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Environmentally relevant bisphenol A concentrations effects on the seagrass Cymodocea nodosa different parts elongation: perceptive assessors of toxicity Full text
2020
Malea, Paraskevi | Kokkinidi, Danae | Kevrekidou, Alkistis | Adamakis, Ioannis-Dimosthenis S.
Toxicity data on bisphenol A (BPA) effects on aquatic macrophytes remain scarce. Therefore, environmentally relevant BPA concentrations (0.03, 0.1, 0.3, 0.5, 1, and 3 μg L⁻¹) were tested on the seagrass Cymodocea nodosa different parts length increase. All plant parts, at low BPA concentrations (0.03–0.3 μg L⁻¹), elongated equally to the control, while their lengthening and elongation rates gradually decreased by increasing BPA concentrations. A gradual increase of “Toxicity index” with increasing BPA concentrations was observed but was lower for juvenile blades and higher for plagiotropic rhizomes and adult leaves. In all parts, the LOECs were 0.3 and the NOECs 0.1 μg L⁻¹ at 10th day. Juvenile blades displayed, under acute stress, lengthening inhibition at lower concentrations than the rhizomes and adult blades, but at a lower extent. The EC₅₀ values were lower for the rhizome internodes, followed by the adult blades and higher for the juvenile blades. Using as a biological “endpoint” the elongation, all C. nodosa parts and specifically the rhizomes and adult blades, followed by intermediate blades, adult sheaths, and juvenile blades, seemed to be sensitive BPA toxicity assessors. The evaluation of the relative sensitivity of the different parts to BPA toxicity could help identify the most suitable seagrass part for early diagnosis of the risk posed by BPA to seagrass meadows and could constitute a valuable tool to derive the seawater quality criteria and to be used in BPA monitoring programs for rational management of the coastal environment.
Show more [+] Less [-]Environmentally friendly synthesis of Fe2O3@SiO2 nanocomposite: characterization and application as an adsorbent to aniline removal from aqueous solution Full text
2020
Rahdar, Abbas | Rahdar, Somayeh | Labuto, Georgia
Silica-based nanocomposite syntheses employ many harmful substances, which, in turn, demand the development of new synthetic environmental-friendly routes that meet the principles of green chemistry. In this work, we present a novel magnetic adsorbent, Fe₂O₃@SiO₂ nanocomposite (Fe@SiNp), successfully obtained without surfactant, employing an electrochemical method. We characterized the nanocomposite and then applied it to remove aniline from the water medium. Characterization was carried out by vibrating-sample magnetometry (VSM), X-ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy (FT-IR). The parameters to the adsorptive removal of aniline were successfully optimized, which made possible to remove 71.04 ± 0.06% (126.6 ± 2.0 mg/g) from a 100 mg/L aniline solution at pH 6 and 323 K, by employing around 50 mg of Fe@SiNp, at a contact time of 40 min. The adsorption of aniline by Fe@SiNp is a spontaneous and exothermic process according to the pseudo-second-order kinetic model (r² = 1 at 20 mg/L aniline concentration) and the Freundlich isotherm model (r² = 0.9986).
Show more [+] Less [-]Comparative effects on arsenic uptake between iron (hydro)oxides on root surface and rhizosphere of rice in an alkaline paddy soil Full text
2020
Yang, Yongqiang | Hu, Hongqing | Fu, Qingling | Xing, Zhiqiang | Chen, Xingyu | Zhu, Jun
The iron (Fe) (hydro)oxides deposited around rice roots play an important role in arsenic (As) sequestration in paddy soils, but there is no systematic study on the relative importance of Fe (hydro)oxides on root surface and in rhizosphere soil in limiting As bioavailability. Twenty-seven rice genotypes were selected to investigate effects of Fe (hydro)oxides on As uptake by rice in an alkaline paddy soil. Results indicated that the As content was positively correlated with the Fe content on root surface, and most of As (88–97%) was sequestered by poorly crystalline and crystalline Fe (hydro)oxides in the alkaline paddy soil. The As sequestration by Fe (hydro)oxides on root surface (IASᵣₒₒₜ 16.8–25.0 mg As/(g Fe)) was much higher than that in rhizosphere (IASᵣₕᵢzₒ 1.4–2.0 mg As/(g Fe)); therefore, in terms of As immobilization, the Fe (hydro)oxides on root surface were more important than that in rhizosphere. However, the As content in brown rice did not have significant correlation with the As content on root surface but was significantly correlated (R² = 0.43, P < 0.05) with the partition ratio (PRAₛ = IASᵣₒₒₜ/IASᵣₕᵢzₒ) of As sequestration on root surface and in rhizosphere, which suggested that Fe (hydro)oxides on root surface did not play the controlling role in lowering As uptake, and the partition ratio PRAₛ would be a better indicator to evaluate effects of Fe (hydro)oxides around roots on As uptake by rice.
