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The comet assay in higher terrestrial plant model: Review and evolutionary trends Texto completo
2015
Lanier, Caroline | Manier, Nicolas | Cuny, Damien | Deram, Annabelle
The comet assay is a sensitive technique for the measurement of DNA damage in individual cells. Although it has been primarily applied to animal cells, its adaptation to higher plant tissues significantly extends the utility of plants for environmental genotoxicity research. The present review focuses on 101 key publications and discusses protocols and evolutionary trends specific to higher plants. General consensus validates the use of the percentage of DNA found in the tail, the alkaline version of the test and root study. The comet protocol has proved its effectiveness and its adaptability for cultivated plant models. Its transposition in wild plants thus appears as a logical evolution. However, certain aspects of the protocol can be improved, namely through the systematic use of positive controls and increasing the number of nuclei read. These optimizations will permit the increase in the performance of this test, namely when interpreting mechanistic and physiological phenomena.
Mostrar más [+] Menos [-]Eco-toxicity and human estrogenic exposure risks from OH-initiated photochemical transformation of four phthalates in water: A computational study Texto completo
2015
Gao, Yanpeng | An, Taicheng | Ji, Yuemeng | Li, Guiying | Zhao, Cunyuan
Transformation products (TPs) of emerging organic contaminates (EOCs) in water are still rarely considered in environmental risk assessment, although some have been found to be concern. OH is believed as an important reactive species both in indirect phototransformation and advanced oxidation technology. Thus, eco-toxicity and human estrogenic exposure risks of four phthalates and TPs during the OH-initiated photochemical process were investigated using computational approach. Four phthalates can be degraded through OH-addition and H-transfer pathways. The OH-addition TPs were predominant for dimethyl phthalates, while H-transfer TPs were predominant for other three phthalates. Compared with phthalates, OH-addition TPs (o-OH-phthalates) were one level more toxic to aquatic organisms, and m-OH-phthalates exhibit higher estrogenic activity. Although H-transfer TPs were less harmful than OH-addition TPs, some of them still have aquatic toxicity and estrogenic activity. Therefore, more attentions should be paid to photochemical TPs and original EOCs, particularly those exhibiting high estrogenic activity to humans.
Mostrar más [+] Menos [-]Variations in phthalate ester (PAE) accumulation and their formation mechanism in Chinese flowering cabbage (Brassica parachinensis L.) cultivars grown on PAE-contaminated soils Texto completo
2015
Zhao, Hai-Ming | Du, Huan | Xiang, Lei | Chen, Yi-Liang | Lu, Lei-An | Li, Yan-Wen | Li, Hui | Cai, Quan-Ying | Mo, Ce-Hui
Phthalate ester (PAE) accumulation in crops poses great risks to human health and has aroused great concern. Here, we investigated variations in di-n-butylphthalate (DBP) and di-(2-ethylhexyl) phthalate (DEHP) accumulation by various Chinese flowering cabbage cultivars and revealed their variation mechanism. There were significant differences (p < 0.05) in shoot PAE concentrations of 28 cultivars. Moreover, significant positive correlations between DBP and DEHP concentrations in shoots of all cultivars indicated that they could be taken up simultaneously by various cultivars. Due to the lower translocation factor of low-PAE accumulator, its shoot PAEs concentrations were much lower than root compared to high-PAE accumulator. Further, subcellular distribution showed that PAE concentrations of root cell walls and organelles were much higher than those of shoots in low-PAE accumulator. Therefore, lower translocation from root to shoot and more PAEs accumulating in cell walls and organelles of root might act as main formation mechanism of low-PAE accumulator.
Mostrar más [+] Menos [-]Investigating social inequalities in exposure to drinking water contaminants in rural areas Texto completo
2015
Delpla, Ianis | Benmarhnia, Tarik | Lebel, Alexandre | Levallois, Patrick | Rodriguez, Manuel J.
