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Survey of phthalates, alkylphenols, bisphenol A and herbicides in Spanish source waters intended for bottling 全文
2012
Bono-Blay, Francisco | Guart, Albert | de la Fuente, Boris | Pedemonte, Marta | Pastor, Maria Cinta | Borrell, Antonio | Lacorte, Silvia
BACKGROUND, AIM AND SCOPE: Groundwaters and source waters are exposed to environmental pollution due to agricultural and industrial activities that can enhance the leaching of organic contaminants. Pesticides are among the most widely studied compounds in groundwater, but little information is available on the presence of phthalates, alkylphenols and bisphenol A. These compounds are used in pesticide formulations and represent an emerging family of contaminants due to their widespread environmental presence and endocrine-disrupting properties. Knowledge on the occurrence of contaminants in source waters intended for bottling is important for sanitary and regulatory purposes. So the aim of the present study was to evaluate the presence of phthalates, alkylphenols, triazines, chloroacetamides and bisphenol A throughout 131 Spanish water sources intended for bottling. Waters studied were spring waters and boreholes which have a protection diameter to minimize environmental contamination. MATERIALS AND METHODS: Waters were solid-phase extracted (SPE) and analysed by gas chromatography coupled to mass spectrometry (GC-MS). Quality control analysis comprising recovery studies, blank analysis and limits of detection were performed. RESULTS AND DISCUSSION: Using SPE and GC-MS, the 21 target compounds were satisfactorily recovered (77–124 %) and limits of quantification were between 0.0004 and 0.029 μg/L for pesticides, while for alkylphenols, bisphenol A and phthalates the limits of quantification were from 0.0018 μg/L for octylphenol to 0.970 μg/L for bis(2-ethylhexyl) phthalate. Among the 21 compounds analysed, only 9 were detected at levels between 0.002 and 1.115 μg/L. Compounds identified were triazine herbicides, alkylphenols, bisphenol A and two phthalates. Spring waters or shallow boreholes were the sites more vulnerable to contaminants. Eighty-five percent of the samples did not contain any of the target compounds. CONCLUSIONS: Target compounds were detected in a very low concentration and only in very few samples. This indicates the good quality of source waters intended for bottling and the effectiveness of the protection measures adopted in Spain. None of the samples analysed exceeded the maximum legislated levels for drinking water both in Spain and in the European Union.
显示更多 [+] 显示较少 [-]Biomonitoring the genotoxic effects of pollutants on Tradescantia pallida (Rose) D.R. Hunt in Dourados, Brazil 全文
2012
Crispim, Bruno do Amaral | Vaini, Jussara Oliveira | Grisolia, Alexeia Barufatti | Teixeira, Tatiane Zaratini | Mussury, Rosilda Mara | Seno, Leonardo Oliveira
PURPOSE: This study aimed to associate the intensity of vehicular traffic in the city of Dourados (Mato Grosso do Sul State, Brazil) with mutagenic effects and alterations in leaf physiology as measured by the quantity of micronuclei and the leaf surface parameters of Tradescantia pallida. METHODS: Five collections of inflorescences were undertaken for 24 weeks to determine the quantities of micronuclei using the Tradescantia Micronuclei (Trad-MCN) bioassay. Leaf surface parameters, including stomatal index (SI), stomatal density, and the size of the stomatal ostiole opening size (SO), were evaluated in addition to Trad-MCN. Collections were made at four sampling points with different vehicular traffic intensities. Statistical analyses were performed with SAS software using the Tukey’s and Kruskal–Wallis test. Additionally, associations of the characteristics were verified using Pearson’s simple correlation analysis. RESULTS: Significant effects were observed with the Trad-MCN bioassay (p < 0.01) that were related to the collection period and location, as well as significant differences (p < 0.05) for the effects of the collection points using the Kruskal–Wallis test. In general, the locations with greatest vehicular traffic had plants with the greatest stomatal density values. The characteristics SI and SO did not demonstrate significant differences (p > 0.05) in relation to the collection sites. The simple correlation analysis demonstrated a negative association (−0.65) between SI and Trad-MCN (p < 0.05). CONCLUSION: Plants growing in localities with more intense vehicular traffic had greater quantities of micronuclei as well as higher frequencies and average numbers of stomata than localities with less traffic, indicating the presence of atmospheric contaminants that damaged their DNA.
