Abstract  In 2007 the Minnesota State Legislature passed Minnesota Statute 144.995 - 144.998, which established the Environmental Health Tracking and Biomonitoring (EHTB) program and directed the Minnesota Department of Health (MDH) to design and implement four pilot biomonitoring projects. The primary purpose of each of the pilot projects is to measure the range and distribution of a selected chemical or chemicals, in the body, in a community identified as likely to be exposed. Exposure is measured through the collection of a biological sample, such as blood or urine, from voluntary participants from the community. Another purpose of the pilot projects is to build biomonitoring capacity in the,sjare and-to .develop recommendations for the Legislature for the creation of an ongoing biomonitoring program in Minnesota. This biomonitoring pilot project, known as the East Metro PFC Biomonitoring Pilot Project, was designed to measure the range and distribution of 7 types of perfluorinated chemicals (PFCs) in 100 individuals from each of two separate communities. Contamination of drinking water supplies with PFCs in the east metro was discovered in the summer of 2004. MPCA and MDH collected water samples from private well owners as well as the Oakdale Municipal supply to assess and define the extent of the contamination. Routine monitoring was established by MDH and MPCA and actions to stop drinking water exposure were taken, including the provision ofbottled water, granular activated carbon (GAC) home filters, access to municipal water, and a water treatment plant that utilizes large GAC filters to remove PFCs for the Oakdale Municipal Water Supply'. With the implementation of these filtration practices, drinking water exposure in the community has been reduced to below established health-based values, and the plan for remediation of the contaminated waste facilities are currently underway which may further reduce the PFC exposure through drinking water.

Abstract  Perfluorononanoic acid (PFNA) and perfluorodecanoic acid (PFDA), which are classified as perfluoroalkyl and polyfluoroalkyl substances (PFASs), have been widely used in industrial applications as a surface protectant. PFASs have been detected in wildlife and in humans around the globe. The purposes of this study are to develop and validate a physiologically based pharmacokinetic (PBPK) model for detecting PFNA and PFDA in male and female rats, and to apply the model to a human health risk assessment regarding the sex difference. A PBPK model of PFNA and PFDA was established based on an in vivo study in male and female rats. Analytes in biological samples (plasma, nine tissues, urine, and feces) were determined by ultra-liquid chromatography coupled tandem mass spectrometry (UPLC-MS/MS) method. PFNA and PFDA showed a gender differences in the elimination half-life and volume of distribution. The tissue-plasma partition coefficients were the highest in the liver in both male and female rats. The predicted rat plasma and urine concentrations simulated and fitted were in good agreement with the observed values. The PBPK models of PFNA and PFDA in male and female rats were then extrapolated to a human PBPK model based on human physiological parameters. The external doses were calculated at 3.35 ng/kg/day (male) and 17.0 ng/kg/day (female) for PFNA and 0.530 ng/kg/day (male) and 0.661 ng/kg/day (female) for PFDA. Human risk assessment was estimated using Korean biomonitoring values considering the gender differences. This study provides valuable insight into human health risk assessment regarding PFNA and PFDA exposure.

Abstract  A method using liquid chromatography-tandem mass spectrometry (LC-MS/MS) with QuEChERS (quick, easy, cheap, effective, rugged, and safe) sample preparation was developed for the simultaneous determination of 12 perfluorocarboxylic acids (PFCAs) and 7 perfluorosulfonic acids (PFSAs) in the muscle of shrimp, shellfish, and fish. A modified QuEChERS procedure was applied to the extraction and concentration of perfluorinated compounds (PFCs) as well as for removal of interferences. The determination of the 19 PFCs was performed by LC-MS/MS in negative-ion detection mode. 13C-labeled PFCs, as a stable isotopic internal standard (except for L-PFBS, L-PFPeS, ipPFNS, and L-PFNS, for which no labeled analogs were available), was used for calibration. The limits of detection ranged from 0.01–1.0 μg/kg. The recoveries of spiked sample at 0.02–8.0 μg/kg ranged from 61 to 117% with relative standard deviations of less than 14%. The developed method was successfully utilized to monitor real samples, which demonstrated that it is a simple, fast, and robust method and could be used to monitor PFCAs and PFSAs in aquatic products. Most of the samples tested positive, mainly for perfluorooctane sulfonate acid (PFOS), perfluorooctanoic acid (PFOA), and perfluorobutanoic acid (PFBA), but other samples of the 14 studied PFCs were also present. © 2018, Springer Science+Business Media, LLC, part of Springer Nature.

