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1.
Comprehensive survey of major rivers in the Tokyo metropolitan area was conducted for clarifying the emission sources of perfluorooctane sulfonate (PFOS) in Tokyo. PFOS was found at all sampling sites at concentrations ranging from 0.5 to 58 ng L?1; in addition to this, it was also indicated that unknown PFOS emission sources are present in the midstream of the Tama River basin. The relationship between PFOS and perfluorooctanoic acid (PFOA) was constant at a ratio of 10:3 (PFOS/PFOA) throughout the Tama River basin. The sum of daily load amounts of PFOS from Tokyo’s major rivers to Tokyo Bay reached 215 g day?1. This value corresponds to 12.8 μg day?1 per person using the sum of wastewater treatment district populations. In contrast, an estimation of PFOS contribution of domestic wastewater was also attempted, and the contribution was 1.6 μg day?1 per person. We took samples up trunk sewers in the Tama River and finally found at the highest PFOS concentration (58,000 ng L?1) from one of the wastewater of the electronic parts manufacturing facilities.  相似文献   

2.
Poly- and perfluorinated alkyl substances (PFASs) are groups of persistent toxic substances that have been commonly detected in wastewater treatment plants (WWTPs). In some cases, the activated sludge (AS) in WWTPs will encounter special wastewaters containing PFASs up to tens of milligram per liter (mg L?1). However, under this condition, the potential impacts of PFASs on AS process remain unclear. In the present research, a lab-scale sequencing batch reactor was continuously exposed to perfluorooctanoic acid (PFOA), used as a representation for PFASs, at 20 mg L?1 to mimic the extreme condition. The objective is to explore the impact of PFOA on AS process in terms of its wastewater treatment performance and evolution of microbial communities. The results indicate that PFOA restrained the microbial growth and affected the dissolved organic carbon removal. These negative impacts could be recovered after long-term adaptation. Besides, 20 mg L?1 PFOA shows limited inhibition on nitrification and denitrification, suggesting a safe exposure level of PFOA for nitrogen removal. For microbial evolution, PFOA induced changes of communities during long-term exposure. The high abundance of Bacteroidetes, Proteobacteria, and Acidobacteria maintained over time reveals their tolerance towards PFOA. The occurrences of PFOA-resistant species are also observed. The present research provides new insight into the possible impacts of typical PFAS at high concentrations on AS process.  相似文献   

3.
Perfluorooctane sulfonate (PFOS) is one of the most widespread toxic substances in water distribution systems, posing a significant risk to public health and the environment due to its toxic and non-biodegradable nature. In this study, the effect of oxalate on PFOS adsorption/desorption to/from soil and sediment samples was studied with batch experiments. Dissolved organic carbon content in soil strongly enhanced the retention of organic halogens. Oxalate increased PFOS desorption by 1.43- to 17.14-fold and significantly increased the release of dissolved organic carbon and inorganic ions in soils. The effects of root exudates were similar to those of oxalate. Addition of low molecular weight dissolved organic carbon caused partial dissolution of the soil structure (e.g., through formation of organo-mineral complexes), resulting in the release of organic carbon and metal ions and subsequently enhancing PFOS desorption. The effects of oxalate on organic halogen desorption were influenced by dissolved organic carbon content and formation of calcium oxalate.  相似文献   

4.
全氟辛烷磺酸盐(PFOS)和全氟辛烷磺酸(PFOA)被使用50多年,污染已十分广泛,但它们的毒性机制仍不明确,尤其是基因毒性方面。本实验以三角涡虫为研究对象,采用单细胞凝胶电泳(single cell gel electrophoresis,SCGE,彗星实验)技术,探究PFOS和PFOA对细胞核DNA的损伤作用。结果显示PFOA能破坏核DNA,使其断裂,但PFOS不能破坏核DNA。另外,我们进一步提取纯化的大肠杆菌DNA与PFOS和PFOA共同孵育,以验证我们的实验结果,结果显示体外DNA实验与单细胞凝胶电泳检验结果一致。  相似文献   