显示更多 [+] 显示较少 [-]A tiered ecological risk assessment of three chlorophenols in Chinese surface waters 全文
2012
Jin, Xiaowei | Gao, Jijun | Zha, Jinmiao | Xu, Yiping | Wang, Zijian | Giesy, John P. | Richardson, Kristine L.
INTRODUCTION: The ecological risks posed by three chlorophenols (CPs), 2,4-dichlorophenol (2,4-DCP), 2,4,6-trichlorophenol (2,4,6-TCP), and pentachlorophenol (PCP) in Chinese surface waters were assessed. MATERIALS AND METHODS: This was achieved by applying a tiered ecological risk assessment (ERA) approach ranging from deterministic methods to probabilistic options to measured concentrations of CPs in surface water of seven major watersheds and three drainage regions in China and the chronic toxicity data for indigenous Chinese species. RESULTS AND DISCUSSION: The results show that the risks of three chlorophenols are ranked PCP>2,4-DCP≈2,4,6-TCP. PCP posed little ecological risk while 2,4-DCP and 2,4,6-TCP posed negligible or de minimis risk in Chinese surface water. However, the risks varied with different river basins, for example, PCP posed some ecological risk in the Yangtze, Huaihe, and Pearl Rivers. The magnitude of 2,4-DCP and 2,4,6-TCP pollution in North China was more serious than that in South China. CONCLUSION: The probabilistic risk assessment approach, which can provide more information for risk managers and decision makers, was favored over the screening-level single-value estimate method. However, the results from all tiers of the ERA methods in the framework were consistent with each other.
显示更多 [+] 显示较少 [-]Oxidative stress and detoxification biomarker responses in aquatic freshwater vertebrates exposed to microcystins and cyanobacterial biomass 全文
2012
Paskerová, Hana | Hilscherová, Klára | Bláha, Luděk
Cyanobacterial blooms represent a serious threat to the aquatic environment. Among other effects, biochemical markers have been studied in aquatic vertebrates after exposures to toxic cyanobacteria. Some parameters such as protein phosphatases may serve as selective markers of exposure to microcystins, but under natural conditions, fish are exposed to complex mixtures, which affect the overall biomarker response. This review aims to provide a critical summary of biomarker responses in aquatic vertebrates (mostly fish) to toxic cyanobacteria with a special focus on detoxification and oxidative stress. Detoxification biomarkers such as glutathione (GSH) and glutathione-S-transferase (GST) showed very high variability with poor general trends. Often, stimulations and/or inhibitions and/or no effects at GSH or GST have been reported, even within a single study, depending on many variables, including time, dose, tissue, species, etc. Most of the oxidative stress biomarkers (e.g., superoxide dismutase, catalase, glutathione peroxidase, and glutathione reductase) provided more consistent responses, but only lipid peroxidation (LPO) seemed to fulfill the criteria needed for biomarkers, i.e., a sufficiently long half-life and systematic response. Indeed, reviewed papers demonstrated that toxic cyanobacteria systematically elevate levels of LPO, which indicates the important role of oxidative damage in cyanobacterial toxicity. In summary, the measurement of biochemical changes under laboratory conditions may provide information on the mode of toxic action. However, comparison of different studies is very difficult, and the practical use of detoxification or oxidative stress biomarkers as diagnostic tools or early warnings of cyanobacterial toxicity is questionable.
