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Atmospheric Factors Affecting a Decrease in the Night-Time Concentrations of Tropospheric Ozone in a Low-Polluted Urban Area Full text
2018
Warmiński, Kazimierz | Bęś, Agnieszka
Ozone (O₃) decomposition in the troposphere is a very important process which prevents excessive O₃ accumulation in the air. It is particularly significant on warm summer days which are marked by a high risk of photochemical smog. We used Spearman’s rank correlation test to determine relationships between the drop in O₃ concentrations over time (-ΔO₃), nitrogen oxide (NO), nitrogen dioxide (NO₂), and total nitrogen oxide (NOₓ) concentrations and meteorological factors (1-h average) in low-polluted urban area in Olsztyn (north-eastern Poland). Nitrogen oxide concentrations were measured continuously by the chemiluminescence method, and O₃ concentrations were determined by the UV photometric method. The obtained results suggest that the rate of decomposition of tropospheric O₃ is affected mostly by the presence of NOₓ, high temperature, and air humidity (positive correlation) as well as by wind speed (negative correlation). Maximum correlation coefficient values were reported between –ΔO₃ and air temperature, –ΔO₃ and absolute air humidity when NOₓ concentrations were low (below 1.0 microgram per cubic meter), reaching 0.271 and 0.243, respectively. These results indicate that O₃ also reacted with air components other than NO and NO₂. Precipitation at average temperature of < 0 °C did not significantly contribute to a drop in O₃ concentrations at night-time. In the warm season, precipitation slowed down the rate of O₃ decomposition, mostly because NOₓ were scrubbed by rain. An analysis of seasonal and daily –ΔO₃ fluctuations revealed that –ΔO₃ values were highest in the summer and shortly after sunset in the diurnal cycle.
Show more [+] Less [-]The effects of colostrum on some biochemical parameters in the experimental intoxication of rats with paracetamol Full text
2018
Karabacak, Mürsel | Kanbur, Murat | Eraslan, Gökhan | Siliğ, Yavuz | Soyer Sarıca, Zeynep | Tekeli, Muhammet Yasin | Taş, Ayça
In the current study, the possible prophylactic and therapeutic effects of colostrum (COL) on acute organ injury caused by paracetamol (PAR) in rats were evaluated. Within the scope of this study, a 2-month-old male (150–200 g) 70 Wistar Albino rat was used and a total of seven groups were designed. The first group (CNT) was maintained for control purposes. The second group (COL-1) was given COL for 1 day, at a dose of 500 mg/kg at 6-h intervals, and blood and tissue sampling was performed at 24 h. The third group (COL-7) received COL for 7 days, at a dose of 500 mg/kg at 6-h intervals on day 1 and at a daily dose of 500 mg/kg on the following days, and blood and tissue samples were taken at the end of seventh day. The fourth group (PAR-1) was administered with PAR at a dose of 1.0 g/kg bw and was blood and tissue sampled at 24 h. The fifth group (PAR-7) received PAR at a dose of 1.0 g/kg bw on day 1 and was blood and tissue was removed at the end of day 7. The sixth group (PAR+COL-1) was administered with a combination of PAR (1 g/kg bw) and COL (500 mg/kg at 6-h intervals), and blood and tissue samples were collected at 24 h. The seventh group (PAR+COL-7) received 1.0 g/kg bw of PAR on day 1 and was given COL throughout the 7-day study period (at a dose of 500 mg/kg at 6-h intervals on day 1 and at a daily dose of 500 mg/kg on the following days). In the seventh group, blood and tissue samples were taken at the end of seventh day. Alkaline phosphatase (ALP), alanine aminotransferase (ALT), aspartate aminotransferase (AST), blood urea nitrogen (BUN), glucose, creatinine, triglyceride, total bilirubin, total protein and albumin levels/activities were analysed in the serum samples. The malondialdehyde (MDA), nitric oxide (NO), superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) levels/activities, known as oxidative stress parameters, were assayed for tissue homogenates and blood (erythrocytes/plasma); in addition, enzyme activities of GSH S-transferase (GST), cytochrome P4502E1 (CYP2E1), NADH-cytochrome b5 reductase (CYTB5), glucose-6-phosphate dehydrogenase (G6PD), NADPH-cytochrome P450 C reductase (CYTC) and glutathione (GSH) levels/activities defined as drug metabolising parameters were measured in liver homogenates. In result, it was determined that PAR caused significant alterations in some biochemical and lipid peroxidation parameters and the activities/levels of drug metabolising parameters in the liver and that COL normalised some of these parameters and reduced PAR-induced tissue damage.
