首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
A program of house dust sample collection and analysis has begun in Syracuse,New York, USA, in order to determine the feasibility of a geography-based exposure assessment for urban metals. The sampling program, and the protocols it employs, is described for two different types of wipe media, Ghost Wipes and Whatman Filters. Preliminary results show that strong spatial patterns of floor dust loading (mg dust per square foot) can be observed for data aggregated at a spatial scale of about 1600 m (~2.5 kin2). Floor dust metal concentrations were similar to those found in other urban environments, with some regional variation. The median floor dust Pb concentration was ~108 mg· kg-1 for this initial data set of ~264 sampled residential locations, and varied from 50 to 1100 mg Pb · kg-1.  相似文献   

2.
This study describes a comparison of worker exposure to total and inhalable dust, inorganic As, and borates using two types of particulate sampling assemblies as part of a comprehensive industrial hygiene evaluation in a borate mining and processing facility. Employees were segmented into similar exposure groups (SEG) based on work location within the facility, job classification, and type of chemical agent. Approximately 10% of the employees from each SEG wore two personal sampling devices simultaneously for the purpose of collecting total and inhalable particulate fractions using a closed face, 37-mm mixed cellulose ester matched-weight filters (MMW), and Institute of Occupational Medicine (IOM) sampling assembly. Sample results indicated that the IOM concentrations were consistently higher than the corresponding MMW concentrations for all three agents. An analysis was performed to investigate a relationship between MMW and IOM. The data revealed correlation coefficient values of 0.72, 0.82, and 0.84 for total dust (n = 197), inorganic As (n = 137), and borates (n = 194), respectively. These positive correlation coefficients indicate that the IOM and MMW measurements are consistent with each other, and can be used for predicting exposure levels. The total dust and borate large mean ratios should be considered in developing inhalable fraction-based regulatory standards.  相似文献   

3.
北京市8种常绿阔叶树种滞尘能力   总被引:1,自引:0,他引:1  
范舒欣  蔡妤  董丽 《生态学杂志》2017,28(2):408-414
为筛选适用于北京地区的具有优良滞尘能力的常绿阔叶型绿化树种,提高城市植被滞尘能力,选取北京地区园林绿化应用广泛的8种常绿(含半常绿)阔叶绿化树种,应用洗脱-质量差值法,于2014年冬、春季节对其单位叶面积滞尘量进行测定,计算单叶滞尘量和单株滞尘量,并对树种综合滞尘能力进行聚类分析.结果表明: 小叶黄杨、冬青卫矛、小叶女贞、金叶女贞、胶东卫矛、箬竹、早园竹和黄槽竹8种主要常绿(含半常绿)阔叶树种的滞尘能力存在较大差异,冬青卫矛具有最大的单位叶面积与单株滞尘能力,为1.36 g·m-2和59.63 g·plant-1,而箬竹的单叶滞尘能力最强(1.62 mg·leaf-1).选择不同的滞尘量计量单位,树种滞尘量排序会发生变化.对8种常绿(含半常绿)阔叶树种做基于多指标综合滞尘能力的聚类分析可得到相应的分类,各类别代表不同级别的综合滞尘能力水平.其中,冬青卫矛、早园竹的综合滞尘能力较优良,而小叶黄杨、金叶女贞和黄槽竹的综合滞尘能力较弱.  相似文献   

4.
ABSTRACT. Occurrence of Acanthamoeba in the hospital environment may represent a health risk for patients, since these organisms can cause severe opportunistic illness, such as keratitis, and also can harbor pathogenic agents. We analyzed the dust from some environments of a public hospital in Curitiba, Parana State, Brazil. Two distinct populations of Acanthamoeba were isolated in five locations and morphologically classified as group I and group II according to Pussard and Pons. Isolates were identified as Acanthamoeba by PCR using primers to amplify a region of 18S rDNA, which showed variation in the product length among the isolates. A cloned culture of group II showed greater growth at 37 °C and in media with 0.1, 0.5, and 1.0 M mannitol, which are the physiological characteristics of pathogenic Acanthamoeba . Monitoring the presence of Acanthamoeba in hospital units, as well as evaluating the pathogenicity of the isolates, can be an approach to alert the health professionals to improve the disinfection procedures and minimize the risks of treating this problematic disease caused by this protozoan.  相似文献   

