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Indoor air quality at life and work environments in Rome, Italy Texte intégral
2016
Romagnoli, P. | Balducci, C. | Perilli, M. | Vichi, F. | Imperiali, A. | Cecinato, A.
The air quality of three different microenvironments (school, dwelling, and coffee bar) located in the city of Rome, Italy, was assessed. Indoor and outdoor concentrations of polycyclic aromatic hydrocarbons (PAHs) associated with PM₂.₅ particles were determined during an intensive 3-week sampling campaign conducted in March 2013. In interiors, total particulate PAHs ranged from 1.53 to 4.96 ng/m³ while outdoor air contained from 2.75 to 3.48 ng/m³. In addition, gaseous toxicants, i.e., NO₂, NO ₓ , SO₂, O₃, and BTEX (benzene, toluene, ethyl-benzene, and xylene isomers), were determined both in internal and external air. To solve the origin of indoor and outdoor PAHs, several source apportionment methods were applied. Multivariate analysis revealed that emissions from motor vehicles, biomass burning for heating purposes, and soil resuspension were the major sources of PAHs in the city. No linear correlation was established between indoor and outdoor values for PM₂.₅ and BTEX; the respective indoor/outdoor concentration ratios exceed unity except for PM₂.₅ in the no smoking home and benzene in all school floors. This suggests that important internal sources such as tobacco smoking, cleaning products, and resuspension dust contributed to indoor pollution. Using the monitoring stations of ARPA Lazio regional network as reference, the percentage within PAH group of benzo[a]pyrene, which is the WHO marker for the carcinogenic risk estimates, was ca. 50 % higher in all locations investigated.
Afficher plus [+] Moins [-]Cytotoxicity and alterations at transcriptional level caused by metals on fish erythrocytes in vitro Texte intégral
2016
Morcillo, Patricia | Romero, Diego | Meseguer, José | Esteban, M Ángeles | Cuesta Arranz, Alberto
The in vitro use of fish erythrocytes to test the toxicity of aquatic pollutants could be a valuable alternative to fish bioassays but has received little attention. In this study, erythrocytes from marine gilthead sea bream (Sparus aurata L.) and European sea bass (Dicentrarchus labrax L.) specimens were exposed for 24 h to Cd, Hg, Pb and As and the resulting cytotoxicity was evaluated. Exposure to metals produced a dose-dependent reduction in the viability, and mercury showed the highest toxicity followed by MeHg, Cd, As and Pb. Moreover, fish erythrocytes incubated with each one of the metals exhibited alteration in gene expression profile of metallothionein, superoxide dismutase, catalase, peroxiredoxin, glutathione reductase, heat shock proteins 70 and 90, Bcl2-associated X protein and calpain1 indicating cellular protection, stress and apoptosis death as well as oxidative stress. This study points to the benefits for evaluating the toxicological mechanisms of marine pollution using fish erythrocytes in vitro.
Afficher plus [+] Moins [-]Dissipation and runoff transport of metazachlor herbicide in rapeseed cultivated and uncultivated plots in field conditions Texte intégral
2016
Mantzos, Nikolaos | Hela, Dimitra | Karakitsou, Anastasia | Antonopoulou, Maria | Konstantinou, Ioannis
The environmental fate of metazachlor herbicide was investigated under field conditions in rapeseed cultivated and uncultivated plots, over a period of 225 days. The cultivation was carried out in silty clay soil plots with two surface slopes, 1 and 5 %. The herbicide was detectable in soil up to 170 days after application (DAA), while the dissipation rate was best described by first-order kinetics and its half-life ranged between 10.92 and 12.68 days. The herbicide was detected in the soil layer of 10–20 cm from 5 to 48 DAA, and its vertical movement can be described by the continuous stirred tank reactor (CSTR) in series model. Relatively low amounts of metazachlor (less than 0.31 % of the initial applied active ingredient) were transferred by runoff water. More than 80 % of the total losses were transferred at the first runoff event (12 DAA), with herbicide concentrations in runoff water ranging between 70.14 and 79.67 μg L⁻¹. Minor amounts of the herbicide (less than 0.07 % of the initial applied active ingredient) were transferred by the sediment, with a maximum concentration of 0.57 μg g⁻¹ (12 DAA), in plots with 5 % inclination. Finally, in rapeseed plants, metazachlor was detected only in the first sampling (28 DAA) at concentrations slightly higher than the limit of quantification; when in seeds, no residues of the herbicide were detected.
Afficher plus [+] Moins [-]Solanum torvum Swartz. fruit attenuates cadmium-induced liver and kidney damage through modulation of oxidative stress and glycosylation Texte intégral
2016
Ramamurthy, C. H. | Subastri, A. | Suyavaran, A. | Subbaiah, K. C. V. | Valluru, L. | Tirunāvukkaracu, Ci.