Show more [+] Less [-]Effects of multiple antibiotics on greenhouse gas and ammonia emissions during swine manure composting Full text
2020
Chen, Zhiqiang | Wu, Yiqi | Wen, Qinxue | Ni, Hongwei | Chai, Chunrong
Antibiotics are commonly used in intensive farming, leading to multiple antibiotic residue in livestock waste. However, the effects of multiple antibiotics on the emissions of greenhouse gas and ammonia remain indistinct. This paper selects sulfamethoxazole and norfloxacin to represent two different types of antibiotics to explore their effects on gaseous emissions. Four treatments including CK (control), SMZ (spiked with 5 mg kg⁻¹ DW sulfamethoxazole), NOR (spiked with 5 mg kg⁻¹ DW norfloxacin), and SN (spiked with 5 mg kg⁻¹ DW sulfamethoxazole and 5 mg kg⁻¹ DW norfloxacin) were composted for 65 days. Coexistence of sulfamethoxazole and norfloxacin facilitated the biodegradation of organic carbon, and significantly (p < 0.05) increased the cumulative CO₂ emission by 31.9%. The cumulative CH₄ emissions were decreased by 6.19%, 23.7%, and 27.6% for SMZ, NOR, and SN, respectively. The total NH₃ volatilization in SMZ and NOR rose to 1020 and 1190 mg kg⁻¹ DW, respectively. The individual existence of sulfamethoxazole significantly (p < 0.05) ascended the N₂O emission rate in the first 7 days due to the increase of NO₂⁻-N content. In addition, coexistence of sulfamethoxazole and norfloxacin notably dropped the total greenhouse gas emission (subtracting CO₂) by 15.5%.
Show more [+] Less [-]Structured cobalt oxide catalysts for VOC abatement: the effect of preparation method Full text
2020
Topka, Pavel | Dvorakova, Michaela | Kšírová, Petra | Perekrestov, Roman | Čada, Martin | Balabánová, Jana | Koštejn, Martin | Jirátová, Květuše | Kovanda, František
Magnetron sputtering was employed for the deposition of cobalt oxide thin films on stainless steel meshes. Catalysts prepared by sputtering in inert and oxidation atmosphere were compared with those obtained by electrochemical deposition and hydrothermal synthesis. Systematic characterization using X-ray diffraction, scanning electron microscopy, N₂ physisorption, infrared spectroscopy, Raman spectroscopy, and temperature-programmed reduction by hydrogen allowed detailed monitoring of their physicochemical properties. Ethanol gas-phase oxidation was employed as a model reaction to reveal the catalytic performance of the catalysts. It was shown that the catalyst prepared by magnetron sputtering in oxidation atmosphere exhibited the best mechanical stability among all studied catalysts. Moreover, its catalytic activity was 18 times higher than that of pelletized commercial cobalt oxide.
