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1.
土壤中多环芳烃的微生物降解: 降解途径及其影响影子 总被引：4，自引：0，他引：4
Adverse effects on the environment and high persistence in the microbial degradation and environmental fate of polycyclic aromatic hydrocarbons (PAHs) are motivating interest. Many soil microorganisms can degrade PAHs and use various metabolic pathways to do so. However, both the physio-chemical characteristics of compounds as well as the physical, chemical, and biological properties of soils can drastically influence the degradation capacity of naturally occurring microorganisms for field bioremediation. Modern biological techniques have been widely used to promote the efficiency of microbial PAH-degradation and make the biodegradation metabolic pathways more clear. In this review microbial degradation of PAHs in soil is discussed, with emphasis placed on the main degradation pathways and the environmental factors affecting biodegradation. 相似文献
2.
Ritu PANWAR Jyoti MATHUR 《土壤圈》2023,33(1):93-104
Polycyclic aromatic hydrocarbon(PAH) pollution is a global concern because of their toxicity to environment and ecosystem, which induces adverse effects on plants, animals, and humans. Hydrocarbons are mainly released from natural and anthropogenic activities, such as incomplete fuel combustion, leakages in oil pipelines, and the extensive use of pesticides; PAH contaminants include petroleum hydrocarbons(PHCs), halogenated hydrocarbons, chlorophenols, and pesticides. Bioremediation using microo... 相似文献
3.
筛选有机氯农药(六六六和滴滴涕)和多环芳烃作为典型土壤有机污染物,以江西省为例,开展了污染评价、源识别以及健康风险评价研究。结果表明:(1)所有样品中总六六六均未超过我国土壤环境质量二级标准,有8个样品中总滴滴涕超过该标准,另外,7.9%的样品中总多环芳烃超过荷兰土壤环境质量标准中最高允许浓度阈值;(2)接近29%的样品中六六六来自于当前林丹的使用,滴滴涕主要来源于近期输入,而对于多环芳烃而言,其中66%的样品中多环芳烃来源于石油源,34%的样品来源于燃料燃烧;(3)有机氯农药和多环芳烃对人体健康的风险都在可接受的范围内。 相似文献
4.
Used lubricating oils are majorsources of polycyclic aromatic hydrocarbons (PAHs) inmarine environments. This study presents an improvedmethod for characterization PAHs in used lubricatingoils. Recoveries of sixteen certified PAHs spikedinto used lubricating oil indicated this method wasmore precise and efficient than those reportedpreviously. Aromatic and aliphatic compounds in usedlubricating oil were extracted by dimethylsulfoxide,then separated by a silica gel column using hexane anddichloromethane as solvents. Finally, gaschromatography-mass spectrometry was used inqualitative and quantitative analysis of various PAHsin oil samples. Sixteen certified PAHs andeighty-three other PAHs were identified and quantified usingPAH standards and previously reported retentionindices as references. The improved method was usedto determine PAH profiles in lubricating oil samplescollected from a gasoline-driven automobile aftervarious driving distances. One hundred and eightyaromatic compounds, including ninety-nine PAHs, wereidentified by the gas chromatographic method. Theseresults suggested that the new method was superior tomethods described in previous studies. Theconcentrations of PAHs, including the comparativelytoxic 5-ring PAHs, increased rapidly even after theautomobile had only been driven for a short distance. 2- and 3-ring PAHs, most of them are alkylated,dominated the PAH profiles of the collected oil samples. 相似文献
5.
近年来黄河兰州段的多环芳烃污染日渐严重。为研究黄河兰州段水体中多环芳烃类有机污染物对人体产生的潜在健康危害风险,根据黄河兰州段2004年11个采样点水质监测数据,应用美国环境保护局（USEPA）的健康风险评价方法对黄河兰州段多环芳烃类有机污染物通过饮水和皮肤接触途径进入人体的健康风险进行了初步评价。结果表明：黄河兰州段多环芳烃类有机污染物的非致癌风险指数值均小于1,其中萘的非致癌风险指数值在10^-3数量级,偏高于其他污染物。苯并（a）芘的致癌风险指数值在10^-4数量级以下。从位于西固八盘峡的1号采样点（S1）采集的水样中萘的非致癌风险指数值偏高。在所有采样点中,西固八盘峡的1号采样点（S1）污染较重,具有较高的健康风险。与国内其他地区相比,黄河兰州段萘的非致癌风险亦较高。常规的自来水处理工艺不能有效地去除源水中微量PAHs等有机污染物,因此地面水特别是饮用源水PAHs污染具有较大的健康风险。 相似文献
6.
