pollutants and chronological variables in the relation between humidex, a summer temperature and humidity index, and nonaccidental mortality, from 1980-1996 in Toronto, Canada. Changes in the risk of death by age group, gender, and combined cardiac-respiratory cause of death were estimated for both 1 degree C and 50-95th percentile increases in humidex using a generalized additive linear model. With air pollution terms in the models, relative risk (RR) point estimates narrowly exceeded 1.0 for all groups. Humidex effects were most apparent for females (RR=1.006, 95% CI=1.004-1.008 per 1 degree C humidex and RR=1.089, 95% CI=1.058-1.121 for 50th to 95th percentile humidex). When air pollution was omitted from the model, RR in the 50-95th percentile analysis increased less than 1.71% for all groups except females, for which RR decreased 1.42%. Differences in RR per 1 degree C humidex were all less than 0.12%. Confidence intervals narrowed slightly for all groups investigated. Heat stress has a statistically significant, yet minimal impact on Toronto populations, and air pollution does appear to have a small, but consistent confounding effect on humidex effect estimates.

Age Factors↗
PubMed2004

Difference in the relation between daily mortality and air pollution among elderly and all-ages populations in southwestern France.

Numerous time series studies around the world have reported an association between mortality and particulate air pollution. We investigated the distribution over time of effect of air pollution on short-term mortality among subjects aged 65 years and older and of all ages in Bordeaux, France. Statistical analysis was based on generalized additive models using either loess or penalized spline smoothing. Our study found a significant positive association between air pollution and all nonaccidental mortality and specific mortality in both group of population (all ages and elderly) with a greater effect among the elderly, particularly for respiratory mortality. For this case, we observed a greater effect according to distributed lag models (0-5 days) among the elderly, with an estimated increase of 9.2% in the daily number of deaths for 10 microg/m(3) of daily black smoke [95% CI, 3.4-15.3]. These results contribute to the efforts made to understand how air pollution promotes adverse health effects and to identify susceptible subgroups.

Aged↗
PubMed1990

An ecological study on air pollution: changes in annual ring growth of the Japanese cedar and prevalence of respiratory symptoms in schoolchildren in Japanese rural districts.

The effect of air pollution caused by oil-fired electricity-generating stations on the annual ring growth of the Japanese cedar (Cryptomeria japonica, D. Don) and prevalence of respiratory symptoms in schoolchildren were investigated. By retrospective analysis the annual ring growth has been demonstrated to show good agreement with the general trend in air pollution. In addition it was found to be related to the prevalence of respiratory symptoms. The reduction in annual ring growth and increase in the prevalence of respiratory symptoms followed a deterioration in air pollution. Following upgrading of the power station and an improvement in air pollution, the annual ring growth and prevalence of respiratory symptoms showed opposite changes, respectively. Concerning the latter, the prevalence of wheezing and respiratory symptoms associated with school absence in schoolchildren with a positive skin test to house dust extract showed a closer correlation with the annual ring growth when compared with those who had never had a positive skin test.

Adolescent↗
PubMed1987

Time trends of tobacco smoking, air pollution, and lung cancer in Athens.

Athens is a city with a serious air pollution problem which has existed for more than 20 years. To evaluate whether air pollution has affected lung cancer incidence (and hence, mortality) in the population of Athens we have compared standardized lung mortality between Athens and the rest of Greece taking into account the tobacco consumption trends in the respective populations and varying the postulated latency between 0 and 20 years. There is no evidence for an independent or interactive (with tobacco smoking) effect of air pollution on lung cancer mortality; the tobacco-adjusted mortality appears, if anything, lower in Athens than in the rest of Greece and the slopes of lung cancer mortality on tobacco consumption are almost identical in Athens and in the rest of Greece. By contrast, the same data are compatible with a strong effect of tobacco smoking on lung cancer mortality, an effect which appears to involve not only the early carcinogenic stages but also some of the later ones. The results of the present analysis do not support the hypothesis that air pollution, at least in Athens until 1980, has increased the incidence of lung cancer to an extent large enough to be detectable in ecological correlation analyses. Nevertheless the inherent limitations of these methods indicate that their results should be interpreted with caution and only as a step toward the gradual understanding of a complex issue.

Air Pollution↗
PubMed1998

Biodiversity of parasites in a freshwater environment with respect to pollution: metazoan parasites of chub (Leuciscus cephalus L.) as a model for statistical evaluation.

