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1.
The relationship between indoor and outdoor particulate air pollution was investigated at an urban background site on the Payambar Azam Campus of Mazandaran University of Medical Sciences in Sari, Northern Iran. The concentration of particulate matter sized with a diameter less than 1 μm (PM1.0), 2.5 μm (PM2.5), and 10 μm (PM10) was evaluated at 5 outdoor and 12 indoor locations. Indoor sites included classrooms, corridors, and office sites in four university buildings. Outdoor PM concentrations were characterized at five locations around the university campus. Indoor and outdoor PM measurements (1-min resolution) were conducted in parallel during weekday mornings and afternoons. No difference found between indoor PM10 (50.1 ± 32.1 μg/m3) and outdoor PM10 concentrations (46.5 ± 26.0 μg/m3), indoor PM2.5 (22.6 ± 17.4 μg/m3) and outdoor PM2.5 concentration (22.2 ± 15.4 μg/m3), or indoor PM1.0 (14.5 ± 13.4 μg/m3) and outdoor mean PM1.0 concentrations (14.2 ± 12.3 μg/m3). Despite these similar concentrations, no correlations were found between outdoor and indoor PM levels. The present findings are not only of importance for the potential health effects of particulate air pollution on people who spend their daytime over a period of several hours in closed and confined spaces located at a university campus but also can inform regulatory about the improvement of indoor air quality, especially in developing countries.  相似文献   

2.
This study was conducted in the urban environment of Varanasi, India, to evaluate the plant responses to urban air pollution. Twenty sites were selected in four different zones of the city. At each site, seven woody perennials of same age classes were selected. Out of the four zones (I, II, III and IV), zone IV was used as a reference (control) zone as it received the minimum pollution input. Plant species growing in polluted and control areas were compared with respect to foliar dust load, per cent leaf area injury, leaf area, specific leaf weight and chlorophyll, ascorbic acid, SO 4 2– S and total N concentration in the leaves. Results indicated that the air pollution level in Varanasi causes leaf damage, reduces leaf area, specific leaf weight and chlorophyll, ascorbic acid and total N concentrations in the leaves. Sulphur concentration in leaves increased with increasing level of SO2 in the ambient air. The magnitude of such changes was maximum at the zone receiving maximum pollution load. Carissa carandas was found to be the most sensitive species and Bougainvillea spectabilis, the least. The study shows that the urban air pollution level in Varanasi is detrimental for the growth of plants involved in this study.  相似文献   

3.
A field study was carried out at six locations in the Lazio region (Central Italy) aimed at characterising atmospheric particulate matter (PM10 and PM2.5) from the point of view of the chemical composition and grain size distribution of the particles, the mixing properties of the atmosphere, the frequency and relevance of natural events. The combination of four different analytical techniques (ion chromatography, X-ray fluorescence and ICP for inorganic components, thermo-optical analysis for carbon compounds) yielded sound results in terms of characterisation of the air masses. During the first three months of the study (October-December 2004), many pollution events of natural (sea-salt or desert dust episodes) or anthropogenic nature were identified and characterised. More than 90% of the collected mass was identified by chemical analysis. The central role played by the mixing properties of the lower atmosphere when pollution events occurred was highlighted. The results show a major impact of primary anthropogenic pollutants on traffic stations and a homogeneous distribution of secondary pollutants over the regional area. An evaluation of the sources of PM and an identification of possible reliable tracers were obtained using a chemical fractionation procedure.  相似文献   

4.
A field study was carried out at six locations in the Lazio region (Central Italy) aimed at characterising atmospheric particulate matter (PM10 and PM2.5) from the point of view of the chemical composition and grain size distribution of the particles, the mixing properties of the atmosphere, the frequency and relevance of natural events. The combination of four different analytical techniques (ion chromatography, X-ray fluorescence and ICP for inorganic components, thermo-optical analysis for carbon compounds) yielded sound results in terms of characterisation of the air masses. During the first three months of the study (October–December 2004), many pollution events of natural (sea-salt or desert dust episodes) or anthropogenic nature were identified and characterised. More than 90% of the collected mass was identified by chemical analysis. The central role played by the mixing properties of the lower atmosphere when pollution events occurred was highlighted. The results show a major impact of primary anthropogenic pollutants on traffic stations and a homogeneous distribution of secondary pollutants over the regional area. An evaluation of the sources of PM and an identification of possible reliable tracers were obtained using a chemical fractionation procedure.  相似文献   

