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1.
Environmental Science and Pollution Research - Acrylamide (AA), an industrial monomer, may cause multi-organ toxicity through induction of oxidative stress and inflammation. The antioxidant...  相似文献   

2.
Environmental Science and Pollution Research - Air particulate matter exposure has been linked to cardiovascular and atherosclerosis as a result of increase oxidative stress and inflammatory...  相似文献   

3.
4.
Environmental Science and Pollution Research - Aluminum, one of the most abundant metallic elements, is known to be toxic to multiple organs including the kidneys. This study aimed to investigate...  相似文献   

5.
A laboratory experiment was carried out to test the efficiency of a bio-mixture made up of pruning residues at two (PR2) and five (PR5) years of composting and wheat straw (STW) in the biological cleaning of water contaminated by different mixtures of fungicides usually employed in vineyards. The experiment was conducted and reproduced at a scale of 1:100 of operating field conditions. Commercial formulates of penconazole (PC), (RS)-1-[2-(2,4-dichlorophenyl)pentyl]-1H-1,2,4-triazole), dimetomorph (DM), (EZ)-4-[3-(4-chlorophenyl)-3-(3,4-dimethoxyphenyl)acryloyl]morpholine), azoxystrobin (AZ), (methyl (E)-2-{2-[6-(2-cyanophenoxy)pyrimidin-4-yloxy]phenyl}-3-methoxyacrylate), iprovalicarb (IP), (isopropyl 2-methyl-1-[(RS)-1-p-tolylethyl]carbamoyl-(S)-propylcarbamate), metalaxyl (MX), (methyl N-(methoxyacetyl)-N-(2,6-xylyl)-DL-alaninate), fludioxonil (FL), (4-(2,2-difluoro-1,3-benzodioxol-4-yl)-1H-pyrrole-3-carbonitrile) and cyprodinil (CY), (4-cyclopropyl-6-methyl-N-phenylpyrimidin-2-amine) were mixed in water and discharged into the bio-mixture following the time schedule of the treatments carried out in the grapevine in real field conditions. At each treatment, contaminated water with fungicides was circulated repeatedly through the bio-mixture to enhance the sorption of fungicides. In fact, it retained them between 98–100% with the exception of MX of which it was able to retain only 90.5%. The adsorption/desorption experiment showed that repeated circulation of water, instead of enhancing MX retention, can easily remove about 30% of MX already adsorbed by the bio-mixture. This finding suggests that water contaminated by very mobile pesticides should be discharged at the end of field treatments without re-circulating the water in order to avoid the release of pesticides weakly adsorbed on the bio-mixture.  相似文献   

6.
Environmental Science and Pollution Research - The degradation efficiencies and pathways of metronidazole (MNZ) and amoxicillin (AMX) in binary mixtures by UV/TiO2 photocatalysis were studied. The...  相似文献   

7.
Results of a fault test performed in the unsaturated zone of Yucca Mountain, Nevada, were analyzed using a three-dimensional numerical model. The fault was explicitly represented as a discrete feature and the surrounding rock was treated as a dual-continuum (fracture-matrix) system. Model calibration against seepage and water-travel-velocity data suggests that lithophysal cavities connected to fractures can considerably enhance the effective fracture porosity and therefore retard water flow in fractures. Comparisons between simulation results and tracer concentration data also indicate that matrix diffusion is an important mechanism for solute transport in unsaturated fractured rock. We found that an increased fault-matrix and fracture-matrix interface areas were needed to match the observed tracer data, which is consistent with previous studies. The study results suggest that the current site-scale model for the unsaturated zone of Yucca Mountain may underestimate radionuclide transport time within the unsaturated zone, because an increased fracture-matrix interface area and the increased effective fracture porosity arising from lithophysal cavities are not considered in the current site-scale model.  相似文献   

8.
The detrainment behaviour of contaminants in the wake of an isolated building was investigated in the field under atmospheric stability conditions ranging from very stable to very unstable. The model building used was a 2 m cube and two orientations were investigated, with the cube either normal or at 45° to the wind. Tracer gas was first entrained into the wake from a source located a short distance upwind of the cube, the gas being released continuously for a limited period in order to fill the wake. Thereafter, the source was switched off, and the concentration (measured using several fast-response gas detectors located in the wake) was observed to decay in an exponential manner. This procedure was repeated in a total of 118 experiments to provide confidence in statistics. The residence time (Td), which is defined as the time it takes for the concentration to decay to 1/e of its original value, was measured. The decay duration (t), which is the time it takes for the gas to become fully detrained from the wake, was found to be greater in stable atmospheric conditions, mainly due to the lower wind speeds and higher concentrations observed under these conditions. However, the non-dimensional residence time (τ) was found to be independent of atmospheric stability. The values of τ for a cube normal (τ=6.2) or at 45° to the flow (τ=9.5) are in very good agreement with values calculated using empirical formulae derived from wind tunnel experiments.  相似文献   