Increased levels of environmental pollutants are linked to almost all human disorders; the efficient method to manage the human health is through naturally available dietary molecule. Solanum torvum (ST) Swartz (Solanaceae) commonly called Turkey Berry is found in Africa, Asia, and South America. Its fruit, part of traditional Indian cuisine, is a widely consumed nutritious herb, acclaimed for its medicinal value. ST aqueous extract (STAe) (250, 500, and 1000 mg/kg b.w., 6 days; oral) against acute Cadmium (Cd) (6.3 mg/kg b.w., single dose; oral) toxicity was evaluated in rats. Protective effect was assessed using serum markers, tissue antioxidants, oxidant derivatives, glycoprotein, and histopathological studies. The activities of serum marker enzymes were increased (40–60 %); antioxidant enzymes such as SOD and CAT, GSH, and its metabolic enzyme activities were decreased (50–80 %) in the liver and kidney upon Cd intoxication. During STAe pre-treatment, at doses of 250 and 500 mg/kg b.w., the above changes were brought to near normal (25–63 %). Tissue 4-hydroxynonenal, 3-nitrotyrosine, and protein carbonyls were increased (8–15 fold) in Cd-alone-treated rats, whereas pre-supplementation of STAe significantly decreased their levels and inhibited the protein glycosylation effectively. The pharmacological effect of STAe was confirmed by histopathological observations. Based on previous literature and present investigation, we conclude that ST may serve as a potential functional food against environmental contaminant such as heavy metal-induced oxidative stress.
Afficher plus [+] Moins [-]The effect of anaerobic–aerobic and feast–famine cultivation pattern on bacterial diversity during poly-β-hydroxybutyrate production from domestic sewage sludge Texte intégral
2016
Liu, Changli | Liu, Di | Qi, Yingjie | Zhang, Ying | Liu, Xi | Zhao, Min
The main objective of this work was to investigate the influence of different oxygen supply patterns on poly-β-hydroxybutyrate (PHB) yield and bacterial community diversity. The anaerobic–aerobic (A/O) sequencing batch reactors (SBR1) and feast–famine (F/F) SBR2 were used to cultivate activated sludge to produce PHB. The mixed microbial communities were collected and analyzed after 3 months cultivation. The PHB maximum yield was 64 wt% in SBR1 and 53 wt% in SBR2. Pyrosequencing analysis 16S rRNA gene of two microbial communities indicated there were nine and four bacterial phyla in SBR1 and SBR2, respectively. Specifically, Proteobacteria (36.4 % of the total bacterial community), Actinobacteria (19.7 %), Acidobacteria (14.1 %), Firmicutes (4.4 %), Bacteroidetes (1.7 %), Cyanobacteria/Chloroplast (1.5 %), TM7 (0.8 %), Gemmatimonadetes (0.2 %), and Nitrospirae (0.1 %) were present in SBR1. Proteobacteria (94.2 %), Bacteroidetes (2.9 %), Firmicutes (1.9 %), and Actinobacteria (0.7 %) were present in SBR2. Our results indicated the SBR1 fermentation system was more stable than that of SBR2 for PHB accumulation.
Afficher plus [+] Moins [-]‘End to end’ planktonic trophic web and its implications for the mussel farms in the Mar Piccolo of Taranto (Ionian Sea, Italy) Texte intégral
2016
Karuza, Ana | Caroppo, Carmela | Monti, Marina | Camatti, Elisa | Di Poi, Elena | Stabili, Loredana | Auriemma, Rocco | Pansera, Marco | Cibic, Tamara | Del Negro, Paola
The Mar Piccolo is a semi-enclosed basin subject to different natural and anthropogenic stressors. In order to better understand plankton dynamics and preferential carbon pathways within the planktonic trophic web, an integrated approach was adopted for the first time by examining all trophic levels (virioplankton, the heterotrophic and phototrophic fractions of pico-, nano- and microplankton, as well as mesozooplankton). Plankton abundance and biomass were investigated during four surveys in the period 2013–2014. Beside unveiling the dynamics of different plankton groups in the Mar Piccolo, the study revealed that high portion of the plankton carbon (C) pool was constituted by small-sized (<2 μm) planktonic fractions. The prevalence of small-sized species within micro- and mesozooplankton communities was observed as well. The succession of planktonic communities was clearly driven by the seasonality, i.e. by the nutrient availability and physical features of the water column. Our hypothesis is that beside the ‘bottom-up’ control and the grazing pressure, inferred from the C pools of different plankton groups, the presence of mussel farms in the Mar Piccolo exerts a profound impact on plankton communities, not only due to the important sequestration of the plankton biomass but also by strongly influencing its structure.
