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1.
海河干流、大沽排污河沉积物中有机氯农药的残留状况   总被引:7,自引:0,他引:7  
调查了海河干流和大沽排污河沉积物中持久性有机氯杀虫剂(OCPs)的残留状况.在所选取的16个断面沉积物样品中均有大量HCHs、DDTs检出,表明海河和大沽排污河的DDT和HCH污染相当严重.海河沉积物中HCHs和DDTs总质量浓度分别为3.30~75.96、1.57~221.57 ng/g.大沽排污河沉积物中HCHs和DDTs的残留量分别为2.30~124.61、11.28~237.30ng/g.与国内外部分河流表层沉积物中HCHs、DDTs的含量相比,海河和大沽排污河沉积物中有机氯农药含量较高.最后根据两条河流沉积物中的OCPs的残留量,分析了其可能的污染源.  相似文献   

2.
渤海湾潮间带表层和柱状沉积物中有机氯农药的沉积记录   总被引:2,自引:0,他引:2  
测定了渤海湾潮间带表层和柱状沉积物样品中有机氯农药(OCPs)浓度,探讨了OCPs的垂直分布特征,结合柱状沉积物测年结果,研究了该区域OCPs的污染历史。结果表明,潮间带表层沉积物样品中OCPs为78.51~172.10 ng/g(以干质量计,下同),平均值为112.92 ng/g;六六六(HCHs)、滴滴涕(DDTs)、七氯的检出率和残留量均较高,其中HCHs为8.08~56.33 ng/g,平均值为26.35 ng/g;DDTs为5.18~45.02 ng/g,平均值为28.25 ng/g;七氯为10.15~77.16 ng/g,平均值为48.33 ng/g。该区域20世纪50年代开始使用OCPs,70年代达到最高峰。成分分析的结果表明,可能存在着DDTs类物质的输入。  相似文献   

3.
重庆典型岩溶区地下河表层沉积物OCPs初步研究   总被引:3,自引:0,他引:3  
利用GC-ECD对重庆典型岩溶区地下河表层沉积物中19种有机氯农药进行分析,结果表明,研究区总有机氯农药浓度为4.73~286.03 ng/g,DDTs浓度为0.35~181.78 ng/g,HCHs浓度为nd~23.53 ng/g。与国内外其他河流表层沉积物有机氯农药相比为高,说明重庆典型岩溶区地下河已处于较高污染状态。统计DDE/DDD发现,除姜家溶洞外,其他取样点DDE/DDD均大于1,表明研究区DDT降解主要在好氧环境中进行。除靛水地下河,其他取样点表层沉积物(DDD+DDE)/DDT均大于0.5,表明这些地区近年来没有新的DDT类农药输入。  相似文献   

4.
分析了冀中典型农业区土壤-农作物体系中有机氯农药(OCPs)残留与生物富集特征,探讨了该地区所产农作物的可食部分对人体健康产生的潜在风险。结果表明:11种OCPs以滴滴涕(DDTs)和六六六(HCHs)为主要残留物。土壤中DDTs和HCHs残留量总计达36.52~73.45ng/g,在各自的异构体中p,p’-DDT和γ-HCH所占比例最高,表明OCPs污染主要为近期输入所致。玉米和小麦各器官中,OCPs均在籽粒中最高,分别残留20.66~33.33、19.14~34.57ng/g。小麦和玉米对HCHs的富集能力均强于DDTs。研究显示,该地区玉米与小麦籽粒中OCPs含量虽未超过《农产品安全质量无公害蔬菜安全要求》(GB 18406.1—2001)和《食品安全国家标准食品中农药最大残留限量》(GB 2763—2012),但OCPs致癌总风险相对较高,玉米和小麦中均超过了1×10-6,小麦中OCPs的非致癌总风险和致癌总风险均大于玉米,因此该地区应该优先关注OCPs对小麦所造成的粮食安全问题。  相似文献   

5.
吕杨  王立宁  黄俊  王泰 《环境污染与防治》2007,29(9):652-655,660
从海河、渤海湾水域内采集了沉积物和鱼体(鲫鱼)样品.采用气相色谱/质谱(GC/MS)方法测定了样品中的多溴联苯醚(PBDEs).结果表明,沉积物(以干重计)和鱼体(以干重计)中PBDEs的检出水平分别为0.35~5.53、6.81~35.50 ng/g,其中相对含量较高的PBDEs单体为BDE-28和BDE-47.鱼体内脏组织中PBDEs的检出水平较肌肉组织中的PBDEs要高,表明其更容易富集PBDEs.  相似文献   