9.
We report on computational fluid dynamics (CFD) predictions of mixing time of a pollutant in an unventilated, mechanically mixed, isothermal room. The study aims to determine: (1) the adequacy of the standard Reynolds Averaged Navier Stokes two-equation (k−) turbulence model for predicting the mixing time under these conditions and (2) the extent to which the mixing time depends on the room airflow, rather than the source location within the room. The CFD simulations modeled the 12 mixing time experiments performed by Drescher et al. (Indoor Air 5 (1995) 204) using a point pulse release in an isothermal, sealed room mechanically mixed with variable power blowers. Predictions of mixing time were found in good agreement with experimental measurements, over an order of magnitude variation in blower power. Additional CFD simulations were performed to investigate the relation between pollutant mixing time and source location. Seventeen source locations and five blower configurations were investigated. Results clearly show large dependence of the mixing time on the room airflow, with some dependence on source location. We further explore dependence of mixing time on the velocity and turbulence intensity at the source location. Implications for positioning air-toxic sensors in rooms are briefly discussed.  相似文献   

10.
Environmental Science and Pollution Research - Pesticides are emergent toxins often identified in aquatic environments. In the present study, microplasma was employed to reduce the pesticide...  相似文献   

11.
Environmental Science and Pollution Research - This study investigates the kinked exponential growth, degree of association, and causation between economic growth, energy consumption, population,...  相似文献   

12.
Thermal conductivity is an important property that governs the behaviour of leaf compost biofilters used in treating gaseous pollutants. Measurements were carried out for the thermal conductivity (K) of 44 samples of leaf compost, covering wide ranges of the volume fractions of water (xi(w)), solids (xi(s)) and air (xi(a)), at 20 degrees C using an unsteady state thermal probe. The results indicated that the compost thermal conductivity increased with an increase in xi(w), with a decrease in xi(a), and with an increase in the degree of saturation (defined as the volumetric fraction of water in the total void space). The predictions from the Woodside-Messmer quadratic parallel (QP) model for the thermal conductivity of leaf compost were higher than the experimental values. A simple linear relationship was developed between the thermal conductivity and the degree of saturation, which provided a satisfactory correlation for the data measured in this study as well as those reported recently for sandy and clay loams.  相似文献   

13.
The possibility to improve atrazine degradation in soils by bioaugmentation was studied. The atrazine-mineralizing strain, Chelatobacter heintzii Cit1, was inoculated in four sterile and four non-sterile soils, at varying inoculum densities. Two soils, which had shown enhanced atrazine mineralization, were used to determine which inoculum density was capable of restoring their original mineralizing capacity after sterilization. The two other soils, with intermediate and low capacity to mineralize atrazine, were used in order to demonstrate that atrazine mineralization in such soils could be improved by inoculation. Mineralization kinetics were fitted using the Gompertz model. In the case of soils adapted to atrazine mineralization, inoculation of C. heintzii did not accelerate the rate of atrazine mineralization, which was essentially performed by the indigenous microflora. However, with soils that did not mineralize atrazine, the introduction of 10(4) cfug(-1) resulted in a 3-fold increase of atrazine mineralization capacity.  相似文献   

14.
Between January 1988 and February 1989, gizzards were collected from 1155 birds from the groups; Anatidae, Charadriidae, Scolopacidae and Rallidae, shot in the Camargue, and examined for the presence of ingested lead shot. Shot was found in nine out of ten Anatidae species, three of 15 Scolopacidae species and all of three Rallidae species. Twenty-seven per cent of Anatidae sampled had ingested shot, 13.8% had one shot present and 6.3% had more than five. Shot ingestion levels ranged from 3-60% of birds examined according to species. The incidence of shot ingestion did not appear to vary seasonally. In Anatidae, a strong interspecific relationship was found between the grit size ingested and susceptibility to ingest shot (r = 0.94). In Scolopacidae, shot ingestion may have been related to grit size ingested, feeding method and bill length. The levels of shot ingestion presented are for most species higher than have been reported elsewhere in the world. This may result from the absence of grit and presence of high shot densities in Camargue marshes.  相似文献   

15.

Rising economic growth in recent ages is the primary concern of most of the countries to enhance the living standard, but the ever-increasing production of economic activities consumes a lot of energy, which leads to a sharp increase in carbon dioxide emissions. Innovation may be a remedy that can help improve energy efficiency, obtain renewable energy, and promote economic growth, thereby protecting the quality of the environment. Therefore, this paper examines the role of innovation and renewable energy consumption in CO2 reduction in OECD countries from 2004 to 2019. By using the two-step system generalized of moment estimator, the results show that economic growth and innovation significantly increase carbon emissions, however the innovation Claudia Curve (ICC) is verified, and the environmental Kuznets curve does not exist. Foreign direct investment has a negative impact on carbon emissions, thus verifying the Pollution Hao hypothesis, whereas renewable energy also improves environmental quality, but the interaction between innovation and renewable energy consumption still increases carbon emissions. Financial development, industrialization, trade, and energy consumption have also been found to be harmful factors of environmental quality. Our findings have considerable policy implications for OECD countries on the improvement of innovation indicators and investment in renewable energy sources to rise environmental quality.

