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Association between inflammation processes, DNA damage, and exposure to environmental pollutants Полный текст
2017
Barth, Anelise | Brucker, Natália | Moro, Angela M. | Nascimento, Sabrina | Goethel, Gabriela | Souto, Caroline | Fracasso, Rafael | Sauer, Elisa | Altknecht, Louise | da Costa, Bárbara | Duarte, Marta | Menezes, Camila B. | Tasca, Tiana | Arbo, Marcelo D. | Garcia, Solange Cristina
Environmental exposure to pollutants, especially polycyclic aromatic hydrocarbons (PAHs), could lead to carcinogenesis development. However, there is a gap on the mechanisms involved in this effect. Therefore, the aim of this study was to investigate the potential relationship between exposure to environmental air pollution and inflammation process in DNA damage in taxi drivers. This study included 45 taxi drivers and 40 controls; non-smokers composed both groups. Biological monitoring was performed through quantification of urinary 1-hydroxypyrene (1-OHP). ICAM-1 (CD54) expression, NTPDase activity, inflammatory cytokine (IL-1β, IL-6, IL-10, TNF-α and IFN-γ) levels, and comet and micronucleus assays were evaluated. The results demonstrated that 1-OHP levels, ICAM-1 expression, NTPDase activity, and DNA damage biomarkers (% tail DNA and micronucleus frequency) were increased in taxi drivers compared to the control group (p < 0.01). Moreover, significant associations were found between 1-OHP levels and ICAM-1 expression, % tail DNA, and micronucleus frequency (p < 0.05). Besides, pro-inflammatory cytokine levels were positively correlated to % tail DNA and micronucleus frequency (p < 0.001). Our findings suggest an important association between environmental exposure to air pollution with increase of ICAM-1 expression and NTPDase activity in taxi drivers. Additionally, the multiple regression linear-analysis demonstrated association between IL-6 and DNA damage. Thus, the present study has provided important evidence that, in addition to environmental exposure to air pollutants, the inflammation process may contribute to DNA damage.
Показать больше [+] Меньше [-]Degradation of the insecticide propoxur by electrochemical advanced oxidation processes using a boron-doped diamond/air-diffusion cell Полный текст
2017
Guelfi, Diego Roberto Vieira | Gozzi, Fábio | Sirés, Ignasi | Brillas, Enric | Machulek, Amílcar Jr | de Oliveira, Silvio César
A solution with 0.38 mM of the pesticide propoxur (PX) at pH 3.0 has been comparatively treated by electrochemical oxidation with electrogenerated H₂O₂ (EO-H₂O₂), electro-Fenton (EF), and photoelectro-Fenton (PEF). The trials were carried out with a 100-mL boron-doped diamond (BDD)/air-diffusion cell. The EO-H₂O₂ process had the lowest oxidation ability due to the slow reaction of intermediates with •OH produced from water discharge at the BDD anode. The EF treatment yielded quicker mineralization due to the additional •OH formed between added Fe²⁺ and electrogenerated H₂O₂. The PEF process was the most powerful since it led to total mineralization by the combined oxidative action of hydroxyl radicals and UVA irradiation. The PX decay agreed with a pseudo-first-order kinetics in EO-H₂O₂, whereas in EF and PEF, it obeyed a much faster pseudo-first-order kinetics followed by a much slower one, which are related to the oxidation of its Fe(II) and Fe(III) complexes, respectively. EO-H₂O₂ showed similar oxidation ability within the pH range 3.0–9.0. The effect of current density and Fe²⁺ and substrate contents on the performance of the EF process was examined. Two primary aromatic products were identified by LC-MS during PX degradation.
Показать больше [+] Меньше [-]Concentrations and inhalation risk assessment of short-chain polychlorinated paraffins in the urban air of Dalian, China Полный текст
2017
Zhu, Xiuhua | Bai, Hao | Gao, Yuan | Chen, Jiping | Yuan, Heping | Wang, Longxing | Wang, Wei | Dong, Xuewei | Li, Xiaoxiao
The concentrations of short-chain polychlorinated paraffins (SCCPs) in the urban air of Dalian, China, were monitored from March to October 2010 and from September to October 2016 with active high-volume sampler. The total concentration of SCCPs (particulate phase + gas phase) ranged from 15.12 to 66.44 ng m⁻³, with an average of 30.26 ng m⁻³ in 2010, and 65.30 to 91.00 ng m⁻³, with an average of 78.15 ng m⁻³ in 2016. Hexa-chlorinated dodecane and hexa-chlorinated undecane are the predominant components in the gas phase, while octa-chlorinated undecane and hepta-chlorinated tridecane are dominant in the particulate phase. In 2010, 82.57–97.16% of the total SCCPs were found in the gas phase, except that in winter, where 63.11% of the total SCCPs were in the particulate phase; the air concentrations of SCCPs in gas phase were summer > autumn > spring > winter, which was positively correlated with the change of the average ambient temperature, while it was the contrary in particulate phase. In autumn, the gas phase and the total air concentration of SCCPs in 2016 were 2.57 times more than that in 2010, while the congener group patterns of SCCPs were similar. Spearman’s rank correlation analysis between the concentrations of SCCPs with meteorological parameters was conducted. The gas-particle distribution was examined through the relationship of the logarithm of the gas-particle partition coefficient with that of the subcooled vapor pressure and the octanol-air partitioning coefficient of SCCPs. Results indicated that the absorption mechanisms contributed more to the partitioning process. The exposure risk of SCCPs was evaluated, which illustrated that the estimated exposure of SCCPs via the outdoor environment in Dalian did not exceed the health concern threshold of the European risk assessment.