6.
在对沉积物的修复技术中,原位覆盖技术能够降低污染物向水体的释放,降低污染物对底栖生物和水生生物的生物可利用性,以及能够减少污染物向下游的迁移.在本研究中,将活性炭添加到受HCHs、DDTs污染的沉积物中,考察了活性炭剂量、粒径以及活性炭与沉积物接触的方式对HCHs、DDTs水相平衡浓度的影响,及对半渗透膜(SPMD)吸...  相似文献   

7.
为系统了解太湖流域主要水源地有机氯农药(OCPs)污染情况,于2012年3月和6月采集太湖流域主要水源地水相、悬浮颗粒物和沉积物样品,并利用气相色谱(GC)—质谱(MS)联用仪对水源地OCPs的浓度水平进行监测分析。结果表明,3月水相和悬浮颗粒物中OCPs的质量浓度分别为4.03~18.70ng/L、ND(未检出)~27.60ng/g,高于6月的0.23~1.57ng/L、1.06~5.05ng/g。3月沉积物中仅有Y3采样点检出OCPs,而6月各采样点均有检出。6月水相中Y5、Y7和Y10采样点以α-六六六(α-HCH)为主,Y3和Y8采样点以γ-六六六(γ-HCH)为主,其余采样点均为β-六六六(β-HCH)占绝对优势;悬浮颗粒物中γ-HCH、α-HCH构成六六六(HCHs)的主要物质,而稳定性较高的β-HCH浓度却很低。与国内外研究比较,太湖流域水源地OCPs污染水平较低。大部分悬浮颗粒物中OCPs污染低于风险评价高值(ER-M),部分采样点高于风险评价低值(ER-L),表明存在一定的生态风险,需加强相关方面的防治工作。沉积物中污染物的浓度均低于ER-L,表明太湖流域沉积物的污染程度较低,在安全生态风险范围内。  相似文献   

8.
(汍)汊湖水体和表层沉积物中有机氯农药分布特征   总被引:1,自引:0,他引:1  
用GC/ECD内标法定量测定了(汍)汉湖水体和表层沉积物中的有机氯农药(OCPs).(汍)汊湖水样和表层沉积物中20种OCPs均有检出.表层沉积物上层中(0~2 cm)的OCPs明显高于下层(2~10 cm),这是(汍)汉湖具有稳定的水动力条件所致.氯丹在表层沉积物中浓度最高,与该化合物在环境中的强稳定性以及在该地区的大量使用有关.表层沉积物样品DCHsO2上层OCPs中o,p'-DDT主要成分,表明近期可能有新的DDTs,特别是含大量o,p'-DDT的三氯杀螨醇的使用.DDD/DDE则显示表层沉积物上层DDTs的降解主要处在厌氧条件下,而下层处在好氧条件下.  相似文献   

9.
广西岩溶地下河水体中有机氯农药浓度分布特征研究   总被引:4,自引:0,他引:4  
利用气相色谱检测器(GC-ECD)对广西典型岩溶区地下河水体中有机氯农药(OCPs)进行检测.结果表明:(1)广西典型岩溶区地下河水体中OCPs均有不同程度检出.岩溶地下河水体中OCPs质量浓度为0.09~16.17ng/L,均值为6.47 ng/L;水体中滴滴涕(DDTs)质量浓度为0.09~9.10 ng/L,均值...  相似文献   

10.
对台州湾近海5种不同生活习性的生物体内15种多环芳烃(PAHs)进行了分析,研究不同生物体对PAHs的富集规律,探讨生物体PAHs的积累量与栖息环境的关系.结果表明,蓝圆鲹(Decapterusmaruadsi)、红点圆趾蟹(Ovalipes punctatus)、海鳗(Muraenesox cinereus)、日本沙蚕(Nereis japomixaj)和棱鲻(Liza carimatus)体内15种PAHs的总质量浓度(∑PAHs)平均值分别为74.02、127.30、128.50、150.32、224.30 ng/g,棱鲻∑PAHs是蓝圆鲹∑PAHs的3倍,5种生物体内2环PAHs占∑PAHs的17.19%~28.89%,3环占31.74%~39.17%,4环占33.47%~44.52%,5环占1.99%~4.05%,6环占0.78%~2.50%,其中3环和4环所占的比例较高,6环最低.蓝圆鲹、棱鲻、海鳗、日本沙蚕、红点圆趾蟹对PAHs的富集系数分别为20.49、54.93、0.68、0.79、0.67,对PAHs富集系数最大的是棱鲻,最小的是红点圆趾蟹.底栖生物对高毒性的PAHs具有极强的富集能力,台州湾近海生物体内PAHs的积累量不仅与生物体自身的生活习性有关,还与其栖息环境密切相关.  相似文献   