Afficher plus [+] Moins [-]Assessment of trace metal contamination in the sea cucumber (Holothuria tubulosa) and sediments from the Dardanelles Strait (Turkey) Texte intégral
2016
Turk Culha, Saniye | Dereli, Hakkı | Karaduman, Fatma Rabia | Culha, Mehmet
This study was performed to determine the concentrations of some trace metals (Cd, Cu, Pb, Ni, Zn, and Fe) in Holothuria tubuosa (Gmelin, 1788) belonging to Echinoderm species and in sediments that they live at three different stations (Gelibolu, Umur Bey/Lapseki, and Dardanos) on Dardanelles Strait between April 2013 and March 2014. The mean trace metal concentrations determined in H. tubulosa and sediment were as follows: Cd 0.18 mg/kg, Cu 2.43 mg/kg, Pb 2.09 mg/kg, Ni 14.58 mg/kg, Zn 16.86 mg/kg, and Fe 73.46 mg/kg and Cd 0.70 mg/kg, Cu 5.03 mg/kg, Pb 14.57 mg/kg, Ni 27.15 mg/kg, Zn 54.52 mg/kg, and Fe 3779.9 mg/kg, respectively. It was detected that the statistical difference between trace metals determined seasonally in muscle tissue of H. tubulosa was significant (p > 0.05). As a result of the study, it was detected that H. tubulosa is a bioindicator species in determining Ni trace metal in sediment. The results were compared to the limit values of National and International Food Safety, and it was detected that Cd and Ni concentrations measured in sediment were above LEL of Ni and Cd concentrations according to Sediment Quality Guidelines.
Afficher plus [+] Moins [-]Report on the fifth meeting of INRA’s national network of ecotoxicologists, ECOTOX Texte intégral
2016
Mougin, Christian | Bouchez, Agnès | Denaix, Laurence | Lamy, Isabelle | Laurent, François | Martin-Laurent, Fabrice | Mench, Michel
Report on the fifth meeting of INRA’s national network of ecotoxicologists, ECOTOX Texte intégral
2016
Mougin, Christian | Bouchez, Agnès | Denaix, Laurence | Lamy, Isabelle | Laurent, François | Martin-Laurent, Fabrice | Mench, Michel
The fifth meeting of INRA’s national network of ecotoxicologists took place on 25 to 27 November 2014 in Biarritz, France. The main aim of the meeting was to bring together ecotoxicologists from INRA and associated partners, providing them ample opportunity to share and discuss their latest scientific results as well as the national policy of research in ecotoxicology and to precise perspectives for the network.
Afficher plus [+] Moins [-]Report on the fifth meeting of INRA’s national network of ecotoxicologists, ECOTOX Texte intégral
2016
Mougin, Christian | Bouchez, Agnes | Denaix, Laurence | Lamy, Isabelle | Laurent, Francois | Martin-Laurent, Fabrice | Mench, Michel | Ecologie fonctionnelle et écotoxicologie des agroécosystèmes (ECOSYS) ; Institut National de la Recherche Agronomique (INRA)-AgroParisTech | Centre Alpin de Recherche sur les Réseaux Trophiques et Ecosystèmes Limniques (CARRTEL) ; Institut National de la Recherche Agronomique (INRA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry]) | Interactions Sol Plante Atmosphère (UMR ISPA) ; Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Supérieure des Sciences Agronomiques de Bordeaux-Aquitaine (Bordeaux Sciences Agro) | Métabolisme et Xénobiotiques (ToxAlim-MeX) ; ToxAlim (ToxAlim) ; Institut National de la Recherche Agronomique (INRA)-Université Toulouse III - Paul Sabatier (UT3) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Ecole Nationale Vétérinaire de Toulouse (ENVT) ; Institut National Polytechnique (Toulouse) (Toulouse INP) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National Polytechnique (Toulouse) (Toulouse INP) ; Université de Toulouse (UT)-Ecole d'Ingénieurs de Purpan (INP - PURPAN) ; Institut National Polytechnique (Toulouse) (Toulouse INP) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National de la Recherche Agronomique (INRA)-Université Toulouse III - Paul Sabatier (UT3) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Ecole Nationale Vétérinaire de Toulouse (ENVT) ; Institut National Polytechnique (Toulouse) (Toulouse INP) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National Polytechnique (Toulouse) (Toulouse INP) ; Université de Toulouse (UT)-Ecole d'Ingénieurs de Purpan (INP - PURPAN) ; Institut National Polytechnique (Toulouse) (Toulouse INP) ; Université de Toulouse (UT)-Université de Toulouse (UT) | Agroécologie [Dijon] ; Institut National de la Recherche Agronomique (INRA)-Université de Bourgogne (UB)-AgroSup Dijon - Institut National Supérieur des Sciences Agronomiques, de l'Alimentation et de l'Environnement | Biodiversité, Gènes & Communautés (BioGeCo) ; Institut National de la Recherche Agronomique (INRA)-Université de Bordeaux (UB) | ANR-11-LABX-0034,BASC,Biodiversité, Agroécosystèmes, Société, Climat(2011)
The fifth meeting of INRA’s national network of ecotoxicologists took place on 25 to 27 November 2014 in Biarritz, France. The main aim of the meeting was to bring together ecotoxicologists from INRA and associated partners, providing them ample opportunity to share and discuss their latest scientific results as well as the national policy of research in ecotoxicology and to precise perspectives for the network.