5.
汤婕  张银龙 《土壤》2014,46(4):599-606
全氟辛酸(PFOA)和全氟辛烷磺酸(PFOS)在土壤/沉积物–水中分配、吸附–解吸作用是影响其在环境中的残留浓度、迁移、转化及生物可利用性、毒性等的重要因素之一。本文对土壤/沉积物中PFOA、PFOS吸附–解吸行为影响因素,吸附–解吸机理,常用的土壤/沉积物中PFOA、PFOS吸附/解吸等温线方程、常数及参数等的研究情况进行综述,吸附–解吸过程Freundlich方程的相关系数为0.74~0.99,线性方程的相关系数为0.91~0.99。PFOS在土壤/沉积物中吸附常数logKoc的平均值为3.0,变异系数为23.3%;解吸常数logKoc的平均值为1.8,变异系数为15.4%。PFOA在土壤/沉积物中吸附常数logKoc的平均值为2.1,变异系数为45.6%;解吸常数logKoc的平均值为5.4,变异系数为52.3%。实验室基础上计算所得吸附常数logKoc比野外条件下实测数据计算值(PFOA为3.7,PFOS为4.2)小,野外条件下土壤/沉积物中PFOA和PFOS吸附–解吸过程和土壤–植物共生系统对其污染控制效应有待于进一步研究。  相似文献   

6.
This study presents concentrations of perfluorinated compounds in food and the dietary intake of perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA) in The Netherlands. The concentrations of perfluorinated compounds in food were analyzed in pooled samples of foodstuffs randomly purchased in several Dutch retail store chains with nation-wide coverage. The concentrations analyzed for PFOS and PFOA were used to assess the exposure to these compounds in The Netherlands. As concentrations in drinking water in The Netherlands were missing for these compounds, conservative default concentrations of 7 pg/g for PFOS and 9 pg/g for PFOA, as reported by European Food Safety Authority, were used in the exposure assessment. In food, 6 out of 14 analyzed perfluorinated compounds could be quantified in the majority of the food categories (perfluoroheptanoic acid (PFHpA), PFOA, perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDA), perfluoro-1-hexanesulfonate (PFHxS), and PFOS). The highest concentration of the sum of these six compounds was found in crustaceans (825 pg/g product, PFOS: 582 pg/g product) and in lean fish (481 pg/g product, PFOS: 308 pg/g product). Lower concentrations were found in beef, fatty fish, flour, butter, eggs, and cheese (concentrations between 20 and 100 pg/g product; PFOS, 29-82 pg/g product) and milk, pork, bakery products, chicken, vegetable, and industrial oils (concentration lower than 10 pg/g product; PFOS not detected). The median long-term intake for PFOS was 0.3 ng/kg bw/day and for PFOA 0.2 ng/kg bw/day. The corresponding high level intakes (99th percentile) were 0.6 and 0.5 ng/kg bw/day, respectively. These intakes were well below the tolerable daily intake values of both compounds (PFOS, 150 ng/kg bw/day; PFOA, 1500 ng/kg bw/day). The intake calculations quantified the contribution of drinking water to the PFOS and PFOA intake in The Netherlands. Important contributors of PFOA intake were vegetables/fruit and flour. Milk, beef, and lean fish were important contributors of PFOS intake.  相似文献   

7.
PFOA对土壤酶活性的影响   总被引:2,自引:0,他引:2  
Perfluorooctanoic acid (PFOA) is a popular additive of the chemical industry; its effect on activities of important soil enzymes is not well understood. A laboratory incubation experiment was carried out to analyze the PFOA-induced changes in soil urease, catalase, and phosphatase activities. During the entire incubation period, the activities of the three soil enzymes generally declined with increasing PFOA concentration, following certain dose-response relationships. The values of EC 10 , the contaminant concentration at which the biological activity is inhibited by 10%, of PFOA for the soil enzyme activity calculated from the modeling equation of the respective dose-response curve suggested a sensitivity order of phosphatase > catalase > urease. The effect of PFOA on soil enzyme activities provided a basic understanding of the eco-toxicological effect of PFOA in the environment. Results of this study supported using soil phosphatase as a convenient biomarker for ecological risk assessment of PFOA-polluted soils.  相似文献   

