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Microbial transformation of synthetic estrogen 17α-ethinylestradiol
2009
Cajthaml, Tomáš | Křesinová, Zdena | Svobodová, Kateřina | Sigler, Karei | Řezanka, Tomáš
Natural estrogens such as estrone, 17β-estradiol, estriol, and the particularly recalcitrant synthetic estrogen 17α-ethinylestradiol used as oral contraceptive, accumulate in the environment and may give rise to health problems. The processes participating in their removal from soil, wastewater, water-sediments, groundwater-aquifer material, and wastewater or sewage treatment plant effluents may involve the action of bacterial and microbial consortia, and in some cases fungi and algae. This review discusses the different efficiencies of bacterial degradation of 17α-ethinylestradiol under aerobic and anaerobic conditions, the role of sulfate-, nitrate-, and iron-reducing conditions in anaerobic degradation, and the role of sorption. The participation of autotrophic ammonia oxidizing bacteria and heterotrophic bacteria in cometabolic degradation of estrogens, the estrogen-degrading action of ligninolytic fungi and their extracellular enzymes (lignin peroxidase, manganese-dependent peroxidase, versatile peroxidase, laccase), and of algae are discussed in detail. Current knowledge of 17α-ethinylestradiol microbial transformation is summarized.
Afficher plus [+] Moins [-]Submerged Membrane System with Biofilter as a Treatment to Rainwater
2009
Areerachakul, N | Kitiphatmontree, M | Kandasamy, J | Kus, B | Duangduen, C | Pivsa-Art, S | Vigneswaran, S
Rainwater has been used as drinking water in Thailand for centuries especially in the rural parts and is accepted as an important water resource. From past to present, the quality of rainwater has changed with the landuse of the landscape, and its water quality is influenced by a diverse range of conditions such as the management of pollutant sources, the catchment condition, wind and meteorological conditions, and the location of rainwater collection points. In this study, the quality of rainwater collected off roofs at several locations was examined. Granular activated carbon (GAC) filtration was used as a pretreatment to microfiltration (MF) to remove the dissolved organic matter (DOC). After an initial adsorption period, the biofilm that formed on the GAC (biofilter) was found to remove DOC by up to 40%, 35%, and 15% for bed filter depths of 15, 10, and 5 cm, respectively. Biofilters also removed nitrate and phosphate by more than 80% and 35%. The hollow fiber membrane microfiltration with pore size of 0.1 μm was used to treat the effluent from biofiltration to remove the microorganisms/pathogens in the rainwater. Although there was no significant additional removal of DOC by MF, the biofilter removed all microorganisms. The use of biofilters as pretreatment to MF/UF could remove a higher amount of DOC, remove microorganisms, increase the membrane treatment efficiency, and reduce membrane fouling.
Afficher plus [+] Moins [-]Establishment of a constructed wetland in extreme dryland
2009
Tencer, Yoram | Idan, Gil | Strom, Marjorie | Nusinow, Uri | Banet, Dorit | Cohen, Eli | Schröder, Peter | Shelef, Oren | Rachmilevitch, Shimon | Soares, Ines | Gross, Amit | Golan-Goldhirsh, Avi
Background, aim, and scope The project was set to construct an extensive wetland in the southernmost region of Israel at Kibbutz Neot Smadar (30°02′45″ N and 35°01′19″ E). The results of the first period of monitoring, summary, and perspectives are presented. The constructed wetland (CW) was built and the subsequent monitoring performed in the framework of the Southern Arava Sustainable Waste Management Plan, funded by the EU LIFE Fund. The specific aims were: (1) To end current sewage disposal and pollution of the ground, the aquifer, and the dry river bed (wadi) paths by biologically treating the sewage as part of the creation of a sustainable wetland ecosystem. (2) Serve as an example of CW in the Negev highlands and the Arava Valley climates for neighboring communities and as a test ground for plants and building methods appropriate to hyper arid climate. (3) Serve as an educational resource and tourist attraction for groups to learn about water reuse, recycling, local wildlife and migrating birds, including serving the heart of a planned Ecological-Educational Bird Park. This report is intended to allow others who are planning similar systems in hyper arid climates to learn from our experience. Materials and methods The project is located in an extreme arid desert with less than 40 mm of rain annually and temperature ranges of −5°C to +42°C. The site receives 165-185 m³ of municipal and agricultural wastes daily, including cowshed and goat wastes and winery outflow. Results The CW establishment at Neot Smadar was completed in October 2006. For 8 months, clean water flowed through the system while the plants were taking root. In June 2007, the wetland was connected to the oxidation pond and full operation began. Because of seepage and evaporation, during the first several months, the water level was not high enough to allow free flow from one bed to the next. To bed A, the water was pumped periodically from the oxidation pond (Fig. 