The short-chain perfluorinated compounds PFBS,PFHxS, PFBA and PFHxA, disrupt human mesenchymal stem cell self-renewal and adipogenic differentiation

Per-and polyfluorinated alkyl substances(PFASs) are commonly used in industrial processes and daily life products.Because they are persistent, they accumulate in the environment, wildlife and humans.Although many studies have focused on two of the most representative PFASs, PFOS and PFOA, the potential toxicity of short-chain PFASs has not yet been given sufficient attention.We used a battery of assays to evaluate the toxicity of several four-carbon and six-carbon perfluorinated sulfonates and carboxyl acids(PFBS,PFHxS, PFBA and PFHxA), with a human mesenchymal stem cell(hMSC) system.Our results demonstrate significant cyto-and potential developmental toxicity for all the compounds analyzed, with shared but also distinct mechanisms of toxicity.Moreover, the effects of PFBS and PFHxS were stronger than those of PFBA and PFHxA, but occurred at higher doses compared to PFOS or PFOA.

Quantification of perfluorinated compounds in atmospheric particulate shows potential connection with environmental event

A method of quantification of perfluorinated compounds(PFCs)from atmospheric particulate matter(APM)is described.A single step pretreatment method,selective pressurized liquid extraction(SPLE),was developed to reduce the high matrix background and avoid contamination from commonly used multiple sample pretreatment steps.An effective sorbent was selected to purify the PFCs during SPLE,followed by liquid chromatography-tandem mass spectrometry(LC–MS/MS),for quantification of PFCs.Conditions affecting the SPLE efficiency,including temperature,static extraction time,and number of extraction cycles used,were studied.The optimum conditions were found to be 120℃,10 min,and 3 cycles,respectively.LC-MS/MS method was developed to obtain the optimal sensitivity specific to PFCs.The method detection limits(MDLs)were 0.006 to 0.48 ng/g for the PFCs studied and the linear response range was from 0.1 to 100 ng/g.To ensure accurate values were obtained,each step of the experiment was evaluated and controlled to prevent contamination.The optimized method was tested by performing spiking experiments in natural particulate matter matrices and good rates of recovery and reproducibility were obtained for all target compounds.Finally,the method was successfully used to measure 16 PFCs in the APM samples collected in Beijing over five years from 2015 to 2019.It is observed that some PFCs follow the trend of total PFC changes,and can be attributed to the environment influencing events and policy enforcement,while others don't seem to change as much with time of the year or from year to year.

Recent advances in electrochemical decontamination of perfluorinated compounds from water: a review

Per- and polyfluoroalkyl substances (PFAS) pose serious human health and environmental risks due to their persistence and toxicity. Among the available PFAS remediation options, the electrochemical approach is promising with better control. In this review, recent advances in the decontamination of PFAS from water using several state-of-the-art electrochemical strategies, including electro-oxidation, electro-adsorption, and electro-coagulation, were systematically reviewed. We aimed to elucidate their design principles, underlying working mechanisms, and the effects of operation factors (e.g., solution pH, applied voltage, and reactor configuration). The recent developments of innovative electrochemical systems and novel electrode materials were highlighted. In addition, the development of coupled processes that could overcome the shortcomings of low efficiency and high energy consumption of conventional electrochemical systems was also emphasized. This review identified several major knowledge gaps and challenges in the scalability and adaptability of efficient electrochemical systems for PFAS remediation. Materials science and system design developments are forging a path toward sustainable treatment of PFAS-contaminated water through electrochemical technologies.

Konjac-mulberry leaf compound powder alleviates OVA-induced allergic rhinitis in BALB/c mice

According to the proportion of 1:1, konjac flour and mulberry leaf powder are compounded into a kind of dietary fiber source(KMCP). It is found to be good for anti-inflammation. However, its precise anti-allergic rhinitis effect and mechanism remain unknown. In our work, the effect of KMCP on allergic rhinitis(AR)induced by ovalbumin(OVA)was investigated. We found that the number of nasal rubbing and sneezing, the eosinophil(EOS)count in the nasal mucosa, and the serum levels of histamine(HIS), OVA-specific immunoglobulin E(OVA-sIgE)and interleukin-4(IL-4)were decreased, and the histopathological changes of nasal mucosa were inhibited. Additionally, the experiments further proved that the KMCP treatment could exert substantial effects on short-chain fatty acids(SCFAs)metabolism in the cecum as well. Overall findings suggest that KMCP could suppress the inflammatory response in AR mice, and serve as a novel curative therapeutic for AR without side effects.

