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1.
In the study reported here semipermeable membrane devices (SPMDs) were used to sample 28 PAHs and 19 PCBs in the gas phase in 15 single-family houses located in an area where domestic wood burning is widespread. Eight of the households used wood burning appliances whereas the others used other systems for residential heating. Most of the studied compounds were found in the houses: the PAHs at levels that were similar to or slightly higher than published SPMD-sampled levels for background or urban sites in Sweden, and the PCBs at levels that were somewhat lower than those recently found in both indoor and outdoor urban locations. A principal component analysis revealed that wood-burning heating systems may contribute to PAHs in indoor air. The sources may be emissions indoors or penetration from outdoors. The convenience of SPMD technology facilitates its use for semi-quantitative screening and monitoring of various persistent organic compounds indoors in dwellings and working environments.  相似文献   

2.
宣威市和富源县位于我国云南省东北部,是全世界肺癌发病率最高的地区之一。当地居民在不通风的房间内燃烧烟煤做饭或取暖造成了严重的室内空气污染。研究表明,长期暴露在燃煤造成的污染物中是导致两地居民肺癌持续高发的主要原因,多环芳烃是最可疑的致病因子之一。2008年1月,分别用聚胺脂泡沫和玻璃纤维滤膜采集了当地9个点位室内、室外空气中气相和颗粒物相中的多环芳烃,同时采集了对应点位的土壤样品。通过对样品的分析,考察了当地空气和土壤中多环芳烃的污染水平、特征以及来源。结果证明,当地空气和土壤中存在严重的多环芳烃污染,室内污染显著高于室外,然而随着当地工业的发展室外污染同样不可忽视,主成分分析结合比值法证明,当地室内外多环芳烃的主要污染源来自于煤炭的燃烧。对空气颗粒物和土壤中多环芳烃浓度进行了比较,对土壤中多环芳烃的来源进行了验证。  相似文献   

3.
The aim of this research is to evaluate the ability of transplanted lichen Pseudovernia (P). furfuracea to biomonitor and bioaccumulate in urban indoor environments. The elements As, Cd, Cr, Cu, Hg, Ni and Pb and 12 selected polycyclic aromatic hydrocarbons (PAHs) were used to assess P. furfuracea as a biomonitoring tool for the indoor air quality of school environments. To achieve this purpose, lichen samples were exposed for 2 months in the outdoor and indoor environments of five school settings located in urban and rural areas. The results demonstrated that transplanted lichen P. furfuracea is a suitable biomonitoring tool for metals and PAHs in indoor settings and can discriminate between different levels of air pollution related to urbanisation and indoor conditions, such as those characterised by school environments. A transplanted lichen biomonitoring strategy is cost-effective, “green”, educational for attending children and less “invasive” than traditional air sampling methods. The feasibility of indoor monitoring by P. furfuracea is a relevant finding and could be a key tool to improve air quality monitoring programmes in school scenarios and thus focus on health prevention interventions for children, who are one of the most susceptible groups in the population.  相似文献   

4.
于非采暖季和采暖季分别采集某石化化工行业聚集城市中心城区室内外PM_(2.5)样品,采用高效液相色谱法分析PM_(2.5)上载带的16种PAHs,对其分布特征、来源以及室外PAHs污染对室内污染的贡献进行了初步探讨。结果表明,研究区域非采暖季和采暖季室外PM_(2.5)中ΣPAHs浓度日均值分别为36.3、294 ng/m~3,室内PM_(2.5)中ΣPAHs浓度分别为14.8、84.6 ng/m~3,均以4、5环PAHs为主;室内PAHs主要来自室外渗透污染,但同时明显存在室内排放源贡献;PAHs来源分析进一步证实研究区域PAHs主要来自煤炭、石油等不完全燃烧,采暖季煤炭燃烧源贡献更突出。  相似文献   

5.
PUF大气被动采样技术对POPs的采样计算   总被引:2,自引:0,他引:2  
随着《斯德哥尔摩公约》的实施,大气中持久性有机污染物(POPs)的大气被动采样(PAS)观测技术得到了快速发展,相比于传统大气主动采样技术,PAS技术具有明显的优势。以应用最为广泛的聚氨酯软性泡沫材料大气被动采样(PUF-PAS)为例,重点阐述和讨论了3种通过大气被动采样技术来计算污染物在空气中的浓度的方法,并对其采样原理和发展趋势进行了简要介绍。  相似文献   