Show more [+] Less [-]Ellagic acid ameliorates lung damage in rats via modulating antioxidant activities, inhibitory effects on inflammatory mediators and apoptosis-inducing activities Full text
2020
Aslan, Abdullah | Hussein, Yousif Taha | Gok, Ozlem | Beyaz, Seda | Erman, Orhan | Baspinar, Serpil
Phytochemicals is considered one of the most effective and safe alternative therapy against oxidative linked lung diseases. Ellagic acid (EA), an important component of fruits, nuts, and vegetables, are partly responsible for their beneficial health effects against oxidation-related diseases. In the present study, we investigated the ameliorative effect of EA on lung damage induced by carbon tetrachloride (CCl₄) in Wistar male albino rats. Thirty-six male rats (n = 36, 8-week old) were divided into 4 groups, each with 9 rats. The groups were: Control group: received standard diet; EA group: administered with EA (10 mg/kg body weight, intraperitoneal); CCl₄ group: administered with CCl₄ (1.5 mg/kg body weight, intraperitoneal); EA+CCl₄ group: administered with EA and CCl₄. . The rats were decapitated at the end of experimental period of 8 weeks and the lung tissues were examined. CCl₄-induced rats showed elevation in the expressions of inflammatory proteins, nuclear factor kappa b (NF-κB), cyclooxygenase-2 (COX-2), and pro-inflammatory cytokine, tumor necrosis factor alpha (TNF-α); and the indicator of lipid peroxidation, malondialdehyde (MDA). Intraperitoneal administration of EA significantly reduced the levels of these markers. EA administration increased the protein expression levels of nuclear factor erythroid 2-related factor 2 (Nrf-2) and enhanced the activity of glutathione (GSH) and catalase enzyme (CAT). In addition, EA administration increased the expression levels of the executioner protein of apoptosis, caspase-3, and decreasing pro-survival protein, B cell lymphoma-2 (Bcl-2). In conclusion, these results establishes the protective role of EA in the treatment of lung damage and that in the future, this may have the potential to be used as a medication for the prevention or attenuation of lung diseases. Graphical abstract
Show more [+] Less [-]Immobilization of fluoride in the sediment of mine drainage stream using loess, Northwest China Full text
2020
Li, Yueyue | Wang, Shengli | Sun, Huiling | Huang, Wen | Nan, Zhongren | Zang, Fei | Li, Yepu
Fluoride (F) is a necessary trace element in the human body, which would lead to some diseases if human body lacks or accumulates it excessively (1–1.5 mg d⁻¹). Fluoride contamination in sediments has become more and more serious, which has potential hazards to human body. In this paper, a novel sorbent (loess) was proposed to immobilize trace element F in sediment. The effectiveness of loess on F stabilization was evaluated by decreasing F bioavailability in contaminated sediment. The loess and the sediment were mixed at different proportions for stabilization. About 70 days after the application of loess, the soil column was subject to simulate acid rain leaching test to observe the leaching-migration of F, which can be used to predict the leaching migration of F in the study area. The results showed that when the loess dose was 5 kg, the loess converted highly effective fractions of F (i.e., water-soluble and exchangeable fractions) into a more stable state (i.e., residual state). After 30 days of leaching with HNO₃ solution with pH at 3.0, the lowest concentration of F was found in the leachate of soil column with 2 kg loess application. Correlation analysis showed that the F concentration in soil column profile was affected by CaCO₃, EC, pH, and OM, of which, pH and CaCO₃ have greater influence than other factors.
Show more [+] Less [-]Lethal and sublethal exposure of Hemichromis bimaculatus (Gill, 1862) to malachite green and possible implications for ornamental fish Full text
2020
Souza, Augusto César Paes | Melo, Karina Motta | de Azevedo, Luana França Calandrini | de Almada Vilhena, Andryo Orfi | Nagamachi, Cleusa Yoshiko | Pieczarka, Júlio César
Malachite green (MG) is a triphenylmethane dye that is widely used in aquaculture as a fungicide, bactericide, ectoparasiticide, and antiprotozoal. There is great debate regarding the potential for this compound to trigger adverse effects. Here, we review the previous findings and then evaluate the lethal and sublethal effects of MG in the species Hemichromis bimaculatus (jewelfish). The lethal concentration for 50% of the fish in 96 h was 1 mg/L. We observed a dose-dependent increase in the percentage of fish mortality as well as physical and behavioral changes. We further found that the highest tested sublethal dose significantly increased the DNA damage index identified using the comet assay (74.97 ± 13.8 at a significant level of P < 0.05 for the 0.75 mg/L concentration), but did not significantly alter the results of the micronucleus test. Although our results suggest that MG confers risks on exposed fish, the findings were significant only at the highest exposure concentration (0.75 mg/L). At lower concentrations (0.25 mg/L and 0.5 mg/L), no adverse effect was observed. The maximum MG concentration recommended for use in ornamental fish farming is 0.2 mg/L. Therefore, our results suggest that, specifically for the parameters analyzed in this work, MG does not have any adverse effect when users strictly adhere to the recommended concentration criteria for ornamental fish.