Abstract  Oxygen sensing properties of optical sensor using layer of 1-pyrenedecanoic acid and perfluorodecanoic acid chemisorbed onto anodic oxidized aluminium plate was investigated. The ratio I-0/I-100, where I-0 and I-100 represent the detected fluorescence intensities from a substrate exposed to 100% argon and 100% oxygen, respectively, is used as an indicator of the sensitivity of the sensing film. The I-0/I-100 value of 1-pyrenedecanoic acid and perfluorodecanoic acid layer chemisorbed onto the anodic oxidized aluminium plate is estimated to be 18.6. On the other hand, the I-0/I-100 value of 1-pyrenedecanoic acid chemisorbed onto the anodic oxidized aluminiurn plate is 20.2. The response time of the 1-pyrenedecanoic acid layer is 8.5 s on going from argon to oxygen and the recovery time is 40 s on going from oxygen to argon, respectively. In contrast, the response and recovery times of the 1-pyrenedecanoic acid and perfluorodecanoic acid chemisorbed layer are 3.0 and 22 s, respectively. Thus, the optical oxygen sensor using 1-pyrenedecanoic acid and perfluorodecanoic acid chemisorbed layer has rapid response and recovery times. (C) 2003 Elsevier B.V. All rights reserved.

Abstract  Simultaneous exposure of Au and In2O3/SnO2 (ITO) electrodes to an equimolar solution of a thiol and a carboxylic acid or a thiol and phosphonic acid results in the selective attachment of the thiol to the Au electrode and the carboxylic or phosphonic acid to the ITO electrode. This selective surface-attachment chemistry is termed ''orthogonal self-assembly'' (OSA) and can be used to direct the spontaneous assembly of molecular reagents onto Au and ITO microstructures. The selectivity of the thiols for Au and the carboxylic or phosphonic acids for ITO:is determined by a combination of cyclic voltammetry experiments using ferrocene-tagged molecules, scanning Auger microscopy, and imaging secondary ion mass spectrometry (SIMS) to map the distribution of thiols, carboxylic acids, and phosphonic acids on derivatized Au and ITO microstructures. Simultaneous exposure of Au and ITO electrodes for 30 min to an equimolar solution of 11-mercaptoundecanoylferrocene (I) and 12-ferrocenyldodecanoic acid (III) results in a coverage ratio I:LII of approximately 100:1 on Au and 1:45 on ITO, as determined by cyclic voltammetry. A 30-min exposure of Au and ITO electrodes to an equimolar solution of I and 6-ferrocenylhexyl- phosphonic acid (V) yields a coverage ratio of I:V of 30:1 on Au and better than 1:100 on ITO. The coverages of I, III, and V on the Au and ITO electrodes can be determined using cyclic voltammetry by virtue of the difference in redox potential between the acylferrocene center in I and the alkylferrocene centers in III and V. Typical converages of I on Au (4 x 10(-10) mol/cm(2)) and PPI and V on ITO (6 x 10(-10) and 3 x 10(-10) mol/cm2, respectively) after 30 min of derivatization correspond to approximately a monolayer of redox-active molecules in each case. Long derivatization times' (12-15 h) result in small or insignificant changes in the coverage ratios of these reagents on both Au and ITO electrodes, demonstrating that the OSA is essentially complete within 30 min. Surface analysis by X-ray photoelectron spectroscopy, scanning Auger microscopy, and imaging SIMS of Au and ITO microstructures and Si3N4 surfaces exposed to equimolar solutions of I and perfluorodecanoic acid (IV), or 12,12, 12-trifluorodode-canethiol (II) and V, reveal the selective assembly of these reagents on the Au and ITO microstructures and their absence on the insulating Si3N4 substrate. The orthogonal self-assembly process described here provides a promising method by which individual molecules could be spontaneously oriented and connected between closely-spaced, externally-addressable electrodes.

