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Organochlorine pesticides accumulated by SPMD-based virtual organisms and feral fish in Three Gorges Reservoir, China
2015
Wang, Jingxian | Liang, Wei | Henkelmann, Bernhard | Pfister, Gerd | Schramm, Karl-Werner
Organochlorine pesticides (OCPs) accumulated by semipermeable membrane device (SPMD) -based virtual organisms (VOs) and local feral fish were studied in Three Gorges Reservoir (TGR), China. VOs were deployed at seven sites in TGR for two periods in 2009 and 5 species of fish with different living habitats and feeding habits collected in the same periods from two counties in TGR. 28 OCPs were analyzed and the concentration and profile of OCPs in fish were quite different from those in VOs. The lipid-based concentrations of OCPs in fish ranged from 225.7 ng/g lw to 1996.4 ng/g lw which were much higher than those in VOs which ranged from 17.3 to 112.4 ng/g lw. Dichlorodiphenyltrichloroethanes (DDTs) were the prevalent OCPs in the investigated fish, while hexachlorobenzene (HCB) was the dominant compound in VOs. DDT in the few fish sample analyzed was not of concern based on chemical contaminant limits of non-carcinogenic effect.
显示更多 [+] 显示较少 [-]Influences of ambient air PM2.5 concentration and meteorological condition on the indoor PM2.5 concentrations in a residential apartment in Beijing using a new approach
2015
Han, Yang | Qi, Meng | Chen, Yilin | Shen, Huizhong | Liu, Jing | Huang, Ye | Chen, Han | Liu, Wenxin | Wang, Xilong | Liu, Junfeng | Xing, Baoshan | Tao, Shu
PM2.5 concentrations in a typical residential apartment in Beijing and immediately outside of the building were measured simultaneously during heating and non-heating periods. The objective was to quantitatively explore the relationship between indoor and outdoor PM2.5 concentrations. A statistical method for predicting indoor PM2.5 concentrations was proposed. Ambient PM2.5 concentrations were strongly affected by meteorological conditions, especially wind directions. A bimodal distribution was identified during the heating season due to the frequent and rapid transition between severe pollution events and clean days. Indoor PM2.5 concentrations were significantly correlated with outdoor PM2.5 concentrations but with 1–2 h delay, and the differences can be explained by ambient meteorological features, such as temperature, humidity, and wind direction. These results indicate the potential to incorporate indoor exposure features to the regional air quality model framework and to more accurately estimate the epidemiological relationship between human mortality and air pollution exposure.
显示更多 [+] 显示较少 [-]Trends of deposition fluxes and loadings of sulfur dioxide and nitrogen oxides in the artificial Three Northern Regions Shelter Forest across northern China
2015
Zhang, Xiaodong | Huang, Tao | Zhang, Leiming | Gao, Hong | Shen, Yanjie | Ma, Jianmin
This study provides the first estimate of dry deposition fluxes of criteria air pollutants (SO2 and NOx) across the Three Northern Regions Shelter Forest (TNRSF) region in Northern China and their long-term trends from 1982 to 2010 using the inferential method. Dry deposition velocities of SO2 and NOx increased in many places of the TNRSF up to 118.2% for SO2 and 112.1% for NOx over the last three decades due to the increased vegetation coverage over the TNRSF. The highest atmospheric deposition fluxes of SO2 and NOx were found in the Central-North China region, followed by the Northeast and the Northwest China regions of the TNRSF. A total of 820,000 t SO2 and 218,000 t NOx was estimated to be removed from the atmosphere through dry deposition process over the TNRSF from 1982 to 2010. About 50% of the total removal occurred in the Central-North China region. The estimated total SO2 and NOx dry deposition fluxes from 1982 to 2010 between a TNRSF site in this region and an adjacent farmland outside the TNRSF showed that the fluxes of these two chemicals at the TNRSF site were the factors of 2–3 greater than their fluxes in the farmland.
