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ABSTRACT: Heavy metals and persistent organic pollutants polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) were analyzed in 34 surface soil samples collected from farmland and 7 soil or dust samples collected from the workshops in South China, where e-waste was dismantled using primitive techniques. The results show that Cd, Cu and Hg were the most abundant metals, in particular Cd pollution was serious in farmland soils, and the median concentrations in farmland soils were beyond the environmental quality standard for soils (China Grade II). A correlation between Cd, Cu, Zn, Pb and PCBs or PBDEs was significant indicating similar sources. Among the PCB congeners, high relative similarity was observed between the e-waste dump site soil (EW1) and Aroclor 1254, implying that the technical product Aroclor 1254 was one of the major sources of PCB contamination. High concentrations of PCBs in workshop dusts (D2 and D3) (1958 and 1675 μg kg(-1)) demonstrated that the workshops dismantling electrical wires and cables, electrical motors, compressors and aluminum apparatus containing PCBs in lubricants represent strong PCB emission sources to this area. Principal component analysis (PCA) and PBDE homologue patterns verify that farmland soils surrounding the e-waste recycling sites were enriched with lower brominated congeners, and the major source of PBDEs in dust samples might potentially be associated with the extensive use of deca-mix technical products as a flame retardant. The difference between e-waste soils, dusts and farmland soils can be observed in the PCA score plot of PCBs and PBDEs, and E-waste soils and dusts exhibited more diversity than farmland soils. Furthermore, a prediction of the particular kinds of pollution from different recycling activities through the analysis of each contamination and the connections between them was investigated.
Environmental science. Processes & impacts. 04/2013;
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ABSTRACT: The hydroxylated PBDEs (OH-PBDEs) and brominated phenolic compounds in aerosol samples from a printed circuit boards recycling workshop were characterized. The results show that OH-PBDEs, which are naturally occurring compounds or metabolism of PBDEs, could also be emitted from the e-waste recycling. Five OH-PBDEs, several unidentified mono-OH-PBDE and di-OH-PBDE congeners were detected. The concentration of ∑OH-PBDEs was 1.74-4.22 ng m-3 (average of 2.66 ng m-3), with 6-OH-BDE-47 (0.329 ng m-3) as the most abundant identified congener. The total concentration of di- to tri-brominated phenols (BPs) was 18.8-32.0 ng m-3 (average of 26.3 ng m-3) with 2,4,6-triBP as the most abundant congener. These findings suggest that the recycling of printed circuit boards represent a strong source of OH-PBDEs and BPs to the atmosphere. Additionally, some phenolic compounds including brominated bisphenol A, hydroxylated polybrominated biphenyl species and etc. were also identified.
Environmental pollution (Barking, Essex: 1987) 03/2013; 177C:71-77. · 3.43 Impact Factor
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ABSTRACT: The total suspended particles (TSP) collected during 2002 to 2003 in Wushan district and Liwan district in Guangzhou were
analyzed for the saccharide compositions using gas chromatography-mass spectrometry (GC/MS) and N,O-bis-(trimethylsilye)trifluoroacetamide
(BSTFA) derivatization. The results showed that the saccharides were composed of anhydrosaccharides consisting of levoglucosan,
mannosan, galactosan and 1,6-anhydro-β-glucofuranose, and primary saccharides with sucrose as the most abundant, followed
by α-and β-glucose, α-and β-fructose, mycose, and saccharide polyols. The highest saccharide levels occurred in autumn. The
anhydrosaccharides came from biomass burning, whereas primary saccharides were the result of resuspention of surface soil
dust associated with the agricultural activities and the decay of the falling leaves.