Abstract  Since the approval of recombinant human insulin by FDA in 1982, more than 200 proteins are currently available for pharmaceutical use to treat a wide range of diseases. However, innovation is still required to develop effective approaches for drug delivery. Our aim is to investigate the potential use of fluorinated ionic liquids (FILs) as drug delivery systems (DDS) for therapeutic proteins. Some initial parameters need to be assessed before further studies can proceed. This work evaluates the impact of FILs on the stability, function, structure and aggregation state of lysozyme. Different techniques were used for this purpose, which included differential scanning fluorimetry (DSF), spectrophotometric assays, circular dichroism (CD), dynamic light scattering (DLS), and scanning and transmission electron microscopy (SEM/TEM). Ionic liquids composed of cholinium-, imidazolium- or pyridinium- derivatives were combined with different anions and analysed at different concentrations in aqueous solutions (below and above the critical aggregation concentration, CAC). The results herein presented show that the addition of ionic liquids had no significant effect on the stability and hydrolytic activity of lysozyme. Moreover, a distinct behaviour was observed in DLS experiments for non-surfactant and surfactant ionic liquids, with the latter encapsulating the protein at concentrations above the CAC. These results encourage us to further study ionic liquids as promising tools for DDS of protein drugs.

Abstract  The mass spectra of the controlled substance 3,4-MDMA and its regioisomer 2,3-MDMA are characterized by an imine fragment base peak at m/z 58 and additional fragments at m/z 135/136 for the methylenedioxybenzyl cation and radical cation, respectively. Three positional ring methoxy isomers of N-methyl-2-(methoxyphenyl)-3-butanamine (MPBA) have an isobaric relationship to 2,3- and 3,4-MDMA. All five compounds have the same molecular weight and produce similar EI mass spectra. This lack of mass spectral specificity for the isomers in addition to the possibility of chromatographic co-elution could result in misidentification. The lack of reference materials for the potential imposter molecules constitutes a significant analytical challenge. Perfluoroacylation of the amine group reduced the nitrogen basicity and provided individual fragmentation pathways for discrimination among these compounds based on unique fragment ions and the relative abundance of common ions. Studies using gas chromatography with infrared detection provided additional structure-IR spectra relationships. The underivatized amines and the perfluoroacylated derivatives (PFPA and HFBA) were resolved by capillary gas chromatography on a 100% dimethylpolysiloxane stationary phase. The perfluoroacylated derivatives showed better resolution on a cyclodextrin modified stationary phase.

Abstract  Mass spectral differentiation of 3,4-methylenedioxymethamphetamine (3,4-MDMA), a controlled drug, and its 2,3-regioisomer from the ring substituted ethoxyphenethylamines is possible after formation of the perfluoroacyl derivatives, pentafluoropropionamides (PFPA), and heptafluorobutyrylamides (HFBA). The ring substituted ethoxyphenethylamines constitute a unique set of compounds having an isobaric relationship with 3,4-MDMA. These isomeric forms of the 2-, 3-, and 4-ethoxy phenethylamines have mass spectra essentially equivalent to 3,4-MDMA; all have molecular weight of 193 and major fragment ions in their electron ionization mass spectra at m/z 58 and 135/136. All the side chain regioisomers of 2-ethoxy phenethylamine having equivalent mass spectra to 3,4-MDMA are synthesized and compared via gas chromatography-mass spectrometry to 2,3- and 3,4-methylenedioxymethamphetamine. The mass spectra for the perfluoroacyl derivatives of the primary and secondary amine regioisomers are significantly individualized, and the side chain regioisomers yield unique hydrocarbon fragment ions at m/z 148, 162, and 176. Additionally, the substituted ethoxymethamphetamines are distinguished from the methylenedioxymethamphet-amines via the presence of the m/z 107 ion. Gas chromatographic separation on relatively non-polar stationary phases successfully resolves these derivatives.

