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In situ evaluation of the NOx removal efficiency of photocatalytic pavements: statistical analysis of the relevance of exposure time and environmental variables
2019
Jiménez-Relinque, Eva | Hingorani, Ramón | Rubiano, Francisco | Grande, Maria | Castillo, Ángel | Castellote, Marta
In the recent past, the NOₓ removal efficiency of photocatalytic materials has been subject of many studies with promising results. However, many of these studies involve laboratory tests carried out under standardized climatic exposure conditions, often not representative of the real-world environment. With the aim to bridge this gap, selected photocatalytic materials have been applied to different substrates in outdoor demonstrator platforms at pilot scale as part of the project LIFE-PHOTOSCALING. The paper presents the results of in situ measurements of NOₓ removal efficiency of the materials, performed during 17 months. Statistical models accounting for the influence of exposure time and relevant environmental variables are derived. They suggest that photocatalytic emulsions on the tested asphalt experience a significant loss of activity over time irrespective of climatic conditions. The efficiency of photocatalytic slurries on asphalt and of concrete tiles, with the photocatalyst applied on surface or in bulk, mainly depends on substrate humidity.
Afficher plus [+] Moins [-]Agricultural and domestic pesticides in house dust from different agricultural areas in France
2019
Pesticides have been associated with various pathologies, and there is growing evidence of pesticide presence in domestic environments. However, most available studies focused on a limited number of pesticides or households, and few have been conducted in Europe. We aimed to assess indoor pesticide contamination by screening the prevalence of 276 pesticides and ten pesticide metabolites, in French households from different agricultural and urban areas. We sampled indoor dust from 239 households in 2012, proximate to orchards (n = 69), cereals (n = 66) and vineyard (n = 68) crops, or from urban area (n = 36). we used cellulose wipes moistened with isopropanol and polypropylene dust traps to collect recent (7 and 30 days, respectively) and settled dust (> 6 months). Overall, 125 pesticides and piperonyl butoxide were detected at least once in households, mostly at low prevalence: 97 in recent dust, and 111 in settled dust. In recent dust, the most prevalent compounds were o-phenylphenol (168 households, 70%), pentachlorophenol (86, 36%), and piperonyl butoxide (82, 34%). In addition to agricultural pesticides, we found a high proportion of domestic and banned compounds in recent and settled house dust. Several pesticides were identified in house dust, from different pesticide groups and sources. Our results suggest that domestic usage and persistence of banned pesticides may contribute substantially to indoor pesticide contamination. Graphical abstract 97 pesticides detected in households’ recent indoor dust.
Afficher plus [+] Moins [-]Socio-economic and environmental factors influenced pro-poor growth process: new development triangle
2019
The developmental triangle earlier comprises economic growth, income inequality, and poverty, while in this study, we extended it by incorporating environmental and resource factors, health and education factors, sectoral value added, and some other growth-specific factors for assessing pro-poor growth, by considering Bolivian economy as a case study. The elasticity estimates show that agriculture and industrial sector growth is not pro-poor due to account of high income inequality, while services sector played a vital role in country’s economic development and supports poor livelihood in a country. Energy and environmental resources negatively impact on quality of life of the poor relative to non-poor, which create income differences among them. Health and education expenditures give favors to the poor and supported the notion of pro-poor growth, while country’s per capita income and foreign direct investment inflows increase income inequality that lead towards pro-rich growth. The results conclude that, in general, Bolivian economy growth is fairly unstable, polluted, and unhealthy that biased to the poor relative to non-poor.
