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1.
近年来,随着"退二进三"、"退城进园"和"产业转移"等政策的实施,中国几乎所有的大中城市正面临着重污染工业企业关闭和搬迁问题,城市出现大量工业遗留和遗弃场地。这些受污染的工业场地多存在较为严重的土壤、地表水和地下水污染;另外,工业污染场地的延迟再开发,会产生生活环境变差、就业机会减少、甚至社会不稳定因素增加等社会影响。所以,城市工业污染场地严重威胁着城市人居环境安全和公众健康,阻碍着城市建设和经济发展。面对工业污染场地目前存在的问题,国家及部分地方政府已针对污染场地的管理、修复及其再开发颁布了诸多文件和技术规范标准。然而,由于工业场地类型的多样性和环境管理学科的交叉性,中国城市工业污染场地的环境管理工作仍处于起步阶段,亟需完善。美国、英国和加拿大经过20~30年的发展已经在工业污染场地管理方面积累了丰富的经验,他们不仅在环境管理中体现了人体健康风险评估的理念,而且还立足本国实际出台了相关的法律法规,明确了污染场地的责任主体,实现了"污染者付费"的原则,同时还建立了各自的污染场地治理优先名录,实现了污染场地管理的信息化和网络化。本文鉴于对这些经验的比较分析,结合我国实际,就城市工业污染场地的环境管理提出了现阶段亟须解决的两大问题。首先,制定工业污染场地管理的专门法律,明确污染场地的责任主体。我国现有的与污染场地有关的国家法律法规,都比较笼统地提出了污染场地的利益相关方,缺乏具有可操作性的细则和威慑力的责任追究条款。对于我国这样地域辽阔、自然地理条件差异大、经济水平不均衡的国家来说,通过地方法律法规的建立明确污染场地的责任主体是一个重要的尝试。其次,构建污染场地健康风险评估系统。我国城市工业污染场地涉及诸多工业行业、污染类型繁多复杂。因此,在全国范围内对城市工业污染场地进行排查、建立优先污染场地名录是构建污染场地风险评估系统的重要内容。此外,我国现有的土壤质量标准和场地评估规范仍存在诸多缺陷,无法满足当前国家城市工业污染场地的管理需要。所以,完善场地评估的技术规范和相关标准将为污染场地风险评估系统的构建提供基础性保障。本文的论述和观点可为我国工业企业关停或搬迁遗留地的决策管理和污染场地管理体系的建立提供有意义的参考和借鉴。  相似文献   

2.
Organic contaminated soils have become a widespread environmental problem, which may lead to a great threat to the quality of agricultural production and to human health. Physical, chemical, and biological technologies have been employed for the mitigation and remediation of organic contaminated soils. This paper reviews the progress of mitigation and remediation technologies for organic contaminated soils and suggests two different strategies for the mitigation of ’slightly-contaminated’ agricultural soils and the remediation of ‘heavily-contaminated’ soils/sites, respectively. On this basis, directions for future research in this field are suggested.  相似文献   

3.
Stabilization is one of the best demonstrated available technologies for treating toxic pollutants in soils and has been used worldwide but is rarely used for treatment of contaminated sites in China despite many bench-scale studies. Here, a field-scale application of stabilization treatment in Shanghai, China was summarized to demonstrate the whole engineering process and the key technical issues regarding stabilization of contaminated soil. A site contaminated with arsenic (As) and polycyclic aromatic hydrocarbons (PAHs), formerly used as a lighting plant in Shanghai, was chosen as the demonstration site. Stabilizing measures were taken to treat the contaminated soil to reuse the site for residential purposes. The whole engineering remediation process consisted of phase I environmental site assessment (ESA) and phase II ESA, quantitative human health risk assessment, remediation alternatives evaluation, bench-scale testing, remedial design, engineering implementation, and post-remediation assessment. A third party conducted evaluation monitoring indicated desirable results were achieved via the stabilization treatment. In addition, some technical obstacles related to soil stabilization treatment were discussed, including soil quality evaluation, stabilization effectiveness validation, and soil reuse assessment.  相似文献   

