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COMT1 overexpression resulting in increased melatonin biosynthesis contributes to the alleviation of carbendazim phytotoxicity and residues in tomato plants Full text
2019
Yan, Yanyan | Sun, Shasha | Zhao, Ning | Yang, Wanying | Shi, Qinghua | Gong, Biao
Melatonin (Mel) serves as an important signalling molecule in various aspects of stress tolerance in plants. However, the function of Mel in pesticide metabolism remains unknown. Here, selecting the widely used fungicide carbendazim (MBC) as the model, we found that exogenous Mel had the ability to alleviate pesticide phytotoxicity and residues in tomato as well as in some other vegetables. Additionally, overexpression of the Mel biosynthetic gene caffeic acid O-methyltransferase 1 (COMT1) significantly enhanced the capacity of the tomato to reduce MBC phytotoxicity and residue. This outcome was mainly because of the Mel-induced antioxidant capability, as well as the key detoxification process. Indeed, levels of reactive oxygen species (ROS) and lipid peroxides significantly decreased after applying exogenous Mel or overexpressing COMT1, which resulted from direct ROS scavenging, and increased Mel levels significantly enhanced antioxidant enzymatic activity. More importantly, Mel activated the ascorbate-glutathione cycle to participate in glutathione S-transferase-mediated pesticide detoxification. A grafting experiment showed that rootstocks from COMT1 transgenic plants increased the Mel accumulation of wild-type scions, resulting in MBC metabolism in the scions. To our knowledge, this is the first report providing evidence of Mel-induced pesticide metabolism, which provides a novel approach for minimizing pesticide residues in crops by exploiting plant self-detoxification mechanisms.
Show more [+] Less [-]Variation of Feammox following ammonium fertilizer migration in a wheat-rice rotation area, Taihu Lake, China Full text
2019
Qin, Yunbin | Ding, Bangjing | Li, Zhengkui | Chen, Shi
Feammox is a newly discovered and important anaerobic nitrogen (N) loss pathway, and its variation and role in removing N following the application of N fertilizer and its migration from paddies to other land use types and from surface soils to deep soils have not been thoroughly elucidated to date. In this study, field sampling and slurry incubation experiments were performed to evaluate the Feammox rate between different land use types (paddy, irrigation ditch, riparian zone and lake, 0–10 cm) and different paddy soil depths (0–70 cm) in a wheat-rice rotation area in China. Based on a ¹⁵N-labelled isotope-tracing technique and analysis of microbial communities, it was estimated that the potential Feammox rate ranged from 0.031 to 0.42 mg N kg⁻¹ d⁻¹ in this area. In the soil profile of the paddy, the depth of 20–30 cm was the active region of Feammox, with a value of 0.37 ± 0.057 mg N kg⁻¹ d⁻¹. Compared with the surface soil (0–10 cm) of the paddy (0.18 ± 0.031 mg N kg⁻¹ d⁻¹), the potential Feammox rate of the irrigation ditch soil was not significantly different, but that of the lake riparian soil and lake sediment were decreased by 27.27% and 32.11%, respectively (p < 0.01). Fe(III) content was the best predictor of the Feammox rate and explained the variation of the Feammox rate by 36.00% in the surface soil. At the genus level, the paddy soil at a depth of 20–30 cm had the greatest abundance of the genera in which the Fe reduction bacteria were distributed; and where Bacillus, Geobacter and Anaeromyxobacter had higher proportions. It was estimated that the potential N loss by Feammox was in the range of 7.36 (the lake) ∼43.35 (the paddy) kg N ha⁻¹ year⁻¹ in the surface soil of this area. Considering denitrification and the Feammox rate as a whole, we found that denitrification remained to be the main contributor to N loss in the surface soil (94.72–96.89% of N loss), although Feammox dominated N loss in the deep soil (below 0–10 cm).
