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Contamination status by persistent organic pollutants of the Atlantic spotted dolphin (Stenella frontalis) at the metapopulation level Full text
2018
Méndez-Fernandez, Paula | Taniguchi, Satie | Santos, Marcos C.O. | Cascão, Irma | Quérouil, Sophie | Martín, Vidal | Tejedor, Marisa | Carrillo, Manuel | Rinaldi, Carolina | Rinaldi, Renato | Montone, Rosalinda C.
The Atlantic spotted dolphin (Stenella frontalis) is an endemic species of the tropical-temperate Atlantic Ocean with widespread distribution. Although this species has been the subject of a large number of studies throughout its range, it remains in the “data deficient” category of the International Union for Conservation of Nature (IUCN). Chemical pollution by persistent organic pollutants (POPs) has been listed as one of the major threats to this species, however, there is no information on a wide scale. Thus, the aim of the present study was to investigate the contamination status of spotted dolphins on the metapopulation level as well as determine spatial and temporal variations in POP concentrations and bio-accumulation. A total of 115 blubber samples collected from a large part of the Atlantic basin were analysed for PCBs, DDTs, PBDEs, chlordanes, HCB and mirex. Although PCBs and DDTs were the predominant compounds in all areas, inter-location differences in POP concentrations were observed. Dolphins found at São Paulo, southeastern coast of Brazil, had the highest PCB concentrations (median: 10.5 μg/g lw) and Canary Islands dolphins had the highest DDT concentrations (median: 5.13 μg/g lw). Differences in PCB patterns among locations were also observed. Dolphins from the Azores and São Paulo demonstrated a similar pattern, with relatively highly contributions of tetra- (6.8 and 5.2%, respectively) and penta-CBs (25.6 and 23.8%, respectively) and lower contributions of hepta-CBs (20.8 and 23.5%, respectively) in comparison to other areas. Moreover, the sex of the animals and the year in which sampling or capture occurred exerted an important influence on the majority of the POPs analysed. Comparisons with toxicity thresholds available in the literature reveal that the São Paulo and Canary Island dolphins are the most vulnerable populations and should be considered in future conservation and management programs for the Atlantic spotted dolphin.
Show more [+] Less [-]VNN3, a potential novel biomarker for benzene toxicity, is involved in 1, 4-benzoquinone induced cell proliferation Full text
2018
Sun, Pengling | Guo, Xiaoli | Chen, Yujiao | Zhang, Wei | Duan, Huawei | Gao, Ai
Benzene is widely employed in the field of production, and its toxicity on biological systems has received increasing attention. Cell proliferation is a major life characteristic of living organisms. KLF15 and NOTCH1 are mature and classical genes in cell proliferation studies, particularly in the area of tumor investigation. The aim of this study was to investigate the effect and mechanism of VNN3 on cell proliferation induced by 1,4-benzoquinone (1,4-BQ), an important metabolite of benzene, and obtain a sensitive biomarker for the hazard screening and health care of benzene exposure. Normally growing AHH-1 cells were cultured in vitro and were incubated with different concentrations of 1,4-BQ (0, 10, 20, and 40 μM) for 24 h. A CCK-8 assay was used to assess the cell viability, whereas EdU was used to detect the cell proliferation of AHH-1 cells. The expression of VNN3, KLF15 and NOTCH1 was detected by real-time PCR. Moreover, a lentiviral model was constructed in AHH-1 cells to interfere with VNN3 expression. The results showed that 1,4-BQ clearly increased the expression of VNN3. Moreover, 1,4-BQ dose-dependently inhibited cell proliferation and caused increased KLF15 expression; in contrast, the NOTCH1 expression decreased in AHH-1 cells. Furthermore, following interference with the VNN3 expression, the cell proliferation inhibition and the expression of KLF15 and NOTCH1 were rescued. To further investigate the action of VNN3 in benzene hematotoxicity, we assessed it in benzene-exposed workers. The results showed that there was a remarkable correlation between the VNN3 expression and hemogram, which included RBC, NEUT and HGB. In addition, analysis of the KLF15 and NOTCH1 expression showed that the VNN3 expression was related to cell proliferation, which was consistent with the in vitro results. In conclusion, VNN3 influences cell proliferation induced by 1,4-BQ by regulating the expression of KLF15 and NOTCH1. VNN3 may represent a potential biomarker of benzene toxicity.