Chinese Science Bulletin 04/2012; 54(23):4500-4506. · 1.32 Impact Factor
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ABSTRACT: Daytime and nighttime PM(2.5) samples were collected between August 5 and 16, 2009 and between January 24 and February 4, 2010 in an industrial complex site (site A) and an electronic waste recycling site (site B) to determine the seasonal and diurnal variations of 19 individual polycyclic aromatic hydrocarbons (PAHs) with molecular weight 302 (MW302) including four highly carcinogenic dibenzopyrene (DBP) isomers dibenzo[a,l]pyrene (DBalP), dibenzo[a,e]pyrene (DBaeP), dibenzo[a,i]pyrene (DBaiP), and dibenzo[a,h]pyrene (DBahP). This is the first report on DBP isomers in air particles from South China. The total concentration of PAH MW302 isomers ranged from 1.65 to 3.60 ng m(-3) in summer and 3.82 to 9.81 ng m(-3) in winter. The strongest peaks in the chromatograms of the MW302 isomers were naphtha[2,1-a]pyrene (N21aP), dibenzo[j,l]fluoranthene (DBjlF), naphtha[1,2-b]fluoranthene (N12bF), naphtha[1,2-k]fluoranthene (N12kF) and dibenzo[a,e]fluoranthene (DBaeF), constituting 52.0 to 55.4% of the total MW302 isomers. All the MW302 isomers showed notable seasonal variations. Most of the MW302 isomers in site B showed distinctive diurnal variations with higher concentrations occurring in the night. Taking into account both concentration and potency equivalence factors (PEFs), the strongest carcinogen in the analyzed samples was DBaiP, and the ratios of sum carcinogenic potency of four highly carcinogenic DBP isomers to benzo[a]pyrene (BaP) was about 0.94 in winter to 1.89 in summer, indicating the importance of DBP isomers for the risk assessment. Health risk assessment indicated that on average, 1 in 100 000 residents in the two industrial sites may have an increased risk of cancer due to PAH exposure.
Journal of Environmental Monitoring 07/2011; 13(9):2568-74. · 1.99 Impact Factor
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ABSTRACT: The daytime and nighttime air samples were collected from an e-waste recycling site in Guiyu (GY) and its upwind and downwind direction sites in Chendian (CD) and Gurao (GR), respectively, during September and December 2005 to determine the phase partitioning, seasonal and diurnal variation of polybrominated diphenyl ethers (PBDEs). The three sites showed similar congener compositions with BDEs-28, -47, -99, -207 and -209 as the dominant congeners. The gas phase contribution ranged from 42.1% ± 17.1% of the total PBDEs in summer to 9.0% ± 8.6% in winter. Partitioning of PBDEs between gas and particulate phases was well correlated with the subcooled liquid vapor pressure (P(L)(0)) for all samples. Both Junge-Pankow adsorption model and K(OA)-based absorption model fitted well the PBDEs data in winter but overestimated the sorption of PBDEs in summer. The mean atmospheric concentrations of BDEs-47 (2748 pg m(-3) in summer and 6146 pg m(-3) in winter) and -99 (1656 pg m(-3) in summer and 4911 pg m(-3) in winter) in GY were much higher than those from other places around the world. Additionally, the time series of PBDEs in GY demonstrated a pronounced diurnal variation pattern, but not CD and GR, where PBDEs appeared partly associated with regional accumulation. Source characterization from local emissions may be the major factor controlling the diurnal variation of PBDEs in GY air. The risk assessment showed that the total daily intakes of BDE-99 in GY was 9.0-34.9 ng kg(-1)-bwd(-1), which is higher than the maximal allowed intake level (0.26 ng kg(-1)-bwd(-1)) with factors of 35-135, indicating possible health risk for GY residents with exposure to PBDEs.
Chemosphere 02/2011; 82(9):1246-52. · 3.21 Impact Factor
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ABSTRACT: Exposure of young mothers and newborns to organochlorine pesticides (OCPs) were assessed by measuring the levels of OCPs in human milk (HM) and maternal blood (MB) and umbilical cord blood (UCB) samples from Guangzou in China. 21 OCPs were analyzed using gas chromatography/mass spectrometry (GC/MS). The results showed that the median levels (ranges) of total HCHs (four HCH isomers) in HM, MB and UBC were 54.7 (5.7-159.3), 43.7 (1.9-386.6), and 20.2 (4.0-103.2) ng/g lipid, respectively; and the median concentration of total DDTs (DDT and its metabolites) were 2114.6 (329.1-6164.6), 1676.0(283.4-6167.7), and 1287.8(189.6-3296.0) ng/g lipid, respectively. On a lipid basis, the chemical concentrations were in the order HM>MB>UCB. Comparison with literature data showed that the levels of summation operatorDTTs and summation operatorHCHs in milk and maternal blood samples were within the range reported in samples in other Chinese provinces and higher than those in developed or industrialized countries, but significantly lower than contaminated area such as in India. The predominant pollutant in the HCH family is beta-HCH. p,p'-DDE is a predominant pollutant in all DDEs and DDDs and DDTs for all the samples tested, and accounted for more than 80% of total HCHs and DDTs.