Показать больше [+] Меньше [-]Sorption of thiabendazole in sub-tropical Brazilian soils Полный текст
2017
de Oliveira Neto, Odilon França | Arenas, Alejandro Yopasa | Fostier, Anne Hélène
Thiabendazole (TBZ) is an ionizable anthelmintic agent that belongs to the class of benzimidazoles. It is widely used in veterinary medicine and as a fungicide in agriculture. Sorption and desorption are important processes influencing transport, transformation, and bioavailability of xenobiotic compounds in soils; data related to sorption capacity are therefore needed for environmental risk assessments. The aim of this work was to assess the sorption potential of TBZ in four Brazilians soils (sandy, sandy-clay, and clay soils), using batch equilibrium experiments at three pH ranges (2.3–3.0, 3.8–4.2, and 5.5–5.7). The Freundlich sorption coefficient (K F) ranged from 9.0 to 58 μg¹–¹/ⁿ (mL) ¹/ⁿ g⁻¹, with higher values generally observed at the lower pH ranges (2.3–3.0 and 3.8–4.2) and for clay soils. The highest organic carbon-normalized sorption coefficients (KOC) obtained at pH 3.8–5.7 (around the natural pH range of 4.1–5.0) for both clay soils and sandy-clay soil were 3255 and 2015 mL g⁻¹, respectively. The highest correlations K F vs SOM (r = 0.70) and K F vs clay content (r = 0.91) were observed at pH 3.8–4.2. Our results suggest that TBZ sorption/desorption is strongly pH dependent and that its mobility could be higher in the studied soils than previously reported in soils from temperate regions.
Показать больше [+] Меньше [-]An innovative application of extended exergy analysis into an industrial park Полный текст
2017
Fan, Yupeng | Qiao, Qi | Fang, Lin
Exergy is a thermodynamic term used to account all possible useful work theoretically throughout one process when it is brought into equilibrium with its environment. It however cannot directly incorporate non-physical flows, which can be accounted by extensions of the exergy consumption method. Extended exergy, which builds a bridge between thermal and anthropic dimensions, can both measure resource consumption and economic system. In this study, we applied extended exergy analysis to analyze an industrial park, including material consumption, social investment, and environmental influence. The total extended exergy consumption in the study park amounts to 2.52 EJ. The material-based exergy occupies the largest exergy consumption, followed by capital exergy, environmental remediation exergy, and labor exergy in decreasing order. The exergy capacity was proposed to depict the conversion ability from exergy consumption into economic benefits. In the study area, electronic information industry has the largest exergy capacity with a value of 70 RMB/GJ, indicating a high conversion power from exergy to money. New energy vehicles and parts manufacturing occupies bottom rung in terms of exergy capacity. From the view of material consumption, other industry consumed a lot more exergy compared to electronic information industry; for the environmental remediation, other industry has the lowest exergy capacity, indicating it discharged more pollutants than other clusters to output the same amount of money. Therefore, other industry needs to be urgently transformed and upgraded. The study could help to optimize industrial structure and environmental management in industrial parks.
Показать больше [+] Меньше [-]Variation of microbial communities and functional genes during the biofilm formation in raw water distribution systems and associated effects on the transformation of nitrogen pollutants Полный текст
2017
Chen, Wei | Gu, Yanmei | Xu, Hang | Liu, Zhigang | Lu, Chunhui | Lin, Chenshuo
This study aimed to investigate the variation of microbial communities and functional genes during the biofilm formation in raw water distribution systems without prechlorination and associated effects on the transformation of nitrogen pollutants by using a designed model pipe system. The results showed the transformation of nitrogen pollutants was obvious during the biofilm formation. The richness and diversity of the microbial communities changed significantly. The higher abundance of Nitrospirae in biofilm samples significantly contributed to biological nitrification. In particular, the stable content of Bacteroidetes in the biofilm and soluble microbial products released by the biomass might have enhanced the increase in dissolved organic nitrogen. In addition, the variation tendency of nitrogen functional gene abundances and their strong effects on NH₄ ⁺-N, NO₂ ⁻-N, and NO₃ ⁻-N transformation were clearly observed. These findings provide new insights into the evolution of microbial communities and functional genes during the initial operation period of real-world raw water distribution pipes and highlight management and possible safety issues in the subsequent water treatment process.