Show more [+] Less [-]Urban vegetation loss and ecosystem services: The influence on climate regulation and noise and air pollution Full text
2019
De Carvalho, Roberta Mendonça | Szlafsztein, Claudio Fabian
Ecosystem services are present everywhere, green vegetation coverage (or green areas) is one of the primary sources of ecosystem services considering urban areas sustainability and peoples urban life quality. Urban vegetation cover loss decreases the capacity of nature to provision ecosystem services; the loss of urban vegetation is also observed within the Amazon. This study aims at identifying urban vegetation loss and relate it to the provision of ecosystem services of reduction of air quality, reduction of air pollution, and climate regulation. Urban vegetation coverage loss was calculated using NDVI on LANDSAT 5 imagery over a 23-year period from 1986 to 2009. NDVI thresholds were arbitrarily selected, and complemented by in locus observation, to establish guidelines for quantitative (area) and qualitative (density) evolution of green cover, divided in six different categories, named as water, bare soil, poor vegetation, moderate vegetation, dense vegetation and very dense vegetation. Data on air pollution, noise pollution and temperature were outsourced from previous works. Measurement show a significant loss of very dense, dense and moderate vegetation coverage and an increase in poor vegetation and bare soil areas, in accordance to increase in air and noise pollution, and local temperature, and provides positive refashions between the loss of urban green coverage and decrease in ecosystem services.
Show more [+] Less [-]Sorption and transport of aluminum dialkyl phosphinate flame retardants and their hydrolysates in soils Full text
2019
Shi, Fengqiong | Hao, Zhineng | Liang, Yong | Liu, Jiyan | Liu, Jingfu
Aluminum dialkyl phosphinates (ADPs) are a class of promising phosphorus-containing flame retardants, but their environmental fate is not well understood. Sorption and transport behaviors of ADPs, and their hydrolysates dialkyl phosphinic acids (DPAs) were studied by batch and column experiments. ADPs are less mobile in soil columns with more than half (>52.6%) of ADPs retained in the soil and residues in the topmost 2-cm layer account for more than 57% of total residues. Dissolution and dispersion of fine grain ADPs were responsible for the transport of ADPs. Sorption DPAs (logKₒc) was significantly related to the lipophilicity of DPAs (logD) (p < 0.05). Soil pH and clay content were the dominant factors governing the sorption and transport of DPAs in soils, indicating the importance of electrostatic interactions. The retardation factors (R) of DPAs derived from leaching experiments were pH-dependent with larger R values in the acidic soil (pH = 4.0) where anionic and neutral species of DPAs coexisted. Both physical and chemical non-equilibrium convection-dispersion equations (CDE) yield appropriate modeling for DPAs transport. In most cases, R values estimated from column tests differed from those derived from the batch experiments, which might be attributed to non-equilibrium sorption processes in dynamic conditions.
Show more [+] Less [-]Short-term exposure to ambient ozone and inflammatory biomarkers in cross-sectional studies of children and adolescents: Results of the GINIplus and LISA birth cohorts Full text
2019
Zhao, Tianyu | Markevych, Iana | Standl, Marie | Schikowski, Tamara | Berdel, Dietrich | Koletzko, Sibylle | Jörres, Rudolf A. | Nowak, Dennis | Heinrich, Joachim
While exposure to ambient particulate matter (PM) and nitrogen dioxide (NO₂) is thought to be associated with diseases via inflammatory response, the association between exposure to ozone, an oxidative pollutant, and inflammation has been less investigated.We analyzed associations between short-term exposure to ozone and three inflammatory biomarkers among children and adolescents.These cross-sectional analyses were based on two follow-ups of the GINIplus and LISA German birth cohorts. We included 1330 10-year-old and 1591 15-year-old participants. Fractional exhaled nitric oxide (FeNO) and high-sensitivity C-reactive protein (hs-CRP) were available for both age groups while interleukin (IL)-6 was measured at 10 years only. Maximum 8-h averages of ozone and daily average concentrations of NO₂ and PM with an aerodynamic diameter <10 μm (PM₁₀) were adopted from two background monitoring stations 0 (same day), 1, 2, 3, 5, 7, 10 and 14 days prior to the FeNO measurement or blood sampling. To assess associations, we utilized linear regression models for FeNO, and logistic regressions for IL-6 and hs-CRP, adjusting for potential covariates and co-pollutants NO₂ and PM₁₀.We found that short-term ozone exposure was robustly associated with higher FeNO in adolescents at age 15, but not at age 10. No consistent associations were observed between ozone and IL-6 in children aged 10 years. The relationship between hs-CRP levels and ozone was J-shaped. Relatively low ozone concentrations (e.g., <120 μg/m³) were associated with reduced hs-CRP levels, while high concentrations (e.g., ≥120 μg/m³) tended to be associated with elevated levels for both 10- and 15-year-old participants.Our study demonstrates significant associations between short-term ozone exposure and FeNO at 15 years of age and a J-shaped relationship between ozone and hs-CRP. The finding indicates that high ozone exposure may favor inflammatory responses in adolescents, especially regarding airway inflammation.