显示更多 [+] 显示较少 [-]Concentration and chiral signature of chlordane in soils and sediments of the Central Tibetan Plateau, China: Transformation in the surficial process
2015
Yuan, Guo-Li | Wu, Ming-Zhe | Sun, Yong | Li, Jun | Han, Peng | Wang, Gen-Hou
The fraction of trans-chlordane (TC) in chlordane was used to indicate racemic degradation while the enantiomer fractions (EFs) indicated enantioselective depletion. In 44 soils of the Central Tibetan Plateau, the fractions of TC ranged from 0.368 to 0.411. The EFs ranged from 0.174 to 0.696 for TC and from 0.483 to 0.672 for cis-chlordane (CC). (−) enantiomer excess (ee) was found to be 80.0% in the soils for TC and (+) ee was 86.5% for CC. The fraction of TC changed with the clay content while the EFs changed with the soil organic carbon. Meanwhile, the fractions of TC and the EFs were determined for the surficial sediments in Yamzhog Yumco Lake, which were compared with those in the soils at its catchment area. The composition and chiral signature of chlordane did not vary between soils and sediments. Our results will help to elucidate the transformation of chlordane in soils and in surficial transport.
显示更多 [+] 显示较少 [-]Source contributions and regional transport of primary particulate matter in China
2015
Hu, Jianlin | Wu, Li | Zheng, Bo | Zhang, Qiang | He, Kebin | Chang, Qing | Li, Xinghua | Yang, Fumo | Ying, Qi | Zhang, Hongliang
A source-oriented CMAQ was applied to determine source sector/region contributions to primary particulate matter (PPM) in China. Four months were simulated with emissions grouped to eight regions and six sectors. Predicted elemental carbon (EC), primary organic carbon (POC), and PPM concentrations and source contributions agree with measurements and have significant spatiotemporal variations. Residential is a major contributor to spring/winter EC (50–80%), POC (60%–90%), and PPM (30–70%). For summer/fall, industrial contributes 30–50% for EC/POC and 40–60% for PPM. Transportation is more important for EC (20–30%) than POC/PPM (<5%). Open burning is important in summer/fall of Guangzhou and Chongqing. Dust contributes to 1/3–1/2 in spring/fall of Beijing, Xi'an and Chongqing. Based on sector–region combination, local residential/transportation and residential/industrial from Heibei are major contributors to spring PPM in Beijing. In summer/fall, local industrial is the largest. In winter, residential/industrial from local and Hebei account for >90% in Beijing.
显示更多 [+] 显示较少 [-]Ambient air pollution, temperature and out-of-hospital coronary deaths in Shanghai, China
2015
Dai, Jinping | Chen, Renjie | Meng, Xia | Yang, Changyuan | Zhao, Zhuohui | Kan, Haidong
Few studies have evaluated the effects of ambient air pollution and temperature in triggering out-of-hospital coronary deaths (OHCDs) in China. We evaluated the associations of air pollution and temperature with daily OHCDs in Shanghai, China from 2006 to 2011. We applied an over-dispersed generalized additive model and a distributed lag nonlinear model to analyze the effects of air pollution and temperature, respectively. A 10 μg/m3 increase in the present-day PM10, PM2.5, SO2, NO2 and CO were associated with increases in OHCD mortality of 0.49%, 0.68%, 0.88%, 1.60% and 0.08%, respectively. A 1 °C decrease below the minimum-mortality temperature corresponded to a 3.81% increase in OHCD mortality on lags days 0–21, and a 1 °C increase above minimum-mortality temperature corresponded to a 4.61% increase over lag days 0–3. No effects were found for in-hospital coronary deaths. This analysis suggests that air pollution, low temperature and high temperature may increase the risk of OHCDs.
显示更多 [+] 显示较少 [-]Spatiotemporal distribution of carbonyl compounds in China
2015
Ho, K.F. | Ho, Steven Sai Hang | Huang, R.-J. | Dai, W.T. | Cao, J.J. | Tian, Linwei | Deng, W.J.