显示更多 [+] 显示较少 [-]Predicting regional space–time variation of PM2.5 with land-use regression model and MODIS data 全文
2012
Mao, Liang | Qiu, Youliang | Kusano, Claudia | Xu, Xiaohui
PURPOSE: Existing land-use regression (LUR) models use land use/cover, population, and traffic information to predict long-term intra-urban variation of air pollution. These models are limited to explaining spatial variation of air pollutants, and few of them are capable of addressing temporal variability. This article proposes a space–time LUR model at a regional scale by incorporating aerosol optical depth (AOD) data from the Moderate Resolution Imaging Spectroradiometer (MODIS). METHODS: A multivariate regression model was established to predict the distribution of particle matters less than 2.5 μm in aerodynamic diameter (PM2.5) in Florida, USA. Monthly PM2.5 averages at 34 monitoring sites in the year 2005 were used as the dependent variable, while independent variables include land-use patterns, population, traffic, and topographic characteristics. In addition, a monthly AOD variable derived from the MODIS data was integrated into the regression as a space–time predictor. Cross-validation procedures were conducted to validate this AOD-enhanced LUR model. RESULTS: The final regression model yields a coefficient of determination (R 2) of 0.63, which is comparable to other studies that employ aerodynamic/meteorological models. The cross validation indicated a good agreement between the observed and predicted PM2.5 with a mean residual of 0.02 μg/m3. The distance to heavy-traffic roads is negatively associated with the concentrations of PM2.5, while agricultural land use is positively correlated. PM2.5 tends to concentrate in high-latitude areas of Florida and during summer/fall seasons. The monthly AOD has a significant contribution to explaining the variation of PM2.5 and remarkably enhances the model performance. CONCLUSIONS: This research is the first attempt to improve current LUR models by integrating remote sensing technologies. The integrative model approach offers an effective means to estimate air pollution over time and space, and could be an alternative to the classic meteorological approach. The model results would provide adequate measurements for epidemiological studies, particularly for chronic health effects in large populations.
显示更多 [+] 显示较少 [-]Isolation of a novel Pseudomonas sp from soil that can efficiently degrade polyethylene succinate 全文
2012
Tribedi, Prosun | Sarkar, Subhasis | Mukherjee, Koushik | Sil, Alok K.
PURPOSE: Polyethylene succinate (PES) is a biodegradable synthetic polymer and therefore widely used as a base material in plastic industry to circumvent the environmental problems related with the non-biodegradability of other polymers like polyethylene. Till date only few organisms have been reported to have the ability to degrade PES. Therefore for better management of PES-related environmental waste, the present study is targeted towards isolating mesophilic organism(s) capable of more efficient degradation of PES. RESULTS: Strain AKS2 was isolated from soil based on survival on a selection plate wherein PES was used as sole carbon source. Ribotyping and biochemical tests revealed that AKS2 is a new strain of Pseudomonas. Scanning electron and atomic force microscopic analysis of the PES films obtained after incubation with AKS2 confirmed PES-degradation ability of AKS2, wherein an alteration in surface topology was observed. The kinetics of PES weight loss showed that AKS2 degrades PES maximally during its logarithmic growth phase at a rate of 1.65 mg/day. This degradation is mediated by esterase activity and may also involve cell-surface hydrophobicity. It has also been observed that AKS2 is able to degrade PES considerably even in the presence of glucose, which is likely to increase the bioremediation potential of this isolate. CONCLUSION: A new strain of Pseudomonas has been isolated from soil that is able to adhere to PES and degrade this polymer efficiently. This organism has the potential to be implemented as a useful tool for bioremediation of PES-derived materials.
