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Oxidative stress parameters, DNA damage and expression of HSP70 and MT in midgut of Trachyderma hispida (Forskål, 1775) (Coleoptera: Tenebrionidae) from a textile industry area Полный текст
2020
The textile mill industry is one of the major sources of pollution and contributors of metal contaminants to the environment. At the same time, the industry is important for global economy. Pollution caused by the textile industry is characteristic due to a unique set of potentially toxic substances. Darkling beetles (Coleoptera, Tenebrionidae), which live in all biogeographical regions, are especially common in soil quality and soil degradation studies. Our study was designed to assess long-term effects of textile industry (which generates specific pollution) on soil organisms, namely Trachyderma hispida. We especially wanted to find out what changes allow the species to survive and adapt to these specific conditions. Energy-dispersive X-ray spectroscopy of soil and midgut tissues of T. hispida sampled from a polluted site in the Edku textile industrial area in Egypt revealed a high accumulation of chemical elements, compared to a reference site. The concentration of elements in soil was well correlated with their concentration in the midgut of insects. Activity of superoxide dismutase, catalase, ascorbate peroxidase and glutathione S-transferase were negatively correlated with concentration of elements in soil and in the midgut. Meanwhile, malondialdehyde concentration in the midgut revealed an opposite tendency. DNA damage and expression of stress proteins, (HSP70 and metallothionein - MT) were elevated in insects from the polluted site. The activity of textile industry in the area of Edku undoubtedly causes an increase of soil pollution and, in consequence, causes a number of changes in the bodies of organisms living in these areas, including T. hispidus. Therefore, it is necessary to find a solution which limits the emission of waste from the textile industry, as well as to design modern strategies of processing, storing and utilizing it.
Показать больше [+] Меньше [-]Urinary copper, systemic inflammation, and blood lipid profiles: Wuhan-Zhuhai cohort study Полный текст
2020
Copper have been reported to be associated with metabolic diseases. However, results on copper exposure with blood lipid profiles are inconsistent, and the underlying mechanisms of this association remain unclear. This study focused on investigating associations between urinary copper and blood lipid profiles; and exploring the potential role of systemic inflammation in such relationships. Concentrations of urinary copper, plasma C-reactive protein (CRP), and four blood lipid parameters (e.g., Total cholesterol [TC], triglycerides [TG], low-density lipoprotein cholesterol [LDL-C], and high-density lipoprotein cholesterol [HDL-C]) were measured in the adult participants from Wuhan-Zhuhai cohort. The associations between copper, CRP, and four blood lipids were assessed by the multivariable linear regression models, and the 3D mesh graphs was used to examine the joint effects of copper exposure and CRP on four blood lipid parameters. In addition, we used mediation analysis to investigate the mediated effects of CRP in the relationships between copper exposure and blood lipid profiles. Each 1% increase in urinary copper was statistically significantly associated with a 5.32% (95% CI: 2.48%, 8.24%) increase in TG after adjusting for the confounders (P < 0.05). No significant associations were observed between urinary copper and the other three blood lipid parameters (all P > 0.05). In addition, urinary copper increased monotonically with plasma CRP elevation, which in turn, was positively associated with TC, TG, and LDL-C and negatively related to HDL-C (all P < 0.05). Results from 3D mesh graphs demonstrated that increased levels of plasma CRP with higher urinary copper corresponded to higher TC, TG, LDL-C, and lower HDL-C concentrations. Mediation analysis observed that CRP mediated 6.27% in the relationships of urinary copper and TG. These findings suggest that systemic inflammation partly mediated the association between copper exposure and abnormal blood lipid, and may contribute to the development of dyslipidemias.
Показать больше [+] Меньше [-]Risks of floating microplastic in the global ocean Полный текст
2020
Risks of floating microplastic in the global ocean Полный текст
2020
Despite the ubiquitous and persistent presence of microplastic (MP) in marine ecosystems, knowledge of its potential harmful ecological effects is low. In this work, we assessed the risk of floating MP (1 μm–5 mm) to marine ecosystems by comparing ambient concentrations in the global ocean with available ecotoxicity data. The integration of twenty-three species-specific effect threshold concentration data in a species sensitivity distribution yielded a median unacceptable level of 1.21 ∗ 10⁵ MP m⁻³ (95% CI: 7.99 ∗ 10³–1.49 ∗ 10⁶ MP m⁻³). We found that in 2010 for 0.17% of the surface layer (0–5 m) of the global ocean a threatening risk would occur. By 2050 and 2100, this fraction increases to 0.52% and 1.62%, respectively, according to the worst-case predicted future plastic discharge into the ocean. Our results reveal a spatial and multidecadal variability of MP-related risk at the global ocean surface. For example, we have identified the Mediterranean Sea and the Yellow Sea as hotspots of marine microplastic risks already now and even more pronounced in future decades.
