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Bi L.-M.,Kunming University of Science and Technology | Hao J.-M.,Kunming University of Science and Technology | Hao J.-M.,Tsinghua University | Ning P.,Kunming University of Science and Technology | And 3 more authors.
Zhongguo Huanjing Kexue/China Environmental Science | Year: 2015

A set of PM2.5 samples from three sampling sites belonging to the regional air monitoring networks of Kunming were collected during April 2013 to January 2014, and 16selected PAHs were analyzed by GC-MS. Average concentrations of PM2.5-bound PAHs from the industrial area (Jinding Mountain), traffic area (Dongfeng Tung Road) and clean area (Xishan Forest Park) were 40.67, 22.64, 22.07 ng/m3. High atmospheric pressure and the input of air mass originated from the Qujing area were the cause of rising PAHs concentration in Kunming. Result of health risk assessment of PAHs showed, the concentration of BaPeq at Jinding Mountain, Dongfeng Tung Road and Xishan Forest Park was 6.28, 4.00, 2.94 ng/m3, respectively, exceeded the national ambient air quality standard (2.5 ng/m3) in China. The PAHs in industrial area and traffic area were mainly influenced by vehicle emission (50.80% and 40.20%), followed by coal combustion (35.55% and 39.23%), biomass combustion (7.30% and 7.98%); clean area was effected by vehicle emission (81.84%) and biomass combustion (9.73%). ©, 2015, Chinese Society for Environmental Sciences. All right reserved. Source

Wang B.,Kunming University of Science and Technology | Wan X.,Kunming University of Science and Technology | Zhao S.,Kunming University of Science and Technology | Zhao S.,Kunming Environmental Monitoring Center | And 3 more authors.
Chromatographia | Year: 2011

An efficient and reliable method based on gas chromatography-mass spectrometry (GC-MS) was developed for the extraction and analysis of six phenolic endocrine disrupting chemicals (EDCs), such as 4-nonylphenol (4-NP), nonylphenol-mono-ethoxylate (NP1EO), nonylphenol-di-ethoxylate (NP2EO), 4-tert-octylphenol (4-t-OP), bisphenol A (BPA) and 4-cumylphenol (4-CP) in surface water and sediment. The method was developed by using microwave-assisted extraction (MAE), solid phase extraction (SPE) and derivatization procedure. The MAE procedures were performed by optimizing three key process factors, consisted of extraction solvent, extraction temperature and holding time, affecting the extraction efficiency from sediment samples. For SPE, various parameters that may affect the recovery efficiency of water samples, such as SPE phase cartridge, elution solvent, as well as pH of water samples, were investigated. A series of derivatization conditions, such as derivatization reagent, reaction temperature and reaction time, were improved. The method achieved good repeatability and reproducibility with relative standard deviations <13% for all target EDCs in the both samples. Satisfactory recoveries for spiked water and sediment samples ranged from 85 to 101% and 74 to 105%, respectively. The limits of quantification varied from 0.20 (4-t-OP) to 11.50 ng L-1 (NP2EO) and from 0.31 (4-t-OP) to 9.50 ng g -1 dry weight (dw) (NP2EO) for water samples and sediment samples, respectively. The established method was successfully applied to the analysis of target EDCs in surface water and sediment samples collected from Caohai site of Dianchi Lake, China. The results showed that NP1EO, NP2EO and BPA were the three dominant phenolic EDCs in the site, reaching 114, 97 and 149 ng L -1 in surface water, while 444, 186 and 178 ng g-1 dw in surface sediment, respectively. © 2011 Springer-Verlag. Source

Yang C.,Yunnan University | Chen G.,Yunnan University | Li S.,Yunnan University | Feng W.,Kunming Environmental Monitoring Center | And 5 more authors.
Chinese Journal of Environmental Engineering | Year: 2016