Show more [+] Less [-]Effects of prenatal exposure to air pollution on preeclampsia in Shenzhen, China Full text
2018
Wang, Qiong | Zhang, Huanhuan | Liang, Qianhong | Knibbs, Luke D. | Ren, Meng | Li, Changchang | Bao, Junzhe | Wang, Suhan | He, Yiling | Zhu, Lei | Wang, Xuemei | Zhao, Qingguo | Huang, Cunrui
The impact of ambient air pollution on pregnant women is a concern in China. However, little is known about the association between air pollution and preeclampsia and the potential modifying effects of meteorological conditions have not been assessed. This study aimed to assess the effects of prenatal exposure to air pollution on preeclampsia, and to explore whether temperature and humidity modify the effects. We performed a retrospective cohort study based on 1.21 million singleton births from the birth registration system in Shenzhen, China, between 2005 and 2012. Daily average measurements of particulate matter <10 μm (PM10), sulfur dioxide (SO2), nitrogen dioxide (NO2), air temperature (T), and dew point (Td) were collected. Logistic regression models were performed to estimate associations between air pollution and preeclampsia during the first and second trimesters, and during the entire pregnancy. In each time window, we observed a positive gradient of increasing preeclampsia risk with increasing quartiles of PM10 and SO2 exposure. When stratified by T and Td in three categories (<5th, 5th −95th, and >95th percentile), we found a significant interaction between PM10 and Td on preeclampsia; the adverse effects of PM10 increased with Td. During the entire pregnancy, there was a null association between PM10 and preeclampsia under Td < 5th percentile. Preeclampsia risk increased by 23% (95% CI: 19–26%) when 5th < Td < 95th percentile, and by 34% (16–55%) when Td > 95th percentile. We also found that air pollution effects on preeclampsia in autumn/winter seasons were stronger than those in the spring/summer. This is the first study to address modifying effects of meteorological factors on the association between air pollution and preeclampsia. Findings indicate that prenatal exposure to PM10 and SO2 increase preeclampsia risk in Shenzhen, China, and the effects could be modified by humidity. Pregnant women should limit air pollution exposure, particularly during humid periods.
Show more [+] Less [-]Changes of total and freely dissolved polycyclic aromatic hydrocarbons and toxicity of biochars treated with various aging processes Full text
2018
Oleszczuk, Patryk | Kołtowski, Michał
The aim of this study was to determine the effect of biochar aging on the content of polycyclic aromatic hydrocarbons (PAHs) (the total content – Ctot, and the freely dissolved – Cfree) in biochar and its ecotoxicity. Two biochars (BCS and BCM) with varying properties were aged for 420 days at different temperatures (−20 °C, 4 °C, 20 °C, 70 °C), at a variable temperature (−20/20 °C), in the presence of nutrients, and in the presence of inoculum and nutrients. After the aging process, Ctot and Cfree PAHs were determined in samples obtained and an ecotoxicological analysis was performed, which involved tests with bacteria (Vibrio fischeri), invertebrates (Folsomia candida) and plants (Lepidium sativum). Aging significantly affected all the parameters tested. The range of changes in the studied parameters depended on the type of biochar and ageing conditions. In the case of most of the aging methods, PAH content (Ctot, Cfree) and toxicity were found to decrease. Aging in the presence of microorganisms and nutrients and in the presence of nutrients alone caused the greatest reduction in Ctot PAH content (a reduction from 30 to 100% relative to non-aged biochar), Cfree PAH content (a reduction from 12 to 100%), root growth inhibition (a reduction from 73 to 90%), and luminescence inhibition (a reduction from 24 to 100%). In the case of Cfree PAHs and toxicity to F. candida, some aging methods caused their increase. The study also found a significant relationship between the changes in Ctot PAH content during aging and inhibition of root growth (BCS, BCM) and inhibition of V. fischerii luminescence (BCM). In no case was a significant correlation (P ≥ 0.05) between Cfree PAHs and the investigated toxicity parameters found.
Show more [+] Less [-]Insights about sources, distribution, and degradation of sewage and biogenic molecular markers in surficial sediments and suspended particulate matter from a human-impacted subtropical estuary Full text
2018
Cabral, Ana Caroline | Martins, César C.
