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Exposure of juvenile turbot (Scophthalmus maximus) to silver nanoparticles and 17α-ethinylestradiol mixtures: Implications for contaminant uptake and plasma steroid hormone levels Полный текст
2017
Farkas, Júlia | Salaberria, Iurgi | Styrishave, Bjarne | Staňková, Radka | Ciesielski, Tomasz M. | Olsen, Anders J. | Posch, Wilfried | Flaten, Trond P. | Krøkje, Åse | Salvenmoser, Willi | Jenssen, Bjørn M.
Exposure of juvenile turbot (Scophthalmus maximus) to silver nanoparticles and 17α-ethinylestradiol mixtures: Implications for contaminant uptake and plasma steroid hormone levels Полный текст
2017
Farkas, Júlia | Salaberria, Iurgi | Styrishave, Bjarne | Staňková, Radka | Ciesielski, Tomasz M. | Olsen, Anders J. | Posch, Wilfried | Flaten, Trond P. | Krøkje, Åse | Salvenmoser, Willi | Jenssen, Bjørn M.
Combined exposure to engineered nanoparticles (ENPs) and anthropogenic contaminants can lead to changes in bioavailability, uptake and thus effects of both groups of contaminants. In this study we investigated effects of single and combined exposures of silver (Ag) nanoparticles (AgNPs) and the synthetic hormone 17α-ethinylestradiol (EE2) on tissue uptake of both contaminants in juvenile turbot (Scophthalmus maximus). Silver uptake and tissue distribution (gills, liver, kidney, stomach, muscle and bile) were analyzed following a 14-day, 2-h daily pulsed exposure to AgNPs (2 μg L⁻¹ and 200 μg L⁻¹), Ag⁺ (50 μg L⁻¹), EE2 (50 ng L⁻¹) and AgNP + EE2 (2 or 200 μg L⁻¹+50 ng L⁻¹). Effects of the exposures on plasma vitellogenin (Vtg) levels, EE2 and steroid hormone concentrations were investigated. The AgNP and AgNP + EE2 exposures resulted in similar Ag concentrations in the tissues, indicating that combined exposure did not influence Ag uptake in tissues. The highest Ag concentrations were found in gills. For the Ag⁺ exposed fish, the highest Ag concentrations were measured in the liver. Our results show dissolution processes of AgNPs in seawater, indicating that the tissue concentrations of Ag may partly originate from ionic release. Plasma EE2 concentrations and Vtg induction were similar in fish exposed to the single contaminants and the mixed contaminants, indicating that the presence of AgNPs did not significantly alter EE2 uptake. Similarly, concentrations of most steroid hormones were not significantly altered due to exposures to the combined contaminants versus the single compound exposures. However, high concentrations of AgNPs in combination with EE2 caused a drop of estrone (E1) (female fish) and androstenedione (AN) (male and female fish) levels in plasma below quantification limits. Our results indicate that the interactive effects between AgNPs and EE2 are limited, with only high concentrations of AgNPs triggering synergistic effects on plasma steroid hormone concentrations in juvenile turbots.