Показать больше [+] Меньше [-]Risks of floating microplastic in the global ocean Полный текст
2020
Everaert, G. | De Rijcke, M. | Lonneville, B. | Janssen, C.R. | Backhaus, T. | Mees, J. | van Sebille, E. | Koelmans, A.A. | Catarino, A.I. | Vandegehuchte, M.
Despite the ubiquitous and persistent presence of microplastic (MP) in marine ecosystems, knowledge of its potential harmful ecological effects is low. In this work, we assessed the risk of floating MP (1 μm – 5 mm) to marine ecosystems by comparing ambient concentrations in the global ocean with available ecotoxicity data. The integration of twenty-three species-specific effect threshold concentration data in a species sensitivity distribution yielded a median unacceptable level of 1.21 * 105 MP m-³ (95% CI: 7.99 * 103 – 1.49 * 106 MP m-³). We found that in 2010 for 0.17% of the surface layer (0 – 5 m) of the global ocean a threatening risk would occur. By 2050 and 2100, this fraction increases to 0.52% and 1.62%, respectively, according to the worst-case predicted future plastic discharge into the ocean. Our results reveal a spatial and multidecadal variability of MP-related risk at the global ocean surface. For example, we have identified the Mediterranean Sea and the Yellow Sea as hotspots of marine microplastic risks already now and even more pronounced in future decades.
Показать больше [+] Меньше [-]GAPS-megacities: A new global platform for investigating persistent organic pollutants and chemicals of emerging concern in urban air Полный текст
2020
Saini, Amandeep | Harner, Tom | Chinnadhurai, Sita | Schuster, Jasmin K. | Yates, Alan | Sweetman, Andrew | Aristizabal-Zuluaga, Beatriz H. | Jiménez, Begoña | Manzano, Carlos A. | Gaga, Eftade O. | Stevenson, Gavin | Falandysz, Jerzy | Ma, Jianmin | Miglioranza, Karina S.B. | Kannan, Kurunthachalam | Tominaga, Maria | Jariyasopit, Narumol | Rojas, Nestor Y. | Amador-Muñoz, Omar | Sinha, Ravindra | Alani, Rose | Suresh, R. | Nishino, Takahiro | Shoeib, Tamer
A pilot study was initiated in 2018 under the Global Atmospheric Passive Sampling (GAPS) Network named GAPS-Megacities. This study included 20 megacities/major cities across the globe with the goal of better understanding and comparing ambient air levels of persistent organic pollutants and other chemicals of emerging concern, to which humans residing in large cities are exposed. The first results from the initial period of sampling are reported for 19 cities for several classes of flame retardants (FRs) including organophosphate esters (OPEs), polybrominated diphenyl ethers (PBDEs), and halogenated flame retardants (HFRs) including new flame retardants (NFRs), tetrabromobisphenol A (TBBPA) and hexabromocyclododecane (HBCDD). The two cities, New York (USA) and London (UK) stood out with ∼3.5 to 30 times higher total FR concentrations as compared to other major cities, with total concentrations of OPEs of 15,100 and 14,100 pg/m³, respectively. Atmospheric concentrations of OPEs significantly dominated the FR profile at all sites, with total concentrations in air that were 2–5 orders of magnitude higher compared to other targeted chemical classes. A moderately strong and significant correlation (r = 0.625, p < 0.001) was observed for Gross Domestic Product index of the cities with total OPEs levels. Although large differences in FR levels were observed between some cities, when averaged across the five United Nations regions, the FR classes were more evenly distributed and varied by less than a factor of five. Results for Toronto, which is a ‘reference city’ for this study, agreed well with a more in-depth investigation of the level of FRs over different seasons and across eight sites representing different urban source sectors (e.g. traffic, industrial, residential and background). Future sampling periods under this project will investigate trace metals and other contaminant classes, linkages to toxicology, non-targeted analysis, and eventually temporal trends. The study provides a unique urban platform for evaluating global exposome.
