| 1. |
- Shang, Hongtao, et al.
(författare)
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Bioaccumulation of PCDD/Fs, PCBs and PBDEs by earthworms in field soils of an E-waste dismantling area in China
- 2013
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Ingår i: Environment International. - : Elsevier. - 0160-4120 .- 1873-6750. ; 54, s. 50-58
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Tidskriftsartikel (refereegranskat)abstract
- A total of 60 paired samples of earthworm, corresponding soil and wormcast were collected to investigate the bioaccumulation tendency of polychlorinated dibenzo-p-dioxins/dibenzofurans (PCDD/Fs), polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) in earthworms from a typical E-waste dismantling area in east China. Significant correlations were observed for the total concentrations among different matrix types except for PCDD/Fs in soil and earthworm. The bioaccumulation tendency showed some differences among the contaminants. Calculated biota-soil accumulation factors (BSAFs) indicated that PCBs and PBDEs had higher bioaccumulation potential compared to PCDD/Fs, which was somewhat different from laboratory studies. The plot of mean BSAFs versus log Kow values for PCBs and PBDEs was well fitted by a second-order polynomial with the maximum BSAF at approximately log Kow of 6.5. While for PCDD/Fs, only a slightly decreasing trend was observed with increasing log Kow. Composition analysis indicated that tetra-, penta- and hexa-halogenated homologs had higher bioaccumulation levels, indicating that medium-halogenated congeners with log Kow around 6.5 are more easily accumulated by earthworms. Furthermore, the ratios of BDE-47/-99 and BDE-99/-100 showed some discrepancies with the technical products and other biotic species, suggesting different bioaccumulation potential of PBDEs in earthworm.
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| 2. |
- Wang, Pu, et al.
(författare)
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Temporal trends of PCBs, PCDD/Fs and PBDEs in soils from an E-waste dismantling area in East China
- 2013
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Ingår i: Environmental Science. - : Royal Society of Chemistry. - 2050-7887 .- 2050-7895. ; 15:10, s. 1897-1903
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Tidskriftsartikel (refereegranskat)abstract
- The temporal trends of polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and polybrominated diphenyl ethers (PBDEs) were investigated in soils from an E-waste dismantling area in East China between 2005 and 2011. Isotope dilution high resolution gas chromatography/high resolution mass spectrometry (HRGC/HRMS) was employed for the sample analysis. PCB levels declined as expected, while PCDD/Fs generally remained at a constant level during the sampling period, and PBDE concentrations tended to be slightly lower after 2007 although the decline was not statistically significant. The congener profiles indicated that lowly-halogenated congeners of these persistent organic pollutants (POPs) accounted for the decreasing levels and relative proportions of the POPs, suggesting that they have been gradually eliminated from the field soil over the years. However, the concentration levels of some heavy congeners (e.g., CB-209, OCDD and OCDF) showed different trends from those of the lighter ones. The general tendencies of the three types of POPs in soils were consistent with those reported in other studies in this area. The results implied that the enhanced regulations and centralized dismantling action introduced in 2005 might exert a limited influence on these three types of POPs in soils during the sampling period.
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| 3. |
- Zhang, Haidong, et al.
(författare)
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Assessment on the occupational exposure of manufacturing workers to Dechlorane Plus through blood and hair analysis
- 2013
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Ingår i: Environmental Science and Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 47:18, s. 10567-10573
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Tidskriftsartikel (refereegranskat)abstract
- Dechlorane Plus (DP), as a widely used flame retardant in different electrical and textile applications, has recently attracted great concern around the world. The present study investigated the DP levels and distribution in human samples from a DP manufacturing plant and a nearby area in east China. The DP concentrations ranged from 89.8 to 2958 ng/g lipid weight in whole blood and 4.08 to 2159 ng/g dry weight in hair. For the workers engaged in DP manufacturing process, their DP levels were significantly higher than those in most of the other two control groups from the nearby area. The values of anti-DP fractional abundance (fanti ratio) were commonly lower in the human samples from both the manufacturing plant and nearby area compared with those in the commercial products, and excretion as well as biotransformation are possible reasons for stereoselective accumulation of the syn-DP isomer in humans. Furthermore, a significantly positive relationship (p < 0.05) was obtained between (i) the concentrations (and fanti) in the paired blood and hair samples, indicating a similar distribution pattern of the two DP isomers in the paired samples; (ii) the DP levels in human body and the exposure time (p < 0.05), which suggests that further assessment could be needed to investigate potential long-term risks to the occupational population.