Show more [+] Less [-]Removal of rhodamine 6G from synthetic effluents using Clitoria fairchildiana pods as low-cost biosorbent Full text
2020
da Silva, Andreza Miranda Barata | Serrão, Naiany Oliveira | de Gusmão Celestino, Gustavo | Takeno, Mitsuo Lopes | Antunes, Nicanor Tiago Bueno | Iglauer, Stefan | Manzato, Lizandro | de Freitas, Flávio Augusto | Maia, Paulo José Sousa
Many organic dye pollutants have been identified in rivers and lakes around the world, and concern is growing with them as they cause serious changes in the ecological balance of aquatic environments. One of these dyes is rhodamine R6G, which is very water-soluble and has a high corrosive power. Therefore, Clitoria fairchildiana (CF) pods were used as a biosorbent to remove R6G from synthetic dye effluents. CF was characterized by infrared spectroscopy, thermogravimetric analysis, x-ray diffraction, elemental analysis, Boehm titration, and zero charge point measurements. The influence of various factors, such as solution pH, contact time, adsorbent mass, and concentration of R6G, was studied using batch equilibrium experiments. The optimum contact time to reach equilibrium was found to be 15 min, while the optimum adsorbent dose was 8 g L⁻¹. The maximum adsorption capacity of CF (73.84 mg g⁻¹) was observed at pH 6.4 and 298.15 K. Adsorption kinetics followed a pseudo-second-order law, and the isotherm could be best fitted with a Liu model. The obtained thermodynamic parameters indicate that the adsorption of R6G is spontaneous and enthalpy-driven. We thus conclude that CF is an efficient, green, and readily available biosorbent for dye removal from wastewater.
Show more [+] Less [-]Interactions between dietary habits and home environmental exposures on respiratory symptoms in Romanian school children: an analysis of data from the SINPHONIE project Full text
2020
Lawrence, Wayne R. | Lin, Shao | Lin, Ziqiang | Gurram, Namratha | Neamtiu, Iulia A. | Csobod, Eva | Gurzau, Eugen
In this study, we investigated the interactions between household pollutants and dietary habits on children’s respiratory health. Our cross-sectional study collected self-reported information including health symptoms (allergy-like, asthma-like, and flu-like symptoms), home characteristics, dietary habits, and demographic information from questionnaires administered to parents of 280 school children in Romania. Unconditional logistic regression and stratified analyses were used to assess the interactions between dietary factors and environmental exposures on health symptoms among children, controlling for sociodemographic characteristics and co-exposures. We found that frequency of fruit consumption had significant interaction with residing near heavy traffic on allergy-like symptoms among children (p = 0.036). However, no association was observed by frequency of fruit consumption. Although no significant interaction was observed, we found that students with infrequent fruit consumption and residing near heavy traffic roads had elevated odds of asthma-like (POR 6.37; 95% CI 1.22, 33.29) and flu-like symptoms (POR 3.75; 95% CI 1.12, 11.86) than those who frequently consumed fruits. Likewise, low vegetable consumption was associated with increased asthma-like symptoms (POR 2.93; 95% CI 1.04, 8.24). Increased odds of asthma-like symptoms were observed among school children that resided near heavy traffic roads and frequently consumed milk (POR 2.80; 95% CI 1.24, 6.31) and yoghurt (POR 2.86; 95% CI 1.05, 7.75) compared to those that infrequently consumed dairy. Our findings suggest that frequent fruit and vegetable consumption may mitigate the negative effects of exposure to heavy traffic near dwelling on respiratory symptoms in Romanian children.
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