4.
纳米零价铁的生态毒性效应研究进展   总被引:1,自引:0,他引:1  
纳米零价铁(n ZVI)由于其比表面积大、表面反应活性高以及强还原性,可以作为一种高效的环境修复材料,广泛运用于污染地下水及土壤修复。大量的n ZVI颗粒直接注射到污染位点会增加生态系统的暴露可能性,并且由于n ZVI粒径特别小,能穿过细胞膜和生物体的各类天然屏障,对环境及生态系统存在潜在风险,因此科学家们开始更多地关注n ZVI的生物安全性研究。鉴于n ZVI在环境修复应用中的巨大潜力和可能的毒性效应,对n ZVI环境风险的研究也显得尤为重要。综述了近几年国内外关于n ZVI生态毒性的研究成果,n ZVI对病毒、细菌、微生物群落、以及动植物等都能导致一定的负面效应,尽管其毒性机制尚不明确,但普遍认为n ZVI暴露后铁离子的释放和氧化损伤确实可以引起生物效应,部分研究还分析了环境因素和表面改性对其毒性的影响。文章对其未来的发展方向进行了展望,以期为今后纳米零价铁的研究提供参考。  相似文献   

5.
刘蕊  张辉  勾昕  罗绪强  杨鸿雁 《生态环境》2014,(7):1239-1244
经济的快速发展导致中国环境质量日趋恶化.随着健康意识的增强,人们越来越重视污染物暴露人群的健康风险评估.与其他污染物相比,重金属污染区域广,重金属暴露人群多且集中.为了研究重金属暴露条件下人群的健康风险,USEPA 模型、统计模型、地理信息系统、可给性研究的方法已被中国不同学者应用.暴露评估模型作为污染物暴露人群健康风险评估的主要环节,国外的研究已经比较成熟,但相关研究在中国还处于空白阶段.对中国近年来在城市表层土壤(灰尘)、矿区土壤、膳食、地下水和饮用水、大气颗粒物进行重金属风险评估中应用的健康风险评估方法,进行了归纳和评述,并对欧美常用暴露评估模型:环境暴露评估模型、膳食暴露评估模型进行了介绍.中国健康风险评估工作起步晚,在评估的各环节均存在很大缺陷.随着新技术的发展以及人群对环境健康风险认识的深化,健康风险评估将成为中国热门研究领域之一.污染的环境行为、剂量一效应关系、模型、风险信息等方面,将是未来中国健康风险评估研究的重点.  相似文献   

6.
Due to rapid urbanization and the implementation of ecological civilization construction in China, many industrial factories have been closed or relocated. Therefore, numbers of contaminated sites were generated with contaminated soils which may pose a risk to receptors living nearby. This study presented a spatial health risk assessment and hierarchical risk management policy making for mercury (Hg) in soils from a typical contaminated site in the Hunan Province, central China. Compared with the second class value (0.3 mg/kg) of the Chinese Environmental Quality Standard for Soils, the mean concentrations of Hg in the three soil depths exceeded the second class value. The non-carcinogenic risk of Hg probably posed adverse health effects in 41, 30 and 36 % of the surface soil, the moderate soil and subsoil, respectively, under a sensitive land scenario. The non-carcinogenic risk temporarily posed no adverse health effects in most areas under an insensitive land scenario except for the area around sampling site S29. Spatially, the central, southwest and northeast parts of the contaminated land under a sensitive land scenario should be regarded as the priority regions. For non-carcinogenic effects, the exposure pathways that resulted in the higher levels of exposure risk were ingestion and inhalation of vapors, followed by dermal contact and inhalation of particles. A risk-based integrated risk management policy including the hierarchical risk control values for different soil depths and the calculated remediation earthwork was proposed with consideration of the cost-benefit effect for the related decision-makers.  相似文献   

7.
污染土壤的修复技术研究进展   总被引:56,自引:6,他引:56  
分析了当前我国严峻的土壤环境状况,并从重金属和有机污染物两个方面,全面介绍了当前污染土壤的各种修复技术,包括物理化学修复方法、植物修复方法和微生物修复方法等;对各种方法的修复原理、已取得的研究进展、存在的优缺点及其将来的发展趋势进行了较全面的综述和展望。文章认为,污染土壤修复将是一项非常具有挑战性同时又是一项非常有前途的修复技术,将会对人类健康和经济可持续发展发挥重要作用。  相似文献   