Abstract  Five side chain regioisomers of 2-methoxy-4-methylphenethylamine constitute a unique set of compounds having an isobaric relationship with the controlled drug substance 3,4-methylenedioxymethamphetamine (3,4-MDMA or Ecstasy). These isomeric forms of the 2-methoxy-4-methyl-phenethylamines have mass spectra essentially equivalent to 3,4-MDMA; all have molecular weight of 193 and major fragment ions in their electron ionization mass spectra at m/z 58 and 135/136. Mass spectral differentiation of 2,3 and 3,4-MDMA from primary and secondary amine regioisomeric side chains of 2-methoxy-4-methyl-phenethylamines was possible after formation of the perfluoroacyl derivatives, pentafluoropropionamides (PFPA) and heptafluorobutyrylamides (HFBA). The mass spectra for these derivatives are individualized and the resulting unique fragment ions allow for specific side-chain identification. The individualization is the result of fragmentation of the alkyl carbon-nitrogen bond yielding unique hydrocarbon fragments of varying mass. Gas chromatographic separation on relatively non-polar stationary phases gave essentially base line resolution for these compounds.

Abstract  A gas chromatography/mass spectrometry (GC/MS) method is described which uses negative ion chemical ionization (NCI) and tandem mass spectrometry (MS/MS) for the determination of eight anabolic steroids in human urine. Eight anabolic steroids were derivatized by heptafluorobutyric anhydride (HFBA), and were determined using GC/NCI-MS and GC/NCI-MS/MS. The linear correlation coefficients for calibration in NCI-MS/MS were in the range 0.9880-0.9988. This method of derivatization with HFBA for use with GC/NCI was useful in determinations of 19-norandrosterone, boldenone, 19-noretiocholanolone, 2-methylandrosterone, nandrolone, 1-methyleneandrosterone, 1-methylandrosterone, 4-dihydroboldenone and mesterolone. The detection limits of this procedure were 5-20 ppb at a signal-to-noise (S/N) ratio of 3.

Abstract  The gaseous fluorocarbon trifluoromethane has recently been investigated for its potential as an in vivo gaseous indicator for nuclear magnetic resonance studies of brain perfusion. Trifluoromethane may also have significant value as a replacement for chlorofluorocarbon fire retardants. Because of possible species-specific cardiotoxic and anesthetic properties, the toxicological evaluation of trifluoromethane in primates (Papio anubis) is necessary prior to its evaluation in humans. We report the acute cardiac and central nervous system effects of trifluoromethane in eight anesthetized baboons. A dose-response effect was established for respiratory rate, electroencephalogram, and cardiac sinus rate, which exhibited a stepwise decrease from 10% trifluoromethane. No spontaneous arrhythmias were noted, and arterial blood pressure remained unchanged at any inspired level. Intravenous epinephrine infusions (1 microgram/kg) induced transient cardiac arrhythmia in 1 animal only at 70% FC-23 (v/v) trifluoromethane. Trifluoromethane appears to induce mild dose-related physiological changes at inspired levels of 30% or more, indicative of an anesthetic effect. These data suggest that trifluoromethane may be safe to use in humans, without significant adverse acute effects, at an inspired level of 30%.