Biodegradation of pyrene and catabolic genes in contaminated soils cultivated with Lolium multiflorum L 总被引：1，自引：1，他引：0
Sardar Khan Abd El-Latif Hesham Gu Qing Liu Shuang Jizheng He 《Journal of Soils and Sediments》2009,9(5):482-491
Background, aim, and scope
In the soil environment, polycyclic aromatic hydrocarbons (PAHs) and heavy metals (HMs) are of great environmental and human health concerns due to their widespread occurrence, persistence, and carcinogenic properties. Bioremediation of contaminated soil is a cost-effective, environmentally friendly, and publicly acceptable approach to address the removal of environmental contaminants. However, bioremediation of contaminants depends on plant–microbe interactions in the rhizosphere. The microorganisms that can mineralize various PAHs have PAH dioxygenase genes like nahAc, phnAc, and pdo1. To understand the fate of pyrene in rhizospheric and non-rhizospheric soils in the presence or absence of Pb, pyrene biodegradation, bacterial community structure, and dioxygenase genes were investigated in a pot experiment. 相似文献7.
Abstract. Different types of contaminants such as polycyclic aromatic hydrocarbons (PAHs) and metals coexist in different chemical forms in soil. Although bioremediation of organics has been widely studied, little attention has been paid to changes in metal behaviour during the bioremediation process. In this study, the diffusion gradient in thin-film (DGT) technique was used to assess changes in potentially bioavailable Cd and Cr fluxes in soil during the bioremediation of phenanthrene. Fluxes of Cd were low (< 0.2pgcm−2 s−1 ) and increased to 0.4–0.9 pg cm−2 s−1 , while Cr(III) fluxes showed an approximately tenfold increase. Results showed that there was increased mobilization of metals associated with the fungal reduction of phenanthrene concentrations by Penicillium frequentans. 相似文献
8.
Simulation of polycyclic aromatic hydrocarbon remobilization in typical active regions of river system under hydrodynamic conditions 总被引：1，自引：0，他引：1
Purpose
In an aquatic environment, hydrodynamic condition is a ubiquitous natural process, and the contaminated sediments will act as a potential pollution source once they are remobilized into the overlying water. In this study, remobilization behavior of polycyclic aromatic hydrocarbons (PAHs) under simulated hydrodynamic conditions was studied. Additionally, an adjusted prediction model with addictive consideration of surface properties was developed to exhibit the distribution of PAHs in hydrodynamic system. 相似文献9.
10.
多环芳烃污染土壤生物联合强化修复研究进展 总被引：9，自引：1，他引：9
多环芳烃(polycyclic aromatic hydrocarbons,PAHs)是广泛存在于环境中的一类有毒有机污染物。在PAHs污染土壤修复领域中,运用一些生物化学的方式来强化生物联合修复技术可以有效缩短生物修复的时间,大大提高修复效率,最具发展前景和应用价值。本文主要以植物-微生物、植物-微生物-土壤动物两种生物联合修复方式为对象,结合各自的特点、机理和实例,推断了其修复机制的内在原因,总结了影响土壤中PAHs降解效率的主要因素(包括:PAHs的浓度水平、根系分泌物的种类、外源添加降解菌和土壤动物的数量和种类、菌属或土壤动物之间的种间竞争和部分环境因素等);同时通过综述近年来国内外强化生物联合修复PAHs污染土壤的技术原理、应用成果和存在的一些问题,指出了不同情况下制约PAHs强化降解进程的潜在限制因子(包括:表面活性剂和固定化微生物的添加量、不同表面活性剂的适度混合、载体材料的性质、固定化方式的选取、土壤养分和水分含量等);并强调在进行强化修复的过程中,要注重现场应用和安全性评价,为多环芳烃污染土壤的生物联合强化修复研究提供了理论依据和技术参考。 相似文献
11.