8.
Groundwater is the main source of drinking water and water for agricultural and industrial usage. Therefore, groundwater contamination is prevented and contaminated groundwater is remediated to protect public health and the environment. Methods to remediate groundwater contamination have been recently developed. The use of redox processes in water remediation technologies has not been properly reviewed. Numerous water remediation technologies, such as ultrasonication, bioremediation, electrokinetics and nanotechnology, are closely related to redox processes. Redox processes control the chemical speciation, bioavailability, toxicity, mobility and adsorption of water pollutants in environment. Here, we review (1) general introduction of redox processes, (2) applicability of redox processes in water remediation, and (3) catalytic enhancement of redox potentials to explore its wide applicability in environmental remediation.  相似文献   

9.
农田重金属污染原位钝化修复研究进展   总被引:52,自引:0,他引:52  
污染土壤重金属原位钝化修复是通过向土壤中施加一些活性钝化修复材料,通过溶解沉淀、离子交换吸附、氧化还原、有机络合等反应来改变重金属在土壤中的赋存状态,降低土壤中重金属的有效浓度、迁移性和生物有效性。这种方法成本较低、操作简单、见效快且适合大面积推广,在重金属污染土壤修复中有着不可替代的作用。尤其对主要由污水灌溉、大气沉降等造成的农田土壤面源污染,一些具有吸附固定土壤中重金属离子特性的天然物质和工业副产品都可运用在实地的钝化修复中,且不同类型的钝化修复剂对重金属污染土壤的钝化修复效果各不相同。采用实验室评价和实地应用评价,一方面可以评估钝化修复材料对污染土壤中重金属离子的固定效率;另一方面可以评估钝化修复材料对土壤理化性状、养分状况和生物活性的影响。对重金属污染土壤原位钝化修复中不同来源的钝化剂进行了分类,目前广泛使用的钝化修复剂主要包括硅钙物质、含磷材料、有机物料、黏土矿物、金属及金属氧化物、生物碳及新型材料等,概述了它们各自对重金属污染土壤的钝化修复效果。从研究方法、评价指标、环境影响因子、钝化机制以及环境风险评价等方面分析了该领域的研究现状以及存在的主要问题,今后应重点关注钝化修复剂对土壤-作物系统的潜在环境风险以及钝化材料修复效果的田间长期稳定性评价。  相似文献   

10.
邻苯二甲酸酯降解细菌的多样性、降解机理及环境应用   总被引:1,自引:0,他引:1  
邻苯二甲酸酯(phthalic acid esters,PAEs)是一类对人体内分泌系统有干扰作用的持续性有机污染物(persistent organic pol utants,POPs)。PAEs在环境介质如水体、底泥和土壤中长期赋存会对生物体产生毒害效应,其分布广、浓度高和难降解等特点是限制有效环境治理的主要因素。作为环境的重要组成部分,微生物对污染物有很强的适应能力和高效的降解能力,这为PAEs的生物修复提供了可能。与物理化学修复法相比,微生物修复技术具有可控性强、修复面广和灵活性高等优势。本文综述了已报道的大部分PAEs降解细菌的种类及其代谢机制,并分析了其在PAEs污染水体和土壤修复中的应用现状与前景,以期为PAEs环境行为与生物修复研究提供参考。  相似文献   

11.
随着水环境外污染源得到有效控制,底质污染逐渐成为人们关注的焦点.底质中的污染物尤其是难降解有机物可通过生物富集和生物放大等过程,进一步影响陆生生物和人类的健康.因此,对底质中难降解有机物的修复是目前所迫切需要解决的环境问题之一.基于异位修复成本较高易造成二次污染等缺点,文章针对难降解有机物污染底质,探讨了原位修复技术的研究进展,自然修复成本较低,对生态环境不产生干扰,但不适用于高浓度污染底质;植物修复操作简单,能有效防止污染底质再悬浮,但对高浓度难降解有机物耐受性较低;微生物修复适用范围广,修复效果较为显著,但菌体易流失,对环境的适应性较差.于是,固定化修复技术应运而生,固定化技术能解决传统的微生物修复存在的很多问题,但固定化载体的重复可利用性和再生性问题仍有待解决.文章最后对今后难降解有机物污染底质的研究方向进行了展望,由于污染底质多为复合污染,各取所长的联合修复技术将成为未来的研究热点.  相似文献   