Show more [+] Less [-]Bisphenols (A, S, and F) affect the basic hormonal activity determined for pharmaceuticals – Study of Saccharomyces cerevisiae Full text
2019
Kudłak, Błażej | Wieczerzak, Monika | Namieśnik, Jacek
Pharmaceuticals and analogs of bisphenol A (BPA) are increasingly threatening environmental pollutants. In this study, mixtures of selected pharmaceuticals (diclofenac sodium salt, chloramphenicol, oxytetracycline hydrochloride, fluoxetine hydrochloride, estrone, ketoprofen, progesterone, gemfibrozil and androstenedione) were prepared with BPA and its two analogs (namely, bisphenols F and S) at such ratios to reflect environmentally detectable levels. Then, the mixture solutions were studied with a XenoScreen YES/YAS assay to determine the variations in the initial hormonal response of each pharmaceutical compound due to the presence of a bisphenol analog. The results obtained were modeled with the concentration addition (CA) and independent action (IA) approaches, the trueness of which was studied with model deviation ratios (MDR). The estrogenic agonistic activity of the drugs studied was most strongly affected by the presence of BPA in solution (twenty-one cases of synergy observed for CA models versus twelve cases of antagonism in the case of IA predictions). BPS shows a strong agonistic estrogenic impact on most of the drugs studied at medium and high concentration levels; androgenic agonistic activity was also impaired with elevated concentrations of BPS. Increasing the concentration of BPF in a reaction mixture also increased the number of YES + synergism incidences (for CA modeling). Estrone, progesterone and androstenedione were mostly affected by the highest BPF concentrations studied in the case of androgenic agonistic research performed.
Show more [+] Less [-]Commentary: EPA's proposed expansion of dose-response analysis is a positive step towards improving its ecological risk assessment Full text
2019
Agathokleous, Evgenios | Anav, Alessandro | Araminiene, Valda | De Marco, Alessandra | Domingos, Marisa | Kitao, Mitsutoshi | Koike, Takayoshi | Manning, William J. | Paoletti, Elena | Saitanis, Costas J. | Sicard, Pierre | Vitale, Marcello | Wang, Wenjie | Calabrese, Edward J.
The United States Environmental Protection Agency (US EPA) has recently proposed changes to strengthen the transparency of its pivotal regulatory science policy and procedures. In this context, the US EPA aims to enhance the transparency of dose-response data and models, proposing to consider for the first time non-linear biphasic dose-response models. While the proposed changes have the potential to lead to markedly improved ecological risk assessment compared to past and current approaches, we believe there remain open issues for improving the quality of ecological risk assessment, such as the consideration of adaptive, dynamic and interactive effects. Improved risk assessment including adaptive and dynamic non-linear models (beyond classic threshold models) can enhance the quality of regulatory decisions and the protection of ecological health. We suggest that other countries consider adopting a similar scientific-regulatory posture with respect to dose-response modeling via the inclusion of non-linear biphasic models, that incorporate the dynamic potential of biological systems to adapt (i.e., enhancing positive biological endpoints) or maladapt to low levels of stressor agents.