11.
Gold (Au) accounts for only 0.004 g/ton of the earth's crust and is the most desired element. With an average annual world production of approximately 2,500 tons, the current methods of Au mining in developing countries cause major environmental issues. These issues vary from deforestation to cyanide and mercury (Hg) contamination. This article presents several cases of environmental catastrophes caused by Au mining in different regions of the world (Africa, the Middle East, Eastern Europe, and South America). It discusses the currently available processes for the large-scale extraction of metallic Au grains and supports the need for an alternative sustainable process.  相似文献   

12.
Diffuse reflectance spectroscopy can be successfully used for the quantitative determination of small amounts of pollutants like metals. The remission function was found to be linearly proportional to the concentration, when we applied the Kubelka–Munk equation. The color reactions of Cu(II), Co(II), and Ni(II) with dithiooxamide, were realised on filter paper. Reaction between Fe(III) and ammonium thiocyanate was realized on filter paper and gelatine matrix. All measurements were accomplished with a laboratory-constructed reflectometer. We have obtained a calibration curve by plotting the optical density of reflectance AR vs log of the mol l−1 concentration. Limits of detection at the 10−4 M level were estimated for all the compounds. Linear dynamic range extend over one order of magnitude and shows the potential of device for the quantitative analysis of environmental pollutants.  相似文献   

13.
The concentration profile of 40 polyfluoroalkyl substances (PFAS) in surface water along the River Rhine watershed from the Lake Constance to the North Sea was investigated. The aim of the study was to investigate the influence of point as well as diffuse sources, to estimate fluxes of PFAS into the North Sea and to identify replacement compounds of perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA). In addition, an interlaboratory comparison of the method performance was conducted. The PFAS pattern was dominated by perfluorobutane sulfonate (PFBS) and perfluorobutanoic acid (PFBA) with concentrations up to 181 ng/L and 335 ng/L, respectively, which originated from industrial point sources. Fluxes of ΣPFAS were estimated to be ∼6 tonnes/year which is much higher than previous estimations. Both, the River Rhine and the River Scheldt, seem to act as important sources of PFAS into the North Sea.  相似文献   

14.
Biodegradation of chlorobenzenes was assessed at an anoxic aquifer by combining hydrogeochemistry and stable isotope analyses. In situ microcosm analysis evidenced microbial assimilation of chlorobenzene (MCB) derived carbon and laboratory investigations asserted mineralization of MCB at low rates. Sequential dehalogenation of chlorinated benzenes may affect the isotope signature of single chlorobenzene species due to simultaneous depletion and enrichment of 13C, which complicates the evaluation of degradation. Therefore, the compound-specific isotope analysis was interpreted based on an isotope balance. The enrichment of the cumulative isotope composition of all chlorobenzenes indicated in situ biodegradation. Additionally, the relationship between hydrogeochemistry and degradation activity was investigated by principal component analysis underlining variable hydrogeochemical conditions associated with degradation activity at the plume scale. Although the complexity of the field site did not allow straightforward assessment of natural attenuation processes, the application of an integrative approach appeared relevant to characterize the in situ biodegradation potential.  相似文献   