随着人类活动对地球环境的影响日益显著,土壤污染问题已成为社会关注的焦点。我国土壤修复起步较晚,且修复技术仅局限于物理、化学等常规手段。随着国家对污染防治攻坚战的深入推进,修复领域亟需高效、低耗、环保的新技术出现,而生物修复可以一定程度弥补现有修复技术的缺陷。因此,通过与传统物理化学修复比较,探究了生物技术（如动物、植物、微生物技术）的优势、使用特点及适用范围,对国内外生物土壤修复技术进行了计量分析。文献调研结果显示:①土壤生物修复主要关注多环芳烃、重金属等污染物,并且微生物技术是研究热点,前期主要探究降解菌的分离鉴定,现阶段则集中于相关机理分析;②动物修复技术的主体模式生物单一,主要利用蚯蚓的生物性和非生物性特性进行修复,在土壤修复中应用较少;③植物修复技术因其多样的修复机理,广泛应用于重金属污染场地,同时可与微生物协同处理污染物;④微生物修复技术主体多样,修复污染物种类多,并且可与其他修复技术联合应用,在生物修复技术中研究最为广泛;⑤对国内土壤修复的发展方向进行展望,以期推动我国修复领域技术的快速发展。 相似文献
12.
Enhanced bioremediation of PAH-contaminated soil by immobilized bacteria with plant residue and biochar as carriers 总被引：2，自引：0，他引：2
Purpose
Polycyclic aromatic hydrocarbons (PAHs) are largely accumulated in soils in China. The immobilized-microorganism technique (IMT) is a potential approach for abating soil contamination with PAHs. However, few studies about the application of IMT to contaminated soil remediation were reported. Due to recalcitrance to decomposition, biochar application to soil may enhance soil carbon sequestration, but few studies on the application of biochars to remediation of contaminated soil were reported. In this study, we illustrated enhanced bioremediation of soil having a long history of PAH contamination by IMT using plant residues and biochars as carriers.Materials and methods
Two PAH-degrading bacteria, Pseudomonas putida and an unidentified indigenous bacterium, were selected for IMT. The extractability and biodegradation of 15 PAHs in solution and an actual PAH-contaminated soil amended with immobilized-bacteria materials were investigated under different incubation periods. The effects of carriers and the molecular weight of PAHs on bioremediation efficiency were determined to illustrate their different bio-dissipation mechanisms of PAHs in soil.Results and discussion
The IMT can considerably enhance the removal of PAHs. Carriers impose different effects on PAH bio-dissipation by amended soil with immobilized-bacteria, which can directly degrade the carrier-associated PAHs. The removal of PAHs from soil depended on PAH molecular weight and carrier types. Enhanced bio-dissipation by IMT was much stronger for 4- and 5-ring PAHs than for 3- and 6-ring ones in soil. Only P400 biochar-immobilized bacteria enhanced bio-dissipation of all PAHs in contaminated soil after a 90-day incubation.Conclusions
Biochar can promote bioremediation of contaminated soil as microbial carriers of IMT. It is vital to select an appropriate biochar as an immobilized carrier to stimulate biodegradation. It is feasible to use adsorption carriers with high sorptive capabilities to concentrate PAHs as well as microorganisms and thereby enhance dissipation of PAHs and mitigate soil pollution. 相似文献13.