Show more [+] Less [-]Effect of Cyclodextrin-Enhanced Dissolution on Mass Removal and Mass-Flux Reduction Relationships for Non-uniformly Organic Liquid Distribution in Heterogeneous Porous Media Full text
2018
Akyol, NihatHakan | Turkkan, Sevgi
A series of 2-D tank experiments were conducted to investigate the impact of non-uniform organic-liquid distribution, type of porous media, and methyl-beta-cyclodextrin (MCD) flooding on the relationship between source zone mass removal and mass-flux reduction for heterogeneous porous media. Trichloroethene was used as the model organic liquid, and MCD was used as enhanced flushing reagent. The results were also compared to those of water-flood control experiments. The results showed that the representative heterogeneous system exhibited specific non-ideal multi-step mass-flux reduction/mass removal behavior depended upon different porous media configurations. This non-ideal behavior was observed for both the water-flood and MCD flooding experiments. For all cases, early stage of trichloroethene mass removal was controlled by greater relative hydraulically accessibility of the dense non-aqueous-phase liquid (DNAPL) source distributed within the porous media matrix compared to later stage removal which was controlled by poorly hydraulically accessible mass associated with higher saturated or pooled DNAPL source zones. The results of this study significantly revealed the impact of non-uniform organic liquid distribution, flow-field heterogeneity, type of porous media, and the concentration of MCD on mass removal and mass-flux reduction behavior.
Show more [+] Less [-]Hairy Vetch Incorporated as Green Manure Inhibits Sulfathiazole Uptake by Lettuce in Soil Full text
2018
Caban, JiffRandy | Kuppusamy, Saranya | Kim, JangHwan | Yoon, Young-Eun | Kim, SongYeob | Lee, YongBok
Veterinary antibiotics like sulfonamides are frequently detected in arable lands and they can potentially contaminate food crops. It is thus of great importance to identify strategies to reduce food crops’ uptake of antibiotics. For the first time, using a pot culture experiment, sulfathiazole (STZ) uptake by lettuce (Lactuca sativa L.) grown in antibiotic-contaminated soils (10 and 100 mg STZ kg⁻¹ soil) and treated with (in)organic amendments, namely chemical fertilizer (NPK), compost, and hairy vetch, was investigated. Subsequent enhanced plant growth was witnessed when using hairy vetch treatment. The amount of antibiotic uptake was significantly reduced to 5 and 33% with hairy vetch application compared to compost or NPK application at 10 and 100 mg kg⁻¹ STZ, respectively. The total amounts of accumulated STZ in plant parts increased as the levels of STZ contaminated in soils were increased. STZ was much more abundant in the roots than the leaves. Within 30 days, the extractable STZ in the treated soils—especially with hairy vetch—diminished considerably to concentrations that are frequently detected in arable soils. We conclude that utilization of green manure (cover crop—hairy vetch) is a viable strategy for safer crop production in antibiotic-contaminated soils.
Show more [+] Less [-]Effects of the Removal of Soil Extractable Oxytetracycline Fractions on Its Bioaccumulation in Earthworm and Horsebean Full text
2018
Bao, Yanyu | Li, Yunxia | Pan, Chengrong
This study provides the evidence for oxytetracycline (OTC) uptake by earthworm and horsebean after removing extractable OTC in cinnamon soil using water (T₁), 0.1 mol/L CaCl₂ (T₂), and 0.1 mol/L Na₂EDTA-McIlvaine (T₃), respectively. The control was the soil without removing any extractable OTC. During horsebean exposure, the transformation from non-extractable to extractable fractions in soils depended mainly on the alternation of wetting and drying. Two organisms increased significantly OTC concentrations of McIlvaine-fraction in soils in comparison to the absence of organisms. The removal promoted the accumulation concentration and the bioaccumulation factor (BAF) of OTC in two organisms as the order: T₃ > T₂/T₁ > the control. And the promotion was stronger for horsebean than ones for earthworm. OTC accumulation in earthworm was mainly from the digestion absorption due to limited soil extractable OTC (0–0.976 mg/kg). OTC uptake by horsebean was directly through root uptake; therefore, the removal of soil extractable fractions decreased significantly OTC accumulation in root. However, the removal promoted OTC accumulation in shoot and OTC translocation from root to shoot, especially with the highest transfer factor (TF) in T₃ reaching up to 31.7. Maybe, in T₃, this was caused by the combined effect of root as the effective transport passageway of OTC and less loss of soil extractable OTC released during 28-day exposure. These present results demonstrated the high ecological risk of remained OTC in cinnamon soil after removing all extractable fractions due to its high accumulation in soil organisms and the strong transformation from soil non-extractable to extractable fraction under certain cultivation conditions such as alternation of wetting and drying.