15.
Raised beds are used to produce some high-value annual fruit and vegetable crops such as strawberry in California (CA) and tomato in Florida (FL), USA. Pre-plant soil fumigation is an important tool to control soil-borne pests in the raised beds. However, fumigant emissions have detrimental environmental consequences. Field trials were conducted to evaluate emissions of 1,3-dichloropropene (1,3-D) and chloropicrin (CP) in two different production systems with raised beds covered by different tarps. In the CA trial, InLine (60.8% 1,3-D and 33.3% CP) was drip-applied at 340 kg ha−1 to 5 cm deep in the beds (30 cm high and 107 cm wide) tarped with polyethylene (PE) or virtually impermeable film (VIF). In the FL trial, carbonated Telone C35 (63.4% 1,3-D and 34.7% CP) was shank-applied at 151 kg ha−1 to 20 cm deep in the beds (22 cm high and 76 cm wide) tarped with totally impermeable film (TIF). Emissions from tarped beds relative to furrows were contrary between the two trials. For the CA trial, the emission was 47% of applied 1,3-D and 27% of applied CP from PE tarped beds and 31% of applied 1,3-D and 15% of applied CP from VIF tarped beds, while that from uncovered furrows was <0.4% for both chemicals in both fields. In the FL trial, only 0.1% 1,3-D was emitted from the TIF tarped beds, but 27% was measured from the uncovered furrows. Factors contributing to the differences in emissions were chiefly raised-bed configuration, tarp permeability, fumigant application method, soil properties, soil water content, and fumigant carbonation. The results indicate that strategies for emission reduction must consider the differences in agronomic production systems. Modifying raised bed configuration and fumigant application technique in coarse textured soils with TIF tarping can maximize fumigation efficiency and emission reduction.  相似文献   

16.
In order to characterize the effect of vegetation on performance of constructed wetlands (CWs) treating low and high chlorinated hydrocarbon, two pilot-scale horizontal subsurface flow (HSSF) CWs (planted with Phragmites australis and unplanted) treating sulphate rich groundwater contaminated with MCB (monochlorobenzene, as a low chlorinated hydrocarbon), (about 10 mg L−1), and PCE (perchloroethylene, as a high chlorinated hydrocarbon), (about 2 mg L−1), were examined. With mean MCB inflow load of 299 mg m−2 d−1, the removal rate was 58 and 208 mg m−2 d−1 in the unplanted and planted wetland, respectively, after 4 m from the inlet. PCE was almost completely removed in both wetlands with mean inflow load of 49 mg m−2 d−1. However, toxic metabolites cis-1,2-DCE (dichloroethene) and VC (vinyl chloride) accumulated in the unplanted wetland; up to 70% and 25% of PCE was dechlorinated to cis-1,2-DCE and VC after 4 m from the inlet, respectively. Because of high sulphate concentration (around 850 mg L−1) in the groundwater, the plant derived organic carbon caused sulphide formation (up to 15 mg L−1) in the planted wetland, which impaired the MCB removal but not statistically significant. The results showed significant enhancement of vegetation on the removal of the low chlorinated hydrocarbon MCB, which is probably due to the fact that aerobic MCB degraders are benefited from the oxygen released by plant roots. Vegetation also stimulated completely dechlorination of PCE due to plant derived organic carbon, which is potentially to provide electron donor for dechlorination process. The plant derived organic carbon also stimulated dissimilatory sulphate reduction, which subsequently have negative effect on MCB removal.  相似文献   

17.
Background Scope and Aims. To realize the vision of sustainable development (SD) originating from the ‘only one earth’ philosophy, and to integrate the conceptions of ecology and sustainability into the planning and decision-making criteria of urban growth management, the establishment of a recycling-oriented society (ROS) is essential. However, before the above intention can be achieved, it is indispensable to develop a system of strategic indicators for supporting a radical reformation of the urban development plan. Therefore, this study, based on the conception of the new urban development pattern ROS, attempted to carefully choose a sample city in Taiwan for launching a preliminary case study, and furthermore designed and proposed a concise and strategy-oriented assessment indicator system termed ROSAIS. ROSAIS, on the one hand, can act as a compass for understanding resource using efficiency and recycling status during city development and, on the other hand, can serve as an implement supporting decision-making for ROS construction.Methods According to the definition and spirit of ROS, the structure of ROSAIS should clearly represent the relationship between resources and environment in human activities. The eco-efficiency indicator system (EEIS) and environmental symbiosis indicator system (ESIS) can be considered two key sub-indicator systems, and are the necessary components of ROSAIS. EEIS chooses the dominant production sectors in urban economic activities to calculate their eco-efficiency (EE). Separately, for obtaining a consensus regarding the framework of ESIS, the questionnaire approaches and expert consultation, together with the research experience and foundation of current relevant studies and indicator systems, are applied when crucial resource and environmental issues and respective indicators are selected.Results and Discussion The calculation results of EEIS in this case study indicated that among the three dominant production activities (agricultural, fishery, and animal husbandry sector) the fishery sector has the highest EE, which indicates that the fishery activities and resources significantly influence the sustainability of the economic-environmental system of the sample city. Furthermore, according to a consensus achieved in ESIS, local green spaces, resource recovery, energy consumption pattern change, freshwater conservation and greenhouse effect abatement were considered as the five crucial issues influencing how the case study city can develop into an ES-city. The rate of local green spaces, resource recycling, freshwater conservation and the rate of reduction of nonrenewable energy use as well as carbon dioxide (CO2) emissions were used to evaluate the above five issues.Conclusion This case study is unparalleled in Taiwan. Even in Japan, where ROS legislation has been implemented, this kind of study remains in the preliminary stages. Furthermore, when communicating the indicator results, it is essential to provide the context and countermeasures of the crucial issues that are faced. The two sub-indicator systems proposed in this case study could comply completely with the above-mentioned requirements. For example, the EEIS provides information for achieving a balance between environmental burden and economic benefits among dominant production sectors; the ESIS provides information for setting strategies for overcoming the crucial issues faced. Recommendation and Outlook This study recommends that urban planers should consider the construction of the corresponding strategic indicator system to be indispensable, and makes further use of the indicator results related to the environmental education of residents for identifying and promoting participation with ROS, and turning them into implements for supporting urban SD decision-making. Furthermore, a successful indicator system depends on data availability and quality. This study recommends that urban planers should pay considerable attention to constructing relevant data collection channels, databases and the data quality.  相似文献   