固相萃取结合高效液相色谱-串联质谱测定胎便中14种全氟和多氟烷基化合物

全氟和多氟烷基化合物(PFASs)是一类人工合成的物质,由于其热稳定、疏水、疏油等优良性质而被广泛使用于生活和生产中.PFASs具有环境持久性、生物累积性、多种毒性等特性,且可以通过胎盘屏障进入到胎儿体内,进而对胎儿健康产生潜在危害.胎便中积累了妊娠期间暴露于胎儿的外源性化合物,可用于监测PFASs对胎儿的宫内暴露特征.本研究基于固相萃取结合高效液相色谱-串联质谱技术,建立了胎便中14种PFASs的分析方法.采用乙腈/水(9∶1,V/V)对0.2 g冻干胎便样品进行超声提取,提取液经Envi-carb和Oasis WAX小柱固相萃取,0.1%氨甲醇洗脱.以10 mmol·L^(−1)乙酸铵水溶液和乙腈作为流动相对目标化合物进行梯度洗脱,采用Acquity UPLC BEH C18色谱柱进行分离,基于多反应监测负离子模式采集,内标法定量.结果表明,在2、5、20 ng·g^(−1)的加标浓度下,14种PFASs的回收率为65%—149%,相对标准偏差为3%—22%,方法检出限(MDLs)为0.001—0.149 ng·g^(−1),方法定量限(MQLs)为0.003—0.495 ng·g^(−1).使用该方法测定了10个胎便样品,ΣPFASs浓度范围为<MDLs—2.49 ng·g^(−1).该方法操作简单、便捷、灵敏度高且定量准确,为系统性研究胎便中PFASs的赋存特征及暴露风险提供了技术基础.

滤过型固相萃取柱净化-超高效液相色谱-串联质谱法测定鸡蛋中15种全氟化合物的含量

提出了滤过型固相萃取柱净化-超高效液相色谱-串联质谱法同时测定鸡蛋中全氟丁酸、全氟戊酸、全氟己酸、全氟庚酸、全氟辛酸、全氟壬酸、全氟癸酸、全氟十一酸、全氟十二酸、全氟十三酸、全氟十四酸、全氟丁烷磺酸、全氟己烷磺酸、全氟庚烷磺酸、全氟辛烷磺酸等15种全氟化合物含量的方法。鸡蛋样品(2 g)中加入0.1 mL 20.0μg·L^(-1)同位素内标混合溶液,经10 mL 80%(体积分数)乙腈溶液振荡和超声提取后,离心;分取5 mL滤液,直接过滤过型Captive EMR-Lipid柱净化,收集流出液,氮吹至近干,加入500μL甲醇复溶,经涡旋、离心处理后测定。采用Agilent Eclipse Plus C_(18)RRHD色谱柱(100 mm×2.1 mm,1.8μm)分离,以不同体积比的2 mmol·L^(-1)乙酸铵溶液和甲醇的混合溶液梯度洗脱,在电喷雾离子源负离子扫描模式下,以多反应监测模式检测,同位素内标法定量。结果表明:15种全氟化合物标准曲线的线性范围均为0.125~20.0μg·L^(-1),测定下限(10S/N)为0.05~0.16μg·kg^(-1);在0.500,4.00,16.0μg·kg^(-1)加标浓度水平下,15种目标物的回收率为78.0%~111%,测定值的相对标准偏差(n=6)为0.87%~14%。