5.
Fungi inhabiting household environments in the West, East and Central localities of Riyadh city were screened. The screened area included bedrooms, drawing rooms, living rooms, kitchens and bathrooms. The common genera of fungi isolated wereAlternaria, Aspergillus, Cercospora, Chaetomium, Cladosporium, Curvularia, Drechslera, Embellisia, Fusarium, Mucor, Penicillium, Rhizopus, Scytalidium, Trichoderma, Torula andUlocladium. Two uncommon generaNodulosporium andOidiodendron for Saudi Arabian mycoflora were also isolated. In all the localities, the highest number of fungal colonies per plate or per gram were found in the living rooms, followed by bedrooms. The number of colonies per plate or per gram was in general higher in densely populated than in less populated areas.  相似文献   

6.
Street dust samples from urban and suburban areas were collected from the city of Karak, Jordan, during the summer season of 2004. Samples were analyzed for their heavy metal concentrations (Pb, Cu, Zn, Ni, Fe, Cr, Cd, and Mn). The results showed that all heavy metals are higher in city urban areas than the surrounding suburbs. The distribution and concentrations of heavy metals in all areas show automobile originated sources such as emissions and wear and tear of automobiles were the main source of pollution. Despite the fact that the city of Karak and the capital Amman are under the same climatic conditions and same type of fuel used in both cities, the heavy metal concentrations of street dust samples were lower in Karak than Amman due to the lower traffic density.  相似文献   

7.
Environmental health is an essential component of quality of life in modern societies. Foliar dust contains polycyclic aromatic hydrocarbons (PAHs) that may have harmful effects on human health. The PAHs concentration of foliar dust is useful to assess environmental air pollution. Our results indicate that: (1) the highest levels of PAHs were distributed in urban areas, with a mean of 3430.23 ng·g?1, lower mean concentrations were found in suburban (2282.12 ng·g?1), and rural areas (1671.06 ng·g?1). (2) Diagnostic ratios and principal component analysis were used to identify the sources of PAHs: Gasoline vehicle traffic emissions were the predominant source in urban areas, along with coal and coke combustion. In suburban areas, the main sources were petroleum combustion (especially liquid fossil fuels) and coal combustion. Coal and wood combustion were the primary source of PAHs in foliar dust in rural areas. (3) The incremental lifetime cancer risk (ILCR), estimated based on the results of this study indicate that urban residents were potentially exposed to high cancer risk via both dust ingestion and dermal contact. We conclude that urbanization has significant effects on the PAH concentrations of foliar dust, illustrating the importance of trees in improving air quality in urban areas.  相似文献   

8.
A study was carried out on suspended dust, bacterial and fungal aerosols in a four-storey flourmill building located in Giza, Egypt. Airborne microorganisms were quantitatively isolated using liquid impinger and gravimetric samplers during the period from March 2004 to February 2005. Suspended dust varied from 1.96 to 16.3 mg m−3 and 0.69 to 1.8 mg m−3 in the indoor and outdoor environments, respectively. Suspended dust was significantly greater (P < 0.05) at bran package, double roller, purifiers and flour storage units in comparison to the outdoor reference site. The dust levels exceed the occupational exposure limit (OEL) of 0.5 mg m−3 for flour dust. Airborne microbial counts were found at median values, between sampling locations, ranged from 0 to >104 CFU m−3. Gram-negative bacteria were found in small numbers (0–102 CFU m−3). The highest concentration of actinomycetes (>103 CFU m−3) was detected in the storage unit. Airborne fungal counts were found at the median values, between sampling locations, varied from 103 to 104 CFU m−3. The counts of airborne bacteria and fungi were significantly greater (P < 0.05) at the purifiers and double roller mill units in comparison to the outdoor reference site using the liquid impinger sampler. Microbial levels associated with bulk deposited dust averaged between 105 and 106 CFU g−1. Alcaligenes (5.4%) Pseudomonas (3.87%) and Enterobacter (3.1%) were the predominant Gram-negative species while Bacillus (29.4%) and Micrococci (13.9%) were the major components of Gram-positive bacteria. Aspergillus and Penicillium were the predominant fungal types indoor whereas Cladosporium (35.2%) and Aspergillus species (22.2%) were the predominant fungal types outdoor. A number of allergenic and toxigenic bioaerosols were found in the flourmill workplace.  相似文献   

