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Environmental Science and Pollution Research - Alkylphenols are industrial pollutants commonly present in wastewater. They are difficult to eliminate by conventional treatment processes, ending up...  相似文献   

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Analyses of commercially available wines suggested non-Brettanomyces sources of 4-ethylphenol and 4-ethylguaiacol. Grapes, enological additions, exposure to plastics, and oak-barrel aging were potential inputs considered. Investigations of whole grape bunch samples from two major red wine Vitis vinifera cultivars (L. cv. Cabernet Franc and Pinot Noir), a commercial mannoprotein additive, and three commercial enological tannin additions indicated they are not likely significant sources of these compounds. Studies on 15 commercial oak barrelled red wines from six Vitis vinifera cultivars (L. cv. Cabernet Franc, Cabernet Sauvignon, Dunkelfelder, Merlot, Pinot Meunier, and Pinot Noir), and a review of volatile phenol extraction from toasted oak wood, suggested that oak-aging may produce concentrations of up to 50 μg L?1 4-ethylphenol and 4-ethylguaiacol. Thus, following potential Brettanomyces-sourced aroma impacts in wine using 4-ethylphenol and/or 4-ethylguaiacol concentrations as proxies should only be considered reliable at analyte levels > 100 μg L?1. A review of worldwide 4-ethylphenol and 4-ethylguaiacol concentrations in wine, consumption patterns, and available toxicological data also suggested that levels of 4-ethylphenol being observed in wines worldwide do not warrant concerns about acute or long-term effects. While little is known about the toxicology of 4-ethylguaiacol, it is unlikely that elevated concentrations will pose any health-related concerns.  相似文献   

4.
Analyses of commercially available wines suggested non-Brettanomyces sources of 4-ethylphenol and 4-ethylguaiacol. Grapes, enological additions, exposure to plastics, and oak-barrel aging were potential inputs considered. Investigations of whole grape bunch samples from two major red wine Vitis vinifera cultivars (L. cv. Cabernet Franc and Pinot Noir), a commercial mannoprotein additive, and three commercial enological tannin additions indicated they are not likely significant sources of these compounds. Studies on 15 commercial oak barrelled red wines from six Vitis vinifera cultivars (L. cv. Cabernet Franc, Cabernet Sauvignon, Dunkelfelder, Merlot, Pinot Meunier, and Pinot Noir), and a review of volatile phenol extraction from toasted oak wood, suggested that oak-aging may produce concentrations of up to 50 microg L(-1) 4-ethylphenol and 4-ethylguaiacol. Thus, following potential Brettanomyces-sourced aroma impacts in wine using 4-ethylphenol and/or 4-ethylguaiacol concentrations as proxies should only be considered reliable at analyte levels>100 microg L(-1). A review of worldwide 4-ethylphenol and 4-ethylguaiacol concentrations in wine, consumption patterns, and available toxicological data also suggested that levels of 4-ethylphenol being observed in wines worldwide do not warrant concerns about acute or long-term effects. While little is known about the toxicology of 4-ethylguaiacol, it is unlikely that elevated concentrations will pose any health-related concerns.  相似文献   

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Surveys of 4-nonylphenols (NOs) and 4-tert-octylphenol (OC) were performed for water and fish samples obtained from eight rivers flowing into Lake Biwa once every two months from April 1998 to March 1999. For water samples, NOs were detected all the year round (0.11-3.08 ng ml(-1)) at high frequency (48/48) in the eight rivers. OC was detected at lower concentrations (ND approximately 0.09 ng ml(-1)) and at lower frequency (23/48). The concentrations of NOs in the river water always showed minimum values at 5-8 degrees C in winter. It was presumed that the formation of NOs by the biotransformation of nonylphenol polyethoxylates decreased much in the sludge treatment of nonionic surfactants at the low temperature (5-8 degrees C) in winter. Average BCF values of NOs and OC in the six kinds of fish were calculated from the field data. The field BCF values of NOs 15-31 in the six kinds of fish were lower than the laboratory BCF values of 167 in Killifish and 282 in Salmon. For OC, the field BCF values 129-297 for the three kinds of fish were nearly equal to the laboratory BCF value, 261, in Killifish.  相似文献   

