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Occurrence of chlorinated paraffins in house dust samples from Bavaria, Germany
2013
Hilger, B. | Fromme, H. | Völkel, W. | Coelhan, M.
Levels and distribution of chlorinated paraffins were studied in randomly taken house dust samples (<63 μm) from the greater area of Munich, Germany. Quantification of short- (SCCPs, C10–C13) and medium-chain chlorinated paraffins (MCCPs, C14–C16) were performed using gas chromatography electron capture negative ion mass spectrometry (GC–ECNI–MS). Concentrations of MCCPs in private household samples varied between 9 μg/g and 892 μg/g, and exceeded levels of SCCPs, which were in the range of 4–27 μg/g. Two dust samples from a public building contained up to 2050 μg/g SCCPs but no MCCPs. Among MCCPs, chlorinated tetradecanes were major components with a proportion of almost 50%. Among SCCPs, chlorinated dodecanes were usually present at higher concentrations than the congeners of any C10, C11, and C13 chains. The results indicate that particularly MCCPs may be present in relatively high concentrations in house dusts.
显示更多 [+] 显示较少 [-]Quantitation of tetrabromobisphenol-A from dust sampled on consumer electronics by dispersed liquid-liquid microextraction
2013
Tetrabromobisphenol-A (TBBPA) is a brominated flame retardant used worldwide. Despite its widespread use, there are few data concerning environmental concentrations of TBBPA. Thus, the objective of this work was to optimize an ultrasound-assisted dispersed liquid-liquid microextraction (DLLME) method to analyze swabbed surfaces of consumer electronics to determine TBBPA concentrations. Upon sample preparation with DLLME, TBBPA was derivatized with acetic anhydride and then analyzed by gas chromatography–mass spectrometry (GC/MS). Using a 13C12-TBBPA internal standard to improve precision and quantitation, a recovery study was performed. At concentrations of 250–1000 ng/mL, recoveries were 104–106%. Sample preparation with solid phase extraction had comparable recoveries, although overall, improved analyte recovery and precision were achieved with DLLME. In a small survey study, TBBPA concentrations in dust collected from 100 cm2 areas on electronic surfaces (monitor, microwave, refrigerator, and TV) were determined to range from less than the LOQ to 523 ng/mL.
显示更多 [+] 显示较少 [-]Seasonal and spatial variation of trace elements and metals in quasi-ultrafine (PM0.25) particles in the Los Angeles metropolitan area and characterization of their sources
2013
Saffari, Arian | Daher, Nancy | Shafer, Martin M. | Schauer, James J. | Sioutas, Constantinos
Year-long sampling campaign of quasi-ultrafine particles (PM0.25) was conducted at 10 distinct locations across the Los Angeles south coast air basin and concentrations of trace elements and metals were quantified at each site using high-resolution inductively coupled plasma sector field mass spectrometry. In order to characterize sources of trace elements and metals, principal component analysis (PCA) was applied to the dataset. The major sources were identified as road dust (influenced by vehicular emissions as well as re-suspended soil), vehicular abrasion, residual oil combustion, cadmium sources and metal plating. These sources altogether accounted for approximately 85% of the total variance of quasi-ultrafine elemental content. The concentrations of elements originating from source and urban locations generally displayed a decline as we proceeded from the coast to the inland. Occasional concentration peaks in the rural receptor sites were also observed, driven by the dominant westerly/southwesterly wind transporting the particles to the receptor areas.
显示更多 [+] 显示较少 [-]Space and time resolved monitoring of airborne particulate matter in proximity of a traffic roundabout in Sweden
2013
Wilkinson, Kai E. | Lundkvist, Johanna | Netrval, Julia | Eriksson, Mats | Seisenbaeva, Gulaim A. | Kessler, Vadim G.