9.
To provide more insight into the removal ability of urban air dust and associated metals by plant leaves, and thus guide urban green planning to improve air quality, 15 plant species leaves collected from Beijing roadside were analyzed for size fractions of leaf surface dust (SD) and inner wax dust (WD). Seven associated metals Cd, Cr, Cu, Fe, Mn, Pb and Zn were also measured. Metal Accumulation Index (MAI) was calculated for different species leaves at various dust sizes and soluble forms, respectively. Cluster analysis was used for the plant species and correlations between dust and metal concentrations and for inter-metal concentrations were calculated for both surface and inner wax dust. Mean leaf total dust TD (SD?+?WD), SD and WD were measured as 1159, 817 and 342?mg m?2, respectively, with the highest values observed all in Euonymus japonicus. Most species leaves collected larger ratios of SD than WD except Salix babylonica and Robinia pseudoacacia. While SD was presented at all particle size fractions for all plants, nearly all species leaves collected higher proportions of WD >10?µm. Mean metal levels of leaf TD of all species ranged from high to low as Fe?>?Cr?>?Zn?>?Pb?>?Cu?>?Mn?>?Cd, but with different orders for individual species. Metals were observed in all sizes of SD/WD, although the size distributions were various for certain metals. Intercorrelations of metal concentrations in leaf SD/WD were positively significant except Pb, which may have different emission sources. Species Prunus cerasifera f. atropurpurea, Syringa oblata, Malus micromalu, Koelreuteria paniculata and Robinia pseudoacacia may possess better overall metal collection ability due to their relatively higher MAI values, but species Euonymus japonicus, Malus micromalu, Ligustrum x vicaryi and Koelreuteria paniculata were identified as the best choices in removing air dust based on cluster analysis and suggested to be planted at heavy trafficked road site for air quality improvement.  相似文献   

10.
The relationships between metal contents in soil, road dust, and rice, and in human hair from a rural area of China were observed for Cr, Cu, Mn, Ni, Pb, and Zn. The results showed that the mean concentrations of Mn in human hair were higher than the highest reference value. The concentrations of Cr, Cu, Ni, and Zn in soil and road dust were usually higher than their background values. The enrichment factors indicated that the determined metals in soil and road dust were usually derived from natural sources. Chromium, Pb, and Zn in soils and road dusts from several sites were slightly influenced by anthropogenic sources. The regression analyses showed that positive relationships usually exist between the concentrations of the determined metals in rice and in human hair as well as in soil and in human hair. However, relationships between metal concentrations in road dust and in human hair were less obvious. The study demonstrated that human hair was an applicable biomonitor of metal concentrations in rice, soil, and road dust from a rural area in China. Metal concentrations in local human hair could be used to predict contamination levels of metals in rice and soil.  相似文献   

11.
Abstract

A total of 83 dust samples were collected from the streets of Urumqi city in NW China and analyzed for the concentrations of As, Cd, Cr, Cu, Hg, Mn, Ni, Pb, and Zn elements. The spatial distribution, contamination levels, main sources, and potential health risks of these trace elements were determined based on geostatistical analysis, geo-accumulation index, multivariate analysis, and the health risk assessment model introduced by the USEPA, respectively. The obtained results indicate that the average concentrations of Cd, Cr, Cu, Hg, Ni, Pb, and Zn exceed the corresponding background values determined in Xinjiang soils by factors of 2.0, 1.35, 1.38, 8.24, 1.28, 2.09, and 3.26, respectively. The spatial distribution patterns of the nine trace elements in street dust were found to be substantially heterogeneous, and the contamination level decreased in the following order: Hg?>?Zn?>?Pb?>?Cd?>?Cr?>?Cu?>?As?>?Ni?>?Mn. Based on the identified concentrations, the collected dust samples were found to be moderately polluted by Hg, and not polluted by As, Cr, Cu, Mn, and Ni. The remaining elements, Cd, Pb, and Zn lie on the borderline between non-pollution and moderate pollution levels. Furthermore, it was shown that Mn and Zn in street dusts originate from both, natural and anthropogenic sources, while As, Cd, Cr, Cu, Hg, Ni, and Pb are mainly produced by anthropogenic sources. Overall, the carcinogenic and non-carcinogenic health risks of the analyzed elements, instigated primarily by oral ingestion of street dusts, were found to be within the acceptable range for both, children and adults. As and Cr are the main non-carcinogenic elements, whereas Cr is the major carcinogenic element among the investigated dust-bound metals in the study area.  相似文献   

