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Assessment of O3-induced yield and economic losses for wheat in the North China Plain from 2014 to 2017, China
2020
Hu, Tingjian | Liu, Shuo | Xu, Yansen | Feng, Zhaozhong | Calatayud, Vicent
Tropospheric ozone (O₃) is a pollutant of widespread concern in the world and especially in China for its negative effects on agricultural crops. For the first time, yield and economic losses of wheat between 2014 and 2017 were estimated for the North China Plain (NCP) using observational hourly O₃ data from 312 monitoring stations and exposure-response functions based on AOT40 index (accumulated hourly O₃ concentration above 40 ppb) from a Chinese study. AOT40 values from 2014 to 2017 during the wheat growing seasons (75-days, 44 before and 30 after mid-anthesis) ranged from 3.1 to 14.9 ppm h, 4.9–17.5 ppm h, 7.3–17.6 ppm h, and 0.5–18.6 ppm h, respectively. The highest AOT40 values were observed in the Beijing-Tianjin-Hebei region. The values of relative yield losses from 2014 to 2017 were in the ranges of 6.4–30.5%, 10.0–35.8%, 14.9–34.1%, and 21.6–38.2%, respectively. The total wheat production losses in NCP for 2014–2017 accounted for 18.5%, 22.7%, 26.2% and 30.8% in the whole production, while the economic losses amounted to 6,292 million USD, 8,524 million USD, 10,068 million USD, and 12,404 million USD, respectively. The important impact of O₃ in this area, which is of global importance, should be considered when assessing wheat yield production. Our results also show an increasing trend in AOT40, relative yield loss, total crop production loss and economic loss in the four consecutive years.
Mostrar más [+] Menos [-]Maternal exposure to air pollution and risk of autism in children: A systematic review and meta-analysis
2020
Chun, HeeKyoung | Leung, Cheryl | Wen, Shi Wu | McDonald, Judy | Shin, Hwashin H.
The number of children diagnosed with autism spectrum disorder (ASD) has been increasing. Previous studies suggested potential association between pregnancy air pollution exposure and ASD. This systematic review and meta-analysis is intended to summarize the association between maternal exposure to outdoor air pollution and ASD in children by trimester based on recent studies.A systematic literature search in 3 databases (Medline, Embase, and Web of Science) was performed using subject headings related to ASD and air pollution since 2007. Eligible studies were screened and evaluated based on predetermined criteria. For meta-analyses, the studies were grouped by air pollutant and exposure time (prenatal period and trimesters). Within-group studies were standardized by log odds ratio (OR) and then combined by three meta-analysis methods: frequentist fixed and random effects models, and Bayesian random effects model.Initial search identified 1564 papers, of which 25 studies remained for final analysis after duplicates and ineligible studies were removed. Of the 25 studies, 13, 14, 12, and 7 studies investigated ASD in children associated with PM2.5, PM10, NO2, and ozone, respectively. The frequentist and Bayesian random effects models resulted in different statistical significance. For prenatal period, frequentist meta-analysis returned significant pooled ORs with 95% confidence intervals, 1.06(1.01,1.11) for PM2.5 and 1.02(1.01,1.04) for NO2, whereas Bayesian meta-analysis showed similar ORs with wider 95% posterior intervals, 1.06(1.00,1.13) for PM2.5 and 1.02(1.00,1.05) for NO2. Third trimester appeared to have higher pooled ORs for PM2.5, PM10, and ozone, but patterns in the time-varying associations over the trimester were inconsistent.For positive association between maternal exposure to ambient air pollution and ASD in children, there is some evidence for PM2.5, weak evidence for NO2 and little evidence for PM10 and ozone. However, patterns in associations over trimesters were inconsistent among studies and among air pollutants.