8.
Perfluoroalkyl substances (PFASs), such as perfluorooctanoic acid (PFOA), are environmentally persistent industrial chemicals often found in biosolids. Application of these biosolids to pastures raises concern about the accumulation of PFOA in the edible tissues of food animals. Because data on the absorption, distribution, metabolism, and excretion (ADME) of PFOA in cattle were unavailable, a study was conducted to determine pharmacokinetic parameters following a single oral exposure (1 mg/kg body weight of (14)C-PFOA) in four Lowline Angus steers. Radiocarbon was quantified in blood, urine, and feces for 28 days and in tissues at the time of slaughter (28 days) by liquid scintillation counting (LSC) or by combustion analysis with LSC with confirmation by liquid chromatography-tandem mass spectrometry (LC-MS/MS). (14)C-PFOA was completely absorbed and excreted (100.7 ± 3.3% recovery) in the urine within 9 days of dosing. The plasma elimination half-life was 19.2 ± 3.3 h. No (14)C-PFOA-derived radioactivity was detected in edible tissues. Although PFOA was rapidly absorbed, it was also rapidly excreted by steers and did not persist in edible tissues, suggesting meat from cattle exposed to an acute dose of PFOA is unlikely to be a major source of exposure to humans.  相似文献   

9.
A vegetation study was carried out to investigate the carryover of Perfluorooctanoic Acid (PFOA) and Perfluorooctane Sulfonate (PFOS) from soil mixed with contaminated sewage sludge to potato, carrot, and cucumber plants. Analysis was done by liquid-extraction using acetonitrile with dispersive SPE cleanup and subsequent HPLC-MS/MS. In order to assess the transfer potential from soil, transfer factors (TF) were calculated for the different plant compartments: TF = [PFC](plant (wet substance))/[PFC](soil (dry weight)). The highest TF were found for the vegetative plant compartments with average values for PFOS below those for PFOA: cucumber, 0.17 (PFOS), 0.88 (PFOA); potato, 0.36 (PFOS), 0.40 (PFOA); carrot, 0.38 (PFOS), 0.53 (PFOA). Transfer of PFOA and PFOS into potato peelings (average values of TF: PFOA 0.03, PFOS 0.04) exceeded the carryover to the peeled tubers (PFOA 0.01, PFOS < 0.01). In carrots, this difference did not occur (average values of TF: PFOA 0.04, PFOS 0.04). Transfer of PFOS into the unpeeled cucumbers was low and comparable to that of peeled potatoes (TF < 0.01). For PFOA, it was higher (TF: 0.03).  相似文献   

10.
A study was undertaken to determine typical concentrations ofairborne bacteria in a local hospital in the tropicalenvironment of Singapore. Aerial sampling was conducted atvarious locations within the air-conditioned hospital buildingincluding the main lobby, a visitor restricted ward and apharmacy. Concentrations of airborne bacteria exceededavailable local guidelines for indoor air quality (i.e., 500colony forming units m-3 air in an air-conditionedenvironment) in the lobby and pharmacy, but not in the visitorrestricted ward. Results showed that the occupant density wasthe key factor influencing the level of airborne bacteria, buthumidity was also important depending on the particularlocation within the hospital. Bacteria identified wererepresentative of normal microflora of the skin, respiratoryand gastro-intestinal tracts, but also included theopportunistic pathogens Acinetobacter and Flavobacterium spp.  相似文献   

11.
[目的]对福建省的莆田东圳水库、福清东张水库、三明东牙溪水库水环境质量及预警等级进行评价,为湖泊(水库)水环境预警评价提供一种过程简单,结果科学合理的评价方法。[方法]根据韦伯—费希纳模型(Weber-Fechner’s model)的基本原理,以表征水库水环境的溶解氧(DO),化学需氧量(CODMn),总磷(TP),NH_3-N,总氮(TN)等参数作为评价指标,利用水环境综合指数ki来评价水库水环境质量及预警等级。[结果]莆田东圳水库2010年第1,2季度以及2012年第3季度处于中重警。福清东张水库2013年第3季度为轻警,2012年第1季度处于中重警。三明东牙溪水库2010年第4季度、2011第3季度、2012年第3季度、2013第3,4季度为轻警。其余季度上述水库水质预警等级为中警。[结论]韦伯—费希纳模型能够定量描述湖泊(水库)水环境质量的感觉强度变化关系,客观反映湖泊(水库)水环境质量变化的影响;该模型具有计算过程简单,评价精度高,应用性强等优点,为湖泊(水库)水质预警等级综合评价提供了新方法,拓展了评价模型的应用范围。  相似文献   