Показать больше [+] Меньше [-]Exposure of juvenile turbot (Scophthalmus maximus) to AgNP-EE2 mixtures: Implications on contaminant bioavailability and plasma steroid hormone levels Полный текст
2017
Farkas, Julia | Salaberria, Iurgi | Styrishave, Bjarne | Stanková, Radka | Ciesielski, Tomasz Maciej | Olsen, Anders Johny | Posch, Wilfried | Flaten, Trond Peder | Krøkje, Åse | Salvenmoser, Willi | Jenssen, Bjørn Munro
Combined exposure to engineered nanoparticles (ENPs) and anthropogenic contaminants can lead to changes in bioavailability, uptake and thus effects of both groups of contaminants. In this study we investigated effects of single and combined exposures of silver (Ag) nanoparticles (AgNPs) and the synthetic hormone 17a-ethinylestradiol (EE2) on tissue uptake of both contaminants in juvenile turbot (Scophthalmus maximus). Silver uptake and tissue distribution (gills, liver, kidney, stomach, muscle and bile) were analyzed following a 14-day, 2-h daily pulsed exposure to AgNPs (2 mg L 1 and 200 mg L 1), Agþ (50 mg L 1), EE2 (50 ng L 1) and AgNP þ EE2 (2 or 200 mg L 1þ50 ng L 1). Effects of the exposures on plasma vitellogenin (Vtg) levels, EE2 and steroid hormone concentrations were investigated. The AgNP and AgNP þ EE2 exposures resulted in similar Ag concentrations in the tissues, indicating that combined exposure did not influence Ag uptake in tissues. The highest Ag concentrations were found in gills. For the Agþ exposed fish, the highest Ag concentrations were measured in the liver. Our results show dissolution processes of AgNPs in seawater, indicating that the tissue concentrations of Ag may partly originate from ionic release. Plasma EE2 concentrations and Vtg induction were similar in fish exposed to the single contaminants and the mixed contaminants, indicating that the presence of AgNPs did not significantly alter EE2 uptake. Similarly, concentrations of most steroid hormones were not significantly altered due to exposures to the combined contaminants versus the single compound exposures. However, high concentrations of AgNPs in combination with EE2 caused a drop of estrone (E1) (female fish) and androstenedione (AN) (male and female fish) levels in plasma below quantification limits. Our results indicate that the interactive effects between AgNPs and EE2 are limited, with only high concentrations of AgNPs triggering synergistic effects on plasma steroid hormone concentrations in juvenile turbots. | acceptedVersion
Показать больше [+] Меньше [-]Decreased vaccine antibody titers following exposure to multiple metals and metalloids in e-waste-exposed preschool children Полный текст
2017
Lin, Xinjiang | Xu, Xijin | Zeng, Xiang | Xu, Long | Zeng, Zhijun | Huo, Xia
We explored acquired immunity resulting from vaccination in 3 to 7-year-old children, chronically exposed to multiple heavy metals and metalloids, in an e-waste recycling area (Guiyu, China). Child blood levels of ten heavy metals and metalloids, including lead (Pb), arsenic (As), mercury (Hg), chromium (Cr), cadmium (Cd), manganese (Mn), nickel (Ni), copper (Cu), zinc (Zn) and selenium (Se), and seven vaccine antibodies (diphtheria, pertussis, tetanus, hepatitis B, Japanese encephalitis, polio, measles) were measured. The exposed group had higher levels of blood Pb, Mn, Cu, Zn and Cr compared to the reference group (P < 0.05). Levels of all vaccine antibodies in the exposed group were significantly lower than in the reference group (P < 0.01). All vaccine antibodies negatively correlated with blood concentrations of Cu, Zn and Pb, based on spearman rank correlation analysis. Multiple logistic regression and univariate analyses identified the location of residence (Guiyu), high blood Pb (>10 μg/dL) and high blood Cu and Zn (upper median value of each group) to be inversely associated with seven antibody titers. Antibody titers increased with age, BMI, high blood Mn (>15 μg/L), and high blood Cd and Ni (upper median value of each group). Results suggest multiple heavy metal and metalloid exposure, especially to Pb, Zn and Cu, may be a risk factor inhibiting the development of child immunity, resulting in decreased child antibody levels against vaccines.
Показать больше [+] Меньше [-]Contamination characteristics and source apportionment of methylated PAHs in agricultural soils from Yangtze River Delta, China Полный текст
2017
Chen, Weixiao | Wu, Xinyi | Zhang, Haiyun | Sun, Jianteng | Liu, Wenxin | Zhu, Lizhong | Li, Xiangdong | Tsang, Daniel C.W. | Tao, Shu | Wang, Xilong
Alkylated PAHs (APAHs) have been shown to be more toxic and persistent than their non-alkylated parent compounds. However, little is known about the extent of soil contamination by these pollutants. To help understand agricultural soil pollution by these compounds at a regional scale, a total of 18 methylated PAHs (MPAHs, a major class of APAHs) in 243 soil samples were analyzed. These soil samples were collected from 11 sites in the Yangtze River Delta (YRD) region, a representative fast developing area in China. The total concentration of MPAHs (∑18MPAHs) ranged from 5.5 to 696.2 ng/g dry soil, with methylnaphthalenes (M-NAPs) and methylphenanthrenes (M-PHEs) accounting for more than 70% of the compositional profile. Relatively high concentrations of ∑18MPAHs were found in Jiaxing and Huzhou areas of Zhejiang province, as well as on the border between the cities of Wuxi and Suzhou. Different MPAH groups showed dissimilar spatial distribution patterns. The spatial distribution of lower molecular weight MPAHs was related to agricultural straw burning and emissions/depositions from industrial activities, whereas that of higher molecular weight MPAHs was much more a function of the total organic carbon (TOC) content of soil. Although coal, biomass (crop straw and wood), and petroleum combustion were identified to be the major emission sources for most of the sampling sites, the areas with relatively severe pollution with ∑18MPAHs resulted from the localized hotspots of petroleum leakage. Isomeric MPAHs with methyl group substituted at 2- (β) position exhibited significantly higher concentrations than those substituted at 1- (α) position. Results of this work help to understand soil pollution by MPAHs, and are useful for designing effective strategies for pollution control so as to ensure food safety in areas with fast economic growth.