Few studies have assessed social inequalities in exposure to drinking water contaminants. This study explores this issue in 593 rural municipalities of Québec, Canada. Quartiles of an ecological composite deprivation index were used as a proxy of socioeconomic status. Total trihalomethanes (TTHMs) and lead were chosen as proxies of chemical drinking water quality. The results show that the majority of deprived rural municipalities apply no treatment to their water (26%) or use a basic treatment (51%), whereas a relative majority of the wealthiest municipalities (40%) use advanced treatment. The proportion of municipalities having important lead (>5 μg/L) levels is highest in most deprived municipalities. Moreover, most deprived municipalities have a higher risk of high tap lead levels (RR = 1.33; 95%CI: 1.30, 1.36). Conversely, most deprived municipalities have a lower risk of high TTHMs levels (RR = 0.78; 95%CI: 0.69, 0.86). These findings suggest an environmental inequality in drinking water contaminants distribution in rural municipalities.
Mostrar más [+] Menos [-]Ozone effects on wheat grain quality – A summary Texto completo
2015
Broberg, Malin C. | Feng, Zhaozhong | Xin, Yue | Pleijel, Håkan
We synthesized the effects of ozone on wheat quality based on 42 experiments performed in Asia, Europe and North America. Data were analysed using meta-analysis and by deriving response functions between observed effects and daytime ozone concentration. There was a strong negative effect on 1000-grain weight and weaker but significant negative effects on starch concentration and volume weight. For protein and several nutritionally important minerals (K, Mg, Ca, P, Zn, Mn, Cu) concentration was significantly increased, but yields were significantly decreased by ozone. For other minerals (Fe, S, Na) effects were not significant or results inconclusive. The concentration and yield of potentially toxic Cd were negatively affected by ozone. Some baking properties (Zeleny value, Hagberg falling number) were positively influenced by ozone. Effects were similar in different exposure systems and for spring and winter wheat. Ozone effects on quality should be considered in future assessments of food security/safety.
Mostrar más [+] Menos [-]Modeling global distribution of agricultural insecticides in surface waters Texto completo
2015
Ippolito, Alessio | Kattwinkel, Mira | Rasmussen, Jes J. | Schäfer, Ralf B. | Fornaroli, Riccardo | Liess, Matthias
Agricultural insecticides constitute a major driver of animal biodiversity loss in freshwater ecosystems. However, the global extent of their effects and the spatial extent of exposure remain largely unknown. We applied a spatially explicit model to estimate the potential for agricultural insecticide runoff into streams. Water bodies within 40% of the global land surface were at risk of insecticide runoff. We separated the influence of natural factors and variables under human control determining insecticide runoff. In the northern hemisphere, insecticide runoff presented a latitudinal gradient mainly driven by insecticide application rate; in the southern hemisphere, a combination of daily rainfall intensity, terrain slope, agricultural intensity and insecticide application rate determined the process. The model predicted the upper limit of observed insecticide exposure measured in water bodies (n = 82) in five different countries reasonably well. The study provides a global map of hotspots for insecticide contamination guiding future freshwater management and conservation efforts.
Mostrar más [+] Menos [-]Predicting exposure of wildlife in radionuclide contaminated wetland ecosystems Texto completo
2015
Stark, K. | Andersson, P. | Beresford, N.A. | Yankovich, T.L. | Wood, M.D. | Johansen, M.P. | Vives i Batlle, J. | Twining, J. | Keum, D.-K. | Bollhöfer, A. | Doering, C. | Ryan, B. | Grzechnik, M. | Vandenhove, H.
Many wetlands support high biodiversity and are protected sites, but some are contaminated with radionuclides from routine or accidental releases from nuclear facilities. This radiation exposure needs to be assessed to demonstrate radiological protection of the environment. Existing biota dose models cover generic terrestrial, freshwater, and marine ecosystems, not wetlands specifically. This paper, which was produced under IAEA's Environmental Modelling for Radiation Safety (EMRAS) II programme, describes an evaluation of how models can be applied to radionuclide contaminated wetlands. Participants used combinations of aquatic and terrestrial model parameters to assess exposure. Results show the importance of occupancy factor and food source (aquatic or terrestrial) included. The influence of soil saturation conditions on external dose rates is also apparent. In general, terrestrial parameters provided acceptable predictions for wetland organisms. However, occasionally predictions varied by three orders of magnitude between assessors. Possible further developments for biota dose models and research needs are identified.