5.
This paper reports the adaptational response of a tropical shrub Carissa Carandas L. to urban air pollution stress in Varanasi, India. Saplings of C. carandas were grown at a density of one per pot and kept for two years at 25 selected sites in the urban environment. Different sites received different levels of air pollution input. Changes in vegetative growth pattern (leafing and branching), in morphological features and in the distribution of biomass to above and below ground structures were considered in relation to the ambient air quality.Different levels of air pollution input produced different sets of harmful effects. Although the air pollution level at Varanasi reduced the plant height, basal diameter, canopy area, leaf area and total plant biomass of C. carandas, this species retained a major fraction of its photosynthate to above-ground plant parts where foliage assumes predominance. Since carbon gain is dependent not only on the rate of carbon acquisition per unit leaf tissue but also on the amount of photosynthetic tissue present, a shift in relative contribution of photosynthate to leaf production and shoot growth appears to be a pollution-induced adaptive response in C. carandas.  相似文献   

6.
Air pollution is threat to the lives of people living in big cities of Pakistan. In Lahore 1,250 people die annually because of air pollution.Mass transit system that can be put forth as solution to urban air pollution is contingent with right choice of system and its affiliation with motorized vehicles and nature of urban air pollution.Existing mass transit system in Lahore due to untrue operation causes surfeit discharge of motor vehicular carbon monoxide. Tended relationships of mass transit system with motorized vehicles and urban air pollution are quite noteworthy. The growing motor vehicles (a consequence of flawed public mass transit system) are potential source of urban air pollution. This paper attempts to highlight correlations and regression curves of existing mass transit system. Further it recommends a two facet approach for reduction of motor vehicular air pollution in Lahore.  相似文献   

7.
A health hazard, specifically the leukaemia risk, is evaluatedfrom different sources of benzene exposure with relation to apopulation living in an urban area of Italy. The population exposure is calculated for a reference year by sexand lyfestyle, with respect to smokers and non smokers. Potentialhealth risk is therefore quantified by means of mathematicalmodels and the relative significance of the different sources is described. The results of the analysis are useful for the identification ofappropriate risk reduction strategies to minimize exposure, inparticular when resulting from lifestyle and personal activities.  相似文献   

8.
重庆大气污染与儿童肺功能横截面研究   总被引:1,自引:0,他引:1  
1995年 ,在重庆市城区及远郊区进行了儿童家庭问卷调查、气溶胶 (PM1 0 、PM2 .5 )及 SO2 的测试 ,并在两个点 (城区华新小学 ,远郊北碚红岩小学 )进行二次儿童肺功能的测定。通过城区和郊区 3 53 6例 (其中男性 1 74 4例 ,女性 1 792例 )儿童肺功能数据的比较 ,说明重庆大气污染 ,特别是气溶胶的污染已影响到儿童肺功能。与美国比较 ,重庆儿童较美国的儿童肺功能 (FVC,FEV1 )要低 9%~ 1 4 %。同时得到青春前期 (7~ 1 4岁 )儿童肺功能 (FVC,FEV1 )的参考值的计算公式  相似文献   

9.
10.
The geography and climate of the Santiago basin are, in general, unfavorable for the diffusion of air pollutants. Consequently, extreme events occur frequently during the high pollution season extending from April to August. The meteorological conditions concurrent with those extreme events are mainly associated with the leading edges of coastal lows that bring down the base of the semipermanent temperature inversion reducing the dirunal growth of the surface mixed layer. In order to produce an objective 12 to 24-hour episode forecast, a two-way multivariate discriminant analysis has been used in the definition of a meteorological air-pollution potential index (MAPPI), separating high and low meteorological air-pollution potential days. The same procedure has been applied in the selection of the most efficient predictors for the MAPPI objective forecast, based on 12 and 24 UTC radiosonde data at Quintero, about 100 km to the NW of Santiago. Results indicate about 70% correctly forecasted days, with satisfactory skill-scores relative to persistency. The strong persistency characterizing the most efficient predictors in the 12-hour objective forecast scheme, makes the prediction of the first and last days of any particular air-pollution potential episode particularly difficult. To overcome this problem, a new set of predictors based on continuous measurements near the level of the top of the temperature inversion layer (900 hPa during air-pollution episodes) is being tested. Preliminary results indicate that the time-integrated zonal wind component at that level is a reliable precursor for both the onset and the end of air-pollution potential episodes.  相似文献   

11.
12.
兰州市空气污染对儿童肺功能影响的前瞻性研究   总被引:1,自引:0,他引:1  
从不同的角度阐述了室内外空气污染对儿童肺功能 ,特别是小气道功能的影响及其影响程度的前瞻性研究结果。并通过多因素、多指标的综合分析 ,揭示了一些影响儿童肺功能的主要因素。指出了从保护人体健康的角度来说 ,好的环境空气质量和良好的室内空气质量同样重要  相似文献   