Show more [+] Less [-]Clock-Bmal1 mediates MMP9 induction in acrolein-promoted atherosclerosis associated with gut microbiota regulation Full text
2019
Wu, Xiaoyue | Chen, Lijun | Zeb, Falak | Li, Chaofeng | Jiang, Pan | Chen, Aochang | Xu, Chuyue | Haq, Ijaz ul | Feng, Qing
Circadian rhythm is believed to play important roles in atherosclerosis. The gut microbiota is found to be closely related to atherogenesis, and shows compositional and functional circadian oscillation. However, it's still unclarified whether circadian clock and intestinal microbiota are involved in the progression of atherosclerosis induced by environmental pollutant acrolein. Herein, patients with atherosclerosis showed higher MMP9, a promising biomarker for atherosclerosis, and lower Bmal1 and Clock expression in the plasma. Interestingly, acrolein exposure contributed to the increased MMP9, decreased Clock and Bmal1, and activated MAPK pathways in human umbilical vein endothelial cells (HUVECs). We found that knockdown of Clock or Bmal1 lead to upregulation of MMP9 in HUVECs, and that Clock and Bmal1 expression was elevated while MAPK pathways were blocked. Atherosclerotic apolipoproteinE-deficient mice consumed a high-fat diet were used and treated with acrolein (3 mg/kg/day) in the drinking water for 12 weeks. Upregulation of MMP9, and downregulation of Clock and Bmal1 were also observed in plasma of the mice. Besides, acrolein feeding altered gut microbiota composition at a phylum level especially for an increased Firmicutes and a decreased Bacteroidetes. Additionally, gut microbiota showed correlation with atherosclerotic plaque, MMP9 and Bmal1 levels. Therefore, our findings indicated that acrolein increased the expression of MMP9 through MAPK regulating circadian clock, which was associated with gut microbiota regulation in atherosclerosis. Circadian rhythms and gut microbiota might be promising targets in the prevention of cardiovascular disease caused by environmental pollutants.
Show more [+] Less [-]Efficient degradation of AO7 by ceria-delafossite nanocomposite with non-inert support as a synergistic catalyst in electro-fenton process Full text
2019
Nazari, Pegah | Tootoonchian, Pedram | Setayesh, Shahrbanoo Rahman
CuFeO₂/CeO₂ as a novel catalyst was synthesized and its catalytic performance was evaluated for electro-Fenton degradation of acid orange 7 (AO7). It was demonstrated from the characterization results that the rhombohedral structure of CuFeO₂ and face-centered cubic fluorite structure of CeO₂ remained stable after nanocomposite construction. The impact of such operating parameters as pH, current intensity and, catalyst amount was investigated and the optimum conditions (100 mgL⁻¹ AO7, pH 3, 150 mgL⁻¹ CuFeO₂/CeO₂, I: 150 mA) determination led to 99.3% AO7 removal and 79.1% COD removal in 60 min. The introduction of CeO₂ as non-inert support had a significant impact on H₂O₂ electro-generation as an important step in AO7 removal. CuFeO₂/CeO₂ presented negligible metal leaching (iron 4.13%, copper 2.4%, and cerium 0.33%) which could be due to the strong interaction between active species and support. The nanocomposite performed efficiently in salty systems and two samples of real wastewaters due to Brønsted acidity character of ceria, which makes it a potential choice in industrial applications. The good performance of nanocomposite could be the result of the synergistic effect between Fe, Cu, and Ce. Regarding scavenging measurements results, the electro-Fenton process followed the Haber-Weiss mechanism. The by-products detection was performed using GC-MS analysis to propose an acceptable pathway for EF degradation of AO7. The BMG kinetics model (1/b = 0.969 (min) and 1/m = 0.269 (min⁻¹)) was matched with the experimental data and described the kinetics of reaction very well. The catalytic activity of CuFeO₂/CeO₂ almost remained after six cycles. Based on the obtained results, CuFeO₂/CeO₂ using the benefit of the synergistic effect of Ce³⁺ with Fe²⁺ and Cu⁺can be introduced as a promising novel catalyst for the electro-Fenton reaction in wastewater treatment.
