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PubMed2001

Role of urbanization and air pollution in adolescent asthma: a mass screening in Taiwan.

BACKGROUND AND PURPOSE: The prevalence of asthma in school children in Taiwan is increasing. This study used mass screening among middle school children in Taiwan to determine the prevalence of asthma and related factors. METHODS: Data were collected from parents using a self-reported questionnaire and from children using the International Study of Asthma and Allergies in Childhood (ISAAC) video questionnaire. Six study teams conducted the survey nationwide in 1995-1996, with the assistance of middle school nurses and teachers. RESULTS: Among the 1,018,031 students at 795 middle schools who returned questionnaires, 8.5% had a history of asthma (ranging in prevalence from 4.2% to 13% in 25 areas). The prevalence of asthma was higher in boys than in girls (10.0% vs 7%) and was highest in more urbanized areas (11.2%), followed by moderately urbanized areas (7.4%) and less urbanized and rural areas (6.5%). Controlling for age, family smoking, family incense burning, and parental education level, multivariate logistic regression models indicated that children living in an area with heavy air pollution were more likely to have asthma than those in an area with no or light pollution (odds ratio, OR = 2.01 and 95% confidence interval, CI = 1.94-2.09 based on parental ranking of pollution level, or OR = 1.30 and 95% CI = 1.18-1.42 based on pollution level reported by the Environmental Protection Administration). CONCLUSIONS: Adolescent asthma in Taiwan is most prevalent in the most urbanized areas and decreases in prevalence in less urbanized areas. This study also found that higher parental education level and higher area air pollution were associated with higher adolescent asthma prevalence.

Adolescent↗
PubMed2001

Atopy prevalence and spirometric performance in asymptomatic schoolchildren exposed to air pollution.

The association between respiratory disease and high levels of air pollution is well known. The most common risk factors associated with lung function decrease are air-borne particulates, ozone (O3), nitrogen dioxide (NO2) and sulphur dioxide (SO2). The aim of our study was to evaluate any difference in the prevalence of atopy and any possible early impairment in lung function in two groups of children exposed to different levels of air pollution. We studied 220 children in two cities in northern Italy: Milan (107 children), considered a metropolitan area with a high level of air pollution, and Erba (113 children), a small town, close to Lake Como, considered a rural area with a low level of air pollution. All subjects underwent respiratory function tests and skin-prick tests for the main inhalatory allergens. Parents were requested to fill in a questionnaire about parents' smoking habits and subjective evaluation of local motor traffic intensity. Aerobiological surveys showed a significantly higher grass pollen concentration in Erba than in Milan in the study year and in the three previous years. Schoolchildren in Milan and Erba showed similar pulmonary function results, except for forced expiratory flow at 75% of forced vital capacity (FEF75) values that, while within the range of normality, were significantly lower in Milan than in Erba. A high incidence of atopy was evident in both groups: 45% among the children living in Erba and 35% among those in Milan; skin-prick-test positivity for grass-pollen was statistically more frequent in Erba than in Milan. No evidence of a link between atopy and FEF75 reduction emerged, nor between FEF75 reduction and exposure to passive smoke. The association between FEF75 reduction and chronic high levels of air pollution is appealing, but further confirmation studies are necessary.

Air Pollutants↗
PubMed2001

Application of a constructed wetland for non-point source pollution control.

In Taiwan, non-point source (NPS) pollution is one of the major causes of impairment of surface waters. The main objective of this study was to evaluate the efficacy of using constructed wetlands on NPS pollutant removal and water quality improvements. A field-scale constructed wetland system was built inside the campus of National Sun Yat-Sen University (located in southern Taiwan) to remove (1) NPS pollutants due to the stormwater runoff, and (2) part of the untreated wastewater from school drains. The constructed wetland was 40 m (L) x 30 m (W) x 1 m (D), which received approximately 85 m3 per day of untreated wastewater from school drainage pipes. The plants grown on the wetland included floating (Pistia stratiotes L.) and emergent (Phragmites communis L.) species. One major storm event and baseline water quality samples were analyzed during the monitoring period. Analytical results indicate that the constructed wetland removed a significant amount of NPS pollutants and wastewater constituents. More than 88% of nitrogen, 81% of chemical oxygen demand (COD), 85% of heavy metals, and 60% of the total suspended solids (TSS) caused by the storm runoff were removed by the wetland system before discharging. Results from this study may be applied to the design of constructed wetlands for NPS pollution control and water quality improvement.