Science of The Total Environment 07/2010; 408(16):3133-8. · 3.29 Impact Factor
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ABSTRACT: Isoprene is one of the most important non-methane hydrocarbons (NMHCs) in the troposphere: it is a significant precursor of O(3) and it affects the oxidative state of the atmosphere. The diastereoisomeric 2-methyltetrols, 2-methylthreitol and 2-methylerythritol, are marker compounds of the photooxidation products of atmospheric isoprene. In order to obtain valuable information on the delta(13)C value of isoprene in the atmosphere, the stable carbon isotopic compositions of the 2-methyltetrols in ambient aerosols were investigated. The 2-methyltetrols were extracted from filter samples and derivatized with methylboronic acid, and the delta(13)C values of the methylboronate derivatives were determined by gas chromatography/combustion/isotope ratio mass spectrometry (GC/C/IRMS). The delta(13)C values of the 2-methyltetrols were then calculated through a simple mass balance equation between the 2-methyltetrols, methylboronic acid and the methylboronates. The delta(13)C values of the 2-methyltetrols in aerosol samples collected at the Changbai Mountain Nature Reserves in eastern China were found to be -24.66 +/- 0.90 per thousand and -24.53 +/- 1.08 per thousand for 2-methylerythritol and 2-methylthreitol, respectively. Based on the measured isotopic composition of the 2-methyltetrols, the average delta(13)C value of atmospheric isoprene is inferred to be close to or slightly heavier than -24.66 per thousand at the collection site during the sampling period.
Rapid Communications in Mass Spectrometry 06/2010; 24(11):1625-8. · 2.79 Impact Factor
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ABSTRACT: Diurnal air samples were collected from the E-waste dismantling region Guiyu and the underwear industry region Chendian. This was the first report to present the diurnal variation of PBDEs in the atmosphere. The average concentrations of 11 PBDE congeners were 11,742 pgm(-3) in the daytime, and 4830 pgm(-3) at night in Guiyu, while the concentrations were lower in Chendian with 376 pgm(-3) in the daytime, and 237 pgm(-3) at night. BDE-209 accounted for 22% and 31.3% of the total PBDEs in Guiyu and Chendian, respectively. The diurnal variation trends of BDE-47, -99, -153, -183, and -209 were also analyzed in detail in the two regions.
Environmental pollution (Barking, Essex: 1987) 01/2009; 157(3):1051-7. · 3.43 Impact Factor
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ABSTRACT: Assessment of virus aerosol characteristics is important in designing methods for controlling infectious virus aerosols. The factors relevant to aerosol characteristics include aerosol particle size, concentration, infectivity and virulence. To investigate these characteristics and their changes in different environmental conditions, a laboratory model is required. In this study, replication-deficient recombinant adenovirus (RDRADS) encoding green fluorescent protein (GFP) was used as a model virus. Model virus aerosols were generated using a TK-3 aerosol generator attached to a chamber which could simulate different environmental conditions. Virus aerosol specimens were collected with an FA-1 six-stage impact sampler. The relative genome copy number of viruses in the aerosol was determined by real-time fluorescence quantitative PCR. The number of virus-infected PK15 (pig kidney) cells was determined by counting cells with green fluorescence under a fluorescence microscope at 48 h post-inoculation. Fifteen experiments in different conditions were performed. We found that the viral DNA was present in stages 4-6 of the sampler, with the peak value at stage 5, corresponding to aerosols with a particle size of 0.65-3.3 mum. PK15 cells with green fluorescence showed the same size distribution range at temperatures >29 degrees C and above, where no green fluorescent cells were found, while the genome copy number assayed by real-time PCR remained unchanged. In the presence of high concentrations of particulate matter created by burning biomass, the peak value of virus genome copy number and green fluorescent cell counts shifted to stage 4 of the sampler, corresponding to aerosols with a particle size of 2.1-3.3 mum. The results provide evidence that viruses are present in the atmosphere as aerosols, which are much larger than their own particle size, and that the viruses in the aerosols are affected by atmospheric conditions. Our laboratory model was shown to be feasible for investigating the relationship between the characteristics of viruses and atmospheric conditions.