Concerns over exposure to airborne particulate matter (PM) are on the rise. Currently monitoring of PM is done on the basis of interpolating a mass of PM by volume (μg/m3) but has the drawback of not taking the chemical nature of PM into account. Here we propose a method of collecting PM at its emission source and employing automated analysis with scanning electron microscopy associated with EDS-analysis together with light scattering to discern the chemical composition, size distribution, and time and space resolved structure of PM emissions in a heavily trafficated roundabout in Sweden. Multivariate methods (PCA, ANOVA) indicate that the technogenic marker Fe follows roadside dust in spreading from the road, and depending on time and location of collection, a statistically significant difference can be seen, adding a useful tool to the repertoiré of detailed PM monitoring and risk assessment of local emission sources.
显示更多 [+] 显示较少 [-]Environmental lead exposure risks associated with children's outdoor playgrounds
2013
Taylor, Mark Patrick | Camenzuli, Danielle | Kristensen, Louise Jane | Forbes, Miriam | Zahran, Sammy
This study examines exposure risks associated with lead smelter emissions at children's public playgrounds in Port Pirie, South Australia. Lead and other metal values were measured in air, soil, surface dust and on pre- and post-play hand wipes. Playgrounds closest to the smelter were significantly more lead contaminated compared to those further away (t(27.545) = 3.76; p = .001). Port Pirie post-play hand wipes contained significantly higher lead loadings (maximum hand lead value of 49,432 μg/m2) than pre-play hand wipes (t(27) = 3.57, p = .001). A 1% increase in air lead (μg/m3) was related to a 0.713% increase in lead dust on play surfaces (95% CI, 0.253–1.174), and a 0.612% increase in post-play wipe lead (95% CI, 0.257–0.970). Contaminated dust from smelter emissions is determined as the source and cause of childhood lead poisoning at a rate of approximately one child every third day.
显示更多 [+] 显示较少 [-]A novel in situ method for sampling urban soil dust: Particle size distribution, trace metal concentrations, and stable lead isotopes
2013
Bi, Xiangyang | Liang, Siyuan | Li, Xiangdong
In this study, a novel in situ sampling method was utilized to investigate the concentrations of trace metals and Pb isotope compositions among different particle size fractions in soil dust, bulk surface soil, and corresponding road dust samples collected within an urban environment. The aim of the current study was to evaluate the feasibility of using soil dust samples to determine trace metal contamination and potential risks in urban areas in comparison with related bulk surface soil and road dust. The results of total metal loadings and Pb isotope ratios revealed that soil dust is more sensitive than bulk surface soil to anthropogenic contamination in urban areas. The new in situ method is effective at collecting different particle size fractions of soil dust from the surface of urban soils, and that soil dust is a critical indicator of anthropogenic contamination and potential human exposure in urban settings.
显示更多 [+] 显示较少 [-]Determination of rare earth elements in dust deposited on tree leaves from Greater Cairo using inductively coupled plasma mass spectrometry
2013
Shaltout, Abdallah A. | Khoder, M.I. | El-Abssawy, A.A. | Hassan, S.K. | Borges, Daniel L.G.
This work aims at monitoring the rare earth elements (REEs) and Th in dust deposited on tree leaves collected inside and outside Greater Cairo (GC), Egypt. Inductively coupled plasma mass spectrometry (ICP-MS) was employed. The concentration of REEs in the collected dust samples was found to be in the range from 1 to 60 μg g−1. The highest concentration of REEs was found in dust samples collected outside GC, in the middle of the Nile Delta. This would refer to the availability of black sands, due to desert wind occurrence during the sample collection, and anthropogenic activities. The limits of detection of the REEs ranged from 0.02 ng g−1 for Tm to 3 ng g−1 for Yb. There was an obvious variation in the concentration of REEs inside and outside GC due to variations of natural and anthropogenic sources. Strong correlations among all the REEs were found.
显示更多 [+] 显示较少 [-]Soil humic-like organic compounds in prescribed fire emissions using nuclear magnetic resonance spectroscopy
2013
Chalbot, M.-C. | Nikolich, G. | Etyemezian, V. | Dubois, D.W. | King, J. | Shafer, D. | Gamboa da Costa, G. | Hinton, J.F. | Kavouras, I.G.