Mostrar más [+] Menos [-]Aerosol deposition doses in the human respiratory tree of electronic cigarette smokers Texto completo
2015
Manigrasso, Maurizio | Buonanno, Giorgio | Fuoco, Fernanda Carmen | Stabile, Luca | Avino, Pasquale
Aerosols from eight e-cigarettes at different nicotine levels and flavoring were characterized as particle number size distributions in the range 5.6–560 nm by FMPS and CPC. Results were used to provide dosimetry estimates applying the MMPD model.Particle number concentrations varied between 3.26 × 109 and 4.09 × 109 part cm−3 for e-liquids without nicotine and between 5.08 × 109 and 5.29 × 109 part cm−3 for e-liquids with nicotine. No flavor effects were detected on particle concentration data. Particle size distributions were unimodal with modes between 107–165 nm and 165–255 nm, for number and volume metrics, respectively.Averagely, 6.25 × 1010 particles were deposited in respiratory tree after a single puff. Highest deposition densities and mean layer thickness of e-cigarette liquid on the lung epithelium were estimated at lobar bronchi.Our study shows that e-cigarette aerosol is source of high particle dose in respiratory system, from 23% to 35% of the daily dose of a no-smoking individual.
Mostrar más [+] Menos [-]Ambient air pollution, temperature and out-of-hospital coronary deaths in Shanghai, China Texto completo
2015
Dai, Jinping | Chen, Renjie | Meng, Xia | Yang, Changyuan | Zhao, Zhuohui | Kan, Haidong
Few studies have evaluated the effects of ambient air pollution and temperature in triggering out-of-hospital coronary deaths (OHCDs) in China. We evaluated the associations of air pollution and temperature with daily OHCDs in Shanghai, China from 2006 to 2011. We applied an over-dispersed generalized additive model and a distributed lag nonlinear model to analyze the effects of air pollution and temperature, respectively. A 10 μg/m3 increase in the present-day PM10, PM2.5, SO2, NO2 and CO were associated with increases in OHCD mortality of 0.49%, 0.68%, 0.88%, 1.60% and 0.08%, respectively. A 1 °C decrease below the minimum-mortality temperature corresponded to a 3.81% increase in OHCD mortality on lags days 0–21, and a 1 °C increase above minimum-mortality temperature corresponded to a 4.61% increase over lag days 0–3. No effects were found for in-hospital coronary deaths. This analysis suggests that air pollution, low temperature and high temperature may increase the risk of OHCDs.
Mostrar más [+] Menos [-]Effect of pyoverdine supply on cadmium and nickel complexation and phytoavailability in hydroponics Texto completo
2015
Ferret, C. | Cornu, J. | Elhabiri, M. | Sterckeman, Thibault | Braud, A. | Jezequel, K. | Lollier, M. | Lebeau, T. | Schalk, I. | Geoffroy, V. | Service d'Hépato-gastro-entérologie et Nutrition [CHU Dupuytren 1, Limoges] ; CHU Limoges-Hôpital Dupuytren [CHU Limoges] | Laboratoire de chimie moléculaire (LCM) ; Université de Strasbourg (UNISTRA)-Institut de Chimie - CNRS Chimie (INC-CNRS)-Centre National de la Recherche Scientifique (CNRS) | Laboratoire Sols et Environnement (LSE) ; Institut National de la Recherche Agronomique (INRA)-Université de Lorraine (UL) | Laboratoire de Planétologie et Géodynamique [UMR 6112] (LPG) ; Université d'Angers (UA)-Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST) ; Université de Nantes (UN)-Université de Nantes (UN)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS) | Laboratoire Vigne Biotechnologie et Environnement (LVBE) ; Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA)) | Equipe Dépollution Biologique des Sols ; Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))
Effect of pyoverdine supply on cadmium and nickel complexation and phytoavailability in hydroponics Texto completo
2015