This paper represents an attempt to evaluate the environmental indicative potential of the biodiversity of monogenean parasites using hierarchically structured species-abundance data. A logical set of statistical methods integrating standard diversity indices, a novel approach to quantitative analysis of cumulative species-abundance curves and species-abundance models was applied for this purpose. Applicability of biodiversity measures was demonstrated using experimental data from a 1-year study on the ecology of metazoan parasites of chub (Leuciscus cephalus) in one polluted and one control site in the Morava river, Czech Republic. Analyses at the component community level revealed a significant decrease in the number of parasite species with a more equal distribution of their abundances in the polluted site compared with the control site. In order to reach a better understanding of the changes, diversity of Monogenea as a dominant part of the community was further examined within categories of species created according to: (1) specificity of infection (specialists and generalists), (2) monogenean genera (Dactylogyrus, Gyrodactylus and Paradiplozoon) and (3) inhabited guilds (skin + fins, gills). Assemblages of specialists in the polluted site exhibited a significantly reduced species richness and unequal distribution of abundances. The opposite pattern was observed in the case of generalists. The influence of pollution was also reflected by the distribution of species abundances within communities of Dactylogyrus and Paradiplozoon, while no significant shift was identified in the genus Gyrodactylus.

Animals↗
PubMed2001

Scavenging of thorium isotopes in the Arctic regions: implications for the fate of particle-reactive pollutants.

The sources of inorganic pollutants to the Arctic areas are reviewed using previously published results. The removal of particle-reactive pollutants is discussed using thorium scavenging as an analog. The scavenging of 234Th from the upper water column (approximately 100 m) and sediment inventory of 230Th from the deep Arctic waters is compared to different ocean basins in the subarctic areas. Such a comparison shows that 234Th is in equilibrium with its parent, 238U, in certain regions of the Canada Basin of the Arctic Ocean, while it is deficient in other regions of the arctic as well as in sub-polar ocean basins. This implies that the particle-reactive pollutants in the deep Arctic of the Canada Basin are less likely to be removed from the deep waters and will eventually be transported out of this area. We have utilized the 230Th inventory in sediments from the Arctic area to determine the removal rates of particle-reactive nuclides. The 230Th inventory in the deep Arctic Ocean of the Canada Basin is much lower than the Norwegian Sea and the Fram Strait of the Arctic as well as all other sub-polar world oceans. These observations suggest that any pollutants into the deep Arctic areas of the Canada Basin are less likely to be removed locally and may be transported out of this area. In those areas, the colloidal material could potentially play a major role in the removal of particle-reactive contaminants.

Arctic Regions↗
PubMed2003

[Short-term relationship between air pollution and mortality in 13 Spanish cities].

BACKGROUND AND OBJECTIVE: EMECAM is a collaborative project that seeks to evaluate the short-term effects of air pollution on mortality in Spain. MATERIAL AND METHOD: We collected data for air pollutants (particles and gases), daily mortality (total except external, cardiovascular and respiratory causes) and co-variables (temperature, humidity, influenza and calendar variables) in 13 Spanish cities. The magnitude of the association in every city was estimated using GAM under a Poisson distribution. Combined estimates for each cause and pollutant were obtained under 'fixed effects' and 'random effects'models. RESULTS: An increase of 10 (g/m3 in the levels of the average of the concurrent and one day lag for black smoke was associated with a 0.8% (CI: 0.4-1.1) increase in mortality. The same increase in the concentration of SO2 was associated with a 0.5% (CI: 0.1-1.0) increase in daily deaths, and a 0.6% (CI: 0.3-0.8) increase in the case of NO2. An increase of 1 mg/m3 in the levels of CO was associated with an increase of 1.5% (CI: 0.5-2.6) in daily deaths. CONCLUSIONS: There is a short-term association between increases of daily levels of air pollutants and the number of daily deaths in Spanish cities.

Air Pollution↗
PubMed2001

Potential of freezing in wastewater treatment: soluble pollutant applications.

When wastewater containing only soluble pollutants is frozen gradually, ice crystals grow from the pure water only, while pollutants are rejected into the liquid phase thus increasing their concentration. In this way, pure water can be removed from various wastewaters. Two kinds of wastewater were studied: synthetic wastewater containing water and one or more soluble pollutants, and industrial wastewaters (urban wastewater and cutting oil wastewater). In most cases, separation efficiency close to 100% was achieved. A large range of pollutant concentrations was studied in order to determine the limits of freezing separation.

Freezing↗
PubMed2003

Application of a rapid method for identifying fecal pollution sources in a multi-use estuary.

