POLST recall, concordance, and decision quality outcomes among nursing home residents and surrogate decision-makers.

BACKGROUND: POLST orders are actionable in an emergency, so it is important that the decisions be of high quality and concordant with current preferences. The goal of this study is to determine the relationship between concordance and decision quality outcomes, including decision satisfaction and decisional conflict, among nursing facility residents and surrogates who recall POLST. METHODS: We completed structured interviews in 29 nursing facilities with 275 participants who had previously signed a POLST form. This included residents who were still making their own medical decisions (n = 123) and surrogate decision-makers for residents without decisional capacity (n = 152). POLST recall was defined as remembering talking about and/or completing the POLST form previously signed by the participant. Concordance was determined by comparing preferences elicited during a standardized interview with the POLST form on file. Decisional conflict, decision satisfaction, and conversation quality were assessed with standardized tools. RESULTS: Half of participants (50%) remembered talking about or completing the POLST form, but recall was not associated with the length of time since POLST completion or concordance with existing preferences. In multivariable analyses, there was no association between POLST recall, concordance, and decision quality outcomes, though satisfaction was associated with conversation quality. CONCLUSIONS: Half of the residents and surrogates in this study recalled the POLST they previously signed. Neither the age of the form nor the ability to recall the POLST conversation should be considered indicators of whether existing POLST orders match current preferences. Findings confirm a relationship between POLST conversation quality and satisfaction, underscoring the importance of POLST completion as a communication process.

Reasons for Discordance Between Life-Sustaining Treatment Preferences and Medical Orders in Nursing Facilities Without POLST.

BACKGROUND: Life-sustaining treatment (LST) orders are important communication tools used to ensure preference-concordant care at the end of life. Recent studies reveal concerning rates of discordance between current preferences and documented LST orders, especially in nursing facilities without POLST. Reasons for discordance in facilities using POLST have been explored, however the majority of nursing facilities in the United States do not yet use the POLST form. DESIGN: Qualitative descriptive study using constant comparative analysis. SETTING: Nursing facilities in Indiana (n = 6) not using POLST. PARTICIPANTS: Residents (n = 15) and surrogate decision-makers of residents without decisional capacity (n = 15) with discordance between current preferences and documented LST orders. MEASUREMENTS: Do not resuscitate, do not hospitalize (DNH), and do not intubate (DNI) orders were extracted from medical charts. Current preferences were elicited using the Respecting Choices Advanced Steps model. A semi-structured interview guide was used to explore reasons for discordance between current preferences and LST orders. RESULTS: Reasons for discordance included: (1) inadequate information about the range of available LST options, what each involves, and how to formally communicate preferences; (2) no previous discussion with facility staff; (3) no documentation of previously expressed preferences; and (4) family involvement. CONCLUSION: Reasons for discordance between expressed preferences and LST orders suggest that in facilities without a uniform and systematic LST order documentation strategy like POLST, these conversations may not occur and/or be documented. Staff should be aware that residents and surrogates may have preferences about LSTs that require strategic solicitation and documentation.

Reasons for discordance and concordance between POLST orders and current treatment preferences.

BACKGROUND: The reasons for discordance between advance care planning (ACP) documentation and current preferences are not well understood. The POLST form offers a unique opportunity to learn about the reasons for discordance and concordance that has relevance for POLST as well as ACP generally. DESIGN: Qualitative descriptive including constant comparative analysis within and across cases. SETTING: Twenty-six nursing facilities in Indiana. PARTICIPANTS: Residents (n = 36) and surrogate decision-makers of residents without decisional capacity (n = 37). MEASUREMENTS: A semi-structured interview guide was used to explore the reasons for discordance or concordance between current preferences and existing POLST forms. FINDINGS: Reasons for discordance include: (1) problematic nursing facility practices related to POLST completion; (2) missing key information about POLST treatment decisions; (3) deferring to others; and (4) changes over time. Some participants were unable to explain the discordance due to a lack of insight or inability to remember details of the original POLST conversation. Explanations for concordance include: (1) no change in the resident's medical condition and/or the resident is unlikely to improve; (2) use of the substituted judgment standard for surrogate decision-making; and (3) fixed opinion about what is "right" with little to no insight. CONCLUSION: Participant explanations for discordance between existing POLST orders and current preferences highlight the importance of adequate structures and processes to support high quality ACP in nursing facilities. Residents with stable or poor health may be more appropriate candidates for POLST than residents with a less clear prognosis, though preferences should be revisited periodically as well as when there is a change in condition to help ensure existing documentation is concordant with current treatment preferences.