Показать больше [+] Меньше [-]Enrichment and oral bioaccessibility of selected trace elements in fly ash-derived magnetic components Полный текст
2017
Bourliva, Anna | Papadopoulou, Lambrini | Aidona, Elina | Simeonidis, Konstantinos | Vourlias, George | Devlin, Eamonn | Sanakis, Yiannis
The mineralogy, morphology, and chemical composition of magnetic fractions separated from fly ashes (FAs) originating from Greek lignite-burning power plants was investigated. The oral bioaccessibility of potentially harmful elements (PHEs) from the fly ash magnetic fractions (FAMFs) was also assessed using in vitro gastrointestinal extraction (BARGE Unified Bioaccessibility Method, UBM). The FAMFs isolated were in the range 4.6–18.4%, and their mass specific magnetic susceptibility ranged from 1138 × 10⁻⁸ to 1682 × 10⁻⁸ m³/kg. XRD analysis and Mossbauer spectroscopy indicated that the dominant iron species were Fe-rich aluminosilicate glass along with magnetite, hematite, and maghemite (in decreasing order). The raw FAs exhibited differences in their chemical composition, indicating the particularity of every lignite basin. The elemental contents of FAMFs presented trends with fly ash type; thus, the FAMFs of high-Ca FAs were enriched in siderophile (Cr, Co, Ni) and lithophile (Cs, Li, Rb) elements and those separated from low-Ca FAs were presented depleted in chalcophile elements. Based on UBM extraction tests, the PHEs were more bioaccessible from the non-magnetic components of the FAs compared to the magnetic ones; however, the bioaccessible fractions estimated for the FAMFs were exceeding 40 % in many cases. Arsenic was found to be significantly bioaccessible (median ~ 80 %) from FAMFs despite the lower As contents in the magnetic fraction.
Показать больше [+] Меньше [-]Electrochemical techniques for evaluating short-chain fatty acid utilization by bioanodes Полный текст
2017
Huang, Wendy | Kim, Younggy
The utilization of propionic, n-butyric, and isobutyric acids in microbial electrolysis cells (MECs) was examined by monitoring individual short-chain fatty acid concentration and using electrochemical techniques, such as linear sweep voltammetry (LSV) and electrochemical impedance spectroscopy (EIS). When n-butyric or isobutyric acid was provided as a single substrate, acetic acid was consistently observed in experiments, indicating that acetic acid was produced as a byproduct and utilized by exoelectrogenic bacteria as an additional substrate in MECs. When isobutyric acid was given as a sole substrate, the applied potential governed the electric current (i.e., rate of substrate utilization). In addition, the coulombic efficiency was substantially high (90%), indicating direct utilization of isobutyric acid by exoelectrogenic bacteria. However, the coulombic efficiency was relatively low (30–60%) when n-butyric acid was provided as a sole substrate. In another experiment, the magnitude of electric current was more dependent on the concentration of acetic acid than that of other short-chain fatty acids. In the EIS analysis, the exchange current was found to be a more reliable indicator of substrate favorability than the charge transfer resistance.
Показать больше [+] Меньше [-]Sulfur dioxide inhibits expression of mitochondrial oxidative phosphorylation genes encoded by both nuclear DNA and mitochondrial DNA in rat lungs Полный текст
2017
Qin, Guohua | Wang, Jiaoxia | Sang, Nan
Epidemiological studies show that sulfur dioxide (SO₂), a major air pollutant, is associated with the morbidity and mortality of respiratory tract diseases. The aim of the present study was to determine the effects of SO₂ on mitochondria and the corresponding molecular characterization in the lung. Male Wistar rats were exposed to 0, 3.5, 7, and 14 mg/m³ SO₂ (4 h/day, 30 days). Mitochondrial dysfunction including decreases of cytochrome c oxidase (COX) activity and mitochondrial membrane potential (MMP) was observed in the lungs of rats after SO₂ inhalation. We showed that total mitochondrial DNA (mtDNA) content was significantly decreased in the lungs from rats exposed to SO₂. Furthermore, SO₂ repressed the expression of complex IV and V subunits encoded by both nuclear DNA (nDNA) and mtDNA. Moreover, such changes were accompanied by depressions of three regulatory factors: peroxisome proliferator-activated receptor gamma coactivator 1α (PGC-1α), nuclear respiratory factor 1 (NRF1), and mitochondrial transcription factor A (TFAM). The findings suggest that SO₂ exposure induced mitochondrial dysfunction in rat lungs. Both nDNA and mtDNA are involved in SO₂-induced depression of mitochondrial biogenesis in the lungs. There might be a tissue-specific response of mitochondrial biosynthesis to SO₂ inhalation. Such impairment may lead to cellular dysfunction and eventually lung diseases.