We demonstrate the application of a new PCR assay to detect and differentiate human and ruminant sources of fecal pollution in natural water samples. We tested samples collected from Tillamook Bay, Oregon, which has a long history of fecal pollution levels that exceed acceptable standards. The most likely sources are from dairy operations and ineffective sewage treatment. Using a suite of three PCR primer pairs specific for human or ruminant bacterial 16S ribosomal DNA markers, we detected at least one marker in 17 of 22 samples. In general, host-specific fecal markers were detected in areas that are heavily impacted by anthropogenic activities. Nine out of 11 sites classified as either urban or near a sewage point source were positive for the human marker while only five of these same sites were positive for ruminant markers. Conversely, 12 out of 21 sites classified as rural or agricultural use were positive for ruminant markers, while only six of these sites were positive for human pollution. This suite of host-specific genetic markers holds promise for identifying non-point source fecal pollution in coastal waters.

Agriculture↗
PubMed2003

Study of heavy metal pollution and speciation in Buyak Menderes and Gediz river sediments.

In this study, two economically important rivers of Turkey, Gediz and Buyuk Menderes (BM) are studied to determine their environmental pollution levels. An old analytical procedure involving sequential chemical extraction is improved and used for the partitioning of particulate trace metals (Cu, Co, Cr, Mn, Fe, Zn, Pb and Ni). Cationic and anionic Mn and Cr species with different phases are also determined by using leaching, extraction and ion exchange speciation processes. The sediment samples are analysed using graphic-furnace atomic absorption spectroscopy and differential pulse anodic stripping voltameter. Experimental results obtained on five replicate samples of fluvial bottom surface sediments at the sampling points demonstrate that the relative standard deviation of the sequential extraction procedure is generally better than +/-10%. The accuracy, determined by comparing total metal concentrations with the sum of the five sequential chemical extractions, is proved to be satisfactory. The detection limits established for three standard deviations of blank for different metals are identical and found to be 0.1mg/kg for sediment samples and 1 ppb for water samples. The results show that the pollution levels are significant especially for Pb, Cr, Mn and Zn in the Gediz river and Co, Mn, and Zn in the BM river. Comparison between our results and the measurements outlined before industrialization and the beginning of the intensive pesticide applications in agricultural fields (In: Broekaert et al., editors, Metal speciation in the environment, vol. 23. 1989. p. 601-11; A research on the environmental pollution in the agricultural fields and watering in the Aegean region, Ege University Research Project, No. 127 1988 (in Turkish); DSI Water Analyses Report, Ankara, 1985 (in Turkish)) show that the pollution in these rivers is probably originated from industrial, agricultural and domestic waste discharges.

Environmental Monitoring↗
PubMed2003

Photocatalytic degradation of aqueous pollutants using silica-modified TiO(2).

Photocatalytic degradation (PCD) of several aqueous pollutants was investigated using a porous silica-coated titanium dioxide (SiO(2)-TiO(2)) photocatalyst. Several cationic, neutral and anionic pollutants were tested. The results indicate that modifying the surface properties of TiO(2) using silica significantly enhances the PCD rate of the cationic pollutants. The rate enhancement decreased with an increase in substrate concentration, especially for the quaternary amines, and was attributed to the decrease in initial adsorption. However, no significant rate-increase resulted for acetate and phenol. Results suggest that the increased presence of cationic pollutants at the catalyst surface caused the rate enhancement.

Adsorption↗
PubMed2002

A mathematical algorithm to identify toxicity and prioritize pollutants in field sediments.

In order to evaluate sediment toxicity, a mathematical algorithm was developed to compute the toxicity of multiple component mixtures acting in an additive manner. A statistical approach was devised to determine the presence of potential interactive effects among mixture components. The algorithm uses three kinds of data to obtain an integrative approach to sediment toxicity assessment: Microtox toxicity data (EC50 values), sediment pollutant concentration measurements, and sequential extraction (SEQ) data to investigate metal partitioning. To simplify the analysis of complex mixtures using a prioritization scheme based on intrinsic toxicity and relative abundance, a toxicity index (TI) was employed as an indicator of adverse ecological impact. In general, the ranking of contaminants using the TI approach was found to be most efficient in reducing computational time, and concentrations using bioavailability data from SEQ was found to be the best theoretical predictor of the experimental mixture toxicity value. Only a few pollutants that were present at the greatest abundance were needed to provide a good approximation of the calculated EC50 found when all components were included. Not only does this substantially reduce the computational time needed to determine the EC50, it could in some cases dramatically reduce the pollutant monitoring effort required to track toxicity effectively. This approach would have substantial implications for both risk assessment and for remediation strategies, making them more efficient by focusing on the priority pollutants identified.

Algorithms↗
PubMed2003

Ecological risk assessment of pollutant chemicals: extinction risk based on population-level effects.