Ecosystem↗
PubMed2002

[Traffic-related air pollution at the place of residence and risk of cancer among children].

INTRODUCTION: The hypothesis that exposure to traffic-related air pollution increases the risk of cancer developing during childhood was investigated. MATERIALS AND METHODS: We enrolled 1,989 children notified to the Danish Cancer Registry with a diagnosis of leukaemia, tumour of the central nervous system (CNS), or malignant lymphoma during 1968-1991, and 5,506 control children selected at random from the entire childhood population. The residential histories of the children were traced from nine months before birth up to the time of diagnosis, as was a similar period for the controls. Information on traffic and the configuration of streets and buildings was collected for each of the 18,440 identified addresses. Concentrations of benzene and nitrogen dioxide (indicators of traffic-related air pollution) were calculated for the relevant residential periods, and combined into exposures to air pollution during pregnancy and childhood, respectively. RESULTS: The risks of leukaemia, CNS tumours, and all selected cancers combined were not related to exposure to benzene or nitrogen dioxide during either period. The risk of lymphomas increased by 25% (p for trend = 0.06) and 51% (p for trend = 0.05) for a doubling of the concentration of benzene and nitrogen dioxide, respectively, during the pregnancy. The association was restricted to Hodgkin's disease. DISCUSSION: On the basis of a low potential for selection bias, information bias, and confounding factors, we conclude that traffic-related air pollution at the residence of children is not linked to the risk of leukaemia or CNS tumour, which are the two major types of childhood cancer. The results indicated a possible association between air pollution and the risk of Hodgkin's disease, but the evidence allows of no firm conclusion at present.

Adolescent↗
PubMed2002

Pollution control of industrial wastewater from soap and oil industries: a case study.

Industrial wastewater from soap and oil industries represents a heavy pollution source on their receiving water body. This paper studies a case of pollution control at Tanta Soap and Oil Company, Banha Factory, Egypt. The factory production includes soap, edible oil, and animal fodder. About 4,347 m3/day of industrial wastewater effluent was discharged via gravity sewers to the public sewerage system. Most of the effluent was cooling water because the cooling process in the factory was open circle. In spite of the huge quantity of cooling water being disposed of, disposal of wastewater was violating pertinent legislation. Three procedures were used for controlling the pollution at the Banha Factory. Firstly, all open circuit cooling systems were converted to closed circuit thus reducing the quantity of the discharged wastewater down to 767 m3/day. Secondly, the heavily polluted oil and grease (O&G) wastewater from the refinery unit is treated via two gravity oil separator (GOS) units, dissolved air floatation (DAF), and biological units in order to reduce the high levels of O&G, BOD, COD, and SS to the allowable limits. Thirdly, the heavily polluted waste effluent from the 'red water' saponification unit is treated separately by acidification to convert the emulsified fatty acid to free form in order to be separated through an oil separation unit. The effluent is then passed to liming stage to neutralize excess acidity and precipitate some of the dissolved matters. The mixture is finally clarified and the pH is adjusted to the allowable limits. The effluent wastewater from the three processes is collected and mixed in a final equalization tank for discharging effluent to the public sewerage system. The characteristics of the effluent water are very good with respect to the allowable Egyptian limits for discharging effluent to the public sewerage system.

Bioreactors↗
PubMed2002

[The role of environmental and epidemiological surveys of ambient pollution in the evaluation of a risk for "acute" mortality].

The paper provides evidence that there is a relationship of daily death rates to variations in the concentrations of total dust and some gaseous ambient pollutants. The great advantage of a procedure to analyze temporary variables is that it makes it possible to retrospectively use the available materials of routine monitoring of air pollution and to consider these effects (cases of death in particular). Along with the high informative value of environmental and epidemiological surveys (EES) based on the analysis of time series, this advantage allows one to recommend them for widely use within the sociohygienic monitoring system. At the same time the paper shows it necessary to control the quality of available data and to chose monitoring centers comparable in this regard. Inevitable missing data on the concentrations of different pollutants on days off and on some working days are of particular value under the actual conditions of monitoring of air pollution. The approach applied in this study to the choice of the most effective ways of filling of such gaps may be recommended. Nevertheless, incomplete data and the need for their artificial reproduction should be regarded as a source of uncertainty of specific results of EES of this type. Increments in mortality rates for a certain increase in the concentrations of pollutants may be used in the risk assessment projects when a dose-response relationship is analyzed. The larger number of EES based on the analysis of time series will be conducted in the regions of Russia, the more reliable the use of EES-grounded single risks will be at the regional and federal level.