A sampling campaign was carried out at nine Chinese cities in 2010/2011. Fifteen monocarbonyls (C# = 1–9) were quantified. Temperature is the rate-determining factor of the summertime carbonyl levels. The carbonyl emissions in winter are mainly driven by the primary anthropogenic sources like automobile. A molar ratio of propionaldehyde to nonaldehyde is a barometer of the impact of atmospheric vegetation emission which suggesting that strong vegetation emissions exist in summer and high propionaldehyde abundance is caused by fossil fuel combustion in winter. Potential health risk assessment of formaldehyde and acetaldehyde was conducted and the highest cumulative risks were observed at Chengdu in summer and Wuhan in winter. Because of the strong photochemical reaction and large amount of anthropogenic emissions, high concentrations of carbonyl compounds were observed in Chengdu. The use of ethanol-blended gasoline in Wuhan is the key reason of acetaldehyde emission and action should be taken to avoid potential health risks.
显示更多 [+] 显示较少 [-]Arsenate reduction and mobilization in the presence of indigenous aerobic bacteria obtained from high arsenic aquifers of the Hetao basin, Inner Mongolia
2015
Guo, Huaming | Liu, Zeyun | Ding, Susu | Hao, Chunbo | Xiu, Wei | Hou, Weiguo
Intact aquifer sediments were collected to obtain As-resistant bacteria from the Hetao basin. Two strains of aerobic As-resistant bacteria (Pseudomonas sp. M17-1 and Bacillus sp. M17-15) were isolated from the aquifer sediments. Those strains exhibited high resistances to both As(III) and As(V). Results showed that both strains had arr and ars genes, and led to reduction of dissolved As(V), goethite-adsorbed As(V), scorodite As(V) and sediment As(V), in the presence of organic carbon as the carbon source. After reduction of solid As(V), As release was observed from the solids to solutions. Strain M17-15 had a higher ability than strain M17-1 in reducing As(V) and promoting the release of As. These results suggested that the strains would mediate As(V) reduction to As(III), and thereafter release As(III), due to the higher mobility of As(III) in most aquifer systems. The processes would play an important role in genesis of high As groundwater.
显示更多 [+] 显示较少 [-]Microplastic in three urban estuaries, China
2015
Zhao, Shiye | Zhu, Lixin | Li, Daoji
Estuarine Microplastics (MPs) are limited to know globally. By filtering subsurface water through 330 μm nets, MPs in Jiaojiang, Oujiang Estuaries were quantified, as well as that in Minjiang Estuary responding to Typhoon Soulik. Polymer matrix was analyzed by Raman spectroscopy. MP (<5 mm) comprised more than 90% of total number plastics. The highest MPs density was found in Minjiang, following Jiaojiang and Oujiang. Fibers and granules were the primary shapes, with no pellets found. Colored MPs were the majority. The concentrations of suspended microplastics determine their bioavailability to low trophic organisms, and then possibly promoting the transfer of microplastic to higher trophic levels. Polypropylene and polyethylene were the prevalent types of MPs analyzed. Economic structures in urban estuaries influenced on MPs contamination levels. Typhoon didn't influence the suspended MP densities significantly. Our results provide basic information for better understanding suspended microplastics within urban estuaries and for managerial actions.
显示更多 [+] 显示较少 [-]Lead in Chinese villager house dust: Geographical variation and influencing factors
2015
Bi, Xiangyang | Liu, Jinling | Han, Zhixuan | Yang, Wenlin
House dust has been recognized as an important contributor to Pb exposure of children. Here we conducted a comprehensive study to investigate geographical variation of Pb in Chinese villager house dust. The influences of outdoor soil Pb concentrations, dates of construction, house decoration materials, heating types, and site specific pollution on Pb concentrations in house dust were evaluated. The concentrations of Pb in 477 house dust samples collected from twenty eight areas throughout China varied from 12 to 2510 mg/kg, with a median concentration of 42 mg/kg. The median Pb concentrations in different geographical areas ranged from 16 (Zhangjiakou, Hebei) to 195 mg/kg (Loudi, Hunan). No correlations were found between the house dust Pb concentrations and the age of houses, as well as house decoration materials. Whereas outdoor soil, coal combustion, and site specific pollution may be potential Pb sources. Principal component analysis (PCA) confirmed that elemental compositions of the house dust were controlled by both anthropogenic and geogenic sources. Using scanning electron microscopy (SEM), the Pb bearing particles in the house dust were also studied.
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