Abstract  Using methyl methacrylate (MMA), butyl acrylate(BA) and hexafluorobutyl acrylate(HFBA) as main raw materials, we prepared self-crosslinked fluorocarbon polymer emulsion with core-shell structure via soap-free emulsion polymerization when the conception of particle design and polymer morphology was adopted. Moreover, the influence of mole ratio of BA to MAA, pH value on the oligomer was studied. And the effects of the added amount of oligomer, self-crosslinked monomer and HFBA, mass ratio of BA to MMA, reaction temperature and the initiator on the polymerization technology and the performance of the product, were investigated and optimized. The structure and performance of the fluorocarbon polymer emulsion were characterized and tested with FTIR, TEM, MFT and contact angle and water absorption of the latex film. The experimental results show that the optimal conditions for preparing fluorocarbon polymer emulsion are as follows: for preparing the oligomer, mol ratio of BA to MAA is equal to 1.0: 1.60, and pH value is controlled within the range of 8.0 and 9.0; for preparing fluorocarbon polymer emulsion, the added amount of oligmer[P(BA/MANa)] is 6%; mass ratio of BA to MMA is 40: 60; the added amount of self-crosslinked monomer is 2%, the added amount of HFBA is 15%; reaction temperature is 80 A degrees C; the mixture of potassium persulfate and sodium bisulfite is used as the initiator. The film-forming stability of the fluorocarbon polymer emulsion and the performance of the latex film, which is prepared with the soap-free emulsion polymerization, are better than that prepared with the conventional emulsion polymerization.

Abstract  For the first time, through macromonomer radical copolymerization, a novel fluorinated polyurethane (FPU) was synthesized based on partly acrylate-endcapped polyurethane macromonomers with hexafluorobutyl acrylate (HFBA). Partly acrylate-endcapped polyurethane (PU) macromonomers were synthesized using isophronediisocyanate (IPDI), dimethylol propionic acid (DMPA), polyethylene adipate glycols (PEA) etc. The novel fluorinated polymer, which bore PU side chains and fluorinated side chains, was confirmed by F-19 NMR spectroscopy, X-ray photoelectron spectroscopy (XPS), elemental analysis, scanning electron spectroscopy (SEM) etc. Copolymerization of polyurethane macromonomers with hexafluorobutyl acrylate (HFBA) was briefly investigated. The surface tension of FPU solution was measured and showed sharply decrease compared to that of pure polyurethane. Results from SEM showed a uniform size distribution of phase micro-domains on the fracture surface of FPU. (c) 2005 Elsevier Ltd. All rights reserved.

Abstract  Block copolymers (BCPs) consisting of fluorinated and non-fluorinated blocks can show interesting morphology, because of the presence of two dissimilar blocks. In this investigation BCPs of methyl methacrylate (MMA) and 2,2,3,3,4,4,4-heptafluorobutyl acrylate) (HFBA), (PMMA-b-PHFBA) were synthesized via reversible addition fragmentation chain-transfer (RAFT) polymerization using 2-cyano-2-propyl dithiobenzoate (CPBT) as chain transfer agent (CTA). Gel permeation chromatography (GPC) and H-1 NMR analyses confirmed the synthesis of well-defined BCP. TEM and XRD analyses showed lamellar stacking in the BCP. Surface morphology and topography of the BCP were analyzed by SEM and AFM analyses. The morphology of the BCP in THE and methyl ethyl ketone (MEK) solvent mixture was studied by TEM analysis. Morphology of the BCP varied from lamellar to spherical micelles with the variation of THE-MEK ratio in the solution, as evidenced by TEM and DLS analyses. (C) 2016 Elsevier B.V. All rights reserved.

Abstract  The commercial hyperbranched aliphatic polyols (Hn) were modified by thioglycolic acid (TA) and hexafluorobutyl acrylate (HFBA) or dodecafluoroheptyl methacrylate (DFHMA) to prepare a series of fluorinated hyperbranched polyesters. For comparison, a linear fluorinated polymer, poly(n-BMA-co-DFHMA), was synthesized through the copolymerization of n-butyl methacrylate (BMA) and DFHMA. The molecular structures were characterized by (1)H NMR spectroscopic analysis. The synthesized polymers were incorporated into UV-curable formulations as additives, and exposed to a UV lamp. After UV curing, the wettability of the films was investigated by contact angle measurement with water and bromonaphthalene. The results showed that both the hydrophobicity and oleophobicity were greatly enhanced. Moreover, the fluorinated hyperbranched polymers possessed better water and oil repellency than the copolymer poly(n-BMA-co-DFHMA) at a very low concentration. The surface F/C ratio values of the cured films were detected by XPS analysis, and the film with TAH20-DFHMA showed the highest F/C ratio value, indicating its most efficient aggregation effect at the film surface. (C) 2010 Elsevier B.V. All rights reserved.