6.
Determinations of PCB were carried out as part of a project aimed at developing cleanup methods for PCB-containing elastic sealant used in outdoor joints between concrete blocks. The goals of the project were to develop methods, which minimise the spread of PCB to the outdoor environment and to indoor air, and which keep the PCB levels as low as reasonably possible in the workplace environment whilst removing the elastic sealant. The following PCB determinations were carried out: (1) concentration in the elastic sealant; (2) concentration in the concrete close to the sealant; (3) concentration in soil; (4) concentration in the indoor air; and (5) concentration in the air in the workplace environment. The cleanup process consisted of a number of different steps: (1) cutting the elastic sealant with an oscillating knife; (2) grinding the concrete with a mechanical machine; (3) sawing the concrete with a mechanical saw and (4) cutting the concrete with a mechanical chisel. In all these different steps a high capacity vacuum cleaner connected to the machines was used. The elastic sealant contained 4.7 to 8.1% total PCB of a technical product with a composition most similar to Clophene A40. The concrete close to the sealant (first 2 mm) contained 0.12 and 1.7% total PCB at two different places. The pattern of the PCB in the concrete resembled that of the sealant. PCB concentrations in the soil from the ground close to the building were 0.1 and 0.3 ppm at two different places before the remedial action. The source of the PCB in the soil is most likely the sealant as the PCB pattern is similar for the two materials. The PCB levels in the workplace air at the beginning of the project, when the techniques were not fully developed, were generally above the occupational exposure limit of 10 micrograms m-3 (up to 120 micrograms m-3). Later when the techniques were optimised to better take care of dust and gases produced during the cutting and grinding etc., the levels were below or close to 10 micrograms m-3. The pattern of the PCB in the workplace air was different from that of the sealant and contained higher levels of lighter components. The PCB concentrations in the indoor air were measured before and during the remedial process. The levels were around 600 ng m-3 and there was no significant increase during the removal of the sealant. The PCB level after the remedial action will be measured later. The pattern of the PCB in the indoor air was different from that of the sealant as well as from that of the workplace air. Higher levels of the lighter PCB were present indoors compared to the composition in both workplace air and in sealant. Extracts of PCB were analysed by GC-MS with a SIM method (selected ion monitoring). Standard procedures were used for extraction of solid materials. For the air samples an OVS tube was used with XAD-2 as adsorbent. The filter and adsorbent were extracted with toluene. This work shows that it is important to perform remedial action of PCB-containing elastic sealant as: (1) there is a spread of PCB to the indoor air giving high enough concentrations to make this the main PCB load on humans living in the apartments studied in this project; (2) large amounts are spread to the soil from these sealants; and (3) many of the PCB-containing elastic sealants used need to be changed from a functional perspective.  相似文献   

7.
A comparison between the sampling and analytical methods used by Canadian (IADN) and German (OSPAR) regional monitoring networks for persistent organic pollutants was conducted from September 2002 to October 2003 at a rural site in Ontario, Canada. Polycyclic aromatic hydrocarbons (PAHs) and the currently-used pesticide lindane were measured in precipitation and ambient air samples. Overall the two networks sampling and analytical methods agreed well in their results of deposition (wet and dry particulate). Lindane concentrations between the two networks agreed well in the air samples while too few precipitation samples could be compared to conclude on agreement. The lindane seasonal profile with a peak in spring-early summer was consistent with previous results pointing to the continued use of this pesticide in 2002-2003 in Canada. Annual lindane wet depositions were comparable between the two network methodologies. PAHs concentrations in precipitation and in gas phase agreed well while there was a discrepancy for particulate PAHs in air. This study confirmed that the use of data from the two regional POPs monitoring networks for hemispherical modelling studies is warranted.  相似文献   