The molecular markers sterols and linear alkylbenzenes (LABs) were analyzed in the surficial sediments and suspended particulate matter (SPM) of a subtropical estuary in South Atlantic (Paranaguá Estuarine System). The purpose of this study was identify the spatial distribution of sewage and the input of biogenic organic matter (OM) and to provide comparative insights about their behavior, compositions, and sources. The concentration of coprostanol ranged from < DL (detection limit) to 2.67 μg g−1 in SPM and from < DL to 0.94 μg g−1 in sediments. Total LABs ranged from 43.8 to 480.0 ng g−1 in SPM and from < DL to 21.0 ng g−1 in sediments. LABs homologs composition varied between the two matrices. The local hydrodynamic pattern may promote water column homogenization, dispersion, and dilution of sewage particles, and preferential sedimentation in fluvial and mixture zones. Results suggest that SPM is a good matrix for larger spatial and short time scale evaluation while sediments may help to define hot spot areas of input and final deposition of sewage particles. Marine sterols predominated in SPM while no dominance patterns of marine/terrestrial sterols occurred in surficial sediments. The higher degradation rates of sterols and LABs in the water column must be the main factor for the sharp drop in concentration towards the sediment and the variation of the preferential composition of these markers between compartments.
Show more [+] Less [-]Nano-rod Ca-decorated sludge derived carbon for removal of phosphorus Full text
2018
Kong, Lingjun | Han, Meina | Shih, Kaimin | Su, Minhua | Diao, Zenghui | Long, Jianyou | Chen, Diyun | Hou, Li'an | Peng, Yan
Recovering phosphorus (P) from waste streams takes the unique advantage in simultaneously addressing the crisis of eutrophication and the shortage of P resource. A novel calcium decorated sludge carbon (Ca-SC) was developed from dyeing industry wastewater treatment sludge by decorating calcium (Ca) to effectively adsorb phosphorus from solution. The X-ray diffraction (XRD) and Fourier transform infrared (FTIR) techniques were used to characterize the Ca-SCs, followed by isotherm and kinetic sorption experiments. A preferred design with CaCO₃ to sludge mass ratio of 1:2 was found to have a sorption capacity of 116.82 mg/g for phosphorus. This work reveals the crucial role of well-dispersed nano-rod calcium on the Ca-SC surface for the sorption of phosphorus. Moreover, the decoration of nano-rod calcium was found to further promote the uptake of phosphorus through the formation of hydroxylapatite (Ca₅(PO₄)₃(OH)). Thus, the development of decorated Ca-SC for sorption of phosphorus is very important in solving the P pollution and resource loss.
Show more [+] Less [-]How do people in different places experience different levels of air pollution? Using worldwide Chinese as a lens Full text
2018
Chen, Bin | Song, Yimeng | Kwan, Mei-po | Huang, Bo | Xu, Bing
Air pollution, being especially severe in the fast-growing developing world, continues to post a threat to public health. Yet, few studies are capable of quantifying well how different groups of people in different places experience different levels of air pollution at the global scale. In this paper, we use worldwide Chinese as a lens to quantify the spatiotemporal variations and geographic differences in PM2.5 exposures using unprecedented mobile phone big data and air pollution records. The results show that Chinese in South and East Asia suffer relatively serious PM2.5 exposures, where the Chinese in China have the highest PM2.5 exposures (52.8 μg/m3/year), which is fourfold higher than the exposures in the United States (10.7 μg/m3/year). Overall, the Chinese in Asian cities (35.5 μg/m3/year) experienced the most serious PM2.5 exposures when compared with the Chinese in the cities of other continents. These results, partly presented as a spatiotemporally explicit map of PM2.5 exposures for worldwide Chinese, help researchers and governments to consider how to address the effects of air pollution on public health with respect to different population groups and geographic locations.
Show more [+] Less [-]Protein and lipid growth rates regulate bioaccumulation of PCBs and Hg in Bighead Carp (Hypophthalmichthys nobilis) and Silver Carp (Hypophthalmichthys molitrix) from the Three Gorges Reservoir, China Full text
2018
Li, Jiajia | Haffner, G Douglas | Wang, Dingyong | Zhang, Lei | Li, Yun | Deng, Huatang | Drouillard, Kenneth G.
