| 1. |
- Fu, Jianjie, et al.
(författare)
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Influence of e-waste dismantling and its regulations : temporal trend, spatial distribution of heavy metals in rice grains, and its potential health risk
- 2013
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Ingår i: Environmental Science and Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 47:13, s. 7437-7445
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Tidskriftsartikel (refereegranskat)abstract
- Enhanced regulations, centralized dismantling processes, and sophisticated recycling technologies have been implemented in some e-waste dismantling areas in China with regard to environmental and economic aspects since 2005. In this study, rice grain samples were collected from 2006 to 2010 in an e-waste dismantling area to investigate the temporal trends and spatial distribution of As, Cd, Cu, and Pb. Geometric means of As, Cd, Cu, and Pb in rice samples from the e-waste dismantling area were 111, 217, 4676, and 237 ng g(-1), respectively. Levels of Pb showed a significant decreasing trend during the sampling period, whereas the other three elements remained relatively constant or even increased. Concentrations of Cd, Cu, and Pb in the e-waste dismantling area were significantly higher than those in the non-e-waste dismantling area (p < 0.05), which showed a close connection between e-waste dismantling activities and elevated Pb, Cu, and Cd contents. Risk assessment for human via rice consumption indicated that over 60% of the hazard quotient of Cd exceeded 1 in the e-waste dismantling area. Our study implied that stricter implementation of regulatory measures might lead to positive effects in controlling the release of some heavy metals to the environment. However, environmental behaviors differed with geochemical characteristics of individual elements. Further remediation actions to reduce heavy metal pollution to the surrounding environment might still be needed.
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| 2. |
- Li, Zhuona, et al.
(författare)
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Effects of polycyclic musks HHCB and AHTN on steroidogenesis in H295R cells
- 2013
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Ingår i: Chemosphere. - : Elsevier. - 0045-6535 .- 1879-1298. ; 90:3, s. 1227-1235
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Tidskriftsartikel (refereegranskat)abstract
- 1,3,4,6,7,8-Hexahydro-4,6,6,7,8,8-hexamethylcyclopenta-(γ)-2-benzopyran (HHCB) and 7-acetyl-1,1,3,4,4,6-hexamethyl-1,2,3,4-tetrahydronaphthalene (AHTN) are widely used in personal care products. Previous studies showed that HHCB and AHTN can be found in various environmental matrices and have potential endocrine disrupting effects. However, the effects on adrenocortical function of HHCB and AHTN are not fully understood. This study evaluated the influences of HHCB and AHTN on seven steroid hormones (progesterone, aldosterone, cortisol, 17α-OH-progesterone, androstenedione, 17β-estradiol, and testosterone) and 10 genes involved in steroidogenic pathways (HMGR, StAR, CYP11A1, 3βHSD2, CYP17, CYP21, CYP11B1, CYP11B2, 17βHSD, and CYP19) using the H295R cell line in the absence and presence of 8-Br-cAMP. MC2R transcription on the cell membrane was also examined to further investigate the effects of HHCB and AHTN on adrenal steroidogenesis. The results demonstrated that HHCB and AHTN could inhibit progesterone and cortisol production mainly by the suppression of 3βHSD2 and CYP21. Meanwhile, high concentrations of AHTN can affect the sensitivity of H295R cells to ACTH by disrupting MC2R transcription. Overall, the results indicate that high concentrations of HHCB and AHTN can affect steroidogenesis in vitro using the H295R cell line.
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| 3. |
- Qu, Guangbo, et al.
(författare)
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Identification of tetrabromobisphenol A allyl ether and tetrabromobisphenol A 2,3-dibromopropyl ether in the ambient environment near a manufacturing site and in mollusks at a coastal region
- 2013
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Ingår i: Environmental Science and Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 47:9, s. 4760-4767
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Tidskriftsartikel (refereegranskat)abstract
- Tetrabromobisphenol A (TBBPA) is one of the most widely used brominated flame retardants (BFRs) and has been frequently detected in the environment and biota. Recent studies have found that derivatives of TBBPA, such as TBBPA bis(allyl) ether (TBBPA BAE) and TBBPA bis(2,3-dibromopropyl) ether (TBBPA BDBPE) are present in various environmental compartments. In this work, using liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) and liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (LC-Q-TOF-MS), TBBPA allyl ether (TBBPA AE) and TBBPA 2,3-dibromopropyl ether (TBBPA DBPE) were identified in environmental samples and further confirmed by synthesized standards. Soil, sediment, rice hull, and earthworm samples collected near a BFR manufacturing plant were found to contain these two compounds. In sediments, the concentrations of TBBPA AE and TBBPA DBPE ranged from 1.0 to 346.6 ng/g of dry weight (dw) and from 0.7 to 292.7 ng/g of dw, respectively. TBBPA AE and TBBPA DBPE in earthworm and rice hull samples were similar to soil samples, which ranged from below the method limit of detection (LOD, <0.002 ng/g of dw) to 0.064 ng/g of dw and from below the LOD (<0.008 ng/g of dw) to 0.58 ng/g of dw, respectively. Furthermore, mollusks collected from the Chinese Bohai Sea were used as a bioindicator to investigate the occurrence and distribution of these compounds in the coastal environment. The detection frequencies of TBBPA AE and TBBPA DBPE were 41 and 32%, respectively, and the concentrations ranged from below LOD (<0.003 ng/g of dw) to 0.54 ng/g of dw, with an average of 0.09 ng/g of dw, for TBBPA AE, and from below LOD (<0.008 ng/g of dw) to 1.41 ng/g of dw, with an average of 0.15 ng/g of dw, for TBBPA DBPE.
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