8.
Spatial mapping of city-wide PBDE levels using an exponential decay model   总被引:1,自引:0,他引:1  
Passive air samplers (PAS) consisting of polyurethane foam (PUF) disks were deployed at 6 outdoor air monitoring stations in different land use categories (commercial, industrial, residential and semi-rural) to assess the spatial distribution of polybrominated diphenyl ethers (PBDEs) in the Brisbane airshed. Air monitoring sites covered an area of ~1143 km(2) and PAS were allowed to accumulate PBDEs in the city's airshed over three consecutive seasons commencing in the winter of 2008. The average sum of five (∑(5)) PBDEs (BDEs 28, 47, 99, 100 and 209) levels were highest at the commercial and industrial sites (12.7 ± 5.2 ng PUF(-1)), which were relatively close to the city center and were a factor of 8 times higher than residential and semi-rural sites located in outer Brisbane. To estimate the magnitude of the urban 'plume' an empirical exponential decay model was used to fit PAS data vs. distance from the CBD, with the best correlation observed when the particulate bound BDE-209 was not included (∑(5)-209) (r(2) = 0.99), rather than ∑(5) (r(2) = 0.84). At 95% confidence intervals the model predicts that regardless of site characterization, ∑(5)-209 concentrations in a PAS sample taken between 4-10 km from the city centre would be half that from a sample taken from the city centre and reach a baseline or plateau (0.6 to 1.3 ng PUF(-1)), approximately 30 km from the CBD. The observed exponential decay in ∑(5)-209 levels over distance corresponded with Brisbane's decreasing population density (persons/km(2)) from the city center. The residual error associated with the model increased significantly when including BDE-209 levels, primarily due to the highest level (11.4 ± 1.8 ng PUF(-1)) being consistently detected at the industrial site, indicating a potential primary source at this site. Active air samples collected alongside the PAS at the industrial air monitoring site (B) indicated BDE-209 dominated congener composition and was entirely associated with the particulate phase. This study demonstrates that PAS are effective tools for monitoring citywide regional differences however, interpretation of spatial trends for POPs which are predominantly associated with the particulate phase such as BDE-209, may be restricted to identifying 'hotspots' rather than broad spatial trends.  相似文献   

9.
Odor and odorant emission rates from freshly dewatered biosolids in a dewatering building of a Water Reclamation Plant (WRP) are measured using the EPA flux chamber and wind tunnel methods. Experimental results are compared statistically to test whether the two methods result in similar emission rates when experiments are performed under field conditions. To the best of our knowledge the literature is void of studies comparing the two methods indoors. In this paper the two methods are compared indoors where the wind velocity and air exchange rate are pertinent field conditions and can be measured. The difference between emission rates of odor and hydrogen sulfide measured with the two methods is not statistically significant (P values: 0.505 for odor, 0.130 for H(2)S). It is concluded that both methods can be used to estimate source emissions but selection of the most effective or efficient method depends on prevailing environmental conditions. The wind tunnel is appropriate for outdoor environments where wind effects on source emissions are more pronounced than indoors. The EPA flux chamber depends on the air exchange rate of the chamber, which simulates corresponding conditions of the indoor environment under investigation and is recommended for estimation of indoor pollution sources.  相似文献   

10.
主动采样技术在中国大气POPs监测中的应用   总被引:2,自引:0,他引:2  
为了履行斯德哥尔摩公约,查明持久性有机污染物(POPs)在中国大气环境介质的存在水平,该研究首次采用主动采样技术,在中国境内大尺度范围内进行了环境大气中POPs的监测工作.利用主动采样技术,可以在短时间内采集数百立方米的大气样品.分别利用玻璃纤维滤膜采集大气颗粒物(固相)中的POPs,同时使用聚氨酯泡沫(PUF)吸附气态的POPs.该采样技术还便于样品的运输和保存.研究表明,大气主动采样技术可以很好地运用于区域大气POPs的监测工作并填补了我国在POPs履约监测中专用仪器设备的空白.  相似文献   