Journal of Medical Microbiology 11/2008; 57(Pt 11):1335-9. · 2.50 Impact Factor
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Jing Yuan,
Lan Chen,
Duohong Chen,
Huan Guo, Xinhui Bi,
Ying Ju,
Pu Jiang,
Jibin Shi,
Zhiqiang Yu,
Jin Yang,
Liping Li,
Qi Jiang,
Guoying Sheng,
Jiamo Fu,
Tangchun Wu,
Xuemin Chen
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ABSTRACT: In this study, we recruited 49 subjects from one village close to an electronic waste (e-waste) site (exposed group) and another located 50 km away from the e-waste site (control group). We found that serum levels of polybrominated diphenyl ethers (median PBDEs, 382 ng/g lipid weight; range, 77-8452 ng/g lipid weight) and thyroid-stimulating hormone (median TSH, 1.79 microIU/mL; range, 0.38-9.03 microIU/mL) and frequencies of micro-nucleated binucleated cells (MNed BNC; median, 5% per hundred; range, 0-96% per hundred) were significantly higher in the exposed group than in the control group (158 ng/g, range of 18-436 ng/g, and p < 0.05; 1.15 microIU/mL, range of 0.48-2.09, and p < 0.01; and 0% per hundred, range of 0-5% per hundred, and p < 0.01, respectively). A history of working with e-waste was significantly associated with increased MNed BNC frequencies (odds ratio (OR), 38.85; 95% confidence interval (CI) = 1-1358.71, p = 0.044), independent of years of local residence, a perceived risk factor. However, there was no association between PBDEs exposure and oxidative DNA damage. Therefore, the exposure to PBDEs at the e-waste site may have an effect on the levels of TSH and genetoxic damage among these workers, but this needs to be validated in large studies.
Environmental Science and Technology 03/2008; 42(6):2195-200. · 5.23 Impact Factor
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ABSTRACT: Source tests were conducted to analyze and characterize diagnostic key tracers for emissions from burning of coals with various ranks. Ambient aerosol particulate matter was also collected in three areas of China and a background area in Corvallis, OR (U.S.) to confirm the presence of tracers specific for coal smoke. The results showed a series of aliphatic and aromatic hydrocarbons and phenolic compounds, including PAHs and hydroxy-PAHs as the major tracers, as well as a significant unresolved complex mixture (UCM) of compounds. The tracers that were found characteristic of coal combustion processes included hydroxy-PAHs and PAHs. Atmospheric ambient samples from Beijing and Taiyuan, cities where coal is burned in northern China, revealed that the hydroxy-PAH tracers were present during the wintertime, but not in cities where coal is not commonly used (e.g., Guangzhou, South China). Thus, the mass of hydroxy-PAHs can be apportioned to coal smoke and the source strength modeled by summing the proportional contents of EC (elemental carbon), PAHs, UCM and alkanes with the hydroxy-PAHs.
