| 1. |
- Yu, Miao, et al.
(författare)
-
Metabolites of 2,4,4'-tribrominated diphenyl ether (BDE-28) in pumpkin after in vivo and in vitro exposure
- 2013
-
Ingår i: Environmental Science and Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 47:23, s. 13494-13501
-
Tidskriftsartikel (refereegranskat)abstract
- There is currently limited knowledge on PBDE metabolism in plants although they could play an important role in the environmental transformation of these persistent organic pollutants. In this study, pumpkin (Cucurbita maxima × C. moschata) was chosen as the model to understand the fate of BDE-28 in plants. MeO-tri-BDEs, OH-tri-BDEs, and OH-tri-BDEs were found as metabolites in plant samples of both in vivo hydroponic and in vitro tissue culture exposure. Three MeO-tri-BDEs were further identified as para-substituted metabolites. MeO-BDEs and OH-BDEs, respectively, accounted for about 1.6% and 1.5% (recovery corrected) of initial amount of BDE-28 according to the semiquantitative results. Other PBDEs, especially less brominated PBDEs as impurities in the standard of BDE-28, were also detected. The impurities and evaporation of the standard must be considered when trace metabolites are studied in exposure experiments.
|
|
| 2. |
- Liu, Runzeng, et al.
(författare)
-
Determination of nine benzotriazole UV stabilizers in environmental water samples by automated on-line solid phase extraction coupled with high-performance liquid chromatography-tandem mass spectrometry
- 2014
-
Ingår i: Talanta. - : Elsevier. - 0039-9140 .- 1873-3573. ; 120, s. 158-166
-
Tidskriftsartikel (refereegranskat)abstract
- A method using automated on-line solid phase extraction coupled with a high-performance liquid chromatography-tandem mass spectrometry system was developed for the determination of emerging benzotriazole UV stabilizers (BZTs) in different environmental water matrices including river water, sewage influent and effluent. Water sample was injected directly and the analytes were preconcentrated on a Polar Advantage II on-line SPE cartridge. After cleanup step the target BZTs were eluted in back flush mode and then separated on a liquid chromatography column. Experimental parameters such as sample loading flow rate, SPE cartridge, pH value and methanol ratio in the sample were optimized in detail. The method detection limits ranged from 0.21 to 2.17 ng/L. Recoveries of the target BZTs at 50 ng/L spiking level ranged from 76% to 114% and the inter-day RSDs ranged from 1% to 15%. The optimized method was successfully applied to analyze twelve water samples collected from different wastewater treatment plants and rivers, and five BZTs (UV-P, UV-329, UV-350, UV-234 and UV-328) were detected with concentrations up to 37.1 ng/L. The proposed method is simple, sensitive and suitable for simultaneous analysis and monitoring of BZTs in water samples.
|
|
| 3. |
- Liu, Runzeng, et al.
(författare)
-
Trace analysis of mono-, di-, tri-substituted polyfluoroalkyl phosphates and perfluorinated phosphonic acids in sewage sludge by high performance liquid chromatography tandem mass spectrometry
- 2013
-
Ingår i: Talanta. - : Elsevier. - 0039-9140 .- 1873-3573. ; 111, s. 170-177
-
Tidskriftsartikel (refereegranskat)abstract
- A new method using ultrasonic extraction and solid phase extraction (SPE) clean-up pretreatments was developed for the analysis of mono-, di- and tri-substituted polyfluoroalkyl phosphates (abbreviated as mono-PAPs, di-PAPs and tri-PAPs) and perfluorinated phosphonic acids (PFPAs) in sludge from wastewater treatment plants (WWTPs). For the ultrasonic extraction of three mono-PAPs, three di-PAPs and three PFPAs in sludge samples, a mixture of tetrahydrofuran/acetic acid (1:1, v/v) was found to be the most suitable extraction solvent. The subsequently optimized clean-up and enrichment procedures were carried out with weak anion exchange (WAX) cartridges in-line coupled with graphitized carbon black (ENVI-Carb) tubes. Two tri-PAPs were ultrasonically extracted by acetonitrile/tetrahydrofuran (1:1, v/v) and cleaned by mixed-mode anion exchange (MAX) in-line coupled with ENVI-Carb cartridges. The analytes were analyzed by optimized high performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) method either in negative or positive ionization mode. The method quantification limits (MQLs) of the 11 analytes in sludge ranged from 0.6 to 5.1 ng/g, meanwhile the total recoveries of the pretreatment varied from 24% (6:2 mono-PAP) to 107% (PFDPA). The method was successfully applied to analyze 16 sewage sludge samples collected from seven provinces in China, and two mono-PAPs were identified with concentrations ranging from
|
|
| 4. |
- Ruan, Ting, et al.