11.
Different approaches are used to verify the adequacy of emission factors (EFs) and their use in emission inventories of persistent organic pollutants (POPs). The applicability of EFs was tested using atmospheric dispersion modelling to predict atmospheric concentrations of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) and resulting toxic equivalents (SigmaTEQ) and particulate matter <10 microm (PM(10)) in two rural locations in northern England (UK). The modelling was based on general assumptions of fuel composition, consumption and heating needs to simulate emissions of POPs from the domestic burning of coal and wood where ambient measurements were made in the winter of 1998. The model was used to derive the local contribution to ambient air concentrations, which were estimated independently based on comparative air measurements. The results support the hypothesis that in both villages, the majority of PAHs and the lower chlorinated PCDFs were locally released. The situation for PCBs and polychlorinated naphthalenes (PCNs) was different. While the EFs show the release of both compound groups from the domestic burning of coal and wood, the ambient levels of these "legacy POPs" in the villages were still clearly dominated by other sources. Rural areas relying mainly on fossil fuels can exceed the proposed UK ambient air quality standard for benzo[a]pyrene during winter. The measured EFs were then used to estimate the importance of the domestic burning of coal and wood to national emission inventories for these compound classes. Extrapolations to the UK suggest that the domestic burning of pure wood and coal were minor emitters for chlorinated POPs but contributed strongly to PAH and PM(10) levels in 2000. Finally, the UK's national POPs emission inventories based on source inventories and EF, as used here, were compared to estimates derived using the increase in atmospheric concentration of selected POPs.  相似文献   

12.
Assessment of environmental and occupational exposure to chemicals can be performed with environmental monitoring (EM) and biological monitoring (BM). Biological monitoring was for a long time considered as a method complementary to environmental monitoring. At present this attitude is changing and in certain areas biological monitoring is applied as the method of choice for exposure and health-risk assessment. This paper examines advantages and disadvantages of those two approaches. In occupational settings environmental monitoring of exposure to VOCs seems to be superior to biological monitoring (possibility of simultaneous determination of components of mixtures, simple interpretation, possibility of evaluation of short-term exposure to local irritants). In the case of this group of compounds BM can be useful in selected cases such as evaluation of dermal absorption or efficiency of protective measures. In the case of metals both forms of monitoring can be used depending on the available methods for interpretation of results. BM of exposure may be considered as superior for evaluating the effects of exposure to lead, cadmium and mercury. However, quantitative evaluation of cancer risk after exposure to arsenic or chromium is possible only on the basis of determination in the air and the use of unit risk values. Both environmental and biological monitoring are useful for evaluation of occupational and environmental exposure to polycyclic aromatic hydrocarbons (PAHs). In certain areas such as evaluation of exposure to external tobacco smoking, cytostatic drugs, and pesticides, biological monitoring is the method of choice used for individual exposure assessment or tracing the trends of environmental exposure.  相似文献   

13.
The aim of this study is to examine the relative contribution of the outdoor concentration, the ventilation rate, the geometric characteristics of the indoor environment (i.e., extent of indoor surfaces and indoor volume), the deposition, and chemical reactions to the indoor air quality of the office microenvironment. For this case study, the NO, NO2, and O3 concentrations indoors and outdoors and TVOCs and CO2 concentrations indoors were measured in an office microenvironment in Athens, Greece, that was ventilated both naturally and mechanically. The calculated ventilation and loss rates and the measured outdoor concentrations of NO, NO2, and O3 were set as input to Multi-chamber Indoor Air Quality Model in order to study the temporal variation of the indoor NO, NO2, and O3 concentrations. Results showed that when the ventilation rate and outdoor concentration are high, the relative contribution of the transport process contributes significantly, while the chemical process depends on the contemporary interplay between the indoor O3, NO, and NO2 concentrations and lighting levels. The significance of each process was further examined by performing sensitivity tests, and it was found that the most important parameters were the deposition velocities, the UV infiltration rates (which determines the indoor chemical reaction rates), the ventilation rates, and the filtration (when a mechanical ventilation system is used). The effect of the hydrocarbon chemistry was not significant.  相似文献   