This study evaluated the effect of growth of different tissue compartments on the bioaccumulation of mercury (Hg) and polychlorinated biphenyls (PCBs) in Silver Carp (Hypophthalmichthys molitrix) and Bighead Carp (Hypophthalmichthys nobilis) from the Three Gorges Reservoir (TGR), China. A non-steady state bioenergetics/toxicokinetic model was developed to simulate PCB and Hg concentrations in these two species and compared with field data. Simulations using constant whole body growth rate and constant tissue to whole body weight ratios were contrasted against simulations adopting age specific whole body and tissue/age specific growth rates for their goodness of fit to field data. The simulations using age/tissue specific growth rates demonstrated better fit to field data for PCBs compared to the constant growth rate models (22% improved R²), while both models explained similar variation in Hg concentration data. Both species demonstrated higher growth rates of lipids (on a daily basis) relative to whole body and protein contributing to higher growth dilution of PCBs compared to Hg. Although stable isotope data indicated some degree of diet and/or habitat shift, simulations assuming a constant diet concentration explained between 36 and 40% of the variation in fish concentrations for both contaminants and fish species. This study demonstrates that differences in the bioaccumulation rate of PCBs and Hg by Asian carp can be partially explained by differences in the growth rates of key tissue storage compartments associated with each contaminant. These differences in chemical-specific growth dilution subsequently contribute to differences in chemical retention and bioaccumulation patterns of Hg and PCBs by fish.
Show more [+] Less [-]Acute sensitivity of three Cladoceran species to different types of microplastics in combination with thermal stress Full text
2018
Jaikumar, Gayathri | Baas, Jan | Brun, Nadja R. | Vijver, Martina G. | Bosker, Thijs
Microplastics (<5 mm, MP) are ubiquitously distributed in the environment, causing increasing concern regarding their potential toxicity to organisms. To date, most research has focussed on the impacts of MPs on marine and estuarine organisms, with fewer studies focussing on the effects of microplastics on freshwater ecosystems, especially under different environmental conditions. In the present study, the sensitivity of two temperate Cladoceran species, Daphnia magna and Daphnia pulex, and a smaller tropical species Ceriodaphnia dubia, to primary microplastics (PMP) and secondary (weathered) microplastics (SMP) was assessed. A prolonged acute toxicity assay (up to 72 or 96 h) was performed at 18°, 22°, and 26 °C, to determine the influence of temperature as an additional stressor and survival data were analysed using toxicokinetic-toxicodynamic (TK-TD) model. Acute sensitivity of D. magna and D. pulex to both PMP and SMP increased sharply with temperature, whereas that of C. dubia remained relatively stable across temperatures. C. dubia was the most sensitive species at 18 °C, followed by D. pulex and D. magna, which were of comparable sensitivity. However, this ranking was reversed at 26 °C as could be seen from the No Effect Concentration (NEC) estimates of the TK-TD model. In addition, SMP and PMP had a similar effect on D. magna and D. pulex, but PMP was more toxic to C. dubia. Effects on survival were strongly time-dependent and became substantially more severe after the standard 48 h test period. Our results indicate that sensitivity to microplastics may differ between species for different types of microplastics, and could be drastically influenced by temperature albeit at high exposure concentrations.
Show more [+] Less [-]Retraction notice to “Signalling cross-talk between nitric oxide and active oxygen in Trifolium repens L. plants responses to cadmium stress” [Environ. Pollut. 239 (2018) 53–68] Full text
2018
Liu, Shiliang | Yang, Rongjie | Tripathi, Durgesh Kumar | Li, Xi | Jiang, Mingyan | Lv, Bingyang | Ma, Mingdong | Chen, Qibing
This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal).This article has been retracted at the request of the Editors-in-Chief.The authors have plagiarized part of a paper that had appeared in Plant, Cell & Environment, 29 (2006) 1532–1544. https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1365-3040.2006.01531.x The images that were reused were: Fig. 1e, 1f, 1g, 1h, 2a, 2b, 2e, 2f.One of the conditions of submission of a paper for publication is that authors declare explicitly that their work is original and has not appeared in a publication elsewhere. Re-use of any data should be appropriately cited. As such this article represents a severe abuse of the scientific publishing system. The scientific community takes a very strong view on this matter and apologies are offered to readers of the journal that this was not detected during the submission process.
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