Mostrar más [+] Menos [-]Transfer of dechlorane plus between human breast milk and adipose tissue and comparison with legacy lipophilic compounds
2020
Pan, Hai-Yan | Li, Ji-Fang-Tong | Li, Xing-Hong | Yang, You-Lin | Qin, Zhan-Fen | Li, Jin-Bo | Li, Yuan-Yuan
In this study, levels of dechlorane plus (DP) in breast milk and matched adipose tissue samples were measured from 54 women living in Wenling, China. Polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) were measured simultaneously for comparison. The levels of ∑DPs/∑PBDEs varied from less than one to several dozens of ng g⁻¹ lipid weight (lw) in matrices and the levels of ∑PCBs varied between several to hundreds of ng g⁻¹ lw. In the same matrix, ∑DPs and ∑PCBs/∑PBDEs showed a significant relationship (p < 0.05), indicating that they shared common sources. Accordingly, there was a strong association of lipid-adjusted concentrations of individual compounds (BDE-209 excluded) between matrices (p < 0.001), suggesting that breast milk could be a proxy for adipose tissue in human bioburden monitoring of these compounds. The predicted lipid-adjusted milk/adipose ratios varied from 0.62 to 1.5 but showed significant differences (p<0.001) between compounds, suggesting a compound-specific transfer between milk lipids and adipose tissue lipids. Specifically, the milk/adipose ratios for syn-DP and anti-DP (−1.40 and 1.3, respectively) were significantly higher than those of CB congeners and hexa/hepta-BDE congeners (p < 0.05). In addition, unlike PCBs/PBDEs (excluding BDE-209), DP’s hydrophobicity might not be responsible for its preferable distribution in milk lipids. Instead, the interaction with nonlipid factors played a key role. The fraction of anti-DP between the two kinds of matrices was not significantly different, suggesting that the biochemical transfer processes may not be efficient enough to distinguish DP isomers. Nevertheless, the congener patterns of PCBs/PBDEs gave a clue about the compound-specific transfer between milk and adipose tissue. To our knowledge, this is the first to report the relationships of DP between adipose tissue and breast milk. These results could provide useful and in-depth information on biomonitoring of DP and facilitate the understanding of the accumulation and excretion potentials of DP and its distribution-related mechanism in humans.
Mostrar más [+] Menos [-]Upregulation of miR-200c-3p induced by NaF promotes endothelial apoptosis by activating Fas pathway
2020
Jiang, Yuting | Yang, Yanmei | Zhang, Chengzhi | Huang, Wei | Wu, Liaowei | Wang, Jian | Su, Mengyao | Sun, Dianjun | Gao, Yanhui
Fluoride has been considered as a risk factor of cardiovascular disease due to its endothelial toxicology. However, the mechanism underlying the endothelial toxicity of fluoride has not been clearly illustrated. MiR-200c-3p was strongly linked with endothelial function and its level is increased in serum of fluorosis patients, but it is unclear the role of miR-200c-3p in the fluoride induced endothelial dysfunction. In this study, we confirmed that fluoride exposure induced the apoptosis of endothelial cells both in established rats model and cultured human umbilical vein endothelial cells (HUVECs). And miR-200c-3p was found to be upregulated in NaF treated HUVECs. Fluoride stimulation increased caspase-dependent apoptosis through miR-200c-3p upregulation, with repressing expression of its target gene Fas-associated phosphatase 1 (Fap-1), which functioned as Fas inhibitor. This resulted in activation of Fas-associated extrinsic apoptosis via interaction with increased Fas, Fadd, Cleaved Caspase-8 and Cleaved Caspase-3. The activation of Fas-associated extrinsic apoptosis was abrogated by miR-200c-3p inhibitor. Furthermore, the antiapoptotic effect of downregulated miR-200c-3p was restored by Fap-1 siRNA. These results suggested a determinant role of the miR-200c-3p/Fap-1 axis in fluoride induced endothelial apoptosis.
Mostrar más [+] Menos [-]Fumonisins B1 exposure triggers intestinal tract injury via activating nuclear xenobiotic receptors and attracting inflammation response
2020
Li, Xinran | Cao, Changyu | Zhu, Xingyi | Li, Xiaowen | Wang, Kai
Fumonisins (FBs) are mycotoxins that are widely distributed in crops and feed, and ingestion of FBs -contaminated crops is harmful to animal health. Furthermore, it is unknown if Fumonisins B1 (FB1) can cause intestinal toxicity. To investigate FB1-induced intestinal toxicity, mice were treated with 0 or 5 mg/kg FB1 by gavage administration for 42 days. Histopathology indicated that FB1 exposure caused proliferation of intestinal epithelial cells, intestinal villi and epithelial layer shedding, intestinal gland atrophy, and necrosis. Notably, FB1 interfered with nuclear xenobiotic receptors (NXR) homeostasis by regulating the level of aryl hydrocarbon receptor (AHR), constitutive androstane receptor (CAR), pregnane X receptor (PXR) and downstream target genes (CYP450s). Moreover, abnormal expression of inflammatory cytokines (IL-1β, IL-2, IL-4, IL-10, and TNF-α) indicated the occurrence of inflammation. The present study provides new insights regarding the mechanism of FB1-induced intestinal toxicity through activating the NXR system and by triggering inflammatory responses in the intestinal tract in mice.