Afficher plus [+] Moins [-]Removal of thallium from environmental samples using a raw and chemically modified biosorbent derived from domestic wastes
2019
Because of its high toxicity, thallium (Tl) causes environmental pollution even at very low concentrations. Despite its extremely high environmental risk, limited information about Tl removal from water is present on the literature. This work focused on the use of an eco-friendly and low-cost Ilex paraguariensis (yerba mate) biowaste to remove Tl from environmental water samples. Raw (YM) and L-cysteine chemically modified yerba mate (YM@LC) were used. The effect of pH and biosorbent concentration on the biosorption capacity was studied using an experimental design. The optimal experimental conditions were as follows: YM concentration 0.25 g L⁻¹, pH 6.0, and YM@LC concentration 0.25 g L⁻¹, pH 4.0. Kinetic studies yielded data that were in accordance with pseudo-second-order model. Equilibrium studies were also developed and indicated that the most appropriate model was that of Sips, with a maximum capacity of biosorption at 328 K of 333.4 mg g⁻¹ for YM and 384.4 mg g⁻¹ for YM@LC. The thermodynamic evaluation exhibited an endothermic, spontaneous, and favorable biosorption for both biosorbents. YM and YM@LC showed significant potential for Tl removal from environmental water samples.
Afficher plus [+] Moins [-]Gallic acid protects particulate matter (PM10) triggers cardiac oxidative stress and inflammation causing heart adverse events in rats
2019
Radan, Maryam | Dianat, Mahin | Badavi, Mohammad | Mard, Seyyed Ali | Bayati, Vahid | Goudarzi, Gholamreza
Previous studies have shown that exposure to particulate matter (PM) increased variety of health problems, particularly cardiovascular diseases leading to premature mortality. The cardiac effects of particulate matter containing PM₁₀ include increased infarct size, decreased heart function, and increased arrhythmias in experimental ischemia-reperfusion models in rats. The aim of this study was to evaluate the effects of particles with an aerodynamic diameter smaller than 10 μm (PM₁₀) on isolated-rat heart and also to determine the efficacy of gallic acid (GA) as a preventive agent in oxidative damage. The healthy rats were divided into 8 equal groups which served as, control, GA, PM₁₀ (0.5, 2.5, and 5 mg/kg), and PM₁₀+GA groups. PM₁₀ administered into the lungs via the trachea in two stages with 48-h interval. After all experiments, the electrocardiogram was recorded. Then, the hemodynamic parameters and ventricular arrhythmias in rat isolated-hearts were assessed using Langendorff apparatus and according to the Lambeth conventions. In addition, the inflammation and oxidative stress factors in cardiac tissues were evaluated in all groups. The obtained results showed that the exposure to PM caused to decrease in cardiac hemodynamic and electrocardiogram parameters. Also, in PM₁₀ rat groups, the IL-6, TNF-α, and oxidative stress parameters were increased. Gallic acid preserved the value of cardiac parameters and inflammation in rat hearts. In summary, we added a novel therapeutic effect of gallic acid for cardiac dysfunction induced by particulate matter. These findings could be related to antioxidant and antiinflammation properties and the obtained results suggest that natural antioxidant like gallic acid could be a therapeutic agent in prevention and management of health issues in the polluted areas of the world.
Afficher plus [+] Moins [-]The quantitative assessment of the public excess disease burden advanced by inhalable particulate matter under different air quality standard targets in Tianjin, China
2019
Zeng, Qiang | Ni, Yang | Li, Guoxing | Wang, Dezheng | Li, Pei | Zheng, Wenlong | Wang, Xin | Jiang, Guohong
Currently, the quantitative assessment of the public excess risk for the update of the air quality guidelines only considered the mortality and morbidity without disease burden indicators. To provide evidences for the update of air quality guidelines and the policy analysis of air control, a simple framework to identify the excess disease burden of PM₁₀ was used in this study. Daily data on PM₁₀, meteorological factors, and deaths were collected in this 10-year (2001–2010) time series study in Tianjin, China. The excess disease burden advanced by PM₁₀ was assessed when the PM₁₀ levels exceeded the expected levels. Generalized additive model was used to estimate the associations of PM₁₀ with mortality and years of life lost (YLL). Our study found that the exposure of PM₁₀ was associated with the increasing of mortality and YLL in different diseases. The excess deaths and YLL of different diseases advanced by PM₁₀ when the PM₁₀ levels exceeded the expected levels were high and showed a decreasing trend from 2001 to 2010. The annual deaths and YLL standardized per million population advanced by PM₁₀ when the annual PM₁₀ levels exceeded the China national ambient air quality secondary standard targets (70 μg/m³) and WHO guideline (20 μg/m³) were 126 persons, 2670 person years and 260 persons, 5449 person years, respectively. This study may provide a simple framework to identify the excess disease burden of PM and provide basic and intuitive evidences to update the air quality guidelines. Furthermore, these findings may also provide decisionmakers with intuitive quantitative information for policymaking and emphasize health considerations in air quality policy discussions.