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| 4. |
- Shang, Hongtao, et al.
(författare)
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The presence of polychlorinated biphenyls in yellow pigment products in China with emphasis on 3,3'-dichlorobiphenyl (PCB 11)
- 2014
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Ingår i: Chemosphere. - : Elsevier. - 0045-6535 .- 1879-1298. ; 98, s. 44-50
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Tidskriftsartikel (refereegranskat)abstract
- A non-Aroclor PCB congener, 3,3'-dichlorobiphenyl (PCB 11) has recently attracted wide concerns because of its environmental ubiquity and specific sources potentially associated with yellow pigment production. In order to investigate PCB 11 and other PCBs in the yellow pigment products, 24 yellow pigment samples were collected from three different manufacturing plants in China. ∑20PCBs and PCB 11 were in the range of 50.7-9.19×10(5) ng g−1 and 41.7-9.18×105 ng g−1, respectively, which was much higher than those reported in previous study. The corresponding TEQ values ranged between 0.16 and 4.21×103 ng WHO2005-TEQ kg−1. The contribution of PCB 11 to ∑20PCBs reached up to 85.5% (median value) followed by PCB 28, PCB 77, and PCB 52 with contributions of 10.5%, 6.70%, and 5.40%, respectively. Significant differences were observed for PCB 11 concentrations among the different types of yellow pigment from the same plant and among the same sample types from different plants. The PCB 11 concentrations in diarylide yellow pigments produced from 3,3'-dichlorbenzidine were the highest in all the samples. It demonstrates that yellow pigment is a significant source not only for the widespread pollution of PCB 11 but also for other PCBs, especially for the lower chlorinated congeners.
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| 5. |
- Wang, Haidong, et al.
(författare)
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Global, regional, and national levels of neonatal, infant, and under-5 mortality during 1990-2013 : a systematic analysis for the Global Burden of Disease Study 2013
- 2014
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Ingår i: The Lancet. - 0140-6736 .- 1474-547X. ; 384:9947, s. 957-979
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Remarkable financial and political efforts have been focused on the reduction of child mortality during the past few decades. Timely measurements of levels and trends in under-5 mortality are important to assess progress towards the Millennium Development Goal 4 (MDG 4) target of reduction of child mortality by two thirds from 1990 to 2015, and to identify models of success.METHODS: We generated updated estimates of child mortality in early neonatal (age 0-6 days), late neonatal (7-28 days), postneonatal (29-364 days), childhood (1-4 years), and under-5 (0-4 years) age groups for 188 countries from 1970 to 2013, with more than 29 000 survey, census, vital registration, and sample registration datapoints. We used Gaussian process regression with adjustments for bias and non-sampling error to synthesise the data for under-5 mortality for each country, and a separate model to estimate mortality for more detailed age groups. We used explanatory mixed effects regression models to assess the association between under-5 mortality and income per person, maternal education, HIV child death rates, secular shifts, and other factors. To quantify the contribution of these different factors and birth numbers to the change in numbers of deaths in under-5 age groups from 1990 to 2013, we used Shapley decomposition. We used estimated rates of change between 2000 and 2013 to construct under-5 mortality rate scenarios out to 2030.FINDINGS: We estimated that 6·3 million (95% UI 6·0-6·6) children under-5 died in 2013, a 64% reduction from 17·6 million (17·1-18·1) in 1970. In 2013, child mortality rates ranged from 152·5 per 1000 livebirths (130·6-177·4) in Guinea-Bissau to 2·3 (1·8-2·9) per 1000 in Singapore. The annualised rates of change from 1990 to 2013 ranged from -6·8% to 0·1%. 99 of 188 countries, including 43 of 48 countries in sub-Saharan Africa, had faster decreases in child mortality during 2000-13 than during 1990-2000. In 2013, neonatal deaths accounted for 41·6% of under-5 deaths compared with 37·4% in 1990. Compared with 1990, in 2013, rising numbers of births, especially in sub-Saharan Africa, led to 1·4 million more child deaths, and rising income per person and maternal education led to 0·9 million and 2·2 million fewer deaths, respectively. Changes in secular trends led to 4·2 million fewer deaths. Unexplained factors accounted for only -1% of the change in child deaths. In 30 developing countries, decreases since 2000 have been faster than predicted attributable to income, education, and secular shift alone.INTERPRETATION: Only 27 developing countries are expected to achieve MDG 4. Decreases since 2000 in under-5 mortality rates are accelerating in many developing countries, especially in sub-Saharan Africa. The Millennium Declaration and increased development assistance for health might have been a factor in faster decreases in some developing countries. Without further accelerated progress, many countries in west and central Africa will still have high levels of under-5 mortality in 2030.