13.
A biennial integrated survey, based on the use of vascular plants for the bioindication of the effects of tropospheric ozone, was performed in the area of Pisa (Tuscany, Central Italy). It also investigated the distribution of selected trace elements in plants and the data were compared with those obtained from the use of passive samplers, automatic analysers of ozone and lichen biodiversity. Photochemically produced ozone proved to be present during the warm season, with maximum hourly means surpassing 100 ppb: the use of supersensitive tobacco Bel-W3 confirmed the value of detailed, cost-effective, monitoring surveys. Trials with clover clones demonstrate that sensitive plants undergo severe biomass reduction in the current ozone regime. The mean NC-S (clover clone sensitive to ozone):NC-R (resistant) biomass ratio ranged from 0.7 (in 1999) to 0.5 (in 2000). The economic impact of these reductions deserves attention. The data obtained using passive ozone samplers exceeded those obtained using an automatic analyser. The mapping of epiphytic lichen biodiversity was not related to the geographical ozone distribution as can be seen from the tobacco's response. Lettuce plants grown under standardized conditions were used positively as bioaccumulators of trace elements: Pb was abundantly recovered, but a large portion of this element was removed by washing.  相似文献   

14.
Tehran is one of the megacities of the world with a population of over eight million. Its air is highly polluted mainly due to the suspended particulate matters, which encompasses a wide spectrum of chemical elements. These elements based on their type, size, and impact on the life cycle have various environmental and heath risks. In this research, the neutron activation method is used to determine the concentration levels of Al, Ba, Fe, Mg, and V in the urban air. Thus, two districts of Tehran with different characteristics are selected. District 21 includes much of the industries located in Tehran metropolitan and is considered as an industrial area. In contrast, district 22 lacks any significant industrial activity. It is a newly established and expanding district adjacent to district 21 with a great deal of constructional activities. For the measurement of the suspended particulate matters in the air, the various sections of the aforesaid districts with industrial, residential, heavily congested traffic, residential/commercial, residential/heavily congested traffic, and residential/industrial classifications were identified. Subsequently, 24 sampling stations were selected. The sampling of the suspended particulate matters was conducted with the aid of a high volume pump containing 125 mm cellulose filters in two different time intervals. After completion of the sampling process, the samples were prepared and sent to the research reactor of the Iran Nuclear Energy Organization for Neutron Activation. During the next steps, the radiations emitted from the samples were registered, the radiation curves were plotted, and the amounts of the trace elements were determined. As a result, the average concentration levels of Al, Ba, Fe, Mg, and V were identified to be 3.301140, 2.273658 × 10, 4.0681696 × 10???1, 3.5525475 × 10???1, and 3.04075 × 10???2 μg/m3, respectively. Moreover, the emission sources of the aforesaid elements into the air were identified. The concentration levels of these elements in the industrial and heavily congested traffic sections were higher. Finally, it was concluded that the statistical analysis of these elements presents a meaningful correlation among them.  相似文献   

15.
Organochlorine pesticide (OCP) cycling was studied in the area of Banja Luka, Bosnia and Herzegovina, over 3 days in summer with high temporal (4 h-means) and spatial (3 sites distanced 3-6 km) resolutions. Elevated levels of DDX compounds (i.e. o,p'- and p,p'-isomers of DDT, DDE and DDD, 44-74 pg m(-3) at the urban sites and 27 pg m(-3) as a background level), HCH (α-, β- and γ-isomers, 52-70 vs. 147 pg m(-3)), HCB (34-48 vs. <0.1 pg m(-3)) and pentachlorobenzene (6.8-9.9 vs. 6.0 pg m(-3)) were found. The variation of OCP levels at the two urban sites was not in phase, except for most DDX compounds. This was related to background levels, which for HCH were higher than in the urban area. Vertical profiles between samples collected from 1.1 and 2.3 m (part of the time 0.6 and 2.3 m) above a soil, which was only moderately contaminated by OCPs (0.12 ng g(-1) HCH, 0.11 ng g(-1) DDX, 0.44 ng g(-1) HCB) were analysed. Volatilisation from the ground caused negative vertical concentration gradients of HCH isomers (day and night), but not for HCB (except for 1 day-time sample) and DDX compounds (except p,p'-DDD, day-time, sporadically). The concentration in air and the vertical concentration gradient of the HCH isomers varied with air temperature (day-time maxima), while the variation of the HCB concentration was inversely related to air temperature and was determined by mixing (night-time maxima). α- and β-HCH were volatilised from soil throughout the three days, even during periods of cooling. Fugacity calculations, based on the absorption in soil organic matter as the process determining retention in soil, underestimated the volatilisation of β-HCH and p,p'-DDD. It is concluded that the representativeness of point measurements of OCPs in urban areas is limited by the spatial variability of soil contamination.  相似文献   