Factors associated with concordance between POLST orders and current treatment preferences.

BACKGROUND: POLST is widely used to document the treatment preferences of nursing facility residents as orders, but it is unknown how well previously completed POLST orders reflect current preferences (concordance) and what factors are associated with concordance. OBJECTIVES: To describe POLST preference concordance and identify factors associated with concordance. DESIGN: Chart reviews to document existing POLST orders and interviews to elicit current treatment preferences. SETTING: POLST-using nursing facilities (n = 29) in Indiana. PARTICIPANTS: Nursing facility residents (n = 123) and surrogates of residents without decisional capacity (n = 152). MEASUREMENTS: Concordance was determined by comparing existing POLST orders for resuscitation, medical interventions, and artificial nutrition with current treatment preferences. Comfort-focused POLSTs contained orders for do not resuscitate, comfort measures, and no artificial nutrition. RESULTS: Overall, 55.7% (123/221) of residents and 44.7% (152/340) of surrogates participated (total n = 275). POLST concordance was 44%, but concordance was higher for comfort-focused POLSTs (68%) than for non-comfort-focused POLSTs (27%) (p < 0.001). In the unadjusted analysis, increasing resident age (OR 1.04, 95% CI 1.01-1.07, p < 0.01), better cognitive functioning (OR 1.07, 95% CI 1.02-1.13, p < 0.01), surrogate as the decision-maker (OR 2.87, OR 1.73-4.75, p < 0.001), and comfort-focused POLSTs (OR 6.01, 95% CI 3.29-11.00, p < 0.01) were associated with concordance. In the adjusted multivariable model, only having an existing comfort-focused POLST was associated with higher odds of POLST concordance (OR 5.28, 95% CI 2.59-10.73, p < 0.01). CONCLUSIONS: Less than half of all POLST forms were concordant with current preferences, but POLST was over five times as likely to be concordant when orders reflected preferences for comfort-focused care. Findings suggest a clear need to improve the quality of POLST use in nursing facilities and focus its use among residents with stable, comfort-focused preferences.

Do Life-sustaining Treatment Orders Match Patient and Surrogate Preferences? The Role of POLST.

BACKGROUND: It is essential to high-quality medical care that life-sustaining treatment orders match the current, values-based preferences of patients or their surrogate decision-makers. It is unknown whether concordance between orders and current preferences is higher when a POLST form is used compared to standard documentation practices. OBJECTIVE: To assess concordance between existing orders and current preferences for nursing facility residents with and without POLST forms. DESIGN: Chart review and interviews. SETTING: Forty Indiana nursing facilities (29 where POLST is used and 11 where POLST is not in use). PARTICIPANTS: One hundred sixty-one residents able to provide consent and 197 surrogate decision-makers of incapacitated residents with and without POLST forms. MAIN MEASUREMENTS: Concordance was measured by comparing life-sustaining treatment orders in the medical record (e.g., orders about resuscitation, intubation, and hospitalization) with current preferences. Concordance was analyzed using population-averaged binary logistic regression. Inverse probability weighting techniques were used to account for non-response. We hypothesized that concordance would be higher in residents with POLST (n = 275) in comparison to residents without POLST (n = 83). KEY RESULTS: Concordance was higher for residents with POLST than without POLST (59.3% versus 34.9%). In a model adjusted for resident, surrogate, and facility characteristics, the odds were 3.05 times higher that residents with POLST had orders for life-sustaining treatment match current preferences in comparison to residents without POLST (OR 3.05 95% CI 1.67-5.58, p < 0.001). No other variables were significantly associated with concordance. CONCLUSIONS: Nursing facility residents with POLST are significantly more likely than residents without POLST to have concordance between orders in their medical records and current preferences for life-sustaining treatments, increasing the likelihood that their treatment preferences will be known and honored. However, findings indicate further systems change and clinical training are needed to improve POLST concordance.