显示更多 [+] 显示较少 [-]Acute and chronic toxicity of benzotriazoles to aquatic organisms 全文
2012
Seeland, Anne | Oetken, Matthias | Kiss, Aliz | Fries, Elke | Oehlmann, Jörg
PURPOSE: Resulting from their intensive use as corrosion inhibitors in aircraft deicing and anti-icing fluids (ADAF) and for silver protection in dishwasher detergents benzotriazoles (BTs) are widespread in European surface waters. The current study aimed on an ecotoxicological characterization of 1H-benzotriazole (1H-BT) and 5-methyl-1H-benzotriazole (5MBT). METHODS: Acute and chronic OECD guideline tests were conducted with primary producers (Desmodesmus subspicatus, Lemna minor) and two daphnia species (Daphnia magna, Daphnia galeata) to characterize the hazard of these chemicals. Additionally, the estrogenic activity of both BTs was analyzed in vitro using a recombinant yeast estrogen screen (YES). RESULTS: Both BTs revealed significant effects in acute and chronic experiments, but exhibited no estrogenic activity in the YES. The algal growth test displayed an inhibited cell number increase with effect concentration (EC) values of EC10 1.18 and 2.86 mg l-1 for 1H-BT and 5MBT, respectively. In the Lemna test, EC10 values were 3.94 mg l-1 (1H-BT) and 2.11 mg l-1 (5MBT). D. magna was also affected with EC50 (48 h) values of 107 mg l-1 for 1H-BT and 51.6 mg l-1 for 5MBT. D. galeata was more sensitive with an EC50 (48 h) of 14.7 mg 1H-BT l-1 and 8.13 mg 5MBT l-1. In the 21-day reproduction tests with D. magna, the EC10 for 5MBT was 5.93 mg l-1 while 1H-BT showed no adverse effects. D. galeata turned out to be more sensitive in the chronic study with EC10 values of 0.97 mg l-1 for 1H-BT and 0.40 mg l-1 for 5 MBT. CONCLUSION: Because BTs are regularly found in the aquatic environment at lower μg l-1 concentrations reflecting their persistence and poor elimination during wastewater treatment processes, a preliminary risk assessment was conducted. There is little indication that BTs pose a risk for aquatic ecosystems at current exposure levels during most of the year. However, it cannot be excluded that in winter with a higher usage of ADAFs environmental concentrations may well exceed the level that is considered safe for aquatic organisms.
显示更多 [+] 显示较少 [-]Characteristics of precipitation chemistry at Lushan Mountain, East China: 1992–2009 全文
2012
Li, Yi | Tang, Jie | Yu, Xiaolan | Xu, Xiaobin | Cheng, Hongbing | Wang, Shufeng
INTRODUCTION: Trends in precipitation pH and conductivity during 1992–2009, and in ionic compositions from January 2007 to June 2009, are reported from Lushan Mountain, one of the highest mountains in mid-east China. Annual mean pH was in the range of 4.35–5.01 and showed a statistically very significant (P < 0.01) decreasing trend with time. Annual mean conductivity showed a statistically significant (P < 0.05) increasing trend, although this was not the case for non-H conductivity. Increasing rainwater acidity was mainly caused by increasing amounts of acid substances entering the rain. The trends in precipitation pH and conductivity were directly associated with energy consumption. RESULTS AND DISCUSSIONS: Over the period of study, Lushan Mountain received more rainfall in spring and summer. The pH values varied seasonally with winter minima. The winter multiyear seasonal mean pH was 4.35. The corresponding summer value was 4.88. SO 4 2− and NO 3 − were the main anions, and NH 4 + and Ca2+ the main cations. The anion to cation ratio was 0.8–1.0, and that of [SO 4 2− ] to [NO 3 − ] was 2.4-3.0, much lower than that of the 1980s. However, sulfuric acid was still the main acid present. The ratio of [NH 4 + ] to [Ca2+] was about 1.0, suggesting that these two alkaline substances provided close acid neutralizing capacity. The ratio of [Cl−] to [Na+] was about 0.67, somewhat lower than that of natural precipitation. CONCLUSIONS: Ionic composition varied seasonally and was closely correlated to the amounts of rainfall and pollution. Trajectory analyses showed that the trajectories to Lushan Mountain could be classified in six clusters and trajectories originating from the South Sea and the areas surrounding Lushan Mountain had the greatest impacts on precipitation chemistry.