Afficher plus [+] Moins [-]Socio-geographic disparity in cardiorespiratory mortality burden attributable to ambient temperature in the United States
2019
Zhang, Yunquan | Xiang, Qianqian | Yu, Yong | Zhan, Zhiying | Hu, Kejia | Ding, Zan
Compared with relative risk, attributable fraction (AF) is more informative when assessing the mortality burden due to some environmental exposures (e.g., ambient temperature). Up to date, however, available AF-based evidence linking temperature with mortality has been very sparse regionally and nationally, even for the leading mortality types such as cardiorespiratory deaths. This study aimed to quantify national and regional burden of cardiorespiratory mortality (CRM) attributable to ambient temperature in the USA, and to explore potential socioeconomic and demographic sources of spatial heterogeneity between communities. Daily CRM and weather data during 1987–2000 for 106 urban communities across the mainland of USA were acquired from the publicly available National Morbidity, Mortality and Air Pollution Study (NMMAPS). We did the data analysis using a three-stage analytic approach. We first applied quasi-Poisson regression incorporated with distributed lag nonlinear model to estimate community-specific temperature-CRM associations, then pooled these associations at the regional and national level through a multivariate meta-analysis, and finally estimated the temperature-AF of CRM and performed subgroup analyses stratified by community-level characteristics. Both low and high temperatures increased short-term CRM risk, while temperature-CRM associations varied by regions. Nationally, the fraction of cardiorespiratory deaths caused by the total non-optimum, low, and high temperatures was 7.58% (95% empirical confidence interval, 6.68–8.31%), 7.15% (6.31–7.85%), and 0.43% (0.37–0.46%), respectively. Greater temperature-AF was identified in two northern regions (i.e., Industrial Midwest and North East) and communities with lower temperature and longitude, higher latitude, and moderate humidity. Additionally, higher vulnerability appeared in locations with higher urbanization level, more aging population, less White race, and lower socioeconomic status. Ambient temperature may be responsible for a large fraction of cardiorespiratory deaths. Also, temperature-AF of CRM varied considerably by geographical and climatological factors, as well as community-level disparity in socioeconomic status.
Afficher plus [+] Moins [-]The role of surface hydroxyl concentration on calcinated alumina in catalytic ozonation
2019
Li, Yu | Xu, Jie | Qian, Mengqian | Yu, Jie | Pan, Jian | Guan, Baohong
Alumina has been used as a catalyst for ozonation, surface hydroxyl on which is regarded as the active center for ozone attack, but the influences of hydroxyl generation are still vague. Here, we prepared alumina with different hydroxyl concentrations by adjusting calcination temperatures, of which the catalytic activity was evaluated with the mineralization degree of phenol, and then revealed the active sites of hydroxyl generation with characterization of XRD, Py-IR, and NH₃-TPD. The results show that the greater the hydroxyl concentration, the higher the catalytic activity, demonstrating that surface hydroxyl contributes to its catalytic activity. The effect of calcination temperatures on hydroxyl concentration and catalytic activity is in accordance with the amount of weak Lewis acid sites on the surface of alumina, illustrating the surface hydroxyl derived from the decomposition of water adsorbed on weak Lewis acid sites. However, the catalytic performance of the alumina decreases slowly in a long-term reaction owing to the active center reduction resulted from the coverage by organic acids from phenol degradation. The present work reveals the influences of hydroxyl generation which are beneficial for adjusting surface hydroxyl regarded as active site for ozone attack and the reason of catalyst deactivation, which provides guideline for the rational design of catalyst.
