| 1. |
- Du, Xinyu, et al.
(författare)
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Tissue-Specific Accumulation, Sexual Difference, and Maternal Transfer of Chlorinated Paraffins in Black-Spotted Frogs
- 2019
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Ingår i: Environmental Science and Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 53:9, s. 4739-4746
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Tidskriftsartikel (refereegranskat)abstract
- The restriction on usage of short-chain chlorinated paraffins (SCCPs) under Stockholm Convention may promote the production and application of medium chain chlorinated paraffins (MCCPs) and long chain chlorinated paraffins (LCCPs) as substitutes. This study focused on the tissue-specific exposure to SCCPs, MCCPs, and LCCPs in black-spotted frog, a prevalent amphibian species in the Yangtze River Delta, China. The total CP concentrations in frog liver, muscle, and egg samples ranged of 35-1200, 6.3-97, and 6.8-300 ng/g wet weight (ww), respectively. Livers and eggs contained primary SCCPs (on average 78%) while MCCPs (43%) together with SCCPs (41%) were dominant in muscles. A significantly negative correlation was observed between hepatosomatic index and CPs concentration in liver (p < 0.01), indicating that CP exposure may lower survival rates of frogs by suppressing the energy storage in liver. Additionally, maternal transfer, an important uptake pathway for CPs, was evaluated for the first time by calculating the ratios of CP levels in eggs to those in their paired liver tissues. The ratio of egg to liver for CP congener groups raised with the increasing of log K-ow values, indicating mother to egg transport of CPs was related to the lipophilicity of the chemicals.
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| 2. |
- Niu, Dong, et al.
(författare)
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Novel brominated flame retardants in house dust from Shanghai, China : levels, temporal variation, and human exposure
- 2019
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Ingår i: Environmental Sciences Europe. - : Springer London. - 2190-4707 .- 2190-4715. ; 31:1
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Tidskriftsartikel (refereegranskat)abstract
- Background: Novel brominated flame retardants (NBFRs) have been increasingly used as alternatives to legacy BFRs (e.g., PBDEs and HBCDs) in consumer products, but are liable to emigrate and contaminate indoor dust. In this study, a total of 154 house dust samples including floor dust (FD) and elevated surface dust (ESD) were collected in the biggest metropolitan area (Shanghai) of East China in 2016. Limited information about temporal variation of NBFRs indoors is available, while the period of sampling is influential in human exposure estimates. Levels, temporal variation, and human exposure of seven target NBFRs such as decabromodiphenylethane (DBDPE), 1,2-bis(2,4,6-tribromophenoxy) ethane (BTBPE), 2-ethylhexyl 2,3,4,5-tetrabromobenzoate (EHTBB), and bis(2-ethylhexyl) tetrabromophthalate (BEHTEBP) were investigated in indoor house dust.Results: Concentrations of Sigma(7)NBFRs ranged from 19.11 to 3099ng/g with a geomean of 295.1ng/g in FD, and from 34.74 to 404.6ng/g with a geomean of 117.9ng/g in ESD. The geomeans of DBDPE were 219.6ng/g in FD and 76.89ng/g in ESD, accounting for 90.5% and 80.5% of Sigma(7)NBFRs. Levels of EHTBB, BTBPE, and DBDPE in FD exceeded significantly those in ESD. The temporal variation in Sigma(7)NBFRs in FD was ranked as summer>winter>autumn>spring. The daily exposure doses (DEDs) of Sigma(7)NBFRs via dust ingestion decreased as: infants>toddlers>children>teenagers>adults. Infants showed the highest DED in FD, 9.1ng/kg bw/day.Conclusions: DBDPE clearly dominated the NBFRs in both FD and ESD, but the concentrations of DBDPE in this study were generally moderate compared with the other international studies. Dust ingestion was the major pathway of human exposure to NBFRs indoors. About eightfold difference in exposure estimates between infants and adults showed that infants faced elevated exposure risks in FD. This study highlighted the necessity to estimate human exposure of NBFRs for different age groups using FD and ESD, respectively.
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| 3. |
- Zhou, Yihui, et al.
(författare)
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Shorter than short-chain : Very short-chain chlorinated paraffins (vSCCPs) found in wildlife from the Yangtze River Delta
- 2019
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Ingår i: Environment International. - : Elsevier BV. - 0160-4120 .- 1873-6750. ; 130
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Tidskriftsartikel (refereegranskat)abstract
- Very short-chain chlorinated paraffins (vSCCPs, C6-9) occurred in 94% of wildlife samples from the Yangtze River Delta (YRD), China, with CnClm comparable to that of a local CP product, CP-52. Therefore, we determined the content of vSCCPs in CP-52 using a mathematical deconvolution technique. Then with CP-52 and several other reference standards, vSCCPs together with short-, medium-, and long-chain CPs were quantified in 21 wildlife species from an artificial wetland ecosystem and a freshwater ecosystem in the YRD. Concentrations of vSCCPs ranged from 2.6 to 8400 ng/g lipid. These concentrations were 1.2-380 fold lower than SCCPs, but were significantly correlated with those of SCCPs. vSCCP concentrations were comparable to or higher than reported for brominated flame retardants in the same samples. Bioaccumulation tendency of vSCCPs was identified in two benthic species, indicating congener-specific accumulation of vSCCPs in the environment.
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