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1.
Chlorinated ethenes such as trichloroethene (TCE), cis‐1,2‐dichloroethene (cis‐1,2‐DCE), and vinyl chloride along with per‐ and polyfluoroalkyl substances (PFAS) have been identified as chemicals of concern in groundwater; with many of the compounds being confirmed as being carcinogens or suspected carcinogens. While there are a variety of demonstrated in‐situ technologies for the treatment of chlorinated ethenes, there are limited technologies available to treat PFAS in groundwater. At a former industrial site shallow groundwater was impacted with TCE, cis‐1,2‐DCE, and vinyl chloride at concentrations up to 985, 258, and 54 µg/L, respectively. The groundwater also contained maximum concentrations of the following PFAS: 12,800 ng/L of perfluoropentanoic acid, 3,240 ng/L of perfluorohexanoic acid, 795 ng/L of perfluorobutanoic acid, 950 ng/L of perfluorooctanoic acid, and 2,140 ng/L of perfluorooctanesulfonic acid. Using a combination of adsorption, biotic, and abiotic degradation in situ remedial approaches, the chemicals of concern were targeted for removal from the groundwater with adsorption being utilized for PFAS whereas adsorption, chemical reduction, and anaerobic biodegradation were used for the chlorinated ethenes. Sampling of the groundwater over a 24‐month period indicated that the detected PFAS were treated to either their detection, or below the analytical detection limit over the monitoring period. Postinjection results for TCE, cis‐1,2‐DCE, and vinyl chloride indicated that the concentrations of the three compounds decreased by an order of magnitude within 4 months of injection, with TCE decreasing to below the analytical detection limit over the 24‐month monitoring period. Cis‐1,2‐DCE, and vinyl chloride concentrations decreased by over 99% within 8 months of injections, remaining at or below these concentrations during the 24‐month monitoring period. Analyses of Dehalococcoides, ethene, and acetylene over time suggest that microbiological and reductive dechlorination were occurring in conjunction with adsorption to attenuate the chlorinated ethenes and PFAS within the aquifer. Analysis of soil cores collected pre‐ and post‐injection, indicated that the distribution of the colloidal activated carbon was influenced by small scale heterogeneities within the aquifer. However, all aquifer samples collected within the targeted injection zone contained total organic carbon at concentrations at least one order of magnitude greater than the preinjection total organic carbon concentrations. 相似文献
2.
Sundström M Bogdanska J Pham HV Athanasios V Nobel S McAlees A Eriksson J DePierre JW Bergman Å 《Chemosphere》2012,87(8):865-871
Here, we describe for the first time the synthesis of [35S] PFOS and [35S] PFBS with sulfur-35 enriched sulfur dioxide as the radiolabelled reagent, resulting in 2.5 and 2.3 mCi of product, respectively. Basic information concerning the physicochemical properties of perfluorooctanesulfonate (PFOS), perfluorobutanesulfonate (PFBS) and perfluorooctanoic acid (PFOA) are still limited. Hence, we utilized these radiolabelled perfluoroalkanesulfonates (PFSAs), as well as carbon-14 labelled perfluorooctanoic acid ([14C] PFOA) to determine some basic characteristics of physiological and experimental significance.The solubility of PFOS in buffered aqueous solutions at pH 7.4 was found to be severely reduced in the presence of potassium and sodium ions, which, however, did not reduce the solubility of PFOA or PFBS. PFOS was found to adhere to a small extent to polypropylene and polystyrene, whereas no such adhesion of PFOA or PFBS was detected. The extents of adhesion of PFOS and PFOA to glass were found to be 20% and 10%, respectively. For the first time, the partition coefficients for PFOS, PFBS and PFOA between n-octanol and water were determined experimentally, to be −0.7, −0.3, and 1.4, respectively, reflecting the difference in the amphiphilic natures of these molecules. 相似文献
3.
Weinberg I Dreyer A Ebinghaus R 《Environmental pollution (Barking, Essex : 1987)》2011,159(1):125-132
To investigate waste water treatment plants (WWTPs) as sources of polyfluorinated compounds (PFCs), polybrominated diphenyl ethers (PBDEs) and synthetic musk fragrances to the atmosphere, air samples were simultaneously taken at two WWTPs and two reference sites using high volume samplers. Contaminants were accumulated on glass fiber filters and PUF/XAD-2/PUF cartridges, extracted compound-dependent by MTBE/acetone, methanol, or hexane/acetone and detected by GC-MS or HPLC-MS/MS. Total (gas + particle phase) concentrations ranged from 97 to 1004 pg m−3 (neutral PFCs), <MQL to 13 pg m−3 (ionic PFCs), 5781 to 482,163 pg m−3 (musk fragrances) and <1 to 27 pg m−3 (PBDEs) and were usually higher at WWTPs than at corresponding reference sites, revealing that WWTPs can be regarded as sources of musk fragrances, PFCs and probably PBDEs to the atmosphere. Different concentrations at the two WWTPs indicated an influence of WWTP size or waste water origin on emitted contaminant amounts. 相似文献
4.