12.
13.
Twenty-one street dust samples were collected from the urban sites in Baoding, China, to investigate the species and bioavailabilty of arsenic in them. The ecological risk and bioavailability of arsenic were evaluated using three models including Bioavailability Factor (BF), Contamination Factors (Cf)and Geoaccumulation Index model (Igeo). The species of arsenic in the dust samples were analyzed using an optimized BCR sequential extraction method. The total concentrations of As in the street dust samples ranged from 13.16 mg kg?1 to 67.26 mg kg?1. Geoaccumulation index (Igeo) of As ranged from 0.28 to 1.99. The speciation analysis indicated that As in the street dust samples were mainly in the residual fraction (F4), and the proportion ranged from 84.35% to 87.07%. Moreover, the ranges of the BF and Cf were 0.650–0.129 and 0.119–0.186, respectively. The results indicated that arsenic contained in the street dust samples was with low bioavailability.  相似文献   

14.
水泥粉尘污染对水稻,油菜和土壤环境的影响   总被引:3,自引:0,他引:3  
通过在水泥厂周围布设不同监测样点、样田,了解水泥粉尘沉降对水稻、油菜和土壤环境的影响。结果表明,水泥厂周围的大气环境受到不同程度的粉尘污染。水泥粉尘使一些农田水稻和油菜产量有所下降,但对质量未产生不良影响,水泥粉尘会使土壤中钙的含量明显增加。  相似文献   

15.
α-Acaridial [2(E)-(4-methyl-3-pentenyl)butenedial] is a novel monoterpene secreted from the house dust mites. Because of its molecular nature of a highly reactive, small lipidic compound, we addressed whether α-acaridial might function as a haptenic allergen that induced allergic contact dermatitis. Mice sensitized with α-acaridial were challenged by the same antigen on the ear skin. After 2 days, significant ear swelling with a prominent infiltration of CD4+ T lymphocytes was observed. In vitro, α-acaridial exhibited an outstanding ability to quickly interact with and chemically modify a reference protein. Virtually all cysteine residues and a sizable fraction of lysine residues were found to be selectively modified, suggesting that α-acaridial could potentially interact with any proteins. Previously, numerous mite-derived proteinaceous allergens have been associated with contact dermatitis. Our study now emphasizes that small lipidic compounds released from mites comprise a new class of mite allergens, and therefore, is of significant medical implications.  相似文献   

16.
Abstract

To understand distribution, toxicity, and health risk assessment of Cu, Ni, Cr, Pb, Zn, Fe, and Mn, 33 surface dust samples were collected during June 2015 from Bhiwadi Industrial Area (BIA) in north India. Average metal concentrations exceeded their corresponding values in upper continental crust depending upon metal(s) and sampling site(s). Industrial emissions resulted in high contamination factors and high pollution load index for metals. The BIA falls under least to moderately for Mn, unpolluted to heavily and extremely for Ni and Cu, Pb, and Zn and moderately to extremely polluted region for Cr. Inter-metal correlations and PCA indicated common and mixed sources for metals such Ni–Cr electroplating and alloys, battery recycling, stainless-steel, electrical wires, galvanizing, vehicular emissions, and wear and tear of vehicle parts. Non-carcinogenic health risk due to metals in surface dust was high in children compared to adults and major pathways were ingestion followed by dermal and inhalation. Surface dust in BIA falls under hazardous category as metals leached in toxicity characteristics leaching procedure and waste extraction test exceeded their prescribed regulatory limits. Leaching of metals can cause contamination of surface water, groundwater, and soils in surrounding areas, and can pose risk to human health and ecology.  相似文献   