Nursing facility residents' cardiopulmonary resuscitation decisions.

CONTEXT: As many as one-quarter of all residents in nursing facilities have cardiopulmonary resuscitation (CPR) as a documented choice in the medical record, despite the likelihood of limited medical benefit in this setting. OBJECTIVES: The aim of this study was to understand the perspectives of healthcare providers and nursing facility residents regarding CPR decisions. METHODS: We used qualitative interviews to examine the perspectives of residents with a documented decision for CPR in the medical record. We then compared residents' views with those of healthcare providers who routinely conduct advance care planning (ACP) conversations in the nursing facility setting. RESULTS: Five themes emerged from the interviews: (a) Resident versus Provider Concerns, (b) Offering Information versus Avoidance, (c) Lack of Understanding of CPR, (d) Lack of Awareness, and (e) 'Don't Keep Me on Machines'. Residents held misconceptions about CPR and/or exhibited an overall poor understanding of the relationship between their own health status and the likelihood of a successful CPR attempt. Although healthcare providers offer information and health education in an attempt to address knowledge gaps, these efforts are not always successful or even accepted by residents. Resident viewpoints and priorities differed from healthcare providers in ways that affected communication about CPR. CONCLUSIONS: Unrecognised differences in perceptions between providers and residents affect key aspects of ACP communication that can impact CPR decision-making. The concerns and priorities of institutionalized older adults may differ from those of healthcare providers, creating challenges for engaging some residents in ACP. IMPLICATIONS FOR PRACTICE: ACP communication models and training should be designed not only to explore nursing facility residents' goals, values, and preferences, but also to elicit any underlying differences in perceptions that may affect communication. Healthcare providers can identifying the primary concerns of residents and assist them with integrating or reframing these issues as a part of ACP discussions.

C12-30 α-Bromo-Chloro "Alkenes": Characterization of a Poorly Identified Flame Retardant and Potential Environmental Implications.

Bromo-chloro alkenes (Br-Cl PXAs) have been used for over 30 years as flame retardants and are listed on several national chemical inventories. Very little publicly available information is available on Br-Cl PXAs, and thus preliminary ecological risk screening is challenging due to the lack of basic information such as molecular structure and associated physicochemical properties. Due to their likely similarity with chlorinated paraffins (CPs), Br-Cl PXAs may pose a similar environmental hazard. Several structural databases list such substances as "alkenes", although the industrial synthesis involves halogenation of linear alpha-olefins and would be expected to produce linear alkanes. In this study, a combination of high-resolution separation and mass spectrometric techniques were used to characterize a Br-Cl PXA industrial technical product, C12-30 bromo-chloro alpha-alkenes (CAS RN 68527-01-5). The results show this product is dominated by C18 carbon chain lengths, substituted with 3-7 chlorine atoms and 1-3 bromine atoms on an alkane chain. Long-chain C18 chlorinated paraffins are also present, although they represent a relatively minor component. Experimental log KOW (6.9 to 8.6) and estimated log KOA (10.5 to 13.5) and log KAW (-5.1 to -0.6) partition coefficients suggest that this chemical will behave similarly to medium- and long-chain CPs as well as other persistent organic pollutants, such as highly chlorinated pesticides and polychlorinated biphenyls. The results of this study provide an initial step toward understanding the environmental behavior and persistence of Br-Cl PXAs, highlighting the need for further assessment and re-evaluation of the current structure(s) assigned to these compounds.

A Tool to Assess Patient and Surrogate Knowledge About the POLST (Physician Orders for Life-Sustaining Treatment) Program.