Air Pollutants↗
PubMed1975

Prevalence of respiratory symptoms in towns with different air pollution.

An epidemiologic study was carried out for the estimation of air pollution as a risk factor for chronic obstructive lung disease. The whole male population aged 40 to 60 years was investigated in a polluted and a non-polluted control town. The subjects with occupational exposure to dusts, gases and irritant vapours were discarded from the study. The prevalence of respiratory symptoms and of chronic bronchitis in the polluted town was twice that in the control (non-polluted) one. These results are discussed in the light of some previous investigations of the authors and of the available data in the literature.

Adult↗
PubMed2003

[Evaluation of pollution load in marine coastal waters].

The potential pollution loads, of both organic and eutrophicating type, along the Italian coast were evaluated with reference to census data of 1991. The methodology adopted for the indirect evaluation of loads are those developed by the Water Research Institute of the Italian National Research Council. They take into account the different sources of pollution load, namely population, industry, agriculture and cattle farming. Pollution loads were estimated at coastal provinces level. Annual riverine fluxes of pollutants were also evaluated for the main Italian rivers. Finally, the positive role played by the adoption of monitoring plans forecasted by the national law recently come into force (DL.vo 152/99) for a better evaluation of the pollution loads was stressed.

Italy↗
PubMed2003

[Soil pollution of Cu, Zn, Pb and Cd in different city zones of Nanjing].

The Nanjing city was divided into six zones as smelter industry, inner commercial, inner residence, newly developed, urban greenland and preserved scenic. In each zone, soil samples were randomly collected by triple subsampling technique. Total 56 soil samples were digested by mixed solution of nitric, chloridic and sulphatic acids and by sequential extractants respectively according to the standard methods. The total and fractional heavy metals were determined by AAS. The mean total content of Pb, Cu, Zn and Cd of the soils from smelter industry, inner commercial, inner residence, newly developed, urban greenland and preserved scenic zone was 117.1 +/- 103.7 mg.kg-1, 39.86 +/- 39.9 mg.kg-1, 273.3 +/- 131.6 mg.kg-1 and 1.13 +/- 0.7 mg.kg-1, with the overall pollution index being 5.4, 4.9, 3.4, 1.6, 2.4 and 2.3 respectively. The pollution in the smelter industrial zone was characterized by high concentration but low chemical mobility of Pb and Cd, while that in inner cities by high concentration of lead and zinc with quite larger acelatic acid extractable pool. Except for the soils from newly developed and preserved zones, the heavy metals were more or less superficial in respect to their depth distribution in the urban soils. The dramatic soil pollution of Pb and Cd in the urban area might cause any health risks for children, whose activities are believed to happen in a relative limited area. The future research on urban soil pollution should pursue the effect of soil pollution on human environment in the urban area.

Cadmium↗
PubMed1992

[The effect of atmospheric pollution in the city of Srednogorie on the health of the population].

The town of Srednogorie is one of the ecologically endangered districts of Bulgaria because of environmental pollution by the copper works. The morbidity of the population is studied in relation to the atmospheric air pollution. Basic pollutants are: sulphuric compounds (sulphur dioxide and sulphuric acid) and to a lower rate--lead and arsenic. The tendencies of air pollution are favourable, save lead pollution, the concentration of which increases during the last years. The structure of the morbidity of the population point out that there is an increase of the relative part of diseases, which could be related to the systematic effect of heavy metals and arsenic (malignant neoplasms, diseases of the nervous and cardiovascular system, diseases of the kidney). More frequently are observed acute and chronic cases of diseases of the respiratory tract.

Air Pollution↗
PubMed2003

[A case-crossover study of ambient air pollution and daily mortality in Shanghai].