高效液相色谱法检测水环境中全氟辛酸铵的研究

全氟辛酸铵(APFO)是一种难降解、生物积累和有毒的全氟和多氟烷基化合物(PFAS),对环境和生物健康构成严重威胁。虽然质谱法对PFAS的检测效果较好,但其成本高昂。高效液相色谱(HPLC)法是一种成本较低的检测方法,但现有的技术稳定性、重现性和效率较低。研究成功建立了一种以高氯酸水溶液和乙腈为流动相能够分离和检测APFO的HPLC法,系统探究了流动相体积比和pH对APFO检测的影响。结果表明,在高氯酸水溶液∶乙腈=60∶40,pH=3.5条件下呈现出最佳的APFO的出峰效果。该方法单样耗费时间少于15 min,检测限为1.01 mg/L,使用更简便的操作和花费更少的时间与成本达到了与其他HPLC方法相近的灵敏度,并在2~50 mg/L的浓度范围具有良好的线性。精密度和准确度实验结果表明,本方法相对标准偏差在9%以内,对实际水体的加标回收率在97.35%~104.80%之间,表现出对复杂样品测定的抗干扰性。本研究展示了该方法在水处理材料开发初期的实验环境中高效且经济地检测高浓度PFAS的巨大潜力。

京郊典型河流农用水中全氟化合物赋存特征、源解析及生态风险评估

为探究京郊典型河流农用水中全氟化合物(Perfluorinated Compounds,PFCs)污染特征及空间分布,以北京市郊区典型河流--通州区凉水河、房山区刺猬河-小清河的农用水为研究对象,共调查采集30个水体样品。采用超高效液相色谱-串联质谱分析方法对水体中PFCs的种类、浓度进行测定,并对其赋存特征及可能的来源进行分析,最终进行生态风险评估。结果表明:京郊典型河流农用水环境中PFCs种类较多且污染水平较低。通州区凉水河中检出11种PFCs,∑PFCs浓度范围为0~62.7 ng·L^(-1),最主要的PFCs为全氟丁烷羧酸(PFBA)、全氟己烷羧酸(PFHxA)、全氟辛烷羧酸(PFOA)。房山区刺猬河-小清河中21种PFCs全部被检出,∑PFCs浓度范围为0~93.1 ng·L^(-1),最主要的PFCs为全氟戊烷羧酸(PFPeA)、全氟十一烷羧酸(PFUnDA)和全氟十二烷磺酸(PFDoDs)。京郊典型河流农用水中PFCs污染的分布特征总体呈现上游高于下游的趋势,污染主要来自污水处理厂出水的排放和地表径流输入。生态风险评估表明,水体中PFCs的浓度均未达到对生态环境造成危害的水平。

高效液相色谱-串联质谱法测定医用口罩中8种全氟化合物

采用高效液相色谱-串联质谱(LC-MS/MS)技术建立了医用口罩中全氟辛酸、全氟辛烷磺酸钾、全氟十一酸、全氟十二酸、全氟辛烷磺酸胺、全氟十三酸、全氟十四酸、N-乙基全氟辛烷磺酸胺8种全氟化合物的测定方法。样品以甲醇为溶剂,超声提取,采用C_(18)(150 mm×2.1 mm,5μm)色谱柱分离,流动相为甲醇和乙酸铵,梯度洗脱,多反应监测(MRM)模式进行分析检测,外标法定量。结果表明:8种全氟化合物的定量限(LOQ,以信噪比>10计)为0.50~1.58μg/kg,在0.5~10μg/L时标准曲线线性关系良好(r>0.9979),样品加标回收率为98.4%~102.3%,相对标准偏差为1.55%~7.44%。该方法前处理简单,回收率高,精密度好,适用于医用口罩中全氟化合物的检测。

基于碳材料电增强吸附全氟化合物和抗生素的研究进展

新污染物以其持久性和生物富集性在环境中积累和迁移,对自然生态系统和人类健康造成巨大风险。电增强吸附可以通过控制外部施加不同电压有效吸附去除水体中的新污染物,并且再生简单、无二次污染,因此在去除新污染物等领域,电增强吸附技术有巨大的应用前景。碳材料具有比表面积大、导电性好、成本低等优点,是良好的电增强吸附电极材料。文章综述了近些年碳电极在电增强吸附部分重要新污染物(全氟化合物和抗生素)的研究进展,并探讨水环境条件对电增强吸附性能的影响。