Based on the investigation of the contents and distribution of acid volatile sulfide (AVS) and synchronous extracted metals (SEM) in surface sediments of Yangzonghai Lake. We assessed the bioavailability of heavy metals in the surface sediments of the lake by using SEM/AVS model. In the meantime, TEL and PEL methods were employed to assess the bioavailability of each single metal. The results showed that: AVS in the surface sediments of the lake ranges from 15.09 to 149.74 μmol/g, with the mean of 49.42 μmol/g, which decreaseds gradually from south to north and shows positive correlation with depth of water in the south and north of the lake respectively. ∑SEM(include: Cu, Cr, Pb, Zn, Mn, As, Cd) ranges from 4.84 to 16.10 μmol/g, with the mean of 10.28 μmol/g, which has greater value in the north than that in the south, with a small fluctuation. SEM/AVS<1 is found at each sample site, implying that there is no bioavailability of heavy metals in the sediment of the lake. In terms of single metal, Pb is more possible and Cu is possible to produce the biological toxicity, the others are next to impossible to produce the biological toxicity. © 2016, Science Press. All right reserved. Source

Zhao S.M.,Kunming University of Science and Technology | Zhao S.M.,Kunming Environmental Monitoring Center | Wang B.,Southwest University of Science and Technology | Wang D.W.,Kunming University of Science and Technology | And 5 more authors.
International Journal of Environmental Research | Year: 2014

Polycyclic aromatic hydrocarbons (PAHs) in the priority controlling list of US EPA were systematically evaluated in surface sediments in Dianchi Lake and its estuaries. Total PAH concentrations (σPAHs) varied from 210 to 11,070 ng/g dry weight (d.w.) in Dianchi Lake, and from 230 to 12,271 ng/g d.w. in the estuaries. σPAHs in sediments from Caohai section were higher than those from Waihai section. The occurrences of PAHs in the Lake were closely related to the distributions of rivers, indicating that the river runoff was an important pathway of PAHs into the Lake. Compared with the US Sediment Quality Guidelines (SQGs), σPAHs in most area were below the effect range low (ERL), which implied that the adverse biological effects would occur rarely. The toxic equivalent concentrations of potentially carcinogenic PAHs (TEQcarc) varied from 19 to 967 ng TEQ/g d.w., and the higher values were found in northern Caohai area. The proportions of the toxic equivalent quantity (TEQcarc) to the total TEQs in sediments were all above 96%, suggesting that the carcinogenicity of PAHs could be occurred. Significantly positive correlations between total organic carbon (TOC) and less molecular weight PAHs (2, 3-ring) (LPAHs) were observed in the Lake. Diagnostic ratios showed that the primary source of PAHs in Dianchi Lake and most estuaries is biomass combustion, but is petroleum combustion or petrogenic origin in several other estuaries. Source

Wan X.,Kunming University of Science and Technology | Pan X.,Kunming University of Science and Technology | Wang B.,Kunming University of Science and Technology | Zhao S.,Kunming University of Science and Technology | And 5 more authors.
Chemosphere | Year: 2011

Six commonly occurring polychlorinated biphenyl congeners (PCB28, PCB52, PCB101, PCB138, PCB153 and PCB180) were measured in water, surface sediments, and sediment core samples from 10 monitoring stations across Dianchi Lake in Kunming, China to determine the distributions, historical trends, and sources of PCBs to this ecologically and regionally important water body. The summed total concentration of all six PCB congeners ranged from 13 to 72ngL -1 in water, 0.6-2.4ngg -1dry weight (d.w.) in surface sediment, and from non-detectable to 2.2ngg -1d.w. in sediment core samples. The six PCB congeners were found to demonstrate similar distribution characteristics across water and surface sediment samples, with PCB28 and PCB52 accounting for more than 67% of the total summed concentration in both matrices. The concentration of individual congeners in each media decreased in the order of PCB28>PCB52>PCB101≈PCB138≈PCB153≈PCB180. Analysis of PCB congeners in sediment core layers as a function of depth revealed two distinct peaks occurring in the top velocity layer and in the layer between 25 and 30cm in depth (corresponding to 1970s). Core sediment analysis showed PCBs are currently being released to Dianchi Lake and showed the historical trends of PCB deposition into the lake sediment. Data from this multi-media exploration of PCBs can be used by researchers, regulators, and policy makers to understand the fate of PCBs in Dianchi Lake, and also to begin to identify current sources of PCBs to the lake. © 2011 Elsevier Ltd. Source

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