Ferret, C. | Cornu, J. | Elhabiri, M. | Sterckeman, Thibault | Braud, A. | Jezequel, K. | Lollier, M. | Lebeau, T. | Schalk, I. | Geoffroy, V. | Service d'Hépato-gastro-entérologie et Nutrition [CHU Dupuytren 1, Limoges] ; CHU Limoges-Hôpital Dupuytren [CHU Limoges] | Laboratoire de chimie moléculaire (LCM) ; Université de Strasbourg (UNISTRA)-Institut de Chimie - CNRS Chimie (INC-CNRS)-Centre National de la Recherche Scientifique (CNRS) | Laboratoire Sols et Environnement (LSE) ; Institut National de la Recherche Agronomique (INRA)-Université de Lorraine (UL) | Laboratoire de Planétologie et Géodynamique [UMR 6112] (LPG) ; Université d'Angers (UA)-Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST) ; Université de Nantes (UN)-Université de Nantes (UN)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS) | Laboratoire Vigne Biotechnologie et Environnement (LVBE) ; Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA)) | Equipe Dépollution Biologique des Sols ; Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))
International audience | Siderophores are chelators with a high selectivity for Fe(III) and a good affinity for divalent metals, including Cd(II) and Ni(II). Inoculation with siderophore-producing bacteria (SPB) has thus been proposed as an alternative to chelator supply in phytoremediation. Accurate assessments of the potential of this association require a dissection of the interaction of siderophores with metals at the soil–root interface. This study focuses on pyoverdine (Pvd), the main siderophore produced by Pseudomonas aeruginosa. We first assessed the ability of Pvd to coordinate Ni(II). The stability constant of Pvd–Ni(II) (log K L′Ni = 10.9) was found to be higher than that of Pvd–Cd(II) (log K L′Cd = 8.2). We then investigated the effect of a direct supply of Pvd on the mobilization, speciation, and phytoavailability of Cd and Ni in hydroponics. When supplied at a concentration of 50 μM, Pvd selectively promoted Ni mobilization from smectite. It decreased plant Ni and Cd contents and the free ionic fractions of these two metals, consistent with the free ion activity model. Pvd had a more pronounced effect for Ni than for Cd, as predicted from its coordination properties. Inoculation with P. aeruginosa had a similar effect on Ni phytoavailability to the direct supply of Pvd.
Mostrar más [+] Menos [-]Effect of pyoverdine supply on cadmium and nickel complexation and phytoavailability in hydroponics Texto completo
2015
Ferret, C. | Cornu, J. Y. | Elhabiri, M. | Sterckeman, T. | Braud, A. | Jezequel, K. | Lollier, M. | Lebeau, T. | Schalk, I. J. | Geoffroy, V. A.
Siderophores are chelators with a high selectivity for Fe(III) and a good affinity for divalent metals, including Cd(II) and Ni(II). Inoculation with siderophore-producing bacteria (SPB) has thus been proposed as an alternative to chelator supply in phytoremediation. Accurate assessments of the potential of this association require a dissection of the interaction of siderophores with metals at the soil–root interface. This study focuses on pyoverdine (Pvd), the main siderophore produced by Pseudomonas aeruginosa. We first assessed the ability of Pvd to coordinate Ni(II). The stability constant of Pvd–Ni(II) (log K ᴸ′ᴺⁱ = 10.9) was found to be higher than that of Pvd–Cd(II) (log K ᴸ′Cᵈ = 8.2). We then investigated the effect of a direct supply of Pvd on the mobilization, speciation, and phytoavailability of Cd and Ni in hydroponics. When supplied at a concentration of 50 μM, Pvd selectively promoted Ni mobilization from smectite. It decreased plant Ni and Cd contents and the free ionic fractions of these two metals, consistent with the free ion activity model. Pvd had a more pronounced effect for Ni than for Cd, as predicted from its coordination properties. Inoculation with P. aeruginosa had a similar effect on Ni phytoavailability to the direct supply of Pvd.
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