Afficher plus [+] Moins [-]GC-MS analysis of bioactive components and biosynthesis of silver nanoparticles using Hybanthus enneaspermus at room temperature evaluation of their stability and its larvicidal activity Texte intégral
2016
Suman, T. Y. | Rajasree, S. R Radhika | Jayaseelan, C. | Mary, R Regina | Gayathri, S. | Aranganathan, L. | Remya, R. R.
Green synthesis of silver nanoparticles (AgNPs) using Hybanthus enneaspermus extract at room temperature that act as a reducing agent as well as capping agent has been investigated. The synthesized AgNPs were characterized by UV–visible spectroscopy, X-ray diffraction (XRD), Fourier transform infrared (FTIR), zeta potential, and dynamic light scattering (DLS) transmission electron microscopy (TEM) and energy-dispersive X-ray (EDX). The silver surface plasmon resonance was observed at 420 nm in the UV–visible spectrum. XRD peaks were observed at 2θ values in 38.20°, 44.40°, 64.60°, and 77.50° which are indexed as (111), (200), (220), and (311) bands of face-centered cubic (fcc) structures of silver. FTIR revealed the AgNPs were capped with plant compounds of alcohol, phenols, carbonyl, amines, and amide functional groups. TEM image shows that the particles were of spherical, hexagonal, and triangular in shape, and the size range was 16–26 nm. Further, DLS exhibits the average size of 25.2 nm and the zeta values were measured (−27.1 mV) which proves the stability of the AgNPs. The conversion of Ag⁺ ions into Ag⁰ was calculated using inductively coupled plasma atomic emission spectroscopy (ICP-MS) and was found to be 96 %. The biosynthesized AgNPs showed the larvicidal activity with the LC₅₀ values of 17.24 and 13.12 mg/L against the fourth-instar larvae of Anopheles subpictus and Culex quinquefasciatus, respectively. The GC-MS analysis of the plant extract showed that 39 bioactive phytochemical compounds have been found to possess a wide range of activities, which may help in the protection against incurable diseases.
Afficher plus [+] Moins [-]Using air, soil and vegetation to assess the environmental behaviour of siloxanes Texte intégral
2016
Ratola, N. | Ramos, S. | Homem, V. | Silva, J. A. | Jiménez-Guerrero, P. | Amigo, J. M. | Santos, L. | Alves, A.
This study aimed to contribute to the enhancement of the knowledge of levels, trends and behaviour of eight siloxanes (four linear and four cyclic) in the environment. Adding to the prioritised scrutiny of the incidence in the atmosphere through passive samplers (sorbent-impregnated polyurethane foam disks—SIPs), the sampling of pine needles and soil was also performed, thus closing the circle of atmospheric exposure in the areas of study. Two sampling campaigns (one in summer and one in winter) were done in a total of eight sampling points in the Portuguese territory, which covered a wide range of human presence and land uses (urban, industrial, remote and beach areas). By adopting a “green” approach in terms of analytical methods, namely reducing the clean-up steps for the passive air samples and using the quick, easy, cheap, effective, rugged and safe (QuEChERS) technology for soils and pine needles, the results showed total concentration of siloxanes between 5 and 70 ng g⁻¹ (dry weight) for soils and from 2 to 118 ng g⁻¹ (dry weight (dw)) for pine needles, with no clear seasonal trend. For SIPs, the levels varied from 0.6 to 7.8 ng m⁻³ and were higher in summer than in winter in all sites. Overall, the cyclic siloxanes were found in much higher concentrations, with D5 and D6 being the most predominant in a great majority of cases. Also, the urban and industrial areas had the highest incidence, suggesting a strong anthropogenic fingerprint, in line with their main uses.
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