Afficher plus [+] Moins [-]Histopathological effects in gills and liver of Sparus aurata following acute and chronic exposures to erythromycin and oxytetracycline
2019
Rodrigues, Sara | Antunes, Sara C. | Nunes, Bruno | Correia, Alberto Teodorico
Due to their worldwide use and environmental persistence, antibiotics are frequently detected in various aquatic compartments. Their toxic properties raise environmental concerns to non-target organisms. Histopathology data is frequently applied in ecotoxicology studies to assess the effects of different classes of environmental stressors in fish, including antibiotics. Tissue alterations in gills and liver of gilthead seabream (Sparus aurata) individuals acutely (96 h) and chronically (28 days) exposed to environmentally relevant concentrations of the antibiotics erythromycin (ERY: 0.0002–200 μg/L) and oxytetracycline (OTC: 0.0004–400 μg/L), including a control non-exposed group, were evaluated. Several disorders (circulatory, regressive, progressive, and inflammatory) were observed in both organs of all exposed animals. The hereby obtained data showed a higher and significant increase in gill histopathological index of organisms acutely exposed to ERY and of those chronically exposed to OTC. In terms of categorical lesions, only a significant increase of regressive and progressive alterations occurred in gills after chronic exposure to OTC. For the liver, a significant increase in pathological index was also detected, as well as regressive changes, after chronic exposure to OTC. Furthermore, the present study indicates that most of the changes observed in gills and liver were of mild to moderate severity, which might be adaptive or protective, non-specific, and mostly reversible. Despite being observed, irreversible lesions were not significant in any of the fish organs analyzed. Although there were histological changes, gill apparatus was considered still functionally normal, as well as liver tissue, not supporting the occurrence of severe toxicity. In general, the observed histological changes were not stressor-specific, and toxicological mechanistic explanations for the alterations observed in gills and liver are presented. The obtained data showed that histopathological biomarkers can be successfully applied in ecotoxicological studies, evidencing their relevance, responsivity, and complementarity to other biochemical biomarker-based approaches.
Afficher plus [+] Moins [-]Photocatalytic oxidation of toluene and isopropanol by LaFeO3/black-TiO2
2019
Lee, Yun-En | Chung, Wei-Chieh | Chang, Moo-Been
Large amount of volatile organic compounds (VOCs) are emitted from industrial, mobile, and domestic sources, causing adverse effects on human health and environment. Among VOCs, toluene and isopropanol (IPA) are commonly used as solvent, soldering flux, and spray paint and their emissions need to be reduced. Several VOCs abatement technologies are available to reduce VOC emission and photocatalytic oxidation of VOC is regarded as a viable technique due to its advantage of utilizing solar energy. TiO₂ has been investigated for its oxidation capability toward VOCs because of its good photocatalytic activity. However the utilization is limited to UV due to its wider bandgap; furthermore, its fast recombination rate of electron-hole pair reduces the oxidation rate of VOCs. Black-TiO₂ and perovskite-type photocatalyst such as LaFeO₃ can be applied to enhance photocatalytic activity due to narrower bandgap and longer electron-hole pair lifetime. In this study, black-TiO₂ and LaFeO₃ are prepared and investigated for their photocatalytic oxidation rates toward toluene and IPA. Results show that toluene removals achieved with black-TiO₂ and LaFeO₃ are 89% and 98% while IPA removals are 90% and 94%, respectively. Both photocatalysts show better photocatalytic activity than TiO₂ and good absorption capability toward visible light. Graphical abstract
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