OBJECTIVE: Using case-crossover design to estimate the acute effect of ambient air pollution on daily mortality in Shanghai, and to explore the applicability of if in studying the acute health effects of air pollution. METHODS: Case-crossover technique was used to evaluate the relationship between air pollution and daily mortality from June 2000 to December 2001 in Shanghai. The results of the bi-directional control sampling approach were compared with unidirectional approach. RESULTS: The validity of relative risks in case-crossover studies varied greatly depending on the strategy used in control sampling. When a bi-directional six control sampling approach was used an increase of relative risk of non-accident mortality on each 10 micro g/m(3) over a 48-hr moving average of PM(10), SO(2) and NO(2) corresponds to 1.003 (95% CI: 1.001 - 1.005), 1.016 (95% CI: 1.011 - 1.021), and 1.020 (95% CI: 1.012 - 1.027) respectively was seen. CONCLUSION: The results reinforced the deleterious role of current air pollution level on human health in Shanghai, and provided information on the applicability of case-crossover design in studying the acute health effects of air pollution.

Air Pollution↗
PubMedDate not supplied

[Efficiency of alfalfa and reed in the phytoremediation of hydrocarbon polluted soil].

The efficacy of plants as means of decontaminating hydrocarbon-polluted soil has been studied. Ditch reed (Phragmites australis) and alfalfa (Medicago sativa) markedly intensified processes of pollutant destruction, the effect being particularly pronounced in the case of polycyclic aromatic hydrocarbons (PAHs). Comparative analysis of microflora in soils (including those devoid of plants and rhizosphere) demonstrated that, in addition to preventing the pollutant-induced decrease in the amount of heterotrophic microorganisms, the plants stimulated their development, significantly increasing the population of destructors. Effects of plants on major physiological groups of soil microorganisms under conditions of pollution were ambiguous. The rhizosphere consortium of alfalfa was less susceptible to effects of pollutants than that of reed.

Biodegradation, Environmental↗
PubMed2003

[Effects of simulated acid rains on Cd, Cu and Zn release and their form transformation in polluted soils].

The release and form transformation of Cd, Cu, and Zn in polluted red soil and yellow red soil affected by simulated acid rains were studied through batch equilibrium experiments. The results showed that the release of test heavy metals increased significantly with decreasing pH value of simulated acid rain. Their release amount was negatively correlated to the pH value of acid rains. In polluted red soil and yellow red soil, Cd existed mainly in exchangeable form, and Cu in organically bound and Mn oxide-occluded forms. Zn existed mainly in residual and exchangeable forms in polluted red soil, and in residual and organically bound forms in polluted yellow red soil. To some extents, the release of Cd, Cu and Zn and the chemical forms of Cd and Zn in test soils were affected by soil organic matter content and CEC. The release amount of bio-available Cd and Cu in polluted red soil and yellow red soil was increased greatly with the increasing acidity of simulated acid rains, but the transformation of Zn from stable to bio-available form was not obvious.

Acid Rain↗
PubMed2004

[Air pollution and cardiovascular disease in Trondheim].

BACKGROUND: There is some evidence linking air pollution to cardiovascular morbidity. Our aim was to examine whether there is a correlation between air pollution and cardiovascular morbidity in the city of Trondheim, Norway. MATERIAL AND METHODS: We compared the mean daily number of admissions for cardiovascular disease to the St. Olav University hospital on days with relatively low and high levels of PM10 (1993-2001), PM2,5, NO, NO2, SO2, O3, toluene and paraxylene (1998-2001). A time series analysis was carried out to see how day-to-day variations in concentrations of air pollutants correlated with the number of hospitalizations for cardiovascular disease. RESULTS: In the bivariate analysis, the mean daily number of hospitalizations was found to be significantly higher (p < 0.05) on days with NO and NO2 levels above the 80 th percentile (57.6 microg/m3 and 43.1 microg/m3, respectively) than on days with pollutant levels below the 20th percentile (11.3 microg/m3 and 16.9 microg/m3, respectively). Time series analysis did not show any statistically significant correlation between day-to-day variations in air pollution and hospital admissions for cardiovascular disease. INTERPRETATION: The findings regarding NO2 and NO indicate that exposure to gases and/or ultra-small particles from diesel exhaust may influence cardiovascular morbidity.