蚯蚓和发酵牛粪促进南瓜苗修复PAHs污染农田土壤 总被引：1，自引：1，他引：0
为了寻求高效修复土壤中持久性有机污染物多环芳烃(PAHs,polycyclic aromatic hydrocarbon),在温室盆栽试验条件下,研究接种蚯蚓和施用发酵牛粪对南瓜苗修复3环以上PAHs污染土壤的影响。试验设置施用牛粪(D)、单接蚯蚓(E)、接种蚯蚓和施用牛粪(ED)、不接种蚯蚓和不施用牛粪的对照(CK)共4个处理,播种10周后收获。研究结果表明,接种蚯蚓和施用牛粪的共同作用下能有效提高南瓜苗生物量,有利于南瓜苗在PAHs污染的土壤生长,特别是地上部分的生长;接种蚯蚓或/和施用牛粪有效地提高了南瓜苗从土壤中吸收3～5环PAHs化合物的效率,且南瓜苗地上部吸收的PAHs量最低是地下部的6倍。因此,结合蚯蚓和发酵牛粪的辅助作用,南瓜苗地上部生物量较大,能从土壤中吸收多种PAHs化合物,与仅依赖于土壤自身的作用相比,三者的共同作用使得土壤中3环以上PAHs化合物的去除率提高23%以上,可组合应用于PAHs污染土壤的强化修复。该研究为土壤多环芳烃污染修复提供参考。 相似文献
14.
Earthworms can accelerate the removal of contaminants from soil. Earthworms change the physical and chemical properties of soil by mixing it with organic material and through their burrowing they improve aeration and render contaminants available for microorganisms. The presence of earthworms in contaminated soil indicate that they can survive a wide range of different organic contaminants, such as pesticides, herbicides, polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and crude oil, at least when concentrations of the contaminant are not too high. The improvement of the soil due to their activity and the microorganisms in their digestive track can contribute to the accelerated removal of contaminants from soil, but sometimes their casts adsorb the pollutant so that its dissipation is delayed. There are limits, however, on how earthworms can be used to remediate soil, which will be discussed in this review. 相似文献
15.
Availability of polycyclic aromatic hydrocarbons in aging soils 总被引：1，自引：0，他引：1
Wanting Ling Yuechun Zeng Yanzheng Gao Hongjiao Dang Xuezhu Zhu 《Journal of Soils and Sediments》2010,10(5):799-807
Purpose
The soil contamination by hydrophobic organic contaminants (HOCs), such as polycyclic aromatic hydrocarbons (PAHs), poses great threats to human health and ecological security and attracts worldwide concerns. The total HOC concentrations overestimate its available fraction to the soil biota. Increased understanding of the availabilities of PAHs in soil environment will have considerable benefits for their risk assessment and be very instructive to food safety and remediation strategies in contaminated sites. However, the availability of PAHs in aging soils and particularly the correlations of the availabilities with their forms in soils have yet to be elucidated. In this work, the availabilities of PAHs in aging soils were evaluated using a sequential mild extraction technique. 相似文献16.
Rey-Salgueiro L García-Falcón MS Soto-González B Simal-Gándara J 《Journal of agricultural and food chemistry》2004,52(12):3900-3904
Before wood ash can be safely used as a fertilizer in soils, possible negative effects such as input of organic contaminants or remobilization of contaminants already stored in the soil must be investigated. The objective of this study was to optimize and characterize extraction methods to isolate and quantitatively measure polycyclic aromatic hydrocarbons (PAHs) concentrations in wood ash that can be used as amendment of soils. It will be then possible to examine the effects of wood ash application on PAHs concentrations in the washing waters with the aim of evaluating their distribution by storage in the different compartments and what influences their stability and persistence. Simple, rapid and inexpensive methods have been set up for the determination of seven polycyclic aromatic hydrocarbons (PAHs) in wood ashes and ash aqueous extracts without interferences from other chemical contaminants using organic solvent extraction and/or SPE techniques and analyzed by an optimized RP-HPLC-FLD method. The feasibility of extraction for the determination of PAHs in wood ashes has been evaluated because PAHs are strongly sorbed to such a matrix, which explains why the PAHs content in ash was seldom studied. The method resulted to be of recoveries ranging from 81 to 97% for the different PAHs, with repeatabilities (RSDs%) better than 6%. Detection levels were from 0.2 to 2.2 microg/kg, while quantification limits were from 0.7 to 5.6 microg/kg, low enough to evaluate the presence of PAHs in wood ashes. 相似文献
17.