CONTEXT: It is especially important that patients are well informed when making high-stakes, preference-sensitive decisions like those on the Physician Orders for Life-Sustaining Treatment (POLST) form. However, there is currently no way to easily evaluate whether patients understand key concepts when making these important decisions. OBJECTIVES: To develop a POLST knowledge survey. METHODS: Expert (n = 62) ratings of key POLST facts were used to select items for a POLST knowledge survey. The survey was administered to nursing facility residents (n = 97) and surrogate decision-makers (n = 112). A subset (n = 135) were re-administered the survey after a standardized advance care planning discussion to assess the scale's responsiveness to change. RESULTS: The 19-item survey demonstrated adequate reliability (α = 0.72.). Residents' scores (x = 11.4, standard deviation 3.3) were significantly lower than surrogate scores (x = 14.7, standard deviation 2.5) (P < 0.001). Scores for both groups increased significantly after administration of a standardized advance care planning discussion (P < 0.001). Although being a surrogate, age, race, education, cognitive functioning, and health literacy were significantly associated with higher POLST Knowledge Survey scores in univariate analyses, only being a surrogate (P < 0.001) and being white (P = 0.028) remained significantly associated with higher scores in multivariate analyses. CONCLUSION: The 19-item POLST Knowledge Survey demonstrated adequate reliability and responsiveness to change. Findings suggest the survey could be used to identify knowledge deficits and provide targeted education to ensure adequate understanding of key clinical decisions when completing POLST.

Use of the Physician Orders for Scope of Treatment Program in Indiana Nursing Homes.

OBJECTIVES: To assess the use of the Indiana Physician Orders for Scope of Treatment (POST) form to record nursing home (NH) resident treatment preferences and associated practices. DESIGN: Survey. SETTING: Indiana NHs. PARTICIPANTS: Staff responsible for advance care planning in 535 NHs. MEASUREMENTS: Survey about use of the Indiana POST, related policies, and educational activities. METHODS: NHs were contacted by telephone or email. Nonresponders were sent a brief postcard survey. RESULTS: Ninety-one percent (n=486) of Indiana NHs participated, and 79% had experience with POST. Of the 65% of NHs that complete POST with residents, 46% reported that half or more residents had a POST form. POST was most often completed at the time of admission (68%). Only 52% of participants were aware of an existing facility policy regarding use of POST; 80% reported general staff education on POST. In the 172 NHs not using POST, reasons for not using it included unfamiliarity with the tool (23%) and lack of facility policies (21%). CONCLUSION: Almost 3 years after a grassroots campaign to introduce the voluntary Indiana POST program, a majority of NHs were using POST to support resident care. Areas for improvement include creating policies on POST for all NHs, training staff on POST conversations, and considering processes that may enhance the POST conversation, such as finding an optimal time to engage in conversations about treatment preferences other than a potentially rushed admission process.

Application of a comprehensive extraction technique for the determination of poly- and perfluoroalkyl substances (PFASs) in Great Lakes Region sediments.

A comprehensive method to extract perfluoroalkane sulfonic acids (PFSAs), perfluoroalkyl carboxylic acids (PFCAs), polyfluoroalkyl phosphoric acid diesters (diPAPs), perfluoroalkyl phosphinic acids (PFPiAs) and perfluoroalkyl phosphonic acids (PFPAs) from sediment and analysis by liquid chromatography tandem mass spectrometry (LC-MS/MS) was developed and applied to sediment cores from three small isolated lakes (Plastic Lake, Lake 442, Lake Tettegouche) and Lake Ontario in the Great Lakes Region. Recoveries of the target compounds using the optimized acetonitrile/sodium hydroxide extraction ranged from 73% to 120%. The greatest concentrations of per- and polyfluorinated alkyl substances (PFASs) were recorded in sediment from Lake Ontario (ΣPFASs 13.1 ng/g), where perfluorooctane sulfonic acid (PFOS) contributed over 80% of the total. Concentrations in Lake Ontario were approximately 1-2 orders of magnitude greater than the more remote lakes subject to primarily atmospheric inputs. Whilst the PFAS contribution in Lake Ontario was dominated by PFOS, the more remote lakes contained sediment with higher proportions of PFCAs. Trace amounts of emerging PFASs (diPAPs and PFPiAs) were found in very recent surface Lake Ontario and remote lake sediments.