(författare)
-
Concentrations and composition profiles of benzotriazole UV stabilizers in municipal sewage sludge in China
- 2012
-
Ingår i: Environmental Science and Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 46:4, s. 2071-2079
-
Tidskriftsartikel (refereegranskat)abstract
- The environmental contamination and fate of benzotriazole UV stabilizers (BZTs) have received increasing attention due to their large production volume and wide usage in various consumer and industrial products. In the present work, 60 municipal sewage sludge samples from wastewater treatment plants (WWTPs) in 33 cities in China were collected to investigate the occurrence and distribution of 9 frequently used BZTs. The most dominant analogue was 2-[3,5-bis(1-methyl-1-phenylethyl)-2-hydroxyphenyl]benzotriazole (UV-234) at a median concentration of 116 ng/g (dry weight) and accounted on average for 27.2% of total BZTs. The abundance was successively followed by 2-(2-hydroxy-5-tert-octylphenyl)benzotriazole (UV-329, average 24.3%), 2-(2-hydroxy-3-tert-butyl-5-methylphenyl)-5-chlorobenzotriazole (UV-326, average 22.2%), 2-(3,5-di-tert-amyl-2-hydroxyphenyl)benzotriazole (UV-328, average 17.7%), and 2-(2-hydroxy-5-methylphenyl)benzotriazole (UV-P, average 6.6%), with median concentrations of 66.8, 67.8, 57.3, and 20.6 ng/g, respectively. 5-Chloro-2-(3,5-di-tert-butyl-2-hydroxyphenyl)benzotriazole (UV-327) and 2-(3-sec-butyl-5-tert-butyl-2-hydroxyphenyl)benzotriazole (UV-350) had low detection frequency, while 2-(3,5-di-tert-butyl-2-hydroxyphenyl)benzotriazole (UV-320) and 2-(5-tert-butyl-2-hydroxyphenyl)benzotriazole (UV-PS) were not detectable in any sample. To our knowledge, this is the first study reporting the occurrence of UV-234, UV-329, and UV-350 in sewage sludge in China. Significant correlations were found among the BZT concentrations and also with a WWTP characteristic (daily treatment volume). Furthermore, results from degradation prediction and multimedia fate simulation based on a quantitative structure-property relationship (QSPR) model at screening level also implied that the commercial BZT chemicals and their plausible transformation products might be persistent in the environment.
|
|
| 5. |
- Ruan, Ting, et al.
(författare)
-
Identification and composition of emerging quaternary ammonium compounds in municipal sewage sludge in China
- 2014
-
Ingår i: Environmental Science and Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 48:8, s. 4289-4297
-
Tidskriftsartikel (refereegranskat)abstract
- Quaternary ammonium compounds (QACs) have raised considerable attention due to their wide commercial applications and recent discovery of unknown persistent analogues in aqueous environment. In this work, the occurrence and distribution of alkyltrimethylammonium (ATMAC), benzylakyldimethylethylammonium (BAC) and dialkyldimethylammonium (DADMAC) homologues were investigated in fifty-two municipal sewage sludge samples. ATMAC C10-18, BAC C8-18 and paired DADMAC C8:8-C18:18 as well as emerging homologues such as ATMAC-20, 22 and mixed DADMAC-16:18 and 14:16 were present. Furthermore, paired DADMAC-20:20 and mixed DADMAC-14:18, 18:20 were identified for the first time by nontarget qualitative strategies. A triple quadruple mass spectrometer quantification method was also initially verified with the aid of laboratory synthesized standards for the analysis of the mixed DADMACs with no certificated commercial standards currently available. The total concentrations of ATMACs, BACs and DADMACs were in the range of 0.38-293, 0.09-191 and 0.64-344 μg/g dry weight, respectively, and particularly, mixed DADMACs constituted 39 ± 7% of total DADMAC concentrations. The concentrations and profiles of individual homologues further suggested different QAC applications and fate in China. Significant correlations were also found among the concentrations of various QAC homologues as well as wastewater treatment plant (WWTP) characteristics (total organic carbon contents and daily treatment volumes).
|
|
| 6. |
- Ruan, Ting, et al.
(författare)
-
Identification of novel polyfluorinated ether sulfonates as PFOS alternatives in municipal sewage sludge in China
- 2015
-
Ingår i: Environmental Science and Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 49:11, s. 6519-6527
-
Tidskriftsartikel (refereegranskat)abstract
- A 6:2 chlorinated polyfluorinated ether sulfonate (6:2 Cl-PFAES) with the trade name F-53B, is an alternative to perfluorooctanesulfonate (PFOS) in electroplating industry that is uniquely used in China. It was developed as a mist suppressant initially in the 1970s, but the environmental behaviors and potential adverse effects of the 6:2 Cl-PFAES have only recently been investigated. In this work, the occurrence and distribution of perfluoroalkyl sulfonate (PFSA), fluorotelomer sulfonate (FTSA), and PFAES analogues were investigated in municipal sewage sludge samples collected around China. Perfluorobutane, perfluorohexane, perfluorooctane, and perfluorodecanesulfonates, 6:2 and 8:2 FTSAs, and the emerging 6:2 Cl-PFAES were detected. Moreover, 8:2 and 10:2 Cl-PFAESs were identified for the first time as new polyfluorinated contaminants using high resolution mass spectrometry. These fluorinated analytes were further quantified with the aid of commercial and laboratory-purified standards. PFOS was the predominant contaminant with a geometric mean (GM) value of 3.19 ng/g dry weight (d.w.), which was subsequently followed by 6:2 Cl-PFAES and 8:2 Cl-PFAES (GM: 2.15 and 0.50 ng/g d.w., respectively). Both 6:2 and 8:2 Cl-PFAES were positively detected as the major components in the F-53B commercial product, and discrete 6:2 Cl-PFAES/8:2 Cl-PFAES ratios in the product and sludge samples might suggest 8:2 Cl-PFAES had enhanced sorption behavior in the sludge due to the increase in hydrophobicity.