14.
This paper presents information about airborne mesophilic bacteria in the indoor and outdoor air of child day-care centers (CDCCs) in the city of Edirne, Turkey. Air samples were collected using the Petri plate gravitational settling method from the indoor and outdoor air of CDCCs. Counts of airborne bacteria were measured as colony forming units (CFU) collected by gravity onto Brain Heart Infusion Agar plates (with 5% sheep blood). Samples were taken monthly over a period of 12 months between January and December 2004. A total of 3,120 bacteria colonies were counted on 192 Petri plates. Four groups of culturable bacteria were identified: Gram-positive cocci, Gram-positive bacilli, endospore-forming Gram-positive bacilli, and Gram-negative bacteria. Airborne Gram-positive bacteria were the most abundant at more than 95% of the measured population. While Gram-positive cocci were more common in indoor environments, Gram-positive bacilli were more dominant in outdoor air. Bacteria commonly isolated from CDCCs were identified at a genus level. Staphylococcus (39.16%), Bacillus (18.46%), Corynebacterium (16.25%), and Micrococcus (7.21%) were dominant among the genera identified in the present study. The dominant genera identified in the day-care centers were Staphylococcus, Micrococcus, and Corynebacterium for indoor air and Bacillus, Corynebacterium, and Staphylococcus for outdoor air. Staphylococcus, Streptococcus, Bacillus, and Corynebacterium genera were found in samples from every month. Bacterial colony counts were compared by sampling location (indoors and outdoors), seasons, and meteorological factors. We found negative correlations between the monthly total outdoor bacterial counts and the sampling day’s average relative humidity and average rainfall, and the monthly average rainfall. Fluctuations in bacterial counts in different seasons were observed.  相似文献   

15.
This complex study presents indoor and outdoor levels of air-borne fine particles, particle-bound PAHs and VOCs at two urban locations in the city of Kaunas, Lithuania, and considers possible sources of pollution. Two sampling campaigns were performed in January-February and March-April 2009. The mean outdoor PM(2.5) concentration at Location 1 in winter was 34.5 ± 15.2 μg m(-3) while in spring it was 24.7 ± 12.2 μg m(-3); at Location 2 the corresponding values were 36.7 ± 21.7 and 22.4 ± 19.4 μg m(-3), respectively. In general there was little difference between the PM concentrations at Locations 1 and 2. PM(2.5) concentrations were lower during the spring sampling campaign. These PM concentrations were similar to those in many other European cities; however, the levels of most PAHs analysed were notably higher. The mean sum PAH concentrations at Locations 1 and 2 in the winter campaign were 75.1 ± 32.7 and 32.7 ± 11.8 ng m(-3), respectively. These differences are greater than expected from the difference in traffic intensity at the two sites, suggesting that there is another significant source of PAH emissions at Location 1 in addition to the traffic. The low observed indoor/outdoor (I/O) ratios indicate that PAH emissions at the locations studied arise primarily from outdoor sources. The buildings at both locations have old windows with wooden frames that are fairly permissive in terms of air circulation. VOC concentrations were mostly low and comparable to those reported from Sweden. The mean outdoor concentrations of VOC's were: 0.7 ± 0.2, 3.0 ± 0.8, 0.5 ± 0.2, 3.5 ± 0.3, and 0.2 ± 0.1 μg m(-3), for benzene, toluene, ethylbenzene, sum of m-, p-, o-xylenes, and naphthalene, respectively. Higher concentrations of VOCs were observed during the winter campaign, possibly due to slower dispersion, slower chemical transformations and/or the lengthy "cold start" period required by vehicles in the wintertime. A trajectory analysis showed that air masses coming from Eastern Europe carried significantly higher levels of PM(2.5) compared to masses from other regions, but the PAHs within the PM(2.5) are of local origin. It has been suggested that street dust, widely used for winter sanding activities in Eastern and Central European countries, may act not only as a source of PM, but also as source of particle-bound PAHs. Other potential sources include vehicle exhaust, domestic heating and long-range transport.  相似文献   

16.
Fugitive emissions from a slagging fixed-bed coal-gasification pilot plant were analyzed by flameless atomic absorption spectrophotometry, gas chromatography, and mass spectrometry for trace metal and trace organic species. Analysis of the size distributions of airborne particulate matter inside the plant showed an abundance of large metal-containing particles; outdoor distributions in the vicinity of the plant resembled the indoor distributions, suggesting the importance of the gasifier in influencing ambient air quality. This conclusion was further supported by identification of similar organic compounds inside and outside the plant. Trace element enrichment factors based on the earth's crustal composition were greater than those based on the composition of the lignite used in the gasifier, showing the importance of characterizing the proper source material when inverstigating chemical fraction during aerosol formation. Enrichments in the present study were much greater than those found in previous sampling during aborted start-up and cleaning procedures, where normal operating temperatures had not yet been reached. Both studies showed evidence of enrichment factors which decreased with increasing particle size. Although much of the airborne mass was associated with large particles having low respirability, the high concentrations of some metals indoors suggests that further assessment of potential occupational exposures is warranted.  相似文献   