Показать больше [+] Меньше [-]Bisphenol A induces proliferative effects on both breast cancer cells and vascular endothelial cells through a shared GPER-dependent pathway in hypoxia Полный текст
2017
Xu, Fangyi | Wang, Xiaoning | Wu, Nannan | He, Shuiqing | Yi, Weijie | Xiang, Siyun | Zhang, Piwei | Xie, Xiao | Ying, Chenjiang
Based on the breast cancer cells and the vascular endothelial cells are both estrogen-sensitive, we proposed a close reciprocity existed between them in the tumor microenvironment, via shared molecular mechanism affected by environmental endocrine disruptors (EDCs). In this study, bisphenol A (BPA), via triggering G-protein estrogen receptor (GPER), stimulated cell proliferation and migration of bovine vascular endothelial cells (BVECs) and breast cancer cells (SkBr-3 and MDA-MB-231) and enhanced tumor growth in vivo. Moreover, the expression of both hypoxia inducible factor-1 alpha (HIF-1α) and vascular endothelial growth factor (VEGF) were up-regulated in a GPER-dependent manner by BPA treatment under hypoxic condition, and the activated GPER induced the HIF-1α expression by competitively binding to caveolin-1 (Cav-1) and facilitating the release of heat shock protein 90 (HSP90). These findings show that in a hypoxic microenvironment, BPA promotes HIF-1α and VEGF expressions through a shared GPER/Cav-1/HSP90 signaling cascade. Our observations provide a probable hypothesis that the effects of BPA on tumor development are copromoting relevant biological responses in both vascular endothelial and breast cancer cells.
Показать больше [+] Меньше [-]National-scale exposure prediction for long-term concentrations of particulate matter and nitrogen dioxide in South Korea Полный текст
2017
Kim, Sun Young | Song, Insang
The limited spatial coverage of the air pollution data available from regulatory air quality monitoring networks hampers national-scale epidemiological studies of air pollution. The present study aimed to develop a national-scale exposure prediction model for estimating annual average concentrations of PM10 and NO2 at residences in South Korea using regulatory monitoring data for 2010. Using hourly measurements of PM10 and NO2 at 277 regulatory monitoring sites, we calculated the annual average concentrations at each site. We also computed 322 geographic variables in order to represent plausible local and regional pollution sources. Using these data, we developed universal kriging models, including three summary predictors estimated by partial least squares (PLS). The model performance was evaluated with fivefold cross-validation. In sensitivity analyses, we compared our approach with two alternative approaches, which added regional interactions and replaced the PLS predictors with up to ten selected variables. Finally, we predicted the annual average concentrations of PM10 and NO2 at 83,463 centroids of residential census output areas in South Korea to investigate the population exposure to these pollutants and to compare the exposure levels between monitored and unmonitored areas. The means of the annual average concentrations of PM10 and NO2 for 2010, across regulatory monitoring sites in South Korea, were 51.63 μg/m3 (SD = 8.58) and 25.64 ppb (11.05), respectively. The universal kriging exposure prediction models yielded cross-validated R2s of 0.45 and 0.82 for PM10 and NO2, respectively. Compared to our model, the two alternative approaches gave consistent or worse performances. Population exposure levels in unmonitored areas were lower than in monitored areas. This is the first study that focused on developing a national-scale point wise exposure prediction approach in South Korea, which will allow national exposure assessments and epidemiological research to answer policy-related questions and to draw comparisons among different countries.