Show more [+] Less [-]Influence of Anaerobic Digestion with Pretreatment on the Phytotoxicity of Sewage Sludge Full text
2018
Venegas, M. | Leiva, A. M. | Vidal, Gladys
The aim of this study is to evaluate the influence of anaerobic digestion with pretreatment on the phytotoxicity of sewage sludge. The phytotoxicity was evaluated on sewage sludge (SS) and biosolids that came from conventional anaerobic digestion (CAD) and anaerobic digestion with a pretreatment by sequential ultrasound and low-thermal hydrolysis, called advance anaerobic digestion (AAD). To compare the phytotoxicity, eight elutriate concentrations (0.5–100% v/v) from SS, CAD, and AAD were studied on three testing plants: Lactuca sativa, Raphanus sativus, and Triticum aestivum. The percentages of seed germination inhibition, root elongation, and germination index (GI) were evaluated. GI is an phytotoxicity indicator that combines seed germination and root growth, therefore reflecting a more complete estimation of toxicity. Phytotoxicity assays showed that SS, CAD, and AAD elutriates have a beneficial effect on R. sativus. Similar results were observed for T. aestivum for CAD and AAD, with GI values up to 80% in both biosolids. Only for SS, moderate toxicity was observed in T. aestivum. Moreover, L. sativa showed GI values below 50% for SS and CAD, which reflected high toxicity. Only for AAD, no presence of phytotoxic substances was observed in L. sativa. This study concluded that biosolids from AAD improved the plants’ development with a GI above 78% with respect to biosolids from SS and CAD and reduced the phytotoxicity of sewage biosolid.
Show more [+] Less [-]Water Quality in a Reservoir used for Fish Farming in Cages in Winter and Summer Periods Full text
2018
Godoy, AntonioCesar | Corrêia, ArlindoFabrício | Boscolo, WilsonRogério | Bittencourt, Fábio | Signor, Altevir | de Oliveira, JoséD. | Feiden, Aldi
This study aimed to evaluate the vertical dynamics of the water quality, in different seasons (summer and winter), in an aquaculture area of the Iguassu River electric plant reservoir (Paraná/Brasil). Water sampling was done monthly. Samples were collected from the water column layers (epilimnion, metalimnion and hypolimnion.). Water temperature, (pH), dissolved oxygen, biochemical oxygen demand, nitrite, chlorophyll, total phosphorus, orthophosphate and ammonia were the parameters evaluated. Data from each parameter were submitted to ANOVA and to Tukey’s test at the 0.05 significance level. Correlation analysis between the variables was performed using the Spearman’s test. Multivariate approach was adopted performing Royston’s multivariate normality test. A clustering analysis was performed using Ward’s minimum variance method with a Euclidean distance matrix. This study showed that fish farming did not alter the water quality during summer and winter. Heterogeneity in summer and homogeneity in winter are observed between the layers of the water column.