Показать больше [+] Меньше [-]Agricultural effluent treatment in biobed systems using novel substrates from southeastern Mexico: the relationship with physicochemical parameters of biomixtures Полный текст
2017
Góngora-Echeverría, Virgilio René | Martin-Laurent, Fabrice | Quintal-Franco, Carlos | Giácoman Vallejos, Germán | Ponce-Caballero, Carmen
Agricultural effluent treatment in biobed systems using novel substrates from southeastern Mexico: the relationship with physicochemical parameters of biomixtures Полный текст
2017
Góngora-Echeverría, Virgilio René | Martin-Laurent, Fabrice | Quintal-Franco, Carlos | Giácoman Vallejos, Germán | Ponce-Caballero, Carmen
Misuse of pesticides in farming activities leads to contamination of drinking water sources and is responsible for animal and human health problems. The biobeds are practicable option to minimize contamination by pesticides during preparation, use and washing of equipment for pesticide treatments. This research aimed at testing substrate mixtures to optimize biobed efficiency to remove pesticides under the climate of the Yucatan (México). Agricultural soil and 11 mixtures adding vegetable compost, sisal pulp, corn stover and seaweed were tested under controlled conditions. Each biomixture was exposed to a mixture of five pesticides (2,4-diclorophenoxyacetic acid “2,4-D” [1.08 mg cm⁻³], atrazine [2.50 mg cm⁻³], carbofuran [0.23 mg cm⁻³], diazinon [0.34 mg cm⁻³], and glyphosate [0.36 mg cm⁻³]) in a period of 41 days. Monitoring of the dissipation of pesticide residues showed that pesticides were quickly dissipated in soil at microcosm level experiment, while at two critical times of 20 and 41 days, all mixtures of substrates (biomixtures) were efficient in dissipation of high concentrations of pesticide in a short time (>99%). Time, biomixture and type of pesticide were shown to be the main parameters influencing pesticide dissipation (P < 0.05). Several other physicochemical parameters of the biomixtures, such as organic matter (OM), lignin, water holding capacity (WHC), and pH, were also significant on pesticide dissipation (P < 0.05), being pH the most significant.
Показать больше [+] Меньше [-]Agricultural effluent treatment in biobed systems using novel substrates from southeastern Mexico: the relationship with physicochemical parameters of biomixtures Полный текст
2017
Góngora-Echeverría, Virgilio René | Martin-Laurent, Fabrice | Quintal-Franco, Carlos | Giácoman-Vallejos, German | Ponce-Caballero, Carmen | Facultad de Ingeniería ; Universidad de la República [Montevideo] (UDELAR) | 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-Université Bourgogne Franche-Comté [COMUE] (UBFC)
EABIOmE INRA | Misuse of pesticides in farming activities leads to contamination of drinking water sources and is responsible for animal and human health problems. The biobeds are practicable option to minimize contamination by pesticides during preparation, use and washing of equipment for pesticide treatments. This research aimed at testing substrate mixtures to optimize biobed efficiency to remove pesticides under the climate of the Yucatan (México). Agricultural soil and 11 mixtures adding vegetable compost, sisal pulp, corn stover and seaweed were tested under controlled conditions. Each biomixture was exposed to a mixture of five pesticides (2,4-diclorophenoxyacetic acid “2,4-D” [1.08 mg cm−3], atrazine [2.50 mg cm−3], carbofuran [0.23 mg cm−3], diazinon [0.34 mg cm−3], and glyphosate [0.36 mg cm−3]) in a period of 41 days. Monitoring of the dissipation of pesticide residues showed that pesticides were quickly dissipated in soil at microcosm level experiment, while at two critical times of 20 and 41 days, all mixtures of substrates (biomixtures) were efficient in dissipation of high concentrations of pesticide in a short time (>99%). Time, biomixture and type of pesticide were shown to be the main parameters influencing pesticide dissipation (P < 0.05). Several other physicochemical parameters of the biomixtures, such as organic matter (OM), lignin, water holding capacity (WHC), and pH, were also significant on pesticide dissipation (P < 0.05), being pH the most significant.
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