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| 6. |
- Lin, Zhijing, et al.
(författare)
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Sick building syndrome, perceived odors, sensation of air dryness and indoor environment in Urumqi, China
- 2014
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Ingår i: Chinese Science Bulletin. - : Springer Science and Business Media LLC. - 1001-6538 .- 1861-9541. ; 59:35, s. 5153-5160
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Tidskriftsartikel (refereegranskat)abstract
- In order to evaluate the perceived home indoor air quality, as well as sick building syndrome (SBS) in areas with typical arid continental climate such as Urumqi, northwest of China, a cross-sectional study including 4,260 parents of children (1-8 years) was performed by a questionnaire survey in winter season in 2011. The sensation of air dryness (weekly/sometimes) in the last 3 months had the highest proportion of reports by more than half of the parents (57.4 %), followed by perceived stuffy odor (40.6 %), unpleasant odor (27.0 %), tobacco smoke odor (25.5 %), sensation of humid air (17.9 %), pungent odor (11.7 %) and moldy odor (9.5 %), respectively. The prevalence of SBS symptoms in the same time period was 40.4 % for general symptom, 47.7 % for mucosal symptom and 9.5 % for skin symptom, respectively. There were significant associations between perceived odors/sensation of air dryness and SBS symptoms (ORs range 1.39-1.42). Additionally, the OR values increased with an increase of the OH score (P < 0.05). Dampness, the presence of cockroaches and mosquitoes/flies, prenatal exposure to decoration and close to traffic were all risk factors of SBS symptoms. However, frequently putting bedding to sunshine was potentially a protective factor. In conclusion, adults' perceptions of odors and sensation of air dryness are related to SBS symptoms and home environmental factors in Urumqi, China.
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| 7. |
- Yang, Haidong, et al.
(författare)
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On source identification method for sudden water pollution accidents
- 2014
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Ingår i: Shui Kexue Jinzhan. - 1001-6791. ; 25:1, s. 122-129
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Tidskriftsartikel (refereegranskat)abstract
- In order to solve the source identification problem of sudden water pollution accident accurately and quickly, a method based on the Differential Evolution and Markov Chain Monte Carlo (MCMC) is presented. First, the problem is considered as a Bayesian estimation problem, and the posterior probability distribution of the unknown parameters that include source's position, intensity and events' initial time are deduced with Bayesian inference. Second, these unknown parameters are estimated by sampling the posterior probability distribution using the Differential Evolution algorithm and Markov Chain Monte Carlo simulation, and the sources are further identified. To test the effectiveness and accuracy of the proposed method, numerical experiments are carried out, and the model result is compared to that of the Bayesian-MCMC method. The conclusions are as following: three fourth of the iterations can be reduced, the average relative error of the source's position, intensity and events initial time are reduced 1.23%, 2.23% and 4.15%, their mean errors are decreased 0.39%, 0.83% and 1.49% by using the proposed method. The latter is thus more stable and robust than the Bayesian-MCMC method, and is able to identify the sudden water pollution accidents' source effectively. Therefore, this study provides a new approach and method to solve the difficult traceability problem of sudden water pollution accidents.
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