水厂臭氧-生物活性炭工艺对短链PFCs及DOM去除特性的中试

全氟化合物(PFCs)在水环境中广泛分布并存在潜在毒性,活性炭吸附是目前被认为从饮用水中去除PFCs的有效技术之一。然而,关于臭氧-生物活性炭(O3-BAC)在实际水体中对短链PFCs去除特性的研究较少,因此在目前地表水环境中短链PFCs的污染水平不断升高的背景下,亟需评估该工艺的应用效果。文中以水厂砂滤产水为水源,研究了3种短链PFCs(PFBA、PFPeA、PFHxA)和溶解性有机物(DOM)在连续运行90 d的O3-BAC中试装置中的去除效果,同时探讨了关停臭氧和臭氧的投加量对短链PFCs和DOM去除效果的影响。结果表明,随着运行时间的延长,3种短链PFCs在O3-BAC中试中的去除率显著下降并且出现了PFCs穿透和解吸附现象,去除率下降程度为:PFBA>PFPeA>PFHxA,而DOM相关的DOC、UV_(254)和Φ_((T,n))指标的去除率下降程度则相对缓慢。臭氧的投加能够氧化DOM从而改善短链PFCs在炭滤中的吸附去除,关停臭氧后流入炭滤的DOM会抢占已吸附短链PFCs的吸附位点,使PFCs解吸附提前发生。过高的臭氧投加量又会使更具竞争性的低分子量有机物增多,从而削弱炭滤对短链PFCs的去除能力。

固相萃取-高效液相色谱-串联质谱检测污水中14种全氟化合物

本文建立了一种固相萃取-高效液相色谱-串联质谱(SPE-HPLC-MS/MS)同时测定水中全氟烷基羧酸(PFCAs)、全氟烷基磺酸(PFSAs)、全氟辛基磺酰胺(FOSAs)等14种全氟化合物及其前体物的分析方法,化合物通过多反应监测(MRM)模式检测,内标法定量。比较了不同种类溶剂的流动相、固相萃取柱类型对化合物峰形、响应和提取净化效率的影响。考察了方法的线性范围、检出限和测定下限、精密度及准确度。结果表明,水中14种全氟化合物及前体物在0.5~50μg·L^(-1)范围内线性关系良好,相关系数r大于0.999;在低、中、高3个添加水平下平均加标回收率为74.2%~112%,相对标准偏差为1.0%~17.3%,方法检出限和测定下限分别为0.5~2.4 ng·L^(-1)和2.0~9.6 ng·L^(-1)。应用本方法分析某污水厂进水、出水及中间工艺流程中的PFCs,发现均有不同程度的检出,检出率在71.4%~92.9%。其中PFOA,PFBS,PFHxA和PFHxS浓度最高,为33.9~150 ng·L^(-1)。本方法前处理简便、灵敏度高、重现性好,可同时检测水中多种全氟化合物及前体物,具有较好的实用性。

水环境中新污染物去除技术的研究进展

随着各类化学品大规模生产和使用,新污染物在环境中不断被发现。新污染物具有持久性和生物累积性,严重威胁生态环境安全和人体健康。目前,微塑料、抗生素、全氟化合物和内分泌干扰物是常见的4种新污染物。本文结合国内外研究进展,综述水环境中不同新污染物的去除技术,然后展望技术发展方向,旨在为水环境中新污染物的去除提供理论参考。

液相色谱-串联高分辨质谱法测定土壤和沉积物中17种全氟化合物

建立了超声提取-固相萃取/液相色谱-串联高分辨质谱同时测定土壤和沉积物中17种全氟化合物的检测方法。通过设计提取溶剂、超声温度、超声时间和超声次数对全氟化合物提取效率的正交试验,确定最优前处理条件为:样品过80目筛,在30℃下用甲醇超声提取30min,分离上清液并浓缩至1~2mL,加纯水稀释至200mL后过PWAX固相萃取柱净化,再用0.05%氨水-甲醇溶液进行洗脱,洗脱液浓缩定容后用AcclaimTM VANQUISH C18柱以2mmol/L乙酸铵溶液和乙腈为流动相进行梯度分离,高分辨质谱全扫描定量分析。结果表明,17种全氟化合物在1.0~20.0μg/L质量浓度范围内线性良好,相关系数r在0.997~0.9999范围内,方法检出限为0.1~0.3μg/kg,测定下限为0.4~1.2μg/kg,样品的加标回收率为96.8%~127%,相对标准偏差为0.8%~9.1%。该方法具有高效、灵敏、准确等优点,可同时监测土壤和沉积物中17种全氟化合物。