Mostrar más [+] Menos [-]Evidence-based assessment on environmental mixture using a concentration-dependent transcriptomics approach
2020
Wang, Pingping | Xia, Pu | Wang, Zhihao | Zhang, Xiaowei
Development of new approach methodologies is urgently needed to characterize the likelihood that complex mixtures of chemicals affect water quality. Omics advances in ecotoxicology allow assessment on a broadest coverage of disrupted biological pathway by mixtures. Here the usefulness of transcriptomic analyses for evaluation of combined effects and identification of main effect components are explored. Two artificial mixtures (Mix 1 and Mix 2) were tested by a concentration-dependent reduced zebrafish transcriptome (CRZT) approach and toxicity bioassays using zebrafish embryos. Then, the toxicities and transcriptomic effects of 12 component chemicals on embryos were incorporated into additivity models to characterize the combined effects of chemicals in mixtures and to identify the main bioactive compounds. Mix 1 and Mix 2 displayed similar embryo toxicities (LD₅₀: 6.6 μM and 8.7 μM, respectively), however, Mix 2 elicited broader biological process perturbations and 5-fold higher transcriptome potency (point of departure eliciting a 20% pathway response, PODₚₐₜₕ₂₀) than Mix 1. The predicted mixture toxicities derived from additivity expectations deviated by 2-fold or less from the measured embryo toxicities except for the Jaw defect endpoint; most biological processes deviated by 3-fold or less. Finally, diclofenac (DFC) and propiconazole (PCZ) were identified as the main contributing components (≥80% explanation) to the embryo toxicity and biological process perturbations by Mix 1. While DFC and chlorophene (CLP) explained up to 80% of the embryo toxicities and biological effects of Mix 2 associated with development and Metabolism processes. The CRZT approach provides a powerful tool for assessment of biological pathways perturbed by chemicals in mixtures and for identification of main bioactive compounds.
Mostrar más [+] Menos [-]Upcycling of waste polyethylene terephthalate plastic bottles into porous carbon for CF4 adsorption
2020
Yuan, Xiangzhou | Cho, Moon-Kyung | Lee, Jong Gyu | Choi, Seung Wan | Lee, Ki Bong
Thermo-chemical processes for converting plastic wastes into useful materials are considered promising technologies to mitigate the environmental pollution caused by plastic wastes. In this study, polyethylene terephthalate (PET) plastic wastes were used to develop cost-effective and value-added porous carbons; the developed porous carbons were subsequently tested for capturing CF₄, a greenhouse gas with a high global-warming potential. The activation temperature was varied from 600 °C to 1000 °C and the mass ratio of KOH/carbon ranged from 1 to 3 in the preparation process and their effects on the textural properties and CF₄-capture performance of the PET plastic waste-derived porous carbons were investigated. The CF₄-adsorption uptake was dictated by the specific surface area and pore volume of narrow micropores less than 0.9 nm in diameter. PET-K(2)700, which was developed by KOH activation at 700 °C and KOH/carbon mass ratio of 2, showed the highest CF₄-adsorption uptake of 2.43 mmol g⁻¹ at 25 °C and 1 atm. Also, the CF₄-adsorption data were fitted well with the Langmuir isotherm model and pseudo second-order kinetic model. The PET plastic waste-derived porous carbons exhibited a high CF₄ uptake, good CF₄/N₂ selectivity at relatively low CF₄ pressures, easy regeneration, rapid adsorption/desorption kinetics, and excellent recyclability, which are promising for practical CF₄-capture applications.