Quantitative Analysis of Mixed Halogen Dioxins and Furans in Fire Debris Utilizing Atmospheric Pressure Ionization Gas Chromatography-Triple Quadrupole Mass Spectrometry.

Residential and commercial fires generate a complex mixture of volatile, semivolatile, and nonvolatile compounds. This study focused on the semi/nonvolatile components of fire debris to better understand firefighter exposure risks. Using the enhanced sensitivity of gas chromatography coupled to atmospheric pressure ionization-tandem mass spectrometry (APGC-MS/MS), complex fire debris samples collected from simulation fires were analyzed for the presence of potentially toxic polyhalogenated dibenzo-p-dioxins and dibenzofurans (PXDD/Fs and PBDD/Fs). Extensive method development was performed to create multiple reaction monitoring (MRM) methods for a wide range of PXDD/Fs from dihalogenated through hexa-halogenated homologue groups. Higher halogenated compounds were not observed due to difficulty eluting them off the long column used for analysis. This methodology was able to identify both polyhalogenated (mixed bromo-/chloro- and polybromo-) dibenzo-p-dioxins and dibenzofurans in the simulated burn study samples collected, with the dibenzofuran species being the dominant compounds in the samples. Levels of these compounds were quantified as total homologue groups due to the limitations of commercial congener availability. Concentration ranges in household simulation debris were observed at 0.01-5.32 ppb (PXDFs) and 0.18-82.11 ppb (PBDFs). Concentration ranges in electronics simulation debris were observed at 0.10-175.26 ppb (PXDFs) and 0.33-9254.41 ppb (PBDFs). Samples taken from the particulate matter coating the firefighters' helmets contained some of the highest levels of dibenzofurans, ranging from 4.10 ppb to 2.35 ppm. The data suggest that firefighters and first responders at fire scenes are exposed to a complex mixture of potentially hundreds to thousands of different polyhalogenated dibenzo-p-dioxins and dibenzofurans that could negatively impact their health.

Comprehensive characterization of the halogenated dibenzo-p-dioxin and dibenzofuran contents of residential fire debris using comprehensive two-dimensional gas chromatography coupled to time of flight mass spectrometry.

A comprehensive approach was taken to characterize the polyhalogenated dibenzo-p-dioxin and dibenzofuran contents of fire debris. Household and electronics fire simulations were performed to create samples representative of those firefighters most typically come in contact with. Sample analysis was performed using GC×GC-TOFMS to provide a comprehensive profile of the halogenated dioxins and furans present among the two types of fire debris. Both the household fire and electronics fire simulations produced a significant amount of polybrominated dibenzofurans. Only the electronics rich fire simulation produced mixed halogenated (Br/Cl) dibenzofurans in amounts above the limit of detection of the analytical method. Of the mixed halogenated dibenzofurans identified, a majority were those having no commercially available standard to allow for specific congener identification. GC×GC-TOFMS was extremely beneficial for the identification of compound classes due to the manner in which compounds classify in the two-dimensional chromatographic plane, thus aiding data reduction for these materials.

Complementary nontargeted and targeted mass spectrometry techniques to determine bioaccumulation of halogenated contaminants in freshwater species.