Environmental Science and Technology 12/2007; 41(21):7294-302. · 5.23 Impact Factor
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ABSTRACT: Polybrominated diphenyl ethers (PBDEs) are widely used as flame retardants. The aim of the present study was to evaluate the PBDE serum levels in residents from an electronic waste dismantling region, residents living within 50 km of the dismantling region, and a referent group with no occupational PBDE exposure. Fourteen PBDE congeners including BDE-28, BDE-47, BDE-99, BDE-100, BDE-153, BDE-154, BDE-183, BDE-196, BDE-197, BDE-203, BDE-206, BDE-207, BDE-208 and BDE-209 were quantified in these three groups by gas chromatography-negative chemical ionization (NCI) mass spectrometry in selected ion monitoring (SIM) mode. We found that the levels of all PBDE congeners in serum of residents from electronic waste dismantling region were significantly higher than those in the two other groups. The referents showed the lowest PBDE levels. Concentrations of congeners with a high number of bromine substituents, i.e., hepta- to decaBDEs in occupational exposure workers were 11-20 times higher than those in the referent group. BDE-209 was the dominant congener. The highest concentration of BDE-209 was observed among the electronic waste dismantling workers, and it was 3436 ng g(-1) lipid weight (ng g(-1) l.w.), which is the highest concentration of BDE-209 in humans worldwide. Some higher brominated PBDE congeners such as BDE-197, BDE-207 and BDE-208 also showed elevated concentrations in dismantling workers. This study confirms that BDE-209 is released to the environment and can bioaccumulate in the blood of electronic waste dismantling workers, and extensive occupational exposure to PBDEs leads to elevated concentrations of all PBDE congeners in serum.
Environment International 12/2007; 33(8):1029-34. · 5.30 Impact Factor
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ABSTRACT: In P.R. China, electronic waste (e-waste) from across the world is dismantled and discarded. Concentrations of polybrominated diphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs), and organochlorine pesticides (OCPs) were measured in serum from residents of an e-waste dismantling region (Guiyu, South China), where 80% of families work in e-waste recycling, and compared to a matching cohort from a nearby region where the fishing industry dominates (Haojiang). Serum concentrations of PBDEs and OCPs, but not PCBs, were significantly different in the two regions: the median sigmaPBDE concentration was 3 times higher in Guiyu than Haojiang, whereas the opposite was true for dichloro-diphenyl-trichloroethane (DDT). PBDEs typically accounted for 46% of the total organohalogen chemicals in samples from Guiyu, but 8.7% in Haojiang. The median BDE-209 concentration in Guiyu was 50-200 times higher than previously reported in occupationally exposed populations. The highest BDE-209 concentration was 3100 ng/g lipid, the highest yet reported in humans. Serum PBDE concentrations did not correlate with PCBs or OCPs, whereas PCBs and OCPs showed positive correlations, suggesting that sources of PBDEs to humans are different from PCBs and OCPs. The levels of PBDEs in individuals from Haojiang are possibly related to the recycling activity at Guiyu, through atmospheric transport.
Environmental Science and Technology 09/2007; 41(16):5647-53. · 5.23 Impact Factor
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ABSTRACT: We set out to determine whether infrared (IR) spectra of treated MCF-7 cells derived using attenuated total reflection Fourier-transform IR (ATR) microspectroscopy could be used to signature different exposures. Serum-lipid samples from residents living in an electronics waste (e-waste) dismantling region (Region E, n = 26) in the south of P.R. China or from a nearby region (Region S, n = 20) associated with the fishing industry were obtained. Following extraction, estrogen receptor-positive MCF-7 cells were treated for 24 h with < or = 5-mg lipid equivalent of individual extracts prior to ethanol fixation; subsequently, IR spectra of treated-cell populations were obtained using ATR microspectroscopy. Levels of organochlorinated and brominated compounds in parallel extracts were also determined. Principal component analysis (PCA) was employed to ascertain whether IR-spectral scores would cluster according to particular cohort. Scores plots following PCA highlighted significant clustering dependent on with which set of extracts MCF-7 cells were treated. This suggests marked differences in the cell-biochemical modulating effects induced by either set of extracts. Analysis of contaminant profiles in the extracts showed that polybrominated diphenyl ethers (PBDEs) accounted for 46.0% of total organohalogens and were higher than dichloro-diphenyl-trichloroethanes (DDTs) in Region E; DDTs were the major contaminants (85.2% of total contaminant load) compared to PBDEs (8.7%) in Region S. These results suggest that ATR microspectroscopy can segregate cell-biochemical effects as a consequence of very different exposure paradigms.