12.
In this research, a risk assessment was undertaken in order to develop the remediation and management strategy of a contaminated gunnery site, where a nearby flood controlling reservoir is under construction. Six chemicals, including explosives and heavy metals, posing potential risk to environmental and human health, were targeted in this study. A site-specific conceptual site model was constructed, based on effective, reasonable exposure pathways, to avoid any overestimation of the risk. Also, conservative default values were adapted to prevent underestimation of the risk when site-specific values were not available. The risks posed by the six contaminants were calculated using the API’s Decision Support System for Exposure and Risk Assessment, with several assumptions. In the crater-formed-area (Ac), the non-carcinogenic risks (i.e., HI values) of tri-nitro-toluene (TNT) and Cd were slightly larger than 1, but for RDX (Royal Demolition Explosives) was over 50. The total non-carcinogenic risk of the whole gunnery range was calculated to be 62.5, which was a significantly high value. The carcinogenicity of Cd was estimated to be about 10−3, while that for Pb was about 5 × 10−4, which greatly exceeded the generally acceptable carcinogenic risk level of 10−4–10−6. It was concluded from the risk assessment that there is an immediate need for remediation of both carcinogens and non-carcinogens before construction of the reservoir. However, for a more accurate risk assessment, further specific estimations of the changes in environmental conditions due to the construction of the reservoir will be required; and more over, the effects of the pollutants to the ecosystem will also need to be evaluated.  相似文献   

13.
北京市某废弃化工厂的人类健康风险评价   总被引:17,自引:0,他引:17  
由于北京城市化速度的加快,五环路内的工厂将陆续搬迁,搬迁后的土地,使用功能将发生根本性变化,由于修复成本较高,是否对受污染土地进行修复,需要借助健康风险评价,以便确保人们的健康安全.运用美国的健康风险评价框架,对北京市某废弃化工厂场地进行了健康风险分析,计算了将该废弃场地用作居住用地对人类的健康风险指数及确定是否需要进行修复.在场地内,分2次进行了3层土壤采样,共采集到80个样品.选取Cr、Zn、Ni、Pb、Hg、Cu、As、Cd、DDT、六六六(HCH)和邻苯二甲酸二辛酯(DP)11种超标污染物作为目标污染物,对其进行健康风险评价.按照美国EPA的方法,选取了95%置信上限含量进行风险指数的计算.评价结果显示,该场地成人的非致癌风险指数为15.85,儿童的非致癌风险指数为18.17,均超过了非致癌风险指数可接受值1.0,表明该化工厂场地对成人和儿童均有非致癌风险;对成人,邻苯二甲酸二辛酯的致癌风险指数为不可接受值(>1×10-4),对儿童,邻苯二甲酸二辛脂和DDT的致癌风险为不可接受值(>1×10-4),其它污染物的致癌风险均在可接受范围之内.由于案例中的场地将被用作居住用地,建议对该场地进行部分修复.  相似文献   

14.
In South West England, more than two hundred years of intensive exploitation of metalliferous ore deposits, combined with the natural processes of pedogenesis from mineral-rich parent rocks, has resulted in the creation of a aignificant area of arsenic-contaminated wastes and soils. The scale of arsenic dispersion by natural and anthropogenic processes is such that 722 km2 of land contains concentrations of arsenic in excess of 110 g g–1, more than twice the maximum that might be expected in a normal soil.The general rationale for the clean-up of derelict and contaminated mining sites often includes aesthetic factors and the desirability of preventing the dispersion of contaminants beyond the site boundaries. Only in extreme cases is public health directly invoked as justification for remediation. In South West England, if arsenic constitutes a genuine threat to the public, an increased rate of site remediation would be justified. The primary purpose of this review is to establish whether or not widespread arsenic contamination (principally of soils) has any measurable effects on public health in South West England, and how this might affect current contaminated site remediation policy. The review is based on data from previous research in the region, and other relevant international studies of mining and smelting communities, and other populations exposed to elevated arsenic concentrations. The literature reviewed also includes the determination of the extent and sources of contamination, and pathways between source and man.While the contamination of potable waters in some countries has led to measurable health effects, this scenario has not yet been identified in South West England, and there is little reason to believe that significantly contaminated potable water supplies would escape detection for extended periods of time under the current monitoring regime.In relative terms (based on both globaland local data), one of the most significant links between contaminated soils and humans appears to be contaminated food stuffs. In absolute terms, such exposure is low due to the natural constraints on arsenic uptake by herbage, cereal crops and vegetables, and the food chain does not appear to have been significantly compromised in South West England. Chronic health effects are unlikely as excessive arsenic concentrations in locally grown food crops remain rare.With the problems of confounding medical and social factors, it is not surprising that studies in South West England have failed to identify chronic exposure to arsenic at very low concentrations as a significant health risk. Those studies that indicate otherwise do not stand up to close scrutiny. It appears that the number of additional deaths arising from the widespread arsenic contamination in South West England is small. The relative benefits of a costly statistical study to actually determine the number of additional deaths might be considered minimal, but one major area could benefit from further studies: the sensitivity of certain population sub-groups to environmental arsenic exposure. Of particular interest are children, for whom significant exposure to arsenic via soil ingestion may be occurring.Based on available information, there appears to be no justification for a large programme of site remediation. Resources should, however, be expended on enlightening the general public, and private and governmental organisations as regards the gap between the perceived and actual significance of arsenic contamination in South West England.To whom correspondence should be addressed.  相似文献   