Acute Disease↗
PubMed2004

Effects of traffic pollution on the genetic structure of Poa annua L. populations.

The genetic composition of Poa annua L. populations with a series of traffic pollution was studied by starch electrophoresis. Five enzyme systems were stained. The results showed that: (1) Traffic pollution can dramatically change genotypic frequencies at some loci of P. annua populations. Significant deviations from Hardy-Weinberg equilibrium were observed on loci Fe-1 and Me due to the excess of heterozygotes in some populations. (2) The effective number of alleles per locus and the observed and expected heterozygosity were higher in the pollution series than in the clear control site (Botanic Park population), but the increase was not related with the pollution extent. (3) Most genetic variation was found within populations, and only 6.21% was among populations of the polluted series. Slightly higher differentiation (FST = 7.98%) was observed when the control population was included. (4) The calculated gene flow (Nm) is 2.8841 per generation. The mean of genetic identity is 0.9864 and the genetic distance average to 0.0138.

Air Pollutants↗
PubMed2004

Incorporating sorption/desorption of organic pollutants into river water quality model.

Preliminary research was conducted about how to incorporate sorption/desorption of organic pollutants with suspended solids and sediments into single-chemical and one-dimensional water quality model of Jinghang Canal. Sedimentation-resuspension coefficient k3 was deduced; characteristics of organic pollutants, concentrations and components of suspended solids/sediments and hydrological and hydraulic conditions were integrated into k3 and further into river water quality model; impact of sorption/desorption of organic pollutants with suspended solids and sediments on prediction function of the model was discussed. Results demonstrated that this impact is pronounced for organic pollutants with relatively large Koc and Kow, especially when they are also conservative and f.o of river suspended solids/sediments is high, and that incorporation of sorption/desorption of organic pollutants into river water quality model can improve its prediction accuracy.

Adsorption↗
PubMed2004

Assessment of microbial natural attenuation in groundwater polluted with gasworks residues.

Intrinsic biodegradation, representing the key process in Natural Attenuation, was examined at a tar-oil polluted disposal site. Methods to assess microbial natural attenuation of BTEX and PAH included analysis of groundwater hydrochemistry, pollutant profiles, composition of the microflora, and microcosm studies. In the polluted groundwater downgradient the disposal site, oxygen and nitrate were only available adjacent to the groundwater table and at the plume fringes. In the anaerobic core of the plume, a sequence of predominating redox zones (methanogenic, sulphate-reducing, Fe(III)-reducing) was observed. Changing pollutant profiles in the plume indicated active biodegradation processes, e.g. biodegradation of toluene and naphthalene in the anaerobic zones. High numbers of microorganisms capable of growing under anaerobic conditions and of aerobic pollutant degrading organisms confirmed the impact of biodegradation at this site. In microcosm studies, the autochthonous microflora utilised toluene, ethylbenzene, and naphthalene under sulfate- and Fe(III)-reducing conditions. Additionally, benzene and phenanthrene were degraded in the presence of Fe(III). Under aerobic conditions, all BTEX and PAH were rapidly degraded. The microcosm studies in particular were suitable to examine the role of specific electron acceptors, and represented an important component of the multiple line of evidence concept to assess natural attenuation.

Aerobiosis↗
PubMed2004

The association of daily diabetes mortality and outdoor air pollution in Shanghai, China.

The objective of the study reported here was to assess the association between air pollution and daily diabetes mortality in Shanghai. Death records were collected for all individuals who lived in the Zhabei district of Shanghai and died from diabetes from January 1, 2001, to December 31, 2002. The authors used a time-series approach to study the acute effects of air pollution on diabetes mortality after controlling for long-term trends, weather variables, and day of the week. Each increase of 10 microg/m3 in PM10, SO2, or NO2 was found to correspond, respectively, to a 1.006 (95 percent CI: 1.000-1.012), 1.011 (95 percent CI: 0.990-1.032), or 1.013 (95 percent CI: 1.000-1.026) relative risk of diabetes mortality in Shanghai. The air pollutants also were observed to have a greater effect on diabetics than on nondiabetics. These findings provide new evidence for the association between air pollution and diabetes mortality risk, and suggest that diabetics are more susceptible to air pollution than are nondiabetics.

Air Pollutants↗