Abstract  A comparison study of derivatization reactions for determining aniline (62533) and chlorinated anilines by gas chromatography was conducted. Aniline and 16 chloroanilines were reacted with trifluoroacetic-anhydride (TFAA), pentafluoropropionic-anhydride, heptafluorobutyric-anhydride (HFBA), chloroacetic-anhydride, or dichloroacetic-anhydride (DCAA). The derivatives were analyzed by capillary gas chromatography with electron capture detection or gas chromatography/electron impact mass spectrometry (GC) to determine which derivatization technique was the most suitable. TFAA reacted the fastest. The TFAA reaction was complete within 5 minutes at room temperature except in the case of pentachloroaniline (527208) and 2,3,5,6-tetrachloroaniline (3481207) which were 70 and 85 percent completed after 5 minutes, respectively. HFBA reacted quantitatively with all the anilines; however, it was the slowest, requiring 18 hours at room temperature. The HFBA reactions were completed within 30 minutes if the reaction mixtures were heated to 60 degrees-C. The HFBA and DCAA derivatives were completely separated by gas chromatography and they produced intense molecular ions or characteristic ions that could be readily quantitated by GC/EIMS. Side products produced in the reaction mixture interfered with the analysis of the DCAA derivatives. Even though they were formed the fastest, the TFAA derivatives did not have the necessary sensitivity to be detected by the gas chromatography detector. The gas chromatographic detection limits for the HFBA derivatives ranged from 0.1 to 0.3 picograms (pg) and the calibration curve was linear over the range 10 to 250pg per microliter. The author concludes that the HFBA reaction is the derivatization technique of choice for the anilines examined.

Abstract  The spatial and temporal distribution of per- and polyfluoroalkyl substances (PFASs) in the open Western Mediterranean Sea waters was investigated in this study for the first time. In addition to surface water samples, a deep water sample (1390 m depth) collected in the center of the western basin was analyzed. Perfluorohexanoic acid (PFHxA), perfluoroheptanoic acid (PFHpA), perfluorooctanoic acid (PFOA), perfluorohexanesulfonate (PFHxS) and perfluorooctanesulfonate (PFOS) were detected in all samples and were the dominant PFASs found. The sum of PFAS concentrations (ΣPFASs) ranged 246-515 pg/L for surface water samples. PFASs in surface water had a relatively homogeneous distribution with levels similar to those previously measured in the Atlantic near the Strait of Gibraltar, in water masses feeding the inflow to the Mediterranean Sea. Higher concentrations of PFHxA, PFHpA and PFHxS were, however, found in the present study. Inflowing Atlantic water and river/coastal discharges are likely the major sources of PFASs to the Western Mediterranean basin. Slightly lower (factor of 2) ΣPFASs was found in the deep water sample (141 pg/L). Such a relatively high contamination of deep water is likely to be linked to recurring deep water renewal fed by downwelling events in the Gulf of Lion and/or Ligurian Sea.

Abstract  Decomposition of perfluorinated chemicals is of significant interest in both scientific and industrial perspectives. Here, we report the decomposition of perfluorooctanoic acid (PFOA) under sonication-assisted photocatalysis by utilizing commercial TiO(2) (RdH) and home-made TiO(2) (sol-gel) as photocatalysts at ambient temperature, pressure and near neutral pH with the irradiation of 254nm UV light. PFOA was decomposed into fluoride ions and to several perfluorinated carboxylic acids (PFCAs) with a shorter carbon chain length such as perfluoroheptanoic acid (PFHpA), perfluorohexanoic acid (PFHxA), perfluoropropanoic acid (PFPA), and trifluoroacetic acid (TFA). The efficiency of sonication-assisted photocatalysis was found to be 64%. In all the cases, higher efficiencies were obtained when sol-gel TiO(2) was used as a photocatalyst than the commercial RdH TiO(2) catalyst. The specific surface area is three times higher for sol-gel TiO(2) than commercial RdH TiO(2) and appears to be the probable reason for the observed differences in the corresponding efficiencies. It is also interesting to note that pH plays a determining role in the decomposition of PFOA and correspondingly photocatalyses were carried out under different controlled pH. Perfluoroalkyl radicals are presumably oxidized by superoxide and hydroxyl radicals generated during the TiO(2)-mediated photocatalysis at pH 4 and 10, respectively. The role of sonication in sonication-assisted photocatalysis was construed to be an aid to photocatalysis than a tool itself. Sonication enhances photocatalysis through physical dispersion of TiO(2) and eases mass transfer which keeps on rejuvenating the TiO(2) surface.