6.
Bioaccumulation of 4-nonylphenol in marine animals--a re-evaluation   总被引:12,自引:0,他引:12  
The bioaccumulation of 4-nonylphenol (NP) has been studied in shrimps (Crangon grangon L.), mussels (Mytilus edulis L.) and sticklebacks (Gasterosteus aculeatus L.) exposed to (14)C-NP in running seawater. NP was extracted with high recovery from tissues which were pretreated with pancreatic enzymes. The bioconcentration factor determined of NP in fish was 1300 and in mussels, 3400. These values are 5 and 340 times higher, respectively, than values reported earlier.  相似文献   

7.
Burkholderia sp. RKJ 800 utilized 4-chloro-2-aminophenol (4C2AP) as the sole carbon and energy source and degraded it with release of chloride and ammonium ions. The metabolic pathway of degradation of 4C2AP was studied and a novel intermediate, 4-chlorocatechol was identified as a major degradation product of 4C2AP using high-performance liquid chromatography and gas chromatography–mass spectrometry. Enzyme activities for 4C2AP-deaminase and 4-chlorocatechol-1,2-dioxygenase were detected in the crude extracts of the 4C2AP-induced cells of strain RKJ 800. The activity of the 4C2AP-deaminase confirmed the formation of 4-chlorocatechol from 4C2AP and the 4-chlorocatechol-1,2-dioxygenase activity suggested the cleavage of 4-chlorocatechol into 3-chloro-cis,cis-muconate. On the basis of the identified metabolites, we have proposed a novel degradation pathway of 4C2AP for Burkholderia sp. RKJ 800. Furthermore, the potential of Burkholderia sp. RKJ 800 to degrade 4C2AP in soil was also investigated using microcosm studies under laboratory conditions. The results of microcosm studies conclude that Burkholderia sp. RKJ 800 was able to degrade 4C2AP in soil and may be used to remediate 4C2AP-contaminated site. This is the first report of (1) the formation of 4-chlorocatechol and 3-chloro-cis,cis-muconate in the degradation pathway of 4C2AP and (2) bioremediation of 4C2AP by any bacterium.  相似文献   

8.
Biodegradation of 4-nonylphenol in seawater and sediment   总被引:15,自引:0,他引:15  
Biodegradation of 14C-labelled nonylphenol at the concentration 11 microg litre (-1) in seawater has been estimated by collection and quantification of the formed labelled carbon dioxide. Initially degradation was very slow but when the microorganisms had become adapted, after four weeks at 11 degrees C, the degradation rate increased rapidly and after 58 days about 50% of 14C from NP was found in the CO2 fraction. In the presence of sediment the initial degradation rate was high and did not increase after longer incubation. Lack of oxygen reduced the degradation rate by half in the presence of sediment.  相似文献   

9.
This paper reports the reconstruction of the pollution history of 4-tert-octylphenol (OP) and 4-nonylphenol (NP) in the Baltic Sea. Alkylphenols are endocrine-disrupting compound and therefore toxic to aquatic organisms. Sediment cores were collected from regions with relatively stable sedimentation conditions. The cores were dated by the 210Pb method. The OP and NP were determined using HPLC-FL. The highest inventory of these compounds was observed in the Gotland Deep (610 μg m2 of NP and 47 μg m2 of OP) and the lowest—on the slope of the Gdansk Deep (24 μg m2 of NP and 16 μg m2 of OP). Such spatial distribution was probably, among other factors, the result of the uplift of the sea floor. The pollution trends of OP and NP in sediments coincided with the following: (1) the beginnings of eutrophication (1960s/1970s of the twentieth century) and (2) strong increase in the areal extent and volume of hypoxia and anoxia in the Baltic (present century).  相似文献   

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The effects of chronically enhanced (NH(4))(2)SO(4) deposition on ion concentrations in soil solution and ionic fluxes were investigated in a Picea abies plot at Grizedale forest, NW England. Soil cores closed at the base and containing a ceramic suction cup sampler were 'roofed' and watered every 2 weeks with bulk throughfall collected in the field. Treatments consisted of the inclusion of living roots from mature trees in the lysimeters and increasing (NH(4))(2)SO(4) deposition (NS treatment) to ambient + 75 kg N ha(-1) a(-1). Rainfall, throughfall and soil solutions were collected every 2 weeks during 18 months, and analysed for major cations and anions. NO(3)(-) fluxes significantly increased following NS treatment, and were balanced by increased Al(3+) losses. Increased SO(4)(2-) concentrations played a minor role in controlling soil solution cation concentrations. The soil exchange complex was dominated by Al and, during the experimental period, cores of all treatments 'switched' from Ca(2+) to Al(3+) leaching, leading to mean [Formula: see text] molar ratios in soil solution of NS treated cores of 0.24. The experiment confirmed that the most sensitive soils to acidification (through deposition or changing environmental conditions) are those with low base saturation, and with a pH in the lower Ca, or Al buffer ranges.  相似文献   