Perfluorinated compounds in blood of textile workers and barbers

12 perfluorinated compounds（PFCs） in human blood from workers in a textile mill in Shandong province and several barbershops in Tianjin were analyzed in this study. It was found that perfluorooctanesulfonate（PFOS） and perfluorooctanoate（PFOA） were the most prominent PFCs, with average concentrations of 5.73 mg/L and 5.46 mg/L for textile workers, and 2.55 mg/L and 2.84 mg/L for barbers.PFOS and perfluorohexanesulfonate（PFHxS） concentrations revealed a positive correlation in blood samples（p 〈 0.01）, and concentrations among PFOS, perfluorononanoic acid（PFNA） and perfluorodecanoic acid（PFDA） also revealed positive correlations（p 〈 0.01）. The influence of gender and age on PFC concentration in blood was also investigated, and the results showed that there was no statistically significant difference between the male and female samples, as well as in samples from people with different ages. Generally speaking, the textile workers

Evaluation of perfluorinated compounds in seven wastewater treatment plants in Beijing urban areas

The presence of perfluorinated compounds(PFCs)in seven major wastewater treatment plants(WWTPs)in Beijing was investigated in the current study.We detected nine PFCs in all the wastewater and sludge samples.Perfluorooctane acid(PFOA)is the dominant PFCs in influents and effluents,while perfluorooctane sulfonate(PFOS)is the major contaminant in sludge.The highest PFC concentration was found in plants at Qinghe and Jiuxianqiao WWTP,while the lowest was found at Fangzhuang WWTP.The total values of PFC range from 2.88 to 176 ng/L in influents,from 5.48 to 498 ng/L in effluents,and from 1.21 to 32.0 ng/g(dry wt)in sludge.The fact that effluents usually contain higher levels of PFCs than influents suggests that additional PFCs are produced during the wastewater treatment processes.However,PFOS decreases in effluents than in influents in 62%of the water samples.This may be due to the adsorption and removal of the sludge during the active process.Perfluoroalkyl carboxylates(PFCAs)were found significantly correlated with each other in the effluents,which may indicate their similar sources or the existence of their potential precursors in the wastewater or treatment processes.The mass flows of PFC discharges into WWTPs are 0.4–51.4 mg/day,and the mass flows of PFCs in effluents exceed those in influents by 127%.Domestic and commercial wastewaters are suggested to be the major sources of PFC pollution in WWTPs in Beijing.

Effect of co-existing organic compounds on adsorption of perfluorinated compounds onto carbon nanotubes

Co-existing organic compounds may affect the adsorption of perfluorinated compounds （PFCs） and carbon nanotubes in aquatic environments. Adsorption of perfluorooctane sulfonate （PFOS）, perfluorooctane acid （PFOA）, perfluorobutane sulfonate （PFBS）, and perfluor- ohexane sulfonate （PFHxS） on the pristine multi-walled carbon nanotubes （MWCNTs-Pri）, carboxyl functionalized MWCNTs （MWCTNs-COOH）, and hydroxyl functiona- lized MWCNTs （MWCNTs-OH） in the presence of humic acid, 1-naphthol, phenol, and benzoic acid was studied. Adsorption kinetics of PFOS was described well by the pseudo-second-order model and the sorption equilibrium was almost reached within 24 h. The effect of co-existing organic compounds on PFOS adsorption followed the decreasing order of humic acid 〉 1-naphthol 〉 benzoic acid〉phenol. Adsorbed amounts of PFOS decreased significantly in the presence of co-existing or preloaded humic acid, and both adsorption energy and effective adsorption sites on the three MWCNTs decreased, resulting in the decrease of PFOS adsorption. With increasing pH, PFOS removal by three MWCNTs decreased in the presence of humic acid and phenol. The adsorbed amounts of different PFCs on the MWCNTs increased in the order ofPFBS 〈 PFHxS 〈 PFOA 〈 PFOS. The increase of both initial concentrations and the number of aromatic rings of co-existing organic compounds suppressed PFOS adsorption on the MWCNTs.