Abstract  The aim of this study was to investigate 12 perfluorinated compounds (PFCs) including perfluorinated carboxylates (C4-C12) and perfluorinated alkyl sulfonates (C4, C6, and C8) in river and seawater samples to determine contamination levels in the aquatic environment of Hyogo prefecture, Japan. High levels of perfluorohexanoic acid (PFHxA; 2300-16,000 ng/L) were detected in the Samondogawa River at Tatsumi Bridge downstream of a PFC production facility; this location also had the highest mass flow rate of PFCs (3900-29,000 kg/y). Widespread contamination of coastal waters was confirmed with PFHxA as the dominant compound. Perfluorooctanoic acid was also prevalent in coastal waters. The concentration of PFHxA in coastal seawater and the distance from the mouth of the Samondogawa River were inversely related. This discharge of high concentrations of PFHxA from the Samondogawa River may have affected concentrations of PFCs in Osaka Bay.

Abstract  The sorption and desorption behaviors of two perfluoroalkane sulfonates (PFSAs), including perfluorohexane sulfonate (PFHxS) and perfluorooctane sulfonate (PFOS) on two humic acids (HAs) and humin (HM), which were extracted from a peat soil, were investigated. The sorption kinetics and isotherms showed that the sorption of PFOS on the humic substances (HSs) was much higher than PFHxS. For the same PFSA compound, the sorption on HSs followed the order of HM>HA2>HA1. These suggest that hydrophobic interaction plays a key role in the sorption of PFSAs on HSs. The sorption capacities of PFSAs on HSs were significantly related to their aliphaticity, but negatively correlated to aromatic carbons, indicating the importance of aliphatic groups in the sorption of PFSAs. Compared to PFOS, PFHxS displayed distinct desorption hysteresis, probably due to irreversible pore deformation after sorption of PFHxS. The sorption of the two PFSAs on HSs decreased with an increase in pH in the solution. This is ascribed to the electrostatic interaction and hydrogen bonding at lower pH. Hydrophobic interaction might also be stronger at lower pH due to the aggregation of HSs.

Abstract  Poly- and perfluoroalkyl substances (PFASs) are a class of fluorinated chemicals that are utilized in firefighting and have been reported in groundwater and soil at several firefighter training areas. In this study, soil and groundwater samples were collected from across a former firefighter training area to examine the extent to which remedial activities have altered the composition and spatial distribution of PFASs in the subsurface. Log Koc values for perfluoroalkyl acids (PFAAs), estimated from analysis of paired samples of groundwater and aquifer solids, indicated that solid/water partitioning was not entirely consistent with predictions based on laboratory studies. Differential PFAA transport was not strongly evident in the subsurface, likely due to remediation-induced conditions. When compared to the surface soil spatial distributions, the relative concentrations of perfluorooctanesulfonate (PFOS) and PFAA precursors in groundwater strongly suggest that remedial activities altered the subsurface PFAS distribution, presumably through significant pumping of groundwater and transformation of precursors to PFAAs. Additional evidence for transformation of PFAA precursors during remediation included elevated ratios of perfluorohexanesulfonate (PFHxS) to PFOS in groundwater near oxygen sparging wells.