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Environmental Science and Pollution Research - Biomonitoring studies are important tools to understand the effects of endocrine-disrupting compounds on human health. Up to now, there have been no...  相似文献   

14.
Decomposition of 4-bromobiphenyl in soil mediated by microwave energy   总被引:5,自引:0,他引:5  
It is shown the 4-bromobiphenyl in soil can be decomposed quickly and almost quantitatively to organic fragments free of bromine, in a specially designed bomb in the presence of a reagent such as cuprous oxide and aqueous alkali, by using microwave energy.  相似文献   

15.
为研究建筑废物红砖和工业废物煤渣用作人工湿地脱氮基质的可行性,分别通过静态吸附实验和动态NHf—N去除效果实验进行考察。结果表明,红砖和煤渣对NH4+-N最大静态吸附量分别为0.2533mg/g和0.0533mg/g,其吸附等温曲线均符合Freundlich型吸附方程,吸附常数分别为0.0419和0.0091;红砖煤渣组合对污水中NH4+-N平均动态脱除率达到41.18%,高于红砖的37.63%和煤渣的30.92%。  相似文献   

16.
利用离子交换法制备了可磁性分离并具有高效可见光催化活性的Fe3O4/Ag3PO4复合光催化剂,对制备的样品进行了粉末X射线衍射(XRD)表征。同时,用孔雀石绿溶液模拟染料废水,考察了孔雀石绿溶液的初始浓度、催化剂投加量及溶液初始pH值对复合光催化剂催化降解孔雀石绿效果的影响,并探讨了Fe3O4/Ag3PO4磁性复合光催化剂的回收及循环利用特性。结果表明,该复合光催化剂在可见光照射下表现出较高的催化活性;当孔雀石绿溶液浓度为5mg/L、复合催化剂投加量为200mg/L、溶液初始pH=3.0、可见光照20min时,Fe3O4/Ag3PO4复合光催化剂对孔雀石绿的去除率可达96%;反应结束后,磁性复合光催化剂在外加磁场作用下,易于从反应体系中分离,循环使用3次后,其光催化效率仍可达到60%。实验表明,制备的复合光催化剂对染料废水中孔雀石绿有较高的降解效率,并具有优良的回收利用性。  相似文献   

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采用以升温充分静置分酸,洗涤水处理循环使用和碱洗废水加碱套用为核心的对硝基乙苯清洁生产工艺,可以使对硝基乙苯的收率提高5%,成本降低1500元/t,同时很好地解决了对硝基乙苯生产过程中的水污染问题。  相似文献   

19.
Tris(4-chlorophenyl)methanol (TCP) and tris(4-chlorophenyl)methane (TCPMe) were determined in aquatic organisms and sediment by a method based on Soxhlet extraction, gel permeation chromatography, fractionation over silica and gas chromatography/mass spectrometry (GC/MS) analysis. TCPMe was identified as the 4-substituted isomer after synthesis of this compound. TCP could be determined by GC/MS with negative chemical ionistation (GC/NCI-MS) with a detection limit of 0.02 g kg(-1) and a recovery of 90%. TCP concentrations in marine mammals from the North Sea and Dutch Wadden Sea ranged from 0.2 to 2 mg kg(-1), and those in marine and freshwater fish samples from 0.005 to 0.4 mg kg(-1) on a lipid wt basis. TCP concentrations in two Rhine delta sediment samples were 1.2 and 3.0 microg kg(-1) dry wt, respectively. TCPMe concentrations, determined by GC/MS with electron impact (GC/EI-MS), were 10-50% of the TCP concentration in all samples analysed.  相似文献   

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采用弹性填料微孔曝气生物预处理方法净化受污染的某饮用水源,探讨了水源水环境中NH4+-N变化对生物预处理除NH4+-N作用效果的影响。结果表明,水源水环境中的NH4+-N对生物预处理工艺除NH4+-N有一定的影响作用。  相似文献   

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