Show more [+] Less [-]Contamination of soils by metals and organic micropollutants: case study of the Parisian conurbation Full text
2018
Gaspéri, Johnny | Ayrault, Sophie | Moreau-Guigon, Elodie | Alliot, Fabrice | Labadie, Pierre | Budzinski, Hélène | Blanchard, Martine | Muresan, Bogdan | Caupos, Emilie | Cladière, Mathieu | Gateuille, David | Tassin, Bruno | Bordier, Louise | Teil, Marie-Jeanne | Bourges, Catherine | Desportes, Annie | Chevreuil, Marc | Moilleron, Régis
Contamination of soils by metals and organic micropollutants: case study of the Parisian conurbation Full text
2018
Gaspéri, Johnny | Ayrault, Sophie | Moreau-Guigon, Elodie | Alliot, Fabrice | Labadie, Pierre | Budzinski, Hélène | Blanchard, Martine | Muresan, Bogdan | Caupos, Emilie | Cladière, Mathieu | Gateuille, David | Tassin, Bruno | Bordier, Louise | Teil, Marie-Jeanne | Bourges, Catherine | Desportes, Annie | Chevreuil, Marc | Moilleron, Régis
Soils are playing a central role in the transfer and accumulation of anthropogenic pollutants in urbanized regions. Hence, this study aimed at examining the contamination levels of selected soils collected within and around the Paris conurbation (France). This also evaluated factors controlling contamination. Twenty-three trace and major elements as well as 82 organic micropollutants including polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), phthalates (PAEs), polybrominated diphenyl ethers (PBDEs), alkylphenols (APs), and perfluoroalkylated substances (PFASs) were analyzed. Results reinforced the concern raised by the occurrence and levels of metals such as Zn, Pb, Cu, and Hg, identified as metallic markers of anthropogenic activities, but also pointed out the ubiquitous contamination of soils by organic micropollutants in the 0.2–55,000-μg/kg dw range. For well-documented compounds like PAHs, PCBs, and to a lesser extent PBDEs, contents were in the range of background levels worldwide. The pollutant stock in tested soil was compared to the annual atmospheric input. For PAHs; Pb; and to a lesser extent Zn, Cu, Cd, Hg, Sb, PAEs, and APs, a significant stock was observed, far more important than the recent annual atmospheric fluxes. This resulted from both (i) the persistence of a fraction of pollutants in surface soils and (ii) the cumulative atmospheric inputs over several decades. Regarding PBDEs and PFASs, stronger atmospheric input contributions were observed, thereby highlighting their recent dispersal into the environment.
Show more [+] Less [-]Contamination of soils by metals and organic micropollutants: case study of the Parisian conurbation Full text
2018
Gasperi, Johnny | Ayrault, Sophie | Moreau-Guigon, Elodie | Alliot, Fabrice | Labadie, Pierre | Budzinski, Hélène | Blanchard, Martine | Muresan, Bogdan | Caupos, Emilie | Cladière, Mathieu | Gateuille, D. | Tassin, Bruno | Bordier, Louise | Teil, Marie-Jeanne | Bourges, Catherine | Desportes, Annie | Chevreuil, Marc | Moilleron, Régis | Laboratoire Eau Environnement et Systèmes Urbains (LEESU) ; AgroParisTech-École nationale des ponts et chaussées (ENPC)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12) | Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE) ; Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)) ; Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA) | Géochimie Des Impacts (GEDI) ; Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE) ; Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)) ; Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)) ; Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA) | Milieux Environnementaux, Transferts et Interactions dans les hydrosystèmes et les Sols (METIS) ; Université Pierre et Marie Curie - Paris 6 (UPMC)-École Pratique des Hautes Études (EPHE) ; Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Centre National de la Recherche Scientifique (CNRS) | École Pratique des Hautes Études (EPHE) ; Université Paris Sciences et Lettres (PSL) | Environnements et Paléoenvironnements OCéaniques (EPOC) ; École Pratique des Hautes Études (EPHE) ; Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
Spatial and temporal patterns of anthropogenic influence in a large river basin. A multidisciplinary approach | International audience | Soils are playing a central role in the transfer and accumulation of anthropogenic pollutants in urbanized regions. Hence, this study aimed at examining the contamination levels of selected soils collected within and around the Paris conurbation (France). This also evaluated factors controlling contamination. Twenty-three trace and major elements as well as 82 organic micropollutants including polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), phthalates (PAEs), polybrominated diphenyl ethers (PBDEs), alkylphenols (APs), and perfluoroalkylated substances (PFASs) were analyzed. Results reinforced the concern raised by the occurrence and levels of metals such as Zn, Pb, Cu, and Hg, identified as metallic markers of anthropogenic activities, but also pointed out the ubiquitous contamination of soils by organic micropollutants in the 0.2–55,000-μg/kg dw range. For well-documented compounds like PAHs, PCBs, and to a lesser extent PBDEs, contents were in the range of background levels worldwide. The pollutant stock in tested soil was compared to the annual atmospheric input. For PAHs; Pb; and to a lesser extent Zn, Cu, Cd, Hg, Sb, PAEs, and APs, a significant stock was observed, far more important than the recent annual atmospheric fluxes. This resulted from both (i) the persistence of a fraction of pollutants in surface soils and (ii) the cumulative atmospheric inputs over several decades. Regarding PBDEs and PFASs, stronger atmospheric input contributions were observed, thereby highlighting their recent dispersal into the environment.