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16.
During Fall 1996, epiphytic lichens were collected along altitudinal sections in two areas of France (the Vosges mountains in the North-East, and the Alps, in Haute-Savoie) in order to verify any geographic distribution of atmospheric metals on a small scale. These lichens have various Pb isotopic compositions (206Pb/207Pb=1.126–1.147) which are correlated with the altitude of sampling. Lichens sampled near valleys display isotopic ratios significantly less radiogenic than those sampled at several hundred to thousand meters of altitude. In the Vosges sections, Pb concentrations and isotopic compositions of lichens may be used to define three zones: (1) valley: Pb-rich and non-radiogenic ratios, (2) transition: low-Pb and intermediate isotopic compositions, (3) mountain: heterogeneous Pb concentrations but more radiogenic and homogeneous Pb isotopic composition. Other metals (Zn, Cu, Cd, As), when normalised one to another, are not fractionated between these zones and display homogeneous relative abundance along the altitudinal sections of both sites. Variation of 206Pb/207Pb ratios with altitude is interpreted in terms of mixing of at least two pollution sources: one being the petrol (leaded and/or unleaded) combustion, and the other being of industrial origin. The latter is characterised by a more radiogenic isotopic composition. The Pb isotopic composition of flue gas residues from different municipal solid waste combustors in the Rhine valley and in other areas of France would suggest that these plants might be an important source of industrial Pb in the atmosphere. If the average industrial Pb in France has a 206Pb/207Pb close to 1.15, between 60 and 80% of the total Pb in lichens from the Rhine valley would come from gasoline combustion, whereas 85–90% of the Pb would have an industrial origin in lichens from higher altitude in the Vosges mountains. Although lichens from the Alps were collected at higher altitude, the percentage of industrial Pb for these lichens would be slightly lower (65%). Major winds and convection winds in the different valleys must then play an important role in term of distribution of atmospheric Pb in function of altitude.  相似文献   

17.

Introduction  

Chlorimuron-ethyl has been widely used for the soybean production of China, but less information is available on the possible risk of long-term application of this herbicide.  相似文献   

18.
The variability of species sensitivity distribution (SSD) due to contaminant bioavailability in soil was explored by using nickel as metal of concern. SSDs of toxicity test results of Avena sativa L. originating from different soils and expressed as total content and available (0.01 M CaCl2) extractable concentration were compared to SSDs for terrestrial plants derived from literature toxicity data. Also the 'free' nickel (Ni2+) concentration was calculated and compared. The results demonstrated that SSDs based on total nickel content highly depend on the experimental conditions set up for toxicity testing (i.e. selected soil and pH value) and thus on metal bioavailability in soil, resulting in an unacceptable uncertainty for ecological risk estimation. The use in SSDs of plant toxicity data expressed as 0.01 M CaCl2 extractable metal strongly reduced the uncertainty in the SSD curve and thus can improve the ERA procedure remarkably by taking bioavailability into account.  相似文献   

19.
Sequential extraction (modified BCR procedure) combined with isotope analysis has been investigated as a tool for assessing mobilisation of lead into streams at an upland catchment in NE Scotland. The maximum lead concentrations (up to 110 mg kg(-1) in air-dried soil) occurred not at the surface but at about 10 cm depth. The lowest (206)Pb/(207)Pb ratios in any profile occurred, with one exception, at 2.5-5 cm depth. In the one exception, closest to the only road in the area, significantly lower (206)Pb/(207)Pb ratios in the surface soil together with much increased chloride concentrations (in comparison to other surface waters) indicated the possible mobilisation of roadside lead and transfer to the stream. The (206)Pb/(207)Pb ratios in extractable fractions tended at depth towards the ratio measured in the residual phase but the ratios in the oxidizable fraction increased to a value higher than that of the residual phase.  相似文献   

20.

Purpose  

Besides classical organic pollutants and pesticides, pharmaceuticals and their residues have nowadays become recognized as relevant environmental contaminants. The risks of these chemicals for aquatic ecosystems are well known, but information about the pharmaca-plant interactions and metabolic pathways is scarce. Therefore, we investigate the process of uptake of acetaminophen (N-Acetyl-4-aminophenol) by Brassica juncea, drug-induced defense responses and detoxification mechanisms in different plant parts.  相似文献   

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