显示更多 [+] 显示较少 [-]Biodegradation of high molecular weight PAHs using isolated yeast mixtures: application of meta-genomic methods for community structure analyses 全文
2012
Hesham, Abd El-Latif | K̲h̲ān, Sardār | Tao, Yu | Li, Dong | Zhang, Yu | Yang, Min
Bioaugmentation for the removal of polyaromatic hydrocarbons (PAHs) from wastewater using bacteria and yeasts is considered environment-friendly and a cost-effective technique. The effectiveness of this biodegradation system depends on the stability of inoculated microorganisms and the availability of nutrients. This study is aimed to investigate the removal of high molecular weight (HMW)-PAHs from biologically treated produced water using different biological systems. Three systems, inoculated with activated sludge (AS), the mixture of five yeast strains (MY), and the mixture of AS and the five yeast strains (SY), respectively, were constructed, and their performance for the removal of HMW-PAHs was compared over 10 weeks. The effluent of the biologically treated produced water from an oilfield was used as the influent after chrysene and benzo(a)pyrene were spiked as HMW-PAHs. Polymerase chain reaction-based denaturing gradient gel electrophoresis (PCR-DGGE) and fluorescent in situ hybridization (FISH) techniques were used to examine the changes in the structures and abundances of the bacterial and yeast communities in these three systems. Only SY and MY systems were capable to remove chrysene (90.7 % and 98.5 %, respectively) and benzo(a)pyrene (80.7 % and 95.2 %, respectively). PCR-DGGE analysis confirmed that all of the five yeast strains inoculated remained in the SY and MY systems, while FISH results showed that the relative abundance of yeast in the SY and MY systems (10.6 % to 21.9 %, respectively) were significantly higher than AS system (2.3 % to 7.8 %, respectively). The relative abundances of the catechol 2,3-dioxygenase (C23O) indicated that the copy number ratios of benzene ring cleavage gene C23O in the yeast amended systems were much higher than that in the AS system. In this study, all of the three systems were effective in removing the low molecular weight (LMW)-PAHs, while HMW-PAHs including chrysene and benzo(a)pyrene were efficiently removed by MY and SY systems, not by AS system. The high HMW-PAHs removal in the MY and SY bioaugmentation systems possibly attributed to the inoculation of the mixed yeast culture. By combining the PCR-DGGE results with the FISH analyses, it was found that yeast probably consisting mainly of the five inoculated strains inhabited in the two bioaugmentation systems as a dominant population. The relatively higher performance of the SY system might be attributed to the suspended growth type which permitted a more efficient contact between microbial cells and contaminants. The bioaugmentation systems (SY and MY) were successfully established by inoculating with five nonindigenous yeast strains and demonstrated high performance in removal of HMW-PAHs.
显示更多 [+] 显示较少 [-]The Yangtze-Hydro Project: a Chinese–German environmental program 全文
2012
Bergmann, A. | Bi, Y. | Chen, L. | Floehr, T. | Henkelmann, B. | Holbach, A. | Hollert, H. | Hu, W. | Kranzioch, I. | Klumpp, E. | Küppers, S. | Norra, S. | Ottermanns, R. | Pfister, G. | Roß-Nickoll, M. | Schäffer, A. | Schleicher, N. | Schmidt, B. | Scholz-Starke, B. | Schramm, K.-W. | Subklew, G. | Tiehm, A. | Temoka, C. | Wang, J. | Westrich, B. | Wilken, R.-D. | Wolf, A. | Xiang, X. | Yuan, Y.
Water of good quality is one of the basic needs of human life. Worldwide, great efforts are being undertaken for an assured water supply. In this respect, one of the largest water technology projects worldwide is the Yangtze Three Gorges Dam in China. There is a need for extensive scientific and technical understanding of the challenges arising from this large hydrological engineering project. German and Chinese groups from various scientific fields are collaborating to provide knowledge for the sustainable management of the reservoir. In this project description, the Yangtze Three Gorges Dam Project, its goals and challenges, are described in brief, and the contributions of the German research projects are presented.
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