1) and from there flowed by gravitation through the rest of the system. The initial results of the monitoring are promising. In nearly all measurements, the system succeeded as expected to reduce levels of contaminants at least to the level acceptable for irrigating fruit trees and often to the level of unlimited irrigation. The introduction of the plants in the system and their physiological performance were evaluated and were found to correlate well to the quality of water in the various beds. Discussion It should be said at the outset that evaluation of the performance of a CW system is a long-term process. Thus, the main aim of this report is to present the problems, difficulties, preliminary results, and concepts concerned with the first stage of establishment of CW in an extremely dry region. Conclusions The CW system was designed to dispose of municipal and agricultural wastes in a way that not merely reduces pollution, but adds to environmental quality by creating accessible parkland for local residents and tourists. Several factors affected the performance of the system at the initial stages of operation: ecological balance between microbes and plants, big seasonal variations, seepage and evaporation reduced the flow in the initial operation of the system. Despite the initial difficulties, the quality of water coming out the system is acceptable for irrigation. Recommendations and perspectives The CW can function well under extreme dryland conditions. The oxidation pond was the major source of evaporation and bad odors. Therefore, alternatives to the oxidation pond are needed. Cost effectiveness of the system still has to be evaluated systematically.
Afficher plus [+] Moins [-]The formation and fate of chlorinated organic substances in temperate and boreal forest soils
2009
Clarke, Nicholas | Fuksová, Květoslava | Gryndler, Milan | Lachmanová, Zora | Liste, Hans-Holger | Rohlenová, Jana | Schroll, Reiner | Schröder, Peter | Matucha, Miroslav
Background, aim and scope Chlorine is an abundant element, commonly occurring in nature either as chloride ions or as chlorinated organic compounds (OCls). Chlorinated organic substances were long considered purely anthropogenic products; however, they are, in addition, a commonly occurring and important part of natural ecosystems. Formation of OCls may affect the degradation of soil organic matter (SOM) and thus the carbon cycle with implications for the ability of forest soils to sequester carbon, whilst the occurrence of potentially toxic OCls in groundwater aquifers is of concern with regard to water quality. It is thus important to understand the biogeochemical cycle of chlorine, both inorganic and organic, to get information about the relevant processes in the forest ecosystem and the effects on these from human activities, including forestry practices. A survey is given of processes in the soil of temperate and boreal forests, predominantly in Europe, including the participation of chlorine, and gaps in knowledge and the need for further work are discussed. Results Chlorine is present as chloride ion and/or OCls in all compartments of temperate and boreal forest ecosystems. It contributes to the degradation of SOM, thus also affecting carbon sequestration in the forest soil. The most important source of chloride to coastal forest ecosystems is sea salt deposition, and volcanoes and coal burning can also be important sources. Locally, de-icing salt can be an important chloride input near major roads. In addition, anthropogenic sources of OCls are manifold. However, results also indicate the formation of chlorinated organics by microorganisms as an important source, together with natural abiotic formation. In fact, the soil pool of OCls seems to be a result of the balance between chlorination and degradation processes. Ecologically, organochlorines may function as antibiotics, signal substances and energy equivalents, in descending order of significance. Forest management practices can affect the chlorine cycle, although little is at present known about how. Discussion The present data on the apparently considerable size of the pool of OCls indicate its importance for the functioning of the forest soil system and its stability, but factors controlling their formation, degradation and transport are not clearly understood. It would be useful to estimate the significance and rates of key processes to be able to judge the importance of OCls in SOM and litter degradation. Effects of forest management processes affecting SOM and chloride deposition are likely to affect OCls as well. Further standardisation and harmonisation of sampling and analytical procedures is necessary. Conclusions and perspectives More work is necessary in order to understand and, if necessary, develop strategies for mitigating the environmental impact of OCls in temperate and boreal forest soils. This includes both intensified research, especially to understand the key processes of formation and degradation of chlorinated compounds, and monitoring of the substances in question in forest ecosystems. It is also important to understand the effect of various forest management techniques on OCls, as management can be used to produce desired effects.