17.
Measurement of air exchange rate provides critical information in energy and indoor-air quality studies. Continuous measurement of ventilation rates is a rather costly exercise and requires specific instrumentation. In this work, an alternative methodology is proposed and tested, where the air exchange rate is calculated by utilizing indoor and outdoor routine measurements of a common pollutant such as SO2, whereas the uncertainties induced in the calculations are analytically determined. The application of this methodology is demonstrated, for three residential microenvironments in Athens, Greece, and the results are also compared against ventilation rates calculated from differential pressure measurements. The calculated time resolved ventilation rates were applied to the mass balance equation to estimate the particle loss rate which was found to agree with literature values at an average of 0.50 h?1. The proposed method was further evaluated by applying a mass balance numerical model for the calculation of the indoor aerosol number concentrations, using the previously calculated ventilation rate, the outdoor measured number concentrations and the particle loss rates as input values. The model results for the indoors’ concentrations were found to be compared well with the experimentally measured values.  相似文献   

18.
The purpose of this study was to evaluate the level and composition of bacteria and fungi in the indoor air of an Italian office building equipped with a heating, ventilation and air conditioning (HVAC) system. Airborne bacteria and fungi were collected in three open-space offices during different seasons. The microbial levels in the outdoor air, supply air diffusers, fan coil air flow and air treatment unit humidification water tank were used to evaluate the influence of the HVAC system on indoor air quality (IAQ). A medium–low level of bacterial contamination (50–500 CFU/m3) was found in indoor air. Staphylococcus and Micrococcus were the most commonly found genera, probably due to human presence. A high fungal concentration was measured due to a flood that occurred during the winter. The indoor seasonal distribution of fungal genera was related to the fungal outdoor distribution. Significant seasonal and daily variation in airborne microorganisms was found, underlining a relationship with the frequency of HVAC system switching on/off. The results of this monitoring highlight the role of the HVAC system on IAQ and could be useful to better characterise bacterial and fungal population in the indoor air of office buildings.  相似文献   

19.
Fine particles (PM2.5) were sampled indoors and outdoors at 40 sampling sites; in ten classrooms in five schools, at ten preschools and 20 non-smoking homes, in three communities in Stockholm, Sweden, during nine 2-week periods. Each sampling site was sampled twice, once during winter and once during spring. The samples were analysed for elemental concentrations using X-ray fluorescence (XRF) spectroscopy. In all locations significantly higher outdoor concentrations were found for elements that are related to long-range transported air masses (S, Ni, Br and Pb), while only Ti was higher indoors in all locations. Similar differences for S, Br and Pb were found in both seasons for homes and schools. In preschools different seasonal patterns were seen for the long-range transported elements S, Br and Pb and the crustal elements Ti, Mn and Fe. The indoor/outdoor ratios for S and Pb suggest an outdoor PM2.5 particle net infiltration of about 0.6 in these buildings. The community located 25 km from the city centre had significantly lower outdoor concentrations of elements of crustal or traffic origin compared with the two central communities, but had similar levels of long-range transported elements. Significant correlations were found between PM2.5 and most elements outdoors (rs = 0.45-0.90). Copper levels were found to correlate well (rs = 0.64-0.91) to the traffic marker NO2 during both winter and spring in all locations. Copper may be a suitable elemental marker for traffic-related aerosols in health studies in areas without other significant outdoor Cu sources.  相似文献   

20.
持久性有机污染物(POPs)监测是开展履行《关于持久性有机污染物的斯德哥尔摩公约》成效评估的重要内容之一。介绍了履约成效评估POPs监测的要求,综述了我国POPs监测能力建设和履约成效评估全球POPs监测进展。我国自2007年起开展了环境空气、水体和母乳中POPs的监测,所获得的监测数据可为评估我国POPs污染水平和环境与健康风险提供重要的技术支撑。还介绍了国外POPs监测动态,提出借鉴国外经验、建立环境和人体中POPs长效监测机制并开展持续性监测不仅是履约的需求,也可为保护我国生态环境和人体健康提供基础数据。  相似文献   

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