15.
中国天然水体中五氯酚的浓度水平、管理及来源分析   总被引:1,自引:0,他引:1  
五氯酚(PCP)属内分泌污染物,也是可对生物产生复合毒性的有机污染物。五氯酚及其钠盐曾被用作杀螺剂在我国血吸虫病流行疫区大范围长时间使用。为了解PCP在中国水环境中的污染现状,在阐述中国PCP的生产使用状况基础上,重点论述中国水环境介质中PCP的污染分布及影响因素。中国多地河流水环境中均存在PCP,其中沿长江流域的长江、洞庭湖、鄱阳湖PCP残留量较高,虽均在限值范围内,但PCP污染范围有从主要江河、湖泊等向沿海海域蔓延的趋势。PCP使用历史、用药区域类型、区域PCP消耗量等均会影响PCP的残留量,血吸虫病疫区PCP残留量明显高于对照区,在PCP及其钠盐显著减少使用后(2003年以后),施药历史仍然影响着水体介质中PCP的残留情况,PCP虽已停用,但其对环境所造成的不良影响还在持续。与国外研究相比,我国水环境介质中的PCP污染偏高且有上升趋势,这可能与部分区域近年来重现血吸虫病后施药控制有关。未来一段时期内有关PCP及其环境副产物在环境介质中的迁移转化规律、人群暴露评估、污染介质修复技术以及其替代品的研制都将是研究重点领域。  相似文献   

16.
2种毒性评估方法对PAHs污染场地人体健康风险的比较研究   总被引:2,自引:0,他引:2  
毒性评估是人体健康风险评价的重要部分,目前主要存在2种方法,一种基于PAHs相对于苯并[a]芘(BaP)的毒性当量因子,采用Ba P致癌斜率因子参数(方法 1),另一种直接采用各PAHs致癌斜率因子和非致癌参考剂量等参数(方法 2)。然而2种毒性评估方法得到的风险及修复量是否存在差异以及引起差异的原因等问题鲜有讨论。针对苏南某焦化厂PAHs污染土壤,采用分层土壤健康风险评价模型,对比了2种毒性评估方法确定的PAHs风险、修复目标污染物及土方量的差异,并对引起差异的关键因素进行探讨。结果表明:对于0.0~1.0 m表层土壤,方法 1和方法 2确定的致癌风险最大值分别1.48E-05和1.32E-05,均超过可接受致癌风险,修复土方量分别为27 846 m~3和28 667 m3,修复目标污染物均为Ba P和二苊烃(Acy)。对于1.0~3.0 m深层土壤,方法 1确定的致癌风险最大值为3.36E-08,低于可接受致癌风险,不需要修复;而方法 2确定的致癌风险最大值为3.73E-04,非致癌危害指数最大值为6.96E+01,分别超过可接受致癌风险和非致癌危害商,需要修复,修复目标污染物为萘(NaP),修复土方量为35 944 m~3。最终,方法 2确定的总修复土方量(64 611 m~3)为方法 1确定土方量(27 846 m~3)的2.45倍,而这种差异主要是由于方法 1低估了深层土壤中高挥发性PAH单体尤其是NaP的风险所致。因此,从保守角度建议采用方法 2进行PAHs风险评价。  相似文献   