|
|
| 7. |
- Song, Shanjun, et al.
(författare)
-
Distribution and preliminary exposure assessment of bisphenol AF (BPAF) in various environmental matrices around a manufacturing plant in China
- 2012
-
Ingår i: Environmental Science and Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 46:24, s. 13136-13143
-
Tidskriftsartikel (refereegranskat)abstract
- Increasing attention has been paid to bisphenol A and bisphenol (BP) analogues due to high production volumes, wide usage and potential adverse effects. Bisphenol AF (BPAF) is considered a new bisphenol analogue which is used as raw material in plastic industry, but little is known about its occurrence in the environment and the potential associated risk. In this work, BPAF levels and environmental distribution were reported in samples collected around a manufacturing plant and a preliminary exposure risk assessment to local residents was conducted. BPAF was detected in most of the samples, with levels in river ranging between
|
|
| 8. |
- Song, Shanjun, et al.
(författare)
-
Occurrence and profiles of bisphenol analogues in municipal sewage sludge in China
- 2014
-
Ingår i: Environmental Pollution. - : Elsevier. - 0269-7491 .- 1873-6424. ; 186, s. 14-19
-
Tidskriftsartikel (refereegranskat)abstract
- Extensive use of bisphenol A and its analogues has caused increasing concern over the potential adverse health impacts of these chemicals. In this study, the presence and profiles of 13 bisphenols (BPs) were investigated in 52 municipal sewage sludge samples collected from 30 cities in China. Tetrabromobisphenol A was the most frequently observed analogue (geometric mean: 20.5 ng/g dw). Bisphenol A (4.69 ng/g dw), bisphenol S (3.02 ng/g dw), and bisphenol F (3.84 ng/g dw) were found with similar frequency. Other BP analogues such as tetrachlorobisphenol A, bisphenol AF, bisphenol E, and dihydroxybiphenyl were identified for the first time in sewage sludge in China. Significant correlations were found among BP concentrations, but no relationships were found with wastewater treatment plant characteristics. Profiles of the relative estradiol equivalents suggested that the estrogenic potential of BP mixtures may be associated with the occurrence and contributions of specific analogues.
|
|
| 9. |
- Song, Shanjun, et al.
(författare)
-
Occurrence and removal of benzotriazole ultraviolet stabilizers in a wastewater treatment plant in China
- 2014
-
Ingår i: Environmental Science. - : Royal Society of Chemistry. - 2050-7887 .- 2050-7895. ; 16:5, s. 1076-1082
-
Tidskriftsartikel (refereegranskat)abstract
- Benzotriazole ultraviolet stabilizers (BZT-UVs) have previously been found in sludge from wastewater treatment plants (WWTPs), which might be potential sources of BZT-UVs to the surrounding environment. In this work, the occurrence and fate of seven emerging 2-hydroxyphenyl substituted BZT-UVs were investigated in a Chinese WWTP. This group of hydrophobic BZT-UVs possess log Kow values ranging from 4.31 to 7.67 which could be associated with their fate in WWTPs. Field samples including 24 h flow composites of influent, effluent and grab sludge samples from different treatment processes were collected and analyzed. Concentrations of BZT-UVs dissolved in aqueous-phases were in the range of 4.88±1.35 (UV-234) to 34.5±12.4 ng L-1 (UV-P) in the primary influent, while only UV-P and UV-328 were detected in the final effluent at concentrations of 10.5±6.59 and 2.74±1.73 ng L-1, respectively. Considering the amount of target BZT-UVs adsorbed to total suspended solids (TSS), the daily mass flux in the primary influent of the WWTP ranged from 22.3 g day(-1) (UV-P, 7.99%) to 74.0 g day-1 (UV-234, 26.5%). Total removal efficiency of the integrated treatment process ranged from 89.7% for UV-P to 99.7% for UV-234 suggesting nearly complete removal. Organic solid sedimentation in primary and secondary clarifiers was the dominant elimination route for BZT-UV analogues, which constituted 96.3% of the total removal efficiency. Advanced treatment (using ultraviolet disinfection) in this plant might further contribute to the high removal efficiencies (ranging from 19.6% to 77.3%).
|
|