Here we present the chemical characterization of the water-soluble organic carbon fraction of atmospheric aerosol collected during a prescribed fire burn in relation to soil organic matter and biomass combustion. Using nuclear magnetic resonance spectroscopy, we observed that humic-like substances in fire emissions have been associated with soil organic matter rather than biomass. Using a chemical mass balance model, we estimated that soil organic matter may contribute up to 41% of organic hydrogen and up to 27% of water-soluble organic carbon in fire emissions. Dust particles, when mixed with fresh combustion emissions, substantially enhances the atmospheric oxidative capacity, particle formation and microphysical properties of clouds influencing the climatic responses of atmospheric aeroso. Owing to the large emissions of combustion aerosol during fires, the release of dust particles from soil surfaces that are subjected to intense heating and shear stress has, so far, been lacking.
显示更多 [+] 显示较少 [-]Distributions, sources and pollution status of 17 trace metal/metalloids in the street dust of a heavily industrialized city of central China
2013
Li, Zhonggen | Feng, Xinbin | Li, Guanghui | Bi, Xiangyang | Zhu, Jianming | Qin, Haibo | Dai, Zhihui | Liu, Jinling | Li, Qiuhua | Sun, Guangyi
A series of representative street dust samples were collected from a heavily industrialized city, Zhuzhou, in central China, with the aim to investigate the spatial distribution and pollution status of 17 trace metal/metalloid elements. Concentrations of twelve elements (Pb, Zn, Cu, Cd, Hg, As, Sb, In, Bi, Tl, Ag and Ga) were distinctly amplified by atmospheric deposition resulting from a large scale Pb/Zn smelter located in the northwest fringe of the city, and followed a declining trend towards the city center. Three metals (W, Mo and Co) were enriched in samples very close to a hard alloy manufacturing plant, while Ni and Cr appeared to derive predominantly from natural sources. Other industries and traffic had neglectable effects on the accumulation of observed elements. Cd, In, Zn, Ag and Pb were the five metal/metalloids with highest pollution levels and the northwestern part of city is especially affected by heavy metal pollution.
显示更多 [+] 显示较少 [-]Chemical composition, diurnal variation and sources of PM2.5 at two industrial sites of South China
2013
Huang, Bo | Liu, Ming | Ren, Zhaofang | Bi, Xinhui | Zhang, Guohua | Sheng, Guoying | Fu, Jiamo
Diurnal PM2.5 samples were collected during summer and winter at an industrial complex site (site A) and an electronic waste (e–waste) recycling site (site B) in Qingyuan, South China. The concentration of organic carbon (OC), elemental carbon (EC), water soluble ions (WSI) and elements were investigated for their seasonal and diurnal variations. Organic matter (OM) was the most abundant specie in winter, accounting for 40.2% and 48.8% of PM2.5 in sites A and B, respectively; while in summer, excluding the elemental portion, WSI was the biggest part, which accounted for 37% and 49.4% of PM2.5 mass in sites A and B, respectively. Significantly higher concentrations were observed for most of the analyzed chemical species in winter. Average acidity of PM2.5 at both sites was significantly higher in summer. Diurnal variation with elevated concentrations of PM2.5 in nighttime samples was found at site B. Secondary inorganic aerosols (NH4+, NO3− and SO42−) exhibited clear day–to–night variation. Concentration of SO42− was about 15% higher in daytime samples. NH4+ and NO3− co–varied in winter, but were weakly associated with each other in summer. Sites A and B samples were almost all ammonium–rich in winter, whereas the summer samples were ammonium–poor during the daytime but ammonium–rich in the night. Positive matrix factorization (PMF) model analysis showed that secondary formation, biomass burning, regional industries, coal combustion and dust had significant contribution to PM2.5. Among them, secondary formation and biomass burning together contributed approximately 50% of PM2.5 mass at both sites. Additionally e–waste recycling activities resulted in high pollution of Cu at Site B.
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