Chang-Er Chen Yuanyuan Yang Sisi Liu Runmei Wang Cailin Li Jianhui Tang Tao Chen Guang-Guo Ying 《环境科学学报(英文版)》2022,34(11):90-97
The passive sampling technique, diffusive gradients in thin films (DGT) has attracted increasing interests as an in-situ sampler for organic contaminants including per- and polyfluoroalkyl substances (PFAS). However, its effectiveness has been questioned because of the small effective sampling area (3.1 cm2). In this study, we developed a DGT probe for rapid sampling of eight PFAS in waters and applied it to a water-sediment system. It has a much larger sampling area (27 cm2) and as a result lower method quantification limits (0.15 – 0.21 ng/L for one-day deployment and 0.02 – 0.03 ng/L for one-week deployment) and much higher (by > 10 factors) sampling rate (100 mL/day) compared to the standard DGT (piston configuration). The sampler could linearly accumulate PFAS from wastewater, was sensitive enough even for a 24 hr deployment with performance comparable to grab sampling (500 mL). The DGT probe provided homogeneous sampling performance along the large exposure area. The use of the probe to investigate distributions of dissolved PFAS around the sediment-water interface was demonstrated. This work, for the first time, demonstrated that the DGT probe is a promising monitoring tool for trace levels of PFAS and a research tool for studying their distribution, migration, and fate in aquatic environments including the sediment-water interface. 相似文献
5.
从跨学科研究的角度,以氟化工行业为例,探讨了全氟和多氟烷基物质(PFAS)和臭氧层消耗物质(ODS)两大类新污染物的共排放问题.从生产过程上解析两类物质的共生产机制,构建其内在联系;在排放途径上分析其差异性及交叉过程,剖析在样品采集、前处理和仪器分析方面所需的技术手段和挑战.在生态环境效应方面综合评估了两类污染物在不同介质中产生的生态和人群健康风险、臭氧层破坏和全球暖化效应.进一步拓展利益相关方分析、生命周期分析和质量平衡分析的视角,为新污染物共排放的研究和管理提供建议. 相似文献
6.
Sáez M de Voogt P Parsons JR 《Environmental science and pollution research international》2008,15(6):472-477
BACKGROUND, AIM, AND SCOPE: Perfluoroalkylated substances (PFAS) are chemicals with completely fluorinated alkyl chains. The specific properties of the F-C bond give PFAS a high stability and make them very useful in a wide range of applications. PFAS also pose a potential risk to the environment and humans because they have been recently characterized as persistent, bioaccumulative, and toxic. The objective of this work is to study the bacterial degradation of PFAS under aerobic and anaerobic conditions in municipal sewage sludge as a contribution toward understanding their environmental fate and behavior. MATERIALS AND METHODS: Bacterial communities from sewage sludge were exposed to a mixture of PFAS under aerobic or anaerobic conditions. Individual PFAS concentrations were determined in the experiment media at different exposure times using liquid chromatography-mass spectrometry analysis after extraction with solid-phase extraction. RESULTS: The PFAS analyses of samples of sludge showed repeatable replicate results, allowing a reliable quantification of the different groups of PFAS analyzed. No conclusive evidence for PFAS degradation was observed under the experimental conditions tested in this work. Reduction in concentrations, however, was observed for some PFAS in sludge under aerobic conditions. DISCUSSION: The largest concentration decrease occurred for the fluorotelomer alcohols (FTOHs), especially for the 8:2 FTOH, which have been described as biodegradable in the literature. However, this concentration decrease could be due to different causes: sorption to glass, septa, or matrix components, as well as bacterial activity. Therefore, it is not certain that biodegradation occurred. CONCLUSIONS: PFAS are very recalcitrant chemicals, especially when fully fluorinated. Although some decreases in concentration have been observed for some PFAS, such as the FTOHs, there is no conclusive evidence for biodegradation. It can be concluded that the PFAS tested in these experiments are non-biodegradable under these experimental conditions. RECOMMENDATIONS AND PERSPECTIVES: Since the presence of PFAS is ubiquitous in the environment and they can be toxic, more research is needed in this field to elucidate which PFAS are susceptible to biodegradation, the conditions required for biodegradation, and the possible routes followed. A possible inhibitory effect of PFAS on bacteria, the threshold concentrations, and conditions of inhibition should also be investigated. 相似文献
7.