Assessing the toxicological significance of complex environmental mixtures is challenging due to the large number of unidentified contaminants. Nontargeted analytical techniques may serve to identify bioaccumulative contaminants within complex contaminant mixtures without the use of analytical standards. This study exposed three freshwater organisms (Lumbriculus variegatus, Hexagenia spp., and Pimephales promelas) to a highly contaminated soil collected from a recycling plant fire site. Biota extracts were analyzed by Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS) and mass defect filtering to identify bioaccumulative halogenated contaminants. Specific bioaccumulative isomers were identified by comprehensive two-dimensional gas chromatography high-resolution time-of-flight mass spectrometry (GCxGC-HRToF). Targeted analysis of mixed brominated/chlorinated dibenzo-p-dioxins and dibenzofurans (PXDD/PXDFs, X = Br and Cl) was performed by atmospheric pressure gas chromatography tandem mass spectrometry (APGC-MS/MS). Relative sediment and biota instrument responses were used to estimate biota-sediment accumulation factors (BSAFs). Bioaccumulating contaminants varied among species and included polychlorinated naphthalenes (PCNs), polychlorinated dibenzofurans (PCDFs), chlorinated and mixed brominated/chlorinated anthracenes/phenanthrenes, and pyrenes/fluoranthenes (Cl-PAHs and X-PAHs, X = Br and Cl), as well as PXDD/PXDFs. Bioaccumulation potential among isomers also varied. This study demonstrates how complementary high-resolution mass spectrometry techniques identify persistent and bioaccumulative contaminants (and specific isomers) of environmental concern.

Using mass defect plots as a discovery tool to identify novel fluoropolymer thermal decomposition products.

Fire events involving halogenated materials, such as plastics and electronics, produce complex mixtures that include unidentified toxic and environmentally persistent contaminants. Ultrahigh-resolution mass spectrometry and mass defect filtering can facilitate compound identification within these complex mixtures. In this study, thermal decomposition products of polychlorotrifluoroethylene (PCTFE, [-CClF-CF2 -]n), a common commercial polymer, were analyzed by Fourier transform ion cyclotron resonance mass spectrometry. Using the mass defect plot as a guide, novel PCTFE thermal decomposition products were identified, including 29 perhalogenated carboxylic acid (PXCA, X = Cl,F) congener classes and 21 chlorine/fluorine substituted polycyclic aromatic hydrocarbon (X-PAH, X = Cl,F) congener classes. This study showcases the complexity of fluoropolymer thermal decomposition and the potential of mass defect filtering to characterize complex environmental samples.

Perfluoroalkyl acids in the Canadian environment: multi-media assessment of current status and trends.

In Canada, perfluoroalkyl acids (PFAAs) have been the focus of several monitoring programs and research and surveillance studies. Here, we integrate recent data and perform a multi-media assessment to examine the current status and ongoing trends of PFAAs in Canada. Concentrations of perfluorooctane sulfonate (PFOS), perfluorooctanoate (PFOA), and other long-chain perfluorocarboxylates (PFCAs) in air, water, sediment, fish, and birds across Canada are generally related to urbanization, with elevated concentrations observed around cities, especially in southern Ontario. PFOS levels in water, fish tissue, and bird eggs were below their respective Draft Federal Environmental Quality Guidelines, suggesting there is low potential for adverse effects to the environment/organisms examined. However, PFOS in fish and bird eggs tended to exceed guidelines for the protection of mammalian and avian consumers, suggesting a potential risk to their wildlife predators, although wildlife population health assessments are needed to determine whether negative impacts are actually occurring. Long-term temporal trends of PFOS in suspended sediment, sediment cores, Lake Trout (Salvelinus namaycush), and Herring Gull (Larus argentatus) eggs collected from Lake Ontario increased consistently from the start of data collection until the 1990s. However, after this time, the trends varied by media, with concentrations stabilizing in Lake Trout and Herring Gull eggs, and decreasing and increasing in suspended sediment and the sediment cores, respectively. For PFCAs, concentrations in suspended sediment, sediment cores, and Herring Gulls generally increased from the start of data collection until present and concentrations in Lake Trout increased until the late 1990s and subsequently stabilized. A multimedia comparison of PFAA profiles provided evidence that unexpected patterns in biota of some of the lakes were due to unique source patterns rather than internal lake processes. High concentrations of PFAAs in the leachate and air of landfill sites, in the wastewater influent/effluent, biosolids, and air at wastewater treatment plants, and in indoor air and dust highlight the waste sector and current-use products (used primarily indoors) as ongoing sources of PFAAs to the Canadian environment. The results of this study demonstrate the utility of integrating data from different media. Simultaneous evaluation of spatial and temporal trends in multiple media allows inferences that would be impossible with data on only one medium. As such, more co-ordination among monitoring sites for different media is suggested for future sampling, especially at the northern sites. We emphasize the importance of continued monitoring of multiple-media for determining future responses of environmental PFAA concentrations to voluntary and regulatory actions.