Показать больше [+] Меньше [-]Extended biotic ligand model for predicting combined Cu–Zn toxicity to wheat (Triticum aestivum L.): Incorporating the effects of concentration ratio, major cations and pH Полный текст
2017
Wang, Xuedong | Ji, Dongxue | Chen, Xiaolin | Ma, Yibing | Yang, Junxing | Ma, Jingxing | Li, Xiaoxiu
Current risk assessment models for metals such as the biotic ligand model (BLM) are usually applied to individual metals, yet toxic metals are rarely found singly in the environment. In the present research, the toxicity of Cu and Zn alone and together were studied in wheat (Triticum aestivum L.) using different Ca2+ and Mg2+ concentrations, pH levels and Zn:Cu concentration ratios. The aim of the study was to better understand the toxicity effects of these two metals using BLMs and toxic units (TUs) from single and combined metal toxicity data. The results of single-metal toxicity tests showed that toxicity of Cu and Zn tended to decrease with increasing Ca2+ or Mg2+ concentrations, and that the effects of pH on Cu and Zn toxicity were related not only to free Cu2+ and Zn2+ activity, respectively, but also to other inorganic metal complex species. For the metal mixture, Cu–Zn interactions based on free ion activities were primarily additive for the different Ca2+ and Mg2+ concentrations and levels of pH. The toxicity data of individual metals derived by the BLM, which incorporated Ca2+ and Mg2+ competition and toxicity of inorganic metal complexes in a single-metal toxicity assessment, could predict the combined toxicity as a function of TU. There was good performance between the predicted and observed effects (root mean square error [RMSE] = 7.15, R2 = 0.97) compared to that using a TU method with a model based on free ion activity (RMSE = 14.29, R2 = 0.86). The overall findings indicated that bioavailability models that include those biochemistry processes may accurately predict the toxicity of metal mixtures.
Показать больше [+] Меньше [-]Zinc oxide nanoparticle exposure triggers different gene expression patterns in maize shoots and roots Полный текст
2017
Xun, Hongwei | Ma, Xintong | Chen, Jing | Yang, Zhongzhou | Liu, Bao | Gao, Xiang | Li, Guo | Yu, Jiamiao | Wang, Li | Pang, Jinsong
The potential impacts of environmentally accumulated zinc oxide nanoparticles (nZnOs) on plant growth have not been well studied. A transcriptome profile analysis of maize exposed to nZnOs showed that the genes in the shoots and roots responded differently. Although the number of differentially expressed genes (DEGs) in the roots was greater than that in the shoots, the number of up- or down-regulated genes in both the shoots and roots was similar. The enrichment of gene ontology (GO) terms was also significantly different in the shoots and roots. The “nitrogen compound metabolism” and “cellular component” terms were specifically and highly up-regulated in the nZnO-exposed roots, whereas the categories “cellular metabolic process”, “primary metabolic process” and “secondary metabolic process” were down-regulated in the exposed roots only. Our results revealed the DEG response patterns in maize shoots and roots after nZnO exposure.
Показать больше [+] Меньше [-]Attributable risks of emergency hospital visits due to air pollutants in China: A multi-city study Полный текст
2017
Chen, Gongbo | Zhang, Yongming | Zhang, Wenyi | Li, Shanshan | Williams, Gail | Marks, Guy B. | Jalaludin, Bin | Abramson, Michael J. | Luo, Fengming | Yang, Dong | Su, Xin | Lin, Qichang | Liu, Laiyu | Lin, Jiangtao | Guo, Yuming
Air pollution is associated with risks of mortality in China, but the evidence is still limited for morbidity. This study aims to examine overall effects of ambient air pollutants on emergency hospital visits (EHVs) at the national level in China and calculate corresponding attributable risks. We collected daily data for EHVs from 33 largest hospitals in China between Oct 2013 and Dec 2014, as well as daily measurements of particulate matter (PM10 and PM2.5: particles with aerodynamic diameter < 10 μm and 2.5 μm, respectively), nitrogen dioxide (NO2) and sulphur dioxide (SO2) from 31 cities where the hospitals were located. Firstly, quasi-Poisson regression with a constrained distributed lag model (CDLM) was employed to examine city-specific associations of EHVs with each pollutant. Then, the effects at the national scale were pooled with a random-effect meta-analysis. Daily EHVs was significantly associated with a 10 μg/m3 increase in PM2.5 at lag 0–2 days [cumulative relative risk (RR) and 95% confidence intervals (CI): 1.006 (1.002, 1.009)], PM10 at lag 0–1 days [1.004 (1.002, 1.006)], NO2 at lag 0–1 days [1.015 (1.010, 1.019)] and SO2 at lag 0–2 days [1.022 (1.014, 1.030)]. The effect estimates were not modified by sex, but stronger effects were observed among children than adults. Overall, 3.34% of EHVs may result from exposure to ambient PM2.5, 3.96% to PM10, 5.90% to NO2 and 5.38% to SO2. Exposure to outdoor air pollution has acute effects on EHVs. Effective measures to control air pollution levels in China could potentially reduce demands for emergency hospital services.