12.
The sorption behavior of sodium dodecylbenzene sulfonate (SDBS), an anionic surfactant, on marine sediments was systematically investigated. The experimental results showed that 100 min was required for the adsorption equilibrium. For the sediments treated by HCl and H2O, sorption behavior of SDBS was fit with linear isotherm very well over the concentration range studied at 298 K. The sorption occurred primarily due to partition function of hydrophobic chains into organic carbon of sediments. Sorption of SDBS on H2O2-treated sediments was satisfactorily fit with Freundlich isotherm model and mainly through surface function of clay minerals in the sediment. The sorption was favorably influenced by the increased salinity, deceased pH and decreased temperature of seawater.  相似文献   

13.
Soil enzymatic activities (phosphatases, arylsulphatase and dehydrogenase) were measured in microcosm systems designed for the study of the impact of a commercial mixture of Linear Alkylbenzene Sulphonate (LAS) homologues on a xerofluvent agricultural soil. The soil microcosms consisted of glass columns filled with 800 g of dry soil which were fed with sterile commercial LAS solutions at concentrations of 10 or 50 mg l−1 for periods of time up to 21 days. A soil microcosm fed with sterile distilled water was included in this study and considered as control. Our results showed that the continuous application of the anionic surfactant to soil increased the values of the enzymes acid and alkaline phosphatases and arylsulphatase. On the contrary, the dehydrogenase activity was decreased by the continuous application of 10 or 50 mg l−1 LAS when compared with control microcosms. In addition, a statistically negative correlation was found between this enzymatic activity in the upper portion of the soil columns amended with LAS and the viable counts of heterotrophic aerobic microorganisms. Moreover, in order to test the influence of LAS on nutrient availability and, consequently, on bacteria populations and soil biological activities, phosphate concentration was regularly determined in the microcosm leachates. The phosphate concentration tested in the leachate of the microcosm continuously amended with 50 mg l−1 LAS solution was significantly lower than the concentrations detected in the leachate of the microcosms continuously amended with 10 mg l−1 LAS throughout the experiment.  相似文献   

14.
广西南流江水土流失与水环境保护   总被引:1,自引:0,他引:1  
肖宗光 《水土保持研究》2000,7(3):157-158,207
通过水资源环境现状调查和分析,南流江水土流失严重,环境污染严重,加剧水环境的恶化。为此,提出综合防治流域水土流失的措施和对策,必须加强宣传,加强预防监督,增加治理投入,才能治理好南流江。  相似文献   

15.
中国水环境态势与方略   总被引:15,自引:0,他引:15  
由于过去人类水资源利用的不合理,目前我国水环境已经恶化到极其严重的地步。文章系统地分析了我国水系、湖泊、海域的水环境状况,并针对我国实际污染情况提出了相应的防治措施  相似文献   

16.
以中国工程院院士钱正英为组长开展的重大咨询项目“关于西北地区水资源配置、生态环境建设和可持续发展战略研究”,紧紧围绕西部大开发这一重大发展战略,抓住西北地区水资源配置、生态环境建设和可持续发展这一主题,开展了跨学科、跨部门的综合性、战略性研究,取得了重要成果。这一成果对于落实党的十六大报告提出的“积极推进西部大开发,促进区域经济协调发展”的要求和“打好基础,扎实推进,重点抓好基础设施和生态环境建设,争取十年内取得突破性进展”的目标,以及对西部地区经济社会可持续发展具有重要的指导意义。  相似文献   