Heterogeneous photooxidation of fluorotelomer alcohols: a new source of aerosol-phase perfluorinated carboxylic acids.

Little is known of the atmospheric fate(s) of fluorotelomer alcohols (FTOHs), a class of high-production-volume chemicals used in the production of water- and oil-repelling surface coatings and which have been detected in a wide variety of urban and remote environmental matrices. In the present study, we investigated the uptake and photochemistry of FTOHs at the surface of TiO2, Fe2O3, Mauritanian sand, and Icelandic volcanic ash. Gas-phase 3,3,3-trifluoropropanol, 4:2 FTOH, and 6:2 FTOH exhibited significant uptake to each of the surfaces under study. The sand- and ash-catalyzed heterogeneous photooxidation of 6:2 FTOH resulted in the rapid production and subsequent slow degradation of surface-sorbed perfluorinated carboxylic acids (PFCAs). We suggest that this transformation, which proceeds via saturated and unsaturated fluorotelomer carboxylic acid intermediates (6:2 FTCA/FTUCA), is catalyzed by Fe and Ti contained within the samples. These results provide the first evidence that the heterogeneous oxidation of FTOHs at metal-rich atmospheric surfaces may provide a significant loss mechanism for these chemicals and also act as a source of aerosol-phase PFCAs close to source regions. Subsequent long-range transport of these aerosol-sorbed PFCAs has the potential to join oceanic transport and local gas-phase FTOH oxidation as a source of PFCAs to Arctic regions.

Analysis of mixed halogenated dibenzo-p-dioxins and dibenzofurans (PXDD/PXDFs) in soil by gas chromatography tandem mass spectrometry (GC-MS/MS).

Mixed halogenated dibenzo-p-dioxins and dibenzofurans (PXDD/PXDFs, X=Br, Cl) are formed through combustion processes, and may be more toxic than their corresponding chlorinated and brominated analogues. With 4600 potential congeners, limited analytical standards, and complex environmental matrices, PXDD/PXDFs present a significant analytical challenge. Gas chromatography tandem mass spectrometry (GC-MS/MS) offers both selectivity and sensitivity through multiple reaction monitoring of unique transitions in a novel approach to PXDD/PXDF congener identification. Method validation was performed through analysis of soil samples obtained from a recycling plant fire. Of the PXDD/PXDFs examined, monobromo-dichlorodibenzofuran was the most prevalent, ranging in concentration from 8.6ngg(-1) to 180ngg(-1). Dibromo-dichlorodibenzo-p-dioxin, a compound of toxicological concern, ranged from 0.41ngg(-1) to 10ngg(-1). Concentrations of PXDD/PXDFs were between 6% and 10% that of the corresponding polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/PCDFs), with the exception of dibromo-dichlorodibenzo-p-dioxin concentrations, which were 36% that of tetrachlorodibenzo-p-dioxins. Higher levels of polybrominated PXDD/PXDFs may indicate a significant bromine source was present during combustion.

Fate, distribution, and contrasting temporal trends of perfluoroalkyl substances (PFASs) in Lake Ontario, Canada.