Показать больше [+] Меньше [-]Exposure to ambient air pollution and blood lipids in children and adolescents: A national population based study in China Полный текст
2020
Gui, Zhao-Huan | Yang, Bo-Yi | Zou, Zhi-Yong | Ma, Jun | Jing, Jin | Wang, Hai-Jun | Dong, Guang-Hui | Ma, Yinghua | Guo, Yu-Ming | Chen, Ya-Jun
Few studies have explored the links of air pollution and childhood lipid profiles and dyslipidemias. We aimed to explore this topic in Chinese children and adolescents. This study included 12,814 children aged 7–18 years who participated in a national survey in 2013. Satellite-based spatial-temporal model was used to predict 3-y (2011–2013) average particles with diameters ≤ 1.0 μm (PM₁), ≤2.5 μm (PM₂.₅), ≤10 μm (PM₁₀), and nitrogen dioxide (NO₂) concentrations. Generalized linear mixed models were employed to evaluate the relationships of air pollution and total cholesterol (TC), triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), and dyslipidemias. Every 10 μg/m³ increase in PM₁, PM₂.₅, PM₁₀, and NO₂ was related to increases of 6.20% [95% confidence interval (CI): 2.44, 10.10], 5.31% (95%CI: 0.41, 10.44), 3.49% (95%CI: 0.97, 6.08), and 5.25% (95%CI: 1.56, 9.07) in TC, respectively. The odds ratio of hypercholesterolemia associated with a 10 μg/m³ increase in PM₁, PM₂.₅, and NO₂ was 2.15 (95%CI: 1.27, 3.65), 1.70 (95%CI: 1.12, 2.60), and 1.43 (95%CI: 1.05, 1.93), respectively. No associations were found for air pollution and other blood lipids. Long-term PM₁, PM₂.₅, PM₁₀, and NO₂ exposures were positively associated with TC levels and risk of hypercholesterolemia in children and adolescents.
Показать больше [+] Меньше [-]Microbial driven iron reduction affects arsenic transformation and transportation in soil-rice system Полный текст
2020
The microbe-driven iron cycle plays an important role in speciation transformation and migration of arsenic (As) in soil-rice systems. In this study, pot experiments were used to investigate the effect of bacterial iron (Fe) reduction processes in soils on As speciation and migration, as well as on As uptake in soil-rice system. During the rice growth period, pH and electrical conductivity (EC) in soil solutions initially increased and then decreased, with the ranges of 7.4–8.8 and 116.3–820 mS cm⁻¹, respectively. The concentrations of Fe, total As and As(III) showed an increasing trend in the rhizosphere and non-rhizosphere soil solutions with the increasing time. Fe concentrations were significantly positively correlated with total As and As(III) concentrations (***p < 0.001) in the soil solutions. The abundances of the arsenate reductase gene (arsC) and the As(III) S-adenosylmethionine methyltransferase gene (arsM) in rhizosphere soils were higher than those in non-rhizosphere soils, while the abundance of the Fe-reducing bacteria (Geo) showed an opposite trend. Moreover, it showed that the Geo abundance was significantly positively correlated with that of the arsC (***p < 0.001) and arsM (**p < 0.01) genes, respectively. The abundances of Geo, arsC and arsM genes were significantly positively correlated with the concentrations of Fe, total As and As(III) in the soil solutions (*p < 0.05). Moreover, the abundances of arsC and arsM genes were significantly negatively correlated with total As and As(III) in rice grains (*P < 0.05). These results showed that the interaction of bacterial Fe reduction process and radial oxygen loss from roots promoted the reduction and methylation of As, and then decreased As uptake by rice, which provided a theoretical basis for alleviating As pollution in paddy soils.
Показать больше [+] Меньше [-]Acropetal translocation of phenanthrene in wheat seedlings: Xylem or phloem pathway? Полный текст
2020
Due to the potential toxicity of polycyclic aromatic hydrocarbons (PAHs) to humans, the uptake and translocation of PAHs in food crops have gained much attention. However, it is still unclear whether phloem participates in the acropetal translocation of PAHs in plants. Herein, the evidence for acropetal translocation of phenanthrene (a model PAH) via phloem is firstly tested. Wheat (Triticum aestivum L.) new leaves contain significantly higher phenanthrene concentration than old leaves (P < 0.05), and the inhibitory effect on phenanthrene translocation is stronger in old leaves after abscisic acid and polyvinyl alcohol (two common transpiration inhibitors) application. Phenanthrene concentration in xylem sap is slightly higher than in phloem sap. Ring-girdling treatment can significantly reduce phenanthrene concentration in castor bean (Ricinus communis L.) leaves. Two-photon fluorescence microscope images indicate a xylem-to-phloem and acropetal phloem translocation of phenanthrene in castor bean stem. Therefore, phloem is involved in the acropetal translocation of phenanthrene in wheat seedlings, especially when the xylem is not mature enough in scattered vascular bundle plants. Our results provide a deeper understanding of PAH translocation in plants, which have significant implications for food safety and phytoremediation enhancement of PAH-contaminated soil and water.