17.
Anionic surfactants, the earliest and the most common surfactants in detergent and cosmetic product formulations contribute significantly to the pollution profile of the ecosystem. Linear alkylbenzene sulfonates (LAS), a major chemical constituent of detergents, forms an imperative group of anionic surfactants. Bioremediation of LAS by conventional processes such as activated sludge is ineffective due to the low kinetics of degradation by unsuitable organisms and foam production. Hence this study was focused on isolating and characterizing indigenous LAS-degrading bacteria from soil. Twenty different LAS-degrading bacteria were isolated from detergent-contaminated soil by enrichment culture technique and degradation efficiency was assessed by Methylene Blue Active Substances (MBAS) assay and by reverse-phase high-performance liquid chromatography (HPLC) analysis. The most efficient LAS-degrading isolates, L9 (81.33?±?0.7) and L12 (81.81?±?0.8), were selected and identified as Pseudomonas nitroreducens (MTCC 10463) and Pseudomonas aeruginosa (MTCC 10462). The 16S rDNA sequences of the isolates were deposited in NCBI GenBank under the accession numbers HQ 271083 (L9) and HQ 271084 (L12). The isolates were capable of degrading 0.05?g/l LAS at 25?°C and pH 7.0?C7.5. Presence of a solid support caused biofilm formation which in turn enhanced LAS degradation. The isolates tend to display diauxic growth with alternate carbon source such as dextrose. These isolates also have the capability to degrade other xenobiotics like hydrocarbons and pesticides. Since xenobiotic pollutants in nature occur as a mixture of compounds rather than single pollutants, the potential of these two indigenous LAS-degrading isolates to degrade multiple xenobiotics gains relevance.  相似文献   

18.
浅谈全球水资源态势和中国水资源环境问题   总被引:11,自引:0,他引:11  
石虹 《水土保持研究》2002,9(1):145-150
随着人口的不断增加,人类不但消耗大量水资源,而且还严重破坏资源环境,使全球及我国水资源量日益减少。在分析全球水资源态势的基础上,以可持续发展理论为指导,分析我国水资源现状,造成我国水资源短缺的主要原因是水资源环境破坏严重,指出我国实现水资源可持续利用的对策首先应大力植树种草和修复水资源环境,从而从根本上解决水资源短缺的问题。  相似文献   

19.
Aljustrel mining area is located in the Iberian Pyrite Belt, one of the greatest concentrations of massive sulphide deposits that extends from Lousal (Portugal) to Aznalcóllar (Spain). The surrounding streams, Roxo, Água Azeda and Água Forte, are influenced by the erosion of the tailing deposits and the input of acid mine drainage (AMD) from the abandoned Aljustrel pyrite mines, recently reopened in 2007. The purpose of this study was to understand how these adverse conditions influenced the stream sediments, water quality and periphytic diatom communities and establish the pre-restoration local conditions to judge the success of rehabilitation program now under way. For stream sediments, the highest metal concentration samples were found at sites F, G and H. Arsenic, Cu, Fe, Pb and Sb detected concentrations, generally exceeded the probable effect concentration values reaching level 4: the highest toxicity level. In surficial water samples of AMD affected sites (F, G and H), low pH values (1.5 to 3.5) and high metal concentrations of As (6,837 μg L?1), Cd (455 μg L?1), Cu (68,795 μg L?1), Fe (1,262,000 μg L?1), Mn (19,451 μg L?1), Pb (136 μg L?1), and Zn (264,377 μg L?1) were found. In these sites, the diversity index (H′) for diatoms was low (0.6 to 2.8) and the dominant taxa were Eunotia exigua (site F, 33.5%) and Pinnularia acoricola (abundances in sites: F, 86.8%; G, 88.5%; and H, 91.1%). In opposition, in less AMD impacted, H′ was high (1.5 to 4.6) and low metal concentrations and high pH were found. Achnanthidium minutissimum was the dominant taxon in (abundances in sites: A, 76.1% and B, 24.39%). Canonical correspondence analysis showed that spatial variation due to mine influence was more important than seasonal variation, which did not show any pattern.  相似文献   

20.
水环境的治理和保护是一项复杂的系统工程。本文在分析三明市水环境存在的主要问题的基础上,提出了解决水环境问题的对策措施。  相似文献   

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