微生物降解石油源多环芳香烃的研究进展 总被引：1，自引：0，他引：1
石油源多环芳香烃是存在于石油中的一类致畸、致癌污染物,具有以低环(2~3环)为主且取代基比例明显高于其他来源PAHs的组分特征。石油泄露引发的PAHs污染,其降解主要依赖于微生物的活动。本文对能够降解PAHs的微生物种类、降解机理、代谢途径及编码基因进行了概述。从PAHs作为碳源的角度将微生物降解机理划分为能以PAHs为唯一碳源进行生长的降解机理和共代谢机理。对与PAHs有关的好氧和厌氧微生物降解途径及对应的编码基因簇进行了总结。自然界中细菌、放线菌、真菌及藻类都能够降解PAHs,由加氧酶催化的苯环羟基化和还原酶介导的苯环脱芳烃化是好氧和厌氧降解途径的关键步骤,与降解有关的pca,cat,paa,nah,nah-like和bcr基因簇则分别调控好氧和厌氧降解过程。这些进展有助于系统了解石油源PAHs的降解过程、微生物作用机理和分子遗传机制,为进一步利用微生物促进环境生物修复提供理论依据。 相似文献
18.
Franz Zehetner Ulrike Rosenfellner Axel Mentler Martin H. Gerzabek 《Water, air, and soil pollution》2009,198(1-4):125-132
Automobile traffic pollutes roadside environments with a range of contaminants. In this study, we investigate the distribution patterns of different contaminant classes in topsoils across a highway-forest interface north-east of Vienna, Austria, in order to assess spatial pollutant distribution and evaluate the filtering effect of roadside forests. We collected soil samples along transects perpendicular to the highway, and analyzed the soils for road salt residues (Na), total and mobile heavy metals (Pb, Cd, Cu, Zn, Ni, Cr) as well as polycyclic aromatic hydrocarbons (PAHs). Roadside soil pollution was highly heterogeneous. All contaminants followed an exponential-like decrease with distance from the road, reaching background levels at 5 to 10 m from the road curb. Traffic-born heavy metals in the immediate roadside zone tended to be more mobile than heavy metals of predominantly geogenic origin at greater distances from the road; the presence of road salt residues could have contributed to the elevated heavy metal mobility near the road. The forest vegetation acted as filter for PAHs shown by a sharp concentration increase at the forest edge. PAHs are likely transported with airborne soot particles that are scavenged by the wax-coated coniferous needles at our study site. 相似文献
19.
Natural factors ensuring soil tolerance toward pollution with technogenic hydrocarbons, particularly, oil products and polycyclic aromatic hydrocarbons, are considered. The maps of the self-purification capacity of the soils of Russia and its particular humid and arid regions with respect to their contamination with technogenic hydrocarbons are analyzed. The principles lying in the basis of these maps are discussed. It is argued that the cartographic assessment of soil tolerance toward pollution with technogenic hydrocarbons is necessary for setting the values of maximum permissible concentrations of hydrocarbons in soils, for the choice of adequate soil rehabilitation procedures, and for the organization of soil monitoring. 相似文献
20.
? Environmental contamination by synthetic polynuclear aromatic hydrocarbons (PAHs) has become a major pollution problem. Plant tissues, lignin, soil humus constituents, some pesticides, and numerous commercial organic chemicals are also based upon aromatic building blocks. Many of these molecules are potentially toxic and carcinogenic. Some PAH compounds occur naturally at a low concentration in soils. Long exposure to naturally occurring hydrocarbons has enabled bacteria to evolve enzymes that degrade them.Landfarming and incineration are the primary technologies used for removing PAH compounds from soils and groundwater. Recent data suggest that bioremediation by PAH composting can offer significant advantages to other treatment alternatives. Landfarming is a relatively uncontrolled method of reducing PAHs in residues. Composting is quicker, more controlled, and requires less space than landfarming. Although composting is slower and less complete than incineration, it is significantly more cost-effective.This presentation deals with the feasibility of composting PAH contaminated soils and residues. Included will be methods for process evaluation and control, degradation potential of specific PAHs, and determining the application of composting to specific situations. 相似文献