Mostrar más [+] Menos [-]Selecting the best stabilization/solidification method for the treatment of oil-contaminated soils using simple and applied best-worst multi-criteria decision-making method
2020
Kujlu, Rahele | Moslemzadeh, Mehrdad | Rahimi, Somayeh | Aghayani, Ehsan | Ghanbari, Farshid | Mahdavianpour, Mostafa
Oil-contaminated soils resulted from drilling activities can cause significant damages to the environment, especially for living organisms. Treatment and management of these soils are the necessity for environmental protection. The present study investigates the field study of seven oil-contaminated soils treated by different stabilization/solidification (S/S) methods, and the selection of the best treated site and treatment method. In this study, first, the ratios of consumed binders to the contaminated soils (w/w) and the treatment times for each unit of treated soils were evaluated. The ratios of consumed binders to the contaminated soils were between 6 and 10% and the treatment times for each unit of treated soils were between 4.1 and 18.5 min/m³. Physicochemical characteristics of treated soils were also determined. Although S/S methods didn’t change the water content of treated soils, they increased the porosity of soils. Unexpectedly, the cement-based S/S methods didn’t increase the pH of the treated soils. The highest and the lowest leaching of petroleum hydrocarbons was belonging to S/S using diatomaceous earth (DE) and the combination of Portland cement, sodium silicate and DE (CS-DE), respectively. The best acid neutralization capacity was obtained for soils treated using the combination of Portland cement and sodium silicate (CS). Based on the best-worst multi-criteria decision-making method (BWM-MCDM), the soils treated using CS-DE was select as the best. The BWM-MCDM can be used as an effective tool for the selection of the best alternative in all areas of environmental decontamination.
Mostrar más [+] Menos [-]Waterborne and dietary accumulation of well-dispersible hematite nanoparticles by zebrafish at different life stages
2020
Huang, Bin | Cui, Yu-Qing | Guo, Wen-Bo | Yang, Liuyan | Miao, Ai-Jun
The widespread use of nanoparticles (NPs) has drawn considerable attention because of their potential toxicity and the environmental consequences thereof. However, the effects of the exposure route and life stage of an organism on the bioaccumulation and toxicity of NPs are largely unknown. In the present study, we investigated the accumulation kinetics (uptake, assimilation, and efflux) and tissue distribution of waterborne and dietary hematite NPs (HemNPs) during three life stages (embryo, larva, and adult) of the zebrafish Danio rerio. For all zebrafish life stages, the waterborne accumulation of well-dispersed HemNPs increased linearly with exposure time but decreased after reaching a maximum. The increase in HemNPs accumulation followed the order embryo > larva > adult. Compared with the waterborne route, the dietary accumulation of HemNPs in larval and adult zebrafish fluctuated, reaching a maximum after each food refreshment and then decreasing until the next food addition. Similar to waterborne exposure, adult fish accumulated less dietary HemNPs than did larvae. Nevertheless, dietary HemNPs mostly accumulated in the intestinal tract, with smaller amounts in the truncus, head, and gills, as compared with their waterborne counterparts. Moreover, in the gonad no dietary HemNPs were detected whereas accumulation via waterborne HemNPs was significant. Despite the low assimilation efficiency of dietary HemNPs, biodynamic modeling showed that the diet was the main source of particle accumulation in zebrafish. Thus, both the life stage and the exposure route should be considered in evaluations of the environmental risks of NPs.
Mostrar más [+] Menos [-]Particulate matter (PM10) enhances RNA virus infection through modulation of innate immune responses
2020
Miśra, R̥cā | Krishnamoorthy, Pandikannan | Gangamma, S. | Raut, Ashwin Ashok | Kumar, Himanshu
Sensing of pathogens by specialized receptors is the hallmark of the innate immunity. Innate immune response also mounts a defense response against various allergens and pollutants including particulate matter present in the atmosphere. Air pollution has been included as the top threat to global health declared by WHO which aims to cover more than three billion people against health emergencies from 2019 to 2023. Particulate matter (PM), one of the major components of air pollution, is a significant risk factor for many human diseases and its adverse effects include morbidity and premature deaths throughout the world. Several clinical and epidemiological studies have identified a key link between the PM existence and the prevalence of respiratory and inflammatory disorders. However, the underlying molecular mechanism is not well understood. Here, we investigated the influence of air pollutant, PM₁₀ (particles with aerodynamic diameter less than 10 μm) during RNA virus infections using Highly Pathogenic Avian Influenza (HPAI) – H5N1 virus. We thus characterized the transcriptomic profile of lung epithelial cell line, A549 treated with PM₁₀ prior to H5N1infection, which is known to cause severe lung damage and respiratory disease. We found that PM₁₀ enhances vulnerability (by cellular damage) and regulates virus infectivity to enhance overall pathogenic burden in the lung cells. Additionally, the transcriptomic profile highlights the connection of host factors related to various metabolic pathways and immune responses which were dysregulated during virus infection. Collectively, our findings suggest a strong link between the prevalence of respiratory illness and its association with the air quality.
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