17.
The Ministry of Environmental Protection of China issued a 3rd draft edition of risk-based Generic Assessment Criteria (the MEP-GAC) in March 2016. Since these will be the first authoritative GAC in China, their implementation is likely to have a significant impact on China’s growing contaminated land management sector. This study aims to determine the potential implementation impact of the MEP-GAC through an in-depth analysis of the management context, land use scenarios, health criteria values adopted and exposure pathways considered. The MEP-GAC have been proposed for two broad categories of land use scenarios for contaminated land risk assessment, and these two categories of land use scenarios need to be further delved, and a MEP-GAC for Chinese cultivated land scenario ought to be developed, to ensure human health protection of Chinese farmers. The MEP-GAC have adopted 10?6 as the acceptable lifetime cancer risk, given the widespread extent and severe level of land contamination in China, consideration should be given to the decision on excess lifetime cancer risk of 10?5. During risk assessment process in practice, it is better to review the 20% TDI against local circumstances to determine their suitability before adopting it. The MEP-GAC are based on a SOM value of 1%, for regions with particularly high SOM, it might be necessary to develop regional GAC, due to SOM’s significant impact on the GAC developed. An authoritative risk assessment model developed based on HJ25.3-2014 would help facilitate the DQRA process in practice. The MEP-GAC could better reflect the likely exposures of China’s citizens due to vapour inhalation by using characteristics of Chinese exposure scenarios, including China-generic building stock, as inputs into the Johnson and Ettinger model as opposed to adoption of the US EPA parameters. The MEP-GAC once implemented will set the trajectory for the development of the investigation, assessment and remediation of land contamination for years.  相似文献   

18.
农田土壤重金属污染状况及修复技术研究   总被引:33,自引:0,他引:33  
重金属污染因具有毒性、易通过食物链在植物,动物和人体内累积,对生态环境和人体健康构成严重威胁。随着工业快速发展、农药及化肥的广泛使用,农田土壤重金属污染越来越严重,研究农田土壤重金属污染现状及修复技术对农产品安全具有重要意义。综合国内外农田土壤重金属污染状况,农田土壤重金属污染主要来源于固体废弃物堆放及处置、工业废物大气沉降、污水农灌和农用物质的不合理施用。该文综述了国内外有关农田重金属污染土壤修复技术(物理修复、化学修复、生物修复、农业生态和联合修复)的研究进展,并针对各种修复方法,阐述了其原理、修复条件、应用实例及其优缺点,重点论述了植物修复的机理和应用,提出了草本与木本联合修复可有效提高农田土壤重金属复合污染的修复效率,为农田土壤土壤重金属复合污染修复提出了新的途径。最后在对已有研究分析的基础上,提出了联合修复技术(如生物联合技术、物理化学联合技术和物理化学-生物联合技术)可以在一定程度上克服使用单一修复手段存在的缺点,可提高复合污染的修复效率、降低修复成本,未来应深入探索联合修复技术间的相互作用机理,以期为农田土壤重金属综合治理与污染修复提供科学依据。  相似文献   

19.
频发的污染事故严重影响环境质量,危害人群健康,事故的源解析和修复成为了关键问题。而传统的靶向分析方法无法胜任实际工作需求。因此,本研究建立了1)有毒有害物质清单;2)一种针对有毒有害物质的快速高效鉴别方法。将上述方法应用于某场地污染事件,成功筛查鉴定出30种环境高关注度物质,通过数据库比对进一步鉴定了6种危废物质,通过购买标准样品成功验证了4种物质。同时,还通过文献查阅与标样比对确认了另外2种有毒物质。因此,本研究建立的有毒有害物质快速筛查方法为实际环境中的污染物快速鉴别提供了一种可靠的、可行的方法。  相似文献   

20.
通过对欧洲国家及澳大利亚、新西兰所使用的风险评价与风险管理方法的全面回顾和综合分析,探讨了各种不同方法的异同及利弊,辨识了环境和人类健康风险的有效、通用和综合方法中所遵循的决策清单.根据先进国家的经验,提出了构建中国环境风险管理的标准、结构及流程,以期为我国环境风险管理提供决策支持.  相似文献   

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