Show more [+] Less [-]Effects of Titanium Dioxide Nanoparticles in Different Metabolic Pathways in the Freshwater Microalga Chlorella sorokiniana (Trebouxiophyceae) Full text
2018
Marchello, AdrianoEvandir | Barreto, DanielaMariano | Lombardi, AnaTeresa
The products that employ nanoparticles (NPs) in their composition have increased since the beginning of NP production; hence, their availability in the environment, especially in aquatic ecosystems, tends to increase. In these ecosystems, the phytoplankton is immersed in a complex matrix of nutrients, excreted materials, and other chemical compounds, which can influence the metabolic strategy of microalgae. One of the metabolic ways is mixotrophy, a situation whereby microalgae perform photosynthesis and use dissolved organic carbon at the same time. Most toxicity evaluations do not consider such a metabolic route, but this can represent a preferential metabolism in natural environments. The present study aimed at evaluating the effects of NP-TiO₂ at a log concentration range of − 3.10 to 0.89, on photosynthesis, growth, viability, and biochemical composition of the microalgae Chlorella sorokiniana during photoautotrophic and mixotrophic growth (glucose as the organic carbon source). The results showed lower chlorophyll a and photosynthetic activity in mixotrophy than in photoautotrophy, which can be due to a decreased need for photosynthesis in mixotrophy. Photoautotrophy cultures were sensitive to NPs, reaching 39% of viability at log 0.89, while in mixotrophy, cell viability was not affected by NPs. The biochemical composition and cell density changed as a function of NP concentrations, with increase in the protein/carbohydrate ratio in both treatments. The results showed that C. sorokiniana is more resistant to NPs during mixotrophic growth, but with changes in biochemical composition, whereas the photoautotrophic cultures were more sensitive to the increase in NP concentrations.
Show more [+] Less [-]Industrial Symbiosis Between the Winery and Environmental Industry Through the Utilization of Grape Marc for Water Desalination Containing Copper(II) Full text
2018
Bustos, G. | Calvar, S. | Vecino, X. | Cruz, J.M. | Moldes, A.B.
A bioadsorbent formulated with a secondary raw material, consisting of grape marc, subjected to a bioxidize process and entrapped in calcium alginate beads, was used for the desalination of water containing copper(II) sulfate. Experiments were established under different experimental conditions varying the concentration of contaminant, the amount of bioadsorbent, and the extraction time through response surface methodology. The most significant variable in the removal of copper(II) sulfate was the amount of bioadsorbent employed, followed by the extraction time; whereas, the adsorbent capacity was more influenced by the amount of contaminant and the amount of bioadsorbent used. At the highest concentration of copper(II) sulfate (0.15 mol/L), the equations obtained predict that the bioadsorbent has a capacity of 2785 mg/g and produces a copper(II) removal about 43% using low adsorbent/water ratios, 1:10 (v/v), and maximum extraction times; whereas, it would remove 97.2% of copper(II) sulfate in 5 min, using adsorbent/water ratios close to 1:2 (v/v), with capacity values, in this case, around 1800 mg/g. The encapsulation of the bioxidize adsorbent increased its capacity to 30% and allowed the precipitation of sulfate ions as calcium sulfate. The results obtained in this work could presume advances for promoting the industrial symbiosis between winery and environmental industries. Graphical abstract Utilization of secondary raw material, consisting of bioxidize grape marc from winery industry, as bioadsorbent encapsulated in calcium alginate beads, for the removal of copper(II) sulfate from water
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