Abstract  In Cologne, Germany, increased concentrations of perfluorinated compounds (PFC) have been observed in two private wells used for drinking water purposes. Both wells are located in the vicinity of a fire training area. Use of well water as a source of drinking water was prohibited by the Public Health Department of the City of Cologne. A human biomonitoring (HBM) survey was performed among all persons, who consumed water from these private wells (N=10). PFC concentrations in water of the private wells and in blood samples were analysed by tandem mass spectrometry with electrospray ionization (LC-ESI-MS/MS). Repeated water analyses (seven measurements between December 2009 and November 2010) indicated a decrease of PFOS from 8.35 to 1.60 μg/l, (PFHxS: 2.36-0.15 μg/l; PFOA: 0.16-0.03 μg/l) in one private well. Although situated close together, PFC-concentrations in the other private well were significantly lower. PFOS-concentrations in blood samples of private well water consumers ranged from 4.8 to 295 μg/l (PFHxS: 12.1-205 μg/l; PFOA: 4.0-18 μg/l). Although no data on the formulation of the firefighting foams applied on the fire training area is available, firefighting foams are supposed to be the most likely source of contamination. These findings give reason to track systematically the application of PFC-containing firefighting foams in order to identify contaminations of surface, ground and drinking waters.

Abstract  Perfluorooctanesulfonate (PFOS; C8F17SO3-), perfluorooctanesulfonamide (FOSA; C8F17SO2NH2), perfluorohexanesulfonate (PFHxS; C6F13SO3-), and perfluorooctanoate (PFOA; C7F15CO2-) were detected in 175 samples of liver and blood of bluefin tuna (Thunnus thynnus), swordfish (Xiphias gladius), common cormorants (Phalacrocorax carbo), bottlenose dolphins (Tursiops truncatus), striped dolphins (Stenella coeruleoalba), common dolphins (Delphinus delphi), fin whales (Balenoptera physalus), and long-finned pilot whales (Globicephala melas) from the Italian coast of the Mediterranean Sea and in livers of ringed seals (Phoca hispida), gray seals (Halichoerus grypus), white-tailed sea eagles (Haliaeetus albicilla), and Atlantic salmon (Salmo salar) from coastal areas of the Baltic Sea. PFOS was detected in all of the wildlife species analyzed. Concentrations of PFOS in blood decreased in order of bottlenose dolphins > bluefin tuna > swordfish. Mean PFOS concentrations (61 ng/ g, wet wt) in cormorant livers collected from Sardinia Island in the Mediterranean Sea were less than the concentrations of PFOA (95 ng/g, wetwt). PFOS concentrations in cormorant livers were significantly correlated with those of PFOA. FOSA was found in 14 of 19 livers or blood samples of marine mammals from the Mediterranean Sea. The highest concentration of 878 ng FOSA/g, wet wt, was found in the liver of a common dolphin. Livers of ringed and gray seals from the Bothnian Bay in the Baltic Sea contained PFOS concentrations ranging from 130 to 1,100 ng/g, wet wt. No relationships between PFOS concentrations and ages of ringed or gray seals were observed. Concentrations of PFOS in livers of seals were 5.5-fold greater than those in corresponding blood. A significant positive correlation existed between the PFOS concentrations in liver and blood, which indicates that blood can be used for nonlethal monitoring of PFOS. Trend analysis of PFOS concentrations in livers of white-tailed sea eagles collected from eastern Germany and Poland since 1979 indicated an increase in concentrations during the 1990s. Livers of Atlantic salmons did not contain quantifiable concentrations of any of the fluorochemicals monitored. PFOS is a widespread contaminant in wildlife from the Baltic and the Mediterranean Seas, while FOSA and PFOA were detected only in certain locations indicating their sporadic spatial distribution.

Abstract  To efficiently remove and recover perfluorinated compounds (PFCs) such as perfiuorooctanoic acid (PFOA) and perfluorooctanesulfonate (PFOS) from water, surface-tethered beta-cyclodextrins (CDs) on the surface of polystyrene (PS) particles (PS-beta-CDs) were prepared. The PS-beta-CDs with a 36% beta-CD content showed high adsorption capability against these PFCs from water via inclusion complex formation. The perfluorocarboxylic acids (PFCAs) adsorbed onto PS-beta-CDs were easily and quantitatively recovered by washing with acetone.