The extinction probability is one of the most useful endpoints that are utilized in conservation biology. A parallel approach is advocated for the ecological risk assessment of chemical pollutants. The presented framework estimates extinction probability induced by pollutant chemicals in order to evaluate ecological hazards of pollution, and is applicable to any biological community (aquatic or terrestrial). The analytical framework, which is based on stochastic population dynamics theory, is briefly explained. The extinction risk estimation is feasible if ecotoxicological data concerning pollutant effects on population growth rate of organisms (the intrinsic rate of natural increase), and if environmental exposure concentration is provided. Tentative risk estimation was made for some agrochemicals and surfactants on zooplankton populations (Daphnia) as target organisms.

Agriculture↗
PubMed2003

Simulation of transboundary pollutant transport action in the Pearl River delta.

The rapid economic development in The Pearl River delta region (PRDR) has exerted serious potential pollution threats to areas in the vicinity, which have complicated the task of environmental protection in Hong Kong and Macau. In this paper, a three-dimensional numerical pollutant transport model coupled with a synchronised numerical hydrodynamic model, is developed and employed to simulate the unsteady transport of a representative water quality variable chemical oxygen demand in The Pearl River Estuary. It is demonstrated that there exists a transboundary pollutant transport action between Guangdong Province and Hong Kong for the pollutants in the wastewater discharged from PRDR.

China↗
PubMed1998

DNA fingerprinting analysis by a PCR based method for monitoring the genotoxic effects of heavy metals pollution.

Environmental pollutants can have deleterious effects on living organisms. At high concentrations, or at high activities, they can cause acute toxicity damaging cells, tissues and organs. Chronic toxification, on the other hand, can also cause serious damage from bio-accumulation. Plants, as biological indicators, can measure both the actual and the potential effects of pollutants, when they are used to measure effects of heavy metals. We have applied a system of "molecular fingerprinting" based on PCR (RAPD: Random Amplified Polymorphic DNA) to the evaluation of the genotoxic effects of heavy metals in order to estimate the environmental risk connected with their potential mutagenic effects in the model plant Arabidopsis thaliana, ecotype Columbia. Genomic DNA was utilised for RAPD analysis using random primers (10-mers). DNA from plants exposed to heavy metals solution displayed polymorphic bands which were not detectable in DNA of unexposed plants. The enhanced formation of RAPD polymorphisms was also observed in DNA of plant exposed in situ to an industrial pollution source. The comparison between "unexposed" and "exposed" genomes show that RAPD analysis can be used to evaluate how the environmental pollutants modify the structure of DNA in living organisms.

Biosensing Techniques↗
PubMed2000

The application of reporter gene assays for the determination of the toxic potency of diffuse air pollution.

Diffuse air pollution consists of a mixture of numerous compounds. It is emitted by many distributed sources and is omnipresent due to atmospheric transport. Risk assessment of the complex mixture of air pollutants on the basis of the toxicity of the individual compounds is not yet possible because the chemical identity and/or toxicity of the constituencies of a substantial fraction is unknown. In addition, no adequate procedures are available to integrate toxicity data of such complex mixtures, so that an individual risk assessment of the constituents of air pollution disregards possible combination effects. In the present study, an approach has been developed to assess the toxic potency by using in vitro bio-assay techniques. Genotoxicity was assessed in the umu-assay, a reporter gene assay using a strain of Salmonella typhimurium stably transfected with a plasmid (pSK1002) carrying the SOS-gene umuC fused to the reporter gene lacZ. Arylhydrocarbon-receptor activation was assessed in the DR-CALUX-assay, using a stably transfected H4IIE hepatoma cell line containing a plasmid for the luciferase gene under transcriptional control of dioxin-responsive elements. Samples of airborne particulate matter (APM) were collected with a high volume sampler next to a highway and in a natural conservation area. Both assays proved to be applicable to quantify genotoxicity and the presence of polycyclic aromatic hydrocarbons (PAHs) in small extracts from air-filter samples. Results indicate that PAHs from traffic exhausts seem to be largely responsible for an increased genotoxic activity of APM collected down-wind from the highway (western wind). APM collected at eastern wind directions seems to have a different composition of compounds, with a higher genotoxic activity that is less related to highway-emitted PAH-like compounds. At northern wind directions, APM is relatively less genotoxic and contains less PAHs than at other wind directions. Dioxin-like compounds contribute negligibly to the Ah-receptor agonistic potency of APM. Airborne pollutants with genotoxic and/or PAH-like characteristics form an undesired mutagenic risk, which will be evaluated in further in vivo studies.

Air Pollutants↗