本文通过文献梳理,分析了全(多)氟烷基化合物(PFAS)对植物的暴露途径;统计了已发表文献中36种植物对19种PFAS的转运、富集特征;系统地阐释了PFAS从环境介质到植物组织内的迁移、积累机制;讨论了PFAS分子结构(如全氟碳链长度、头部官能团)、植物生理特性、环境因素对该富集过程的影响,并提出了未来有关植物富集PFAS可关注的重点和方向,以期能深入认识PFAS在环境介质-植物根际-植物组织内的赋存与迁移转化特征,更好地管控评估PFAS污染场地并制定植物修复方案,为开展生态与健康风险评价提供参考。 相似文献
8.
AbstractPer- and polyfluoroalkyl substances, a group of fluoro-surfactants widely detected in the environment, wildlife, and humans, have been linked to adverse health effects. A growing body of literature has addressed their effects on obesity, diabetes and non-alcoholic fatty liver disease/non-alcoholic steatohepatitis. This review summarizes the brief historical use and chemistry of per- and polyfluoroalkyl substances, routes of human exposure, as well as the epidemiologic evidence for associations between exposure to per- and polyfluoroalkyl substances and the development of obesity, diabetes and non-alcoholic fatty liver disease/non-alcoholic steatohepatitis. We identified 22 studies on obesity and 32 studies on diabetes, while only 1 study was found for non-alcoholic fatty liver disease/non-alcoholic steatohepatitis by searching PubMed for human studies. Approximately two-third of studies reported positive associations between per- and polyfluoroalkyl substances exposure and the prevalence of obesity and/or type 2 diabetes. Causal links between per- and polyfluoroalkyl substances and obesity, diabetes and non-alcoholic fatty liver disease/non-alcoholic steatohepatitis, however, require further large-scale prospective cohort studies combined with mechanistic laboratory studies to better assess these associations. 相似文献
9.
全氟和多氟烷基化合物(perfluoroalkyl and polyfluoroalkyl substances,PFASs)是一类新兴持久性有机污染物.土壤中PFASs可以通过淋溶作用进入地下水影响水质安全,或者通过陆生食物链的传递和生物放大作用危害生态系统和人类健康,有关土壤中PFASs的赋存状况、浓度水平与行为机制的研究已经成为环境化学领域的热点之一.目前土壤中可以准确测定的PFASs在含氟化合物总量中的占比不到1%,含量为ng/g水平.我国相关研究主要集中在东部及氟化工厂周边地区,其组分以全氟辛烷磺酸(Perfluorooctane sulfonic acid,PFOS)和全氟辛酸(Perfluorooctanoic acid,PFOA)等长链PFASs为主.不同类型土壤中PFASs的赋存特征主要受到物质种类与土壤理化性质及周边人类活动的影响.除了含氟化学品生产和使用过程中的直接释放和大气传输以外,PFASs前体物在土壤环境中的转化也是其重要来源.吸附-解吸是PFASs在土壤中的主要归趋方式,化合物碳链长度及官能团种类、土壤理化性质和生物种类等因素都会影响其在土壤中的迁移转化和富集能力.鉴于目前的研究现状,需要进一步优化土壤中PFASs的提取和分析方法,关注新型PFASs在土壤中的变化趋势及行为机制,开展土壤中PFASs的生物可给性和生物可利用性研究,进一步评估PFASs的生态与人体健康风险. 相似文献
10.
大伙房水库属于全国城市供水九大重点水源地之一,作为辽宁省重要的饮用水水源地,库区水质直接影响该区域人民饮水安全及身体健康。对大伙房水库表层水体、沉积物和鱼类样品中全氟化合物(PFAS)的赋存特征及可能的来源进行分析,并运用健康风险商值法评估PFAS的潜在健康风险。结果表明,库区表层水体中ρ(ΣPFAS)为1.18~8.19 ng/L,主要污染物为全氟辛酸及其盐类化合物(PFOA)和全氟戊基羧酸(PFPA),其浓度水平随时间呈下降趋势;沉积物中只检出3种污染物,分别为PFOA、全氟十一烷基羧酸(PFUnA)和全氟十二烷基羧酸(PFDoDA),ω(ΣPFAS)为0.16~0.48 ng/g;不同鱼类样品中ω(ΣPFAS)由高到低依次为:武昌鱼(2.49 ng/g)>鲤鱼(2.30 ng/g)>白鲢(2.02 ng/g)>花鲢(2.01 ng/g),主要污染物均为PFPA。基于主成分分析与相关性分析可知,大伙房水库库区的PFAS主要来自采矿、电镀、涂料等工业污染废水和生活污水;健康风险评估结果表明,表层水体和鱼类样品中的PFAS不存在健康风险。 相似文献