Environmental Science and Technology 08/2007; 41(16):5915-22. · 5.23 Impact Factor
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ABSTRACT: Size distribution aerosol samples were collected at an urban location of Guangzhou in four seasons of 2003-2004 by a MOUDI (Micro-orifice Uniform Deposit Impactor). The particle loading (PM10: 80-397 microg m(-3)) was comparable with some other Asia cities; however, much higher than that of Western Europe and North America. Polycyclic aromatic hydrocarbons (PAHs) were measured by gas chromatography with mass selective detector (GC-MS). Seasonal effects on the size distribution of PAHs are presented. Bimode (accumulation and coarse mode) and unimode (accumulation mode) distributions were observed for low-molecule-weight and high-molecule-weight PAHs. A slight shift to larger particles was found for the accumulation mode in autumn and winter, compared with that of spring and summer. One explanation is that the longer aging process of PAHs in autumn and winter would result in volatilization from finer particles followed by condensation onto coarser particles. Another is there was mixing process of local emission with long-range transported aerosol in autumn and winter. The relative higher value of IcdP/(BghiP+IcdP) and lower value of BghiP/BeP in winter also give evidences to the mixing process. The level of PAHs concentration has been much elevated in recent years. This can be attributed to the fast growth of motor vehicle and energy consumption.
Chemosphere 04/2007; 67(3):614-22. · 3.21 Impact Factor
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ABSTRACT: Polycyclic musks [cashmeran (DPMI), celestolide (ADBI), phantolide (AHMI), traseolide (ATII), tonalide (AHTN) and galaxolide (HHCB)] in the air, wastewater, sludge samples of a typical cosmetic plant were analyzed. DPMI, ADBI, HHCB and AHTN were found in all samples, and ATII was not found in any sample. HHCB and AHTN were the major components in all samples. The polycyclic musk concentrations were very high in the air of the cosmetic plant, and polycyclic musks were mostly contained in the gas phase at the percentage of 86.35-97.70%. Average polycyclic musk concentrations in effluent were high, and ranged from 0.62 to 32.06 microgl-1. The removal efficiency during the active sludge wastewater treatment was also high, resulting from the adsorption of those compounds into the sludge. So the polycyclic musk concentrations were very high in the primary sludge and second sludge, and ranged from 1.78 to 92.45 mgkg-1 (dry), and from 2.87 to 65.67 mgkg-1 (dry), respectively. Results suggested that the sludge needed to be further treated to make polycyclic musks less influence to the environment.
Chemosphere 02/2007; 66(2):252-8. · 3.21 Impact Factor
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ABSTRACT: Twenty-one-paired human fetal and maternal serum and 27 breast milk samples at South China were analyzed for concentrations of polybrominated diphenyl ethers (PBDEs). Seven PBDE congeners (BDE-28, -47, -99, -100, -153, -154, and -183) were quantified using gas chromatography/mass spectrometry (GC/MS). This is the first report to present the residue levels of PBDEs in human samples of China. The concentrations of total PBDEs ranged from 1.5 to 17 ng/g in the samples and were within the range reported in European samples for a similar population, but lower than human tissue levels in North America. BDE-47 and -153 were the dominant PBDE congeners in all samples and accounted for 60% of the total PBDEs. Further research is needed to determine the exposure route of PBDEs and their health effects.
Environmental Pollution 01/2007; 144(3):1024-30. · 3.75 Impact Factor
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ABSTRACT: Indoor and outdoor concentration levels of 21 carbonyl compounds and five BTEX (benzene, toluene, ethylbenzene and xylenes) were measured in four hospitals of Guangzhou from 2nd January to 20th March 2004. Samples were collected in five consecutive daytimes for each hospital. Among most of the samples, acetone was the most abundant carbonyl, followed by acetaldehyde, 2-butanone or formaldehyde. Toluene was the most abundant BTEX and the others were at similar levels. The relatively higher acetone concentrations might have resulted from the high level of background in Guangzhou area due to emission of the factories and LPG-fuel vehicles, and also for the special weather conditions during sampling time. The high concentration of acetaldehyde, which was even higher than that of formaldehyde, might be resulted from the wide use of ethanol in hospital. The partial oxidation of ethanol may form acetaldehyde. The indoor concentrations of carbonyls and BTEX were found a little higher than their outdoor counterparts with only a few exceptions, which showed the anthropogenic sources for these compounds. The low correlations between most carbonyls and BTEX concentrations might be caused by their complex sources. Finally, the human exposure levels of formaldehyde and acetaldehyde in hospitals are discussed.