17.
Abstract

In this study, the concentrations and health risks of heavy metals (Cu, Pb, Zn, Ni, Co, Cd, and Cr) in indoor dust are investigated in the vicinity of the Xinqiao mining area, Tongling, China. Results indicate that heavy metals except Co were clearly enriched in indoor dust. Especially Cd was extremely enriched, followed by Zn, Cu, and Pb. However, no significant regional differences (p?>?0.05) were found in other elemental contents aside from Cu. Statistical analysis revealed that metal elements except Co were presumed to originate primarily from mining activities. Health risk assessment indicated that the hazard quotients and hazard indices of all studied metal elements were less than 1 and thus posed no potential noncancer health risks to adults and children. Moreover, the cancer risks of Ni, Cr, Cd, and Co were within acceptable ranges, implying no cancer risk to local residents; however, the noncarcinogenic risk of Pb and the carcinogenic risk of Cr and Cd warrant close attention.  相似文献   

18.
Concentrations of Pb and Cd in different size fractions in road dust samples taken from areas of high traffic flows in two streets in Irbid City, Jordan, have been measured using graphite furnace atomic absorption spectrometry (GFAAS). A series of road dust particles in the following size ranges, < 90, 90–106, 106–125, 125–250, 250–1000 and 1000-2000 μ m, were investigated to evaluate the ratio between metal content in each fraction of particle size and total metal content. Results show most of the highest levels were found in the small particle sizes. Sequential extraction procedure was used for chemical speciation in road dust samples of < 90 μ m. Two standard reference materials, CRM142R and SRM 2709, were analyzed to assess the accuracy and the reliability of the proposed method, and the precision of the results was expressed by relative standard deviation (rsd < 6%).  相似文献   

19.
Byssinosis is a disabling occupational lung disease caused by cotton dust. It is a well-known occupational respiratory disease in cotton industry workers caused by cotton dust pollution. Many studies have been documented the effects of cotton dust on pulmonary function among workers employed in cotton-spinning mills. However, little data exist on the prevalence of this disorder in female workers particularly in western part of India. The present study was conducted to analyze the effects of exposure to cotton dust on pulmonary functions among female workers. The study was designed to assess the effects of exposure to cotton dust on lung functions among female cotton industry workers. Study group comprises 50 Female workers of cotton industry and control group comprises 50 age matched females who were neither worked in cotton industry nor exposed to cotton dust. Information was collected using standardized questionnaires, physical examination and spirometric measurements. Student''s T test was used to find the difference between spirometric parameters. All the respiratory parameters (FVC, FEV1, FEV1/FVC ratio, FEF 25-75 % PEFR and MVV) were reduced in cotton industry workers as compared with control subjects (p<0.0001) and no significant difference of SpO2 between groups. Cotton dust exposure makes huge impact on respiratory parameters of the cotton industry workers. This deterioration in respiratory health deteriorates with increasing duration of exposure. The health hazards caused by cotton dust should be controlled by creating awareness among the workers & employers.  相似文献   

20.
北京市26种落叶阔叶绿化树种的滞尘能力   总被引:2,自引:0,他引:2       下载免费PDF全文
为筛选适用于北京市的具有优良滞尘能力的绿化物种, 提高城市植被滞尘效应, 选取北京市园林绿化应用最广泛的26种落叶阔叶树种, 应用质量差值法, 于2014年夏季对不同树种单位叶面积滞尘量进行测定, 计算单叶滞尘量与单株滞尘量, 并对树种滞尘能力进行了相应的聚类分析。结果表明: 不同树种间滞尘能力存在较大差异, 选择不同的滞尘量计量单位, 树种滞尘量排序会相应地发生变化。对26种北京市常用落叶阔叶树种从叶片、植株与综合滞尘能力三个方面的聚类分析均可得到相应的分类, 各类别代表不同级别的滞尘能力水平。研究分析认为, 植物滞尘能力与其叶表特征、滞尘方式、株型结构、整株叶量及所处环境含尘量等密切相关, 评价树种滞尘能力时应进行综合考虑。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号