Show more [+] Less [-]Residues of pesticides and some metabolites in dissolved and particulate phase in surface stream water of Cachapoal River basin, central Chile Full text
2019
Climent, María José | Herrero-Hernández, Eliseo | Sánchez-Martín, M. Jesús (María Jesús) | Rodríguez-Cruz, M. Sonia (María Sonia) | Pedreros, Pablo | Urrutia, Roberto
Residues of pesticides and some metabolites in dissolved and particulate phase in surface stream water of Cachapoal River basin, central Chile Full text
2019
Climent, María José | Herrero-Hernández, Eliseo | Sánchez-Martín, M. Jesús (María Jesús) | Rodríguez-Cruz, M. Sonia (María Sonia) | Pedreros, Pablo | Urrutia, Roberto
In the last twenty years, pesticide use in Chile has increased more than 160%, generating a greater risk of water resources pollution. The objective of this study was to assess the presence of 22 pesticides and 12 degradation products in surface water samples from the Cachapoal River basin, Central Chile, an area characterized by intense agricultural activity. Pesticide concentrations in the dissolved phase (DP) and particulate phase (PP) in samples collected in the dry season and after precipitation events was assessed. The solid-phase extraction technique was used to preconcentrate the samples and GC/MS and LC/MS were used to detect pesticides. The results present spatio-temporal variations in the proportion and concentration of pesticides and their degradation products in both the DP and PP for each site and sampling period. The most ubiquitous compounds in the dissolved phase were atrazine, atrazine-2-hydroxy (HA), cyprodinil, pyrimethanil, and tebuconazole, while in the particulate phase HA, imidacloprid, diazinon and pyrimidinol were detected. The results presented in this study make up the first record of pesticides in the dissolved and particulate phases in surface water in Chile. They show that the problem of pesticide contamination undoubtedly affects the quality of bodies of water in agricultural areas in Chile and support the need for a proper assessment of the water quality of the Cachapoal River in the future.
Show more [+] Less [-]Residues of pesticides and some metabolites in dissolved and particulate phase in surface stream water of Cachapoal River basin, central Chile Full text
2019
Climent, Mar?a Jos? | Herrero Hern?ndez, Eliseo | S?nchez-Mart?n, Mar?a Jes?s | Rodr?guez-Cruz, Mar?a Sonia | Pedreros, Pablo | Urrutia, Roberto
[EN] In the last twenty years, pesticide use in Chile has increased more than 160%, generating a greater risk of water resources pollution. The objective of this study was to assess the presence of 22 pesticides and 12 degradation products in surface water samples from the Cachapoal River basin, Central Chile, an area characterized by intense agricultural activity. Pesticide concentrations in the dissolved phase (DP) and particulate phase (PP) in samples collected in the dry season and after precipitation events was assessed. The solid-phase extraction technique was used to preconcentrate the samples and GC/MS and LC/MS were used to detect pesticides. The results present spatio-temporal variations in the proportion and concentration of pesticides and their degradation products in both the DP and PP for each site and sampling period. The most ubiquitous compounds in the dissolved phase were atrazine, atrazine-2-hydroxy (HA), cyprodinil, pyrimethanil, and tebuconazole, while in the particulate phase HA, imidacloprid, diazinon and pyrimidinol were detected. The results presented in this study make up the first record of pesticides in the dissolved and particulate phases in surface water in Chile. They show that the problem of pesticide contamination undoubtedly affects the quality of bodies of water in agricultural areas in Chile and support the need for a proper assessment of the water quality of the Cachapoal River in the future.
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