Afficher plus [+] Moins [-]Assessment of successful experiments and limitations of phytotechnologies: contaminant uptake, detoxification and sequestration, and consequences for food safety
2009
Mench, Michel | Schwitzguébel, Jean-Paul | Schroeder, Peter | Bert, Valérie | Gawronski, Stanislaw | Gupta, Satish
Purpose The term “phytotechnologies” refers to the application of science and engineering to provide solutions involving plants, including phytoremediation options using plants and associated microbes to remediate environmental compartments contaminated by trace elements (TE) and organic xenobiotics (OX). An extended knowledge of the uptake, translocation, storage, and detoxification mechanisms in plants, of the interactions with microorganisms, and of the use of “omic” technologies (functional genomics, proteomics, and metabolomics), combined with genetic analysis and plant improvement, is essential to understand the fate of contaminants in plants and food, nonfood and technical crops. The integration of physicochemical and biological understanding allows the optimization of these properties of plants, making phytotechnologies more economically and socially attractive, decreasing the level and transfer of contaminants along the food chain and augmenting the content of essential minerals in food crops. This review will disseminate experience gained between 2004 and 2009 by three working groups of COST Action 859 on the uptake, detoxification, and sequestration of pollutants by plants and consequences for food safety. Gaps between scientific approaches and lack of understanding are examined to suggest further research and to clarify the current state-of-the-art for potential end-users of such green options. Conclusion and perspectives Phytotechnologies potentially offer efficient and environmentally friendly solutions for cleanup of contaminated soil and water, improvement of food safety, carbon sequestration, and development of renewable energy sources, all of which contribute to sustainable land use management. Information has been gained at more realistic exposure levels mainly on Cd, Zn, Ni, As, polycyclic aromatic hydrocarbons, and herbicides with less on other contaminants. A main goal is a better understanding, at the physiological, biochemical, and molecular levels, of mechanisms and their regulation related to uptake-exclusion, apoplastic barriers, xylem loading, efflux-influx of contaminants, root-to-shoot transfer, concentration and chemical speciation in xylem/phloem, storage, detoxification, and stress tolerance for plants and associated microbes exposed to contaminants (TE and OX). All remain insufficiently understood especially in the case of multiple-element and mixed-mode pollution. Research must extend from model species to plants of economic importance and include interactions between plants and microorganisms. It remains a major challenge to create, develop, and scale up phytotechnologies to market level and to successfully deploy these to ameliorate the environment and human health.
Afficher plus [+] Moins [-]Microbiological groundwater quality of drinking water source Strand and protected aereas [i.e. areas], [in Novi Sad, Serbia] | Mikrobioloski kvalitet podzemne vode izvorista Strand i zone sanitarne zastite [Novi Sad, Srbija]
2009
Petrovic, O. | Knezevic, P. | Simeunovic, J., Prirodno-matematicki fakultet, Novi Sad (Serbia). Departman za biologiju i ekologiju | Ivanovic, D., JKP Vodovod i kanalizacija, Novi Sad (Serbia) | Jokanovic, S., Gradska Uprava za zastitu zivotne sredine, Novi Sad (Serbia)
In the paper is presented the microbiological quality of groundwater of drinking water supply Strand which is important water source for the city of Novi Sad (Serbia). The examinations were carried out using high and low nutritive media. The count of physiological groups, that are relevant from the aspect of organic pollution and phosphatase activity were also monitored. The results indicate potential organical pollution and need for protection of the water supply Strand.
Afficher plus [+] Moins [-]Microbiological study of the Bovan reservoir [Serbia] | Mikrobioloska studija akumulacije Bovan [Srbija]
2009
Radojevic, I., Prirodno-matematicki fakultet, Kragujevac (Serbia) | Roganovic, S., Prirodno-matematicki fakultet, Kragujevac (Serbia) | Comic, Lj., Prirodno-matematicki fakultet, Kragujevac (Serbia) | Ostojic, A., Prirodno-matematicki fakultet, Kragujevac (Serbia)
The Bovan reservoir is built on the river Moravica, near Aleksinac (Serbia), primarily for the purpose of water supply. Investigations were carried out during the period of June 2005 to December 2006, with the aim to determine the quality of water, the composition, spatial and time dynamics of communities of microorganisms. The results showed that according to the total number of bacteria in the water reservoir Bovan fall into the category of clean water by Amrazena (1976). By Kohl (1975), water reservoir Bovan belongs to class 2. Summer-time give maximum water characteristics the 2nd-3rd class. Index T/H varies from category to category moderately contaminated clean water. Values heterotrophs percentage representation in the total number of bacteria indicating the great burden of water organic matter.
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