Показать больше [+] Меньше [-]Reducing risk and increasing confidence of decision making at a lower cost: In-situ pXRF assessment of metal-contaminated sites Полный текст
2017
Rouillon, Marek | Taylor, Mark P. | Dong, Chenyin
This study evaluates the in-situ use of field portable X-ray Fluorescence (pXRF) for metal-contaminated site assessments, and assesses the advantages of increased sampling to reduce risk, and increase confidence of decision making at a lower cost. Five metal-contaminated sites were assessed using both in-situ pXRF and ex-situ inductively coupled plasma mass spectrometry (ICP–MS) analyses at various sampling resolutions. Twenty second in-situ pXRF measurements of Mn, Zn and Pb were corrected using a subset of parallel ICP–MS measurements taken at each site. Field and analytical duplicates revealed sampling as the major contributor (>95% variation) to measurement uncertainties. This study shows that increased sampling led to several benefits including more representative site characterisation, higher soil-metal mapping resolution, reduced uncertainty around the site mean, and reduced sampling uncertainty. Real time pXRF data enabled efficient, on-site decision making for further judgemental sampling, without the need to return to the site. Additionally, in-situ pXRF was more cost effective than the current approach of ex-situ sampling and ICP–MS analysis, even with higher sampling at each site. Lastly, a probabilistic site assessment approach was applied to demonstrate the advantages of integrating estimated measurement uncertainties into site reporting.
Показать больше [+] Меньше [-]Arbuscular mycorrhiza formation and its function under elevated atmospheric O3: A meta-analysis Полный текст
2017
Wang, Shuguang | Augé, Robert M. | Toler, Heather D.
We quantitatively evaluated the effects of elevated O3 on arbuscular mycorrhiza (AM) formation and on AM role in promoting plant growth in regard to several moderating variables (O3 levels, O3 exposure duration, plant types, AM fungi family, and additional stress) by means of meta-analysis of published data. The analysis consisted of 117 trials representing 20 peer-reviewed articles and 16 unpublished trials. Relative to non-mycorrhizal controls, AM inoculation did not significantly alter plant growth (shoot biomass, root biomass, total biomass and plant height) when O3 concentration was less than 80 ppb, but at concentrations above 80 ppb symbiosis was associated with increases of 68% in shoot biomass and 131% in root biomass. AM effects on plant growth were affected by the duration of O3 exposure but did not differ much with AM fungi taxa or plant type. AM symbiosis has also led to higher yields under O3 stress, relative to the non-mycorrhizal plants, and the AM effects have been more pronounced as O3 concentration increases. As with biomass, AM effects on yield have been affected by the duration of O3 exposure, with the greatest increase (100%) occurring at 61–90 d. AM-induced promotion of yield differed with fungal species but not with plant type or other abiotic stress. Colonization of roots by AM fungi has been negatively affected by elevated O3 compared to ambient O3; total mycorrhizal colonization rate (MCR), arbuscular MCR, vesicular MCR and hyphal coil MCR declined as O3 levels rose. AM colonization rates were affected by duration of O3 exposure, plant type, AM fungal taxa and other concurrent stresses in most cases. The analysis showed that AM inoculation has the potential to ameliorate detrimental effects of elevated O3 on plant growth and productivity, despite colonization rates being negatively affected by elevated O3.
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