Science of The Total Environment 10/2006; 368(2-3):574-84. · 3.29 Impact Factor
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ABSTRACT: Aerosol samples of PM10 and PM2.5 are collected in summertime at four monitoring sites in Guangzhou, China. The concentrations of organic and elemental carbons (OC/EC), inorganic ions, and elements in PM10 and PM2.5 are also quantified. Our study aims to: (1) characterize the particulate concentrations and associated chemical species in urban atmosphere (2) identify the potential sources and estimate their apportionment. The results show that average concentration of PM2.5 (97.54 microg m(-3)) in Guangzhou significantly exceeds the National Ambient Air Quality Standard (NAAQS) 24-h average of 65 microg m(-3). OC, EC, Sulfate, ammonium, K, V, Ni, Cu, Zn, Pb, As, Cd and Se are mainly in PM2.5 fraction of particles, while chloride, nitrate, Na, Mg, Al, Fe, Ca, Ti and Mn are mainly in PM2.5-10 fraction. The major components such as sulfate, OC and EC account for about 70-90% of the particulate mass. Enrichment factors (EF) for elements are calculated to indicate that elements of anthropogenic origins (Zn, Pb, As, Se, V, Ni, Cu and Cd) are highly enriched with respect to crustal composition (Al, Fe, Ca, Ti and Mn). Ambient and source data are used in the multi-variable linearly regression analysis for source identification and apportionment, indicating that major sources and their apportionments of ambient particulate aerosols in Guangzhou are vehicle exhaust by 38.4% and coal combustion by 26.0%, respectively.
Environmental Monitoring and Assessment 09/2006; 119(1-3):425-39. · 1.40 Impact Factor
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ABSTRACT: PM10 and PM2.5 samples were collected in the indoor environments of four hospitals and their adjacent outdoor environments in Guangzhou, China during the summertime. The concentrations of 18 target elements in particles were also quantified. The results showed that indoor PM2.5 levels with an average of 99 microg m(-3) were significantly higher than outdoor PM2.5 standard of 65 microg m(-3) recommended by USEPA [United States Environmental Protection Agency. Office of Air and Radiation, Office of Air Quality Planning and Standards, Fact Sheet. EPA's Revised Particulate Matter Standards, 17, July 1997] and PM2.5 constituted a large fraction of indoor respirable particles (PM10) by an average of 78% in four hospitals. High correlation between PM2.5 and PM10 (R(2) of 0.87 for indoors and 0.90 for outdoors) suggested that PM2.5 and PM10 came from similar particulate emission sources. The indoor particulate levels were correlated with the corresponding outdoors (R(2) of 0.78 for PM2.5 and 0.67 for PM10), demonstrating that outdoor infiltration could lead to direct transportation into indoors. In addition to outdoor infiltration, human activities and ventilation types could also influence indoor particulate levels in four hospitals. Total target elements accounted for 3.18-5.56% of PM2.5 and 4.38-9.20% of PM10 by mass, respectively. Na, Al, Ca, Fe, Mg, Mn and Ti were found in the coarse particles, while K, V, Cr, Ni, Cu, Zn, Cd, Sn, Pb, As and Se existed more in the fine particles. The average indoor concentrations of total elements were lower than those measured outdoors, suggesting that indoor elements originated mainly from outdoor emission sources. Enrichment factors (EF) for trace element were calculated to show that elements of anthropogenic origins (Zn, Pb, As, Se, V, Ni, Cu and Cd) were highly enriched with respect to crustal composition (Al, Fe, Ca, Ti and Mn). Factor analysis was used to identify possible pollution source-types, namely street dust, road traffic and combustion processes.
Science of The Total Environment 08/2006; 366(1):124-35. · 3.29 Impact Factor