16.
A comparative study was undertaken at two different sites (one urban, one suburban) in Greater London in order to examine whether there was a relationship between publicly available air quality data and the public's perception of air quality. Perceptions of air quality and its role as a potential quality of life indicator was also investigated. A total of 200 people were interviewed in Wood Green and Wimbledon in 1999 and air quality data were obtained simultaneously from the nearest appropriate monitoring station. The study has enabled a comparison between the public's perception of air quality and the actual monitored concentration values. The survey results reveal how seriously the public regards air pollution from road traffic in terms of their quality of life and identifies the attitudes of the public to nuisance from road traffic. The results reveal that the public's perception of air quality is not a reliable indicator of the actual levels of air pollution in their area. The results also revealed that air pollution issues generated as a result of road traffic are of high importance in terms of people's quality of life when compared to other aspects of their quality of life. The study revealed that residents in the urban area (Wood Green) were more disturbed by road traffic than residents in the suburban area (Wimbledon). Out of all the disturbances listed, it was found that residents were more disturbed by vehicle-derived fumes, dust and dirt than other aspects of road traffic related nuisance. The TELETEXT/CEEFAX service on air quality was little used by the public as a means of obtaining information on air pollution.  相似文献   

17.
To supplement an epidemiological investigation into respiratory cancer, a synthetic fabric called tak was used to study the deposition of atmospheric metal pollution within the town of Armadale, central Scotland. Pollution maps showed high concentrations of several metals in areas close to the town's steel foundry and in a second area in the north of the town. Through further statistical analyses, those metals were identified which had probably been emitted by the foundry, and temporal variations in metal deposition patterns were examined. The advantages of this method of low technology sampling, which include the low cost and a high density of sampling sites, are described.  相似文献   

18.
The analysis of pollution data was the support for the proposed remodelation of the network and allowed an estimation of the Air Quality evolution since 1968.The most important pollution sources in Oporto area are the motor traffic, one oil refinery and one petrochemical complex.Strong acidity levels are generally small, but black smoke concentrations are similar to that observed in several European cities.The interpretation of the temporal evolution of network yearly averages, is sometimes not reliable, in consequence of not being possible to get the mean validation of every sites for all years.The network should be increased installing stations in the oldest commercial areas where sulfur dioxide, black smoke, nitrogen oxides, hidrocarbons, carbon monoxide, lead and ozone should be measured. Sulfur dioxide and black smoke should be measured too, in six more areas of the metropolitan Oporto.  相似文献   

19.
An intensive two month measurement campaign has been performed during a two year study of major component composition of urban PM10 and PM2.5 in Ireland (J. Yin, A. G. Allen, R. M. Harrison, S. G. Jennings, E. Wright, M. Fitzpatrick, T. Healy, E. Barry, D. Ceburnis and D. McCusker, Atmos. Res., 2005, 78(3-4), 149-165). Measurements included size-segregated mass, soluble ions, elemental carbon (EC) distributions, fine and coarse fraction organic carbon (OC) and major gases along with standard meteorological measurements. The study revealed that urban emissions in Ireland had mainly a local character and therefore were confined within a limited area of 20-30 km radius, without significantly affecting regional air quality. Gaseous measurements have shown that urban emissions in Ireland had clear, but fairly limited influence on the regional air quality due to favorable mixing conditions at higher wind speeds, in particular from the western sector. Size-segregated mass and chemical measurements revealed a clear demarcation size between accumulation and coarse modes at about 0.8 microm which was constant at all sites. Carbonaceous compounds at the urban site accounted for up to 90% of the particle mass in a size range of 0.066-0.61 microm. Nss SO4(2-) concentrations in PM2.5 were only slightly higher at the urban site compared to the rural or coastal sites, while NO3- and NH4+ concentrations were similar at the urban and coastal sites, but were a factor of 2 to 3 higher than at the rural site. OC was highly variable between the sites and revealed clear seasonal differences. Natural or biogenic OC component accounted for <10% in winter and up to 30% in summer of the PM2.5 OC at urban sites. A contribution of biogenic OC component to PM2.5 OC mass at rural site was dominant.  相似文献   

20.
The basic premise underlying the approach presented in the paper is the assumption that humans are unique beings that can evaluate. The environment is described as a system of resources satisfying human needs. The assessment of the effects of environmental pollution derives from the fact that there is, or will be, non-satisfaction of needs resulting from a reduction in environmental resources.  相似文献   

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