Показать больше [+] Меньше [-]Wavelength-specific artificial light disrupts molecular clock in avian species: A power-calibrated statistical approach Полный текст
2020
Nighttime lighting is an increasingly important anthropogenic environmental stress on plants and animals. Exposure to unnatural lighting environments may disrupt the circadian rhythm of organisms. However, the sample size of relevant studies, e.g. disruption of the molecular circadian clock by light pollution, was small (<10), which led to low statistical power and difficulties in replicating prior results. Here, we developed a power-calibrated statistical approach to overcome these weaknesses. The results showed that the effect size of 2.48 in clock genes expression induced by artificial light would ensure the reproducibility of the results as high as 80%. Long-wavelength light (560–660 nm) entrained expressions of the positive core clock genes (e.g. cClock) and negative core clock genes (e.g. cCry1, cPer2) in robust circadian rhythmicity, whereas those clock genes were arrhythmic in short-wavelength light (380–480 nm). Further, we found artificial light could entrain the transcriptional-translational feedback loop of the molecular clock in a wavelength-dependent manner. The expression of the positive core clock genes (cBmal1, cBmal2 and cClock), cAanat gene and melatonin were the highest in short-wavelength light and lowest in long-wavelength light. For the negative regulators of the molecular clock (cCry1, cCry2, cPer2 and cPer3), the expression of which was the highest in long-wavelength light and lowest in short-wavelength light. Our statistical approach opens new opportunities to understand and strengthen conclusions, comparing with the studies with small sample sizes. We also provide comprehensive insight into the effect of wavelength-specific artificial light on the circadian rhythm of the molecular clock in avian species. Especially, the global lighting is shifting from “yellow” sodium lamps, which is more like the long-wavelength light, toward short-wavelength light (blue light)-enriched “white” light-emitting diodes (LEDs).
Показать больше [+] Меньше [-]Contaminant screening and tissue distribution in the critically endangered Brazilian guitarfish Pseudobatos horkelii Полный текст
2020
Elasmobranchs are particularly prone to accumulating contaminants due to their life history patterns and relatively high trophic position. However, several compounds, especially contaminants of emerging concern, have still not been well studied in this group. Here, we aimed to determine the occurrence and concentrations of several inorganic and organic contaminants in different tissues of the Brazilian guitarfish Pseudobatos horkelii. This species is a critically endangered species, endemic from the Southwest Atlantic which uses southern Brazilian waters as a nursery habitat. Polycyclic aromatic hydrocarbons (PAHs), emerging pesticides, pharmaceutical and personal care products (PPCPs) and trace metals were determined in five biological tissues in order to assess the accumulation and organotropism of these compounds. Except for chlorothalonil and triclosan, all compounds were detected in, at least, one tissue, mostly in liver samples. All compounds differed among tissues, with liver presenting the higher concentrations of several contaminants, followed by muscle and gills. PAHs and PPCPs were the most detected analytes and presented the highest concentrations among tissues. Diclofenac levels were determined, for the first time in elasmobranchs, and were relatively high, when compared to other fishes. Finally, relatively high concentrations of PAHs, dichlofluanid and octocrylene in muscle might be suggestive of chronic exposure, presenting also human health implications. Regarding trace metals, contrary to most elasmobranch studies, Hg levels were low in all tissues, whereas Cd and Pb here higher in liver, and gills and blood samples, respectively. Our results indicate that P. horkelii is exposed to several organic and inorganic which might affect this species in a long-term scale. Concerning the determination of emerging contaminants, it is likely that other elasmobranchs are also exposed to these compounds and special attention should be given to this issue in order to predict future effects on this group.
Показать больше [+] Меньше [-]Plutonium isotopes in Northern Xinjiang, China: Level, distribution, sources and their contributions Полный текст
2020
Plutonium in the environment has drawn significant attentions due to its radiotoxicity in high concentration and source term linked with nuclear accidents and contaminations. The isotopic ratio of plutonium is source dependent and can be used as a fingerprint to discriminate the sources of radioactive contaminant. ²³⁹Pu, ²⁴⁰Pu and ¹³⁷Cs in surface soil and soil cores collected from Northern Xinjiang were determined in this work. The concentrations of ²³⁹,²⁴⁰Pu and ¹³⁷Cs are in the range of 0.06–1.20 Bq kg⁻¹, and <1.0–31.4 Bq kg⁻¹ (decay corrected to Sep. 2017), respectively, falling in the ranges of global fallout in this latitude zone. The ²⁴⁰Pu/²³⁹Pu atomic ratios of 0.118–0.209 and ²³⁹,²⁴⁰Pu/¹³⁷Cs activity ratios of 0.039–0.215 were measured. Among the investigated sites, distinctly lower ²⁴⁰Pu/²³⁹Pu atomic ratios of 0.118–0.133 and higher ²³⁹,²⁴⁰Pu/¹³⁷Cs activity ratios of 0.065–0.215 compared to the global fallout values were observed in the northwest part, indicating a significant contribution from other source besides the global fallout. This extra source is mainly attributed to the releases of atmospheric nuclear weapons testing at Semipalatinsk Nuclear Test Site, which was transported by the west and northwest wind through the river valley among mountains in this region. This contribution is estimated to account for 28–43% of the global fallout in the northwest part of Northern Xinjiang. The contribution from the Chinese atmospheric nuclear weapons testing to this region is negligible due to the lack of appropriate wind direction to transport the radioactive releases to this region.
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