18.
通过网室盆栽试验,研究了施加磷矿粉(PR)、羟基磷矿粉(HA)、豆渣(SM)、骨碳(BC)及硫酸亚铁等土壤改良剂对油菜(Brassica oleracea L.)自铀矿区污染农田土壤吸收铀(238U)、镭(226Ra)及钍(232Th)的影响.结果表明,不同处理下油菜茎叶对238U、226Ra及232Th的富集系数分别在3.6×10-3~6.2×10-3、6.2×10-3~10.0×10-3及0.9×10-4~2.0×10-4之间.上述不同改良剂处理均能在一定程度上降低植物对238U、226Ra及232Th的吸收,以SM、HA处理效果较显著,其中SM处理下238U、226Ra及232Th的富集系数分别比对照降低42.9%、39%和71%.SM及HA对降低铀矿区污染土壤中植物对上述核素的吸收和富集具有潜在的应用价值.  相似文献   

19.
We investigated PCDDs and related compounds in the blood of young Japanese women, approximately 20 years of age, who had not yet had children, and discussed how the TEQ level of PCDDs and related compounds in their blood may affect the next generation. Means of total TEQ levels were 0.063 pg/g for whole blood basis and 21 pg/g for lipid basis. TEQ of PCDDs, PCDFs and coplanar PCBs accounted for about 43, 34 and 23% of the total TEQ in the whole blood basis, respectively. In the lipid basis, their values were about 44, 34 and 22%, respectively. Previously, we investigated PCDDs and related compounds levels in mother's breast milk, lymphocyte subpopulation and thyroid function of their children, and found negative correlations between the TEQ level of PCDDs and related compounds and CD4+/CD8+, and/or the TEQ level of PCDDs and related compounds and the T4 level in 36 mothers and children. Of these cases, the average age was approximately 28 years. PCDDs and related compounds may be related to immunopathy, such as atopic dermatitis. The effects of PCDDs and related compounds on babies of young Japanese women are important and must be further evaluated.  相似文献   

20.
The 6th Intergovernmental Negotiating Committee (INC 6), under the Stockholm Convention on POPs, gave an expert group the mandate to develop guidelines for the application and implementation of best available techniques (BAT) and best environmental practices (BEP) for the prevention and reduction of unintentionally produced and emitted POPs, including polychlorinated dibenzodioxins/-furans (PCDD/Fs), polychlorinated biphenyls (PCBs) and hexachlorobenzene (HCB). Measures to reduce or eliminate the release of these POPs to the environment can be found in Article 5 of the Convention. BAT and BEP are already being applied as emission reduction instruments in a number of industrialised countries and are elements of other major international treaties, e.g. the UN ECE Protocol on POPs and the Marine Convention's OSPAR and HELCOM, and of the EU Directive for Integrated Pollution Prevention and Control (IPPC Directive). Existing concepts are presented and compared with the requirements of the Stockholm Convention. Consequences, perspectives and questions for the future intersessional work of the above-mentioned Expert Group are discussed.  相似文献   

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