Perfluorinated compounds in milk, milk powder and yoghurt purchased from markets in China

The exposure to perfluorinated compounds (PFCs) through the diet for humans is of great concern. Among the diet, dairy products are in great demand. This paper reports the study on the levels of 9 perfluorinated acids and 2 fluorotelomer acids in milk, milk powder and yoghurt purchased from Chinese markets from 2008 to 2009. The analytes were quantitated by high performance liquid chromatography/electrospray tandem mass spectrometry (HPLC-ESI-MS/MS). In milk samples, perfluoroheptanoic acid (PFHpA) and perfluorononanoic acid (PFNA) were detected frequently, both in 68% of samples. In milk powder samples, perfluorooctane sulfonate (PFOS), perfluorooctanoic acid (PFOA) and PFNA were the only detected PFCs and none of them was observed in more than 35% of samples. In yoghurt, PFOA was the most frequently detected compound, found in 69% of samples. None of fluorotelomer acids was observed in any samples. The mean concentrations of total PFCs were 178 pg/g (wet weight) in milk, 98 pg/g (dry weight) in milk powder and 42 pg/g in yoghurt (wet weight). It is notable that the data of this study indicate significant differences (P<0.001) among three kinds of packaging of milk in the concentration of total PFCs. A preliminary human health risk assessment of milk and dairy products consumption was conducted in this study. For adults, the mean daily intake of PFOS and total PFCs was equal to or lower than 23 and 167 pg kg-1 d-1 (body weight), respectively.

Process simulation and economic analysis of reactor systems for perfluorinated compounds abatement without HF effluent

New and efficient proposed to treat perfluorinated reactor systems were compounds via catalytic decomposition. One system has a single reactor （S-1）, and another has a series of reactors （S-2）. Both systems are capable of producing a valuable CaF2 and eliminating toxic HF effluent and their feasibility was studied at various temperatures with a commercial process simulator, Aspen HYSYS. They are better than the conventional system, and S-2 is better than S-1 in terms of CaF2 production, a required heat for the system, natural gas usage and CO2 emissions in a boiler, and energy consumption. Based on process simulation results, preliminary economic analysis shows that cost savings of 12.37% and 13.55% were obtained in S-2 at 589.6 and 621.4℃compared to S-1 at 700 and 750 ℃, respectively, for the same amount of CaF2 production.

Serum levels of perfluorinated compounds in the general population in Shenzhen, China

Perfluorinated compounds (PFCs) have been detected in many environmental matrices, biota, and nonoccupationally exposed populations in China recently. However, little is known about the distribution and levels of various PFCs in the general population living in areas where there is PFC exposure. In the present study, the levels and prevalence of ten target PFCs were determined in 227 serum samples from a population of nonoccupationally exposed individuals in Shenzhen, China. Results indicated that human exposure to PFCs was prevalent in Shenzhen. Perfluorooctanoate (PFOA) was the dominant PFC contaminant in the serum samples, with a median concentration of 6.72 ng/mL, followed by perfluorooctane sulfonate (PFOS) with a median concentration of 2.07 ng/mL. Other PFCs were detected at much lower concentrations, with median concentrations ranging from 0.02 to 0.87 ng/mL. Statistically, no significant (P>0.05) gender differences were observed for any of the PFCs. Significant (P<0.01) positive correlations were found between age and serum concentrations of the target PFCs, except for perfluorobutane sulfonate (R = 0.16, P = 0.01), perfluorohexanoic acid (R = 0.08, P = 0.22), and perfluoroheptanoic acid (R = 0.11, P = 0.10). Based on the one-compartment pharmacokinetic model, the total daily intakes of PFOA and PFOS for the general population in Shenzhen were calculated as 0.63 and 0.20 ng/kg body weight/day, respectively.