Lake Ontario water and sediment collected from tributary, nearshore, and open lake sites were analyzed for perfluoroalkyl substances (PFASs), namely perfluoroalkyl carboxylic acids (PFCAs, F(CF(2))(n)CO(2)(-); n=6-11,13) and perfluoroalkane sulfonic acids (PFSAs, F(CF(2))(n)SO(3)(-); n=6,8,10). Survey results of surface sediment and water indicated that shorter chained PFASs were predominant in and near urban/industrial area watersheds, while longer chained PFASs were predominant in fine-grained sediment from major depositional basins. Niagara River suspended solids (1981-2006) demonstrated temporal trends that may have been influenced by recent changes in North American production and use of PFASs. Perfluorooctane sulfonate (PFOS) reached a peak concentration in 2001 of 1.1 ng/g, followed by a decrease from 2001 to 2006 (half-life=9 years). Perfluorooctanoic acid (PFOA) increased from 2001 to 2006 (doubling time= 2 years) reaching a peak concentration of 0.80 ng/g. In contrast, three sediment cores from western, central, and eastern Lake Ontario showed increasing temporal trends to surface sediment for all PFASs. PFOA and PFOS concentrations increased from 1988 to 2004 (doubling time= ~ 4 years) in the western Lake Ontario core. The observed variations in temporal trends from different environmental compartments may be a result of the physico-chemical properties of PFASs, ongoing emissions, and the environmental transformation and degradation of PFAS precursor compounds.

Toxicity of fluorotelomer carboxylic acids to the algae Pseudokirchneriella subcapitata and Chlorella vulgaris, and the amphipod Hyalella azteca.

Perfluorinated acids (PFAs) have elicited significant global regulatory and scientific concern due to their persistence and global pervasiveness. A source of PFAs in the environment is through degradation of fluorotelomer carboxylic acids (FTCAs) but little is known about the toxicity of these degradation products. Previous work found that FTCAs were two to three orders of magnitude more toxic to some freshwater invertebrates than their PFA counterparts and exhibited comparable chain-length-toxicity relationships. In this study, we investigated the toxicity of the 6:2, 8:2, and 10:2 saturated (FTsCA) and unsaturated (FTuCA) fluorotelomer carboxylic acids to two species of freshwater algae, Chlorella vulgaris and Pseudokirchneriella subcapitata, and the amphipod, Hyalella azteca. C. vulgaris was generally the most sensitive species, with EC50s of 26.2, 31.8, 11.1, and 4.2 mg/L for the 6:2 FTsCA, 6:2 FTuCA, 8:2 FTuCA, and 10:2 FTsCA, respectively. H. azteca was most sensitive to the 8:2 FTsCA and 10:2 FTuCA, with LC50s of 5.1 and 3.7 mg/L. The toxicity of the FTCAs generally increased with increasing carbon chain length, and with saturation for most of the species tested, with the exception of P. subcapitata, which did not exhibit any trend. These observations agree with chain-length-toxicity relationships previously reported for the PFCAs and support the greater toxicity of the FTCAs compared to PFCAs. However, the toxicity values are approximately 1000-fold above those detected in the environment indicating negligible risk to aquatic invertebrates.

Fate of fluorotelomer acids in a soil-water microcosm.

Fluorotelomer carboxylic acids (FTCAs) and the corresponding unsaturated acids (FTUCAs) are known intermediates in the biodegradation of industrially produced fluorotelomer alcohols (FTOHs) to environmentally persistent perfluorinated carboxylic acids (PFCAs). The FTCAs and FTUCAs are of concern for their toxicity, reactivity, and unknown disposition in the environment. The fate of these compounds was investigated in a simple sediment-water microcosm system. Microcosms were spiked with 8:2 FTCA, 10:2 FTCA, 8:2 FTUCA, or 10:2 FTUCA, after which sediment and water samples were collected over time and analyzed by liquid chromatography-tandem mass spectrometry (LC/MS/MS). The FTCAs and FTUCAs investigated in the present study were observed to degrade rapidly, and sorption of these analytes to sediment was found to be greater for the 10:2 telomer acids compared with the corresponding 8:2 telomer acids. Identifiable degradation products of FTCAs and FTUCAs were observed; however, an overall molar balance could not be achieved. The observed reactivity and lability of these analytes may contribute to the low levels of FTCAs detected in environmental samples.