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1.
J Environ Manage ; 283: 111977, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33517051

RESUMO

Remediation of Poly- and perfluoroalkyl substances (PFASs) in the environment has rapidly increased due to growing concerns of environmental contamination and associated adverse toxicological effects on wildlife and humans due to bioaccumulation and extreme persistence. Although, PFASs are highly recalcitrant to conventional water treatment processes, there are some effective techniques available. Those techniques involve exceedingly high costs due to high energy use, and high capital or operational costs. Thus, most remediation techniques have limitations in field applications even though the laboratory scale experiments are promising. As a result of stringent new health and environmental regulatory standards are being established, development of suitable water treatment methodology is more challenging. Most of the separation and destruction techniques have their own limitations in field applications while the biological approaches to treat PFASs are extremely limited and are not currently considered as viable. In this review, extra consideration is given to novel advanced techniques for wide array of PFAS classes including short chain PFAS removal, and compare their efficiencies, effectiveness, energy use, sustainability, cost, and simplicity in laboratory scale to field applications. Electrochemical, sonochemical, advanced oxidation processers (AOPs) and plasma together with novel hybrid techniques are considered as effective approaches for PFASs removal and have shown promising results for long chain and some short chain PFASs, as well as extremely persistent per-fluoro alkyl acids (PFAAs). Therefore, it is essential to better understand the removal mechanisms to optimise the advanced treatment processes like hybrid techniques because, the unique physicochemical characteristics of various PFASs impose difficult challenges. Careful selection of a combined effective treatment methodology in an integrated processing unit, would be a revolutionary approach for complete elimination of PFASs from the environment. Considering the site-specific water quality parameters together with community perspectives will also make it more viable in real world field applications.


Assuntos
Água Potável , Fluorcarbonetos , Poluentes Químicos da Água , Purificação da Água , Fluorcarbonetos/análise , Humanos , Poluentes Químicos da Água/análise , Qualidade da Água
2.
Water Res ; 191: 116830, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33476798

RESUMO

Concentrations of 28 novel and legacy perfluoroalkyl and polyfluoroalkyl substances (PFASs) in wastewater from 77 industrial plants in the largest industrial complex in Korea were determined. The industrial plants were of eight types (advanced electronic, battery, chemical, general electronic, glass and ceramic, metal, polymer, and textile). PFAS concentrations in river water receiving the wastewater were determined to assess the impact of wastewater from the industrial complex. Only 19 and nine target PFASs were detected in untreated industrial wastewater and river water, respectively. Novel PFASs such as F53B (6:2 chlorinated polyfluoroalkyl ether sulfonate) were not detected. The mean PFASs concentration in industrial wastewater treatment plant effluent was 5.18 µg/L. The mean total PFASs concentration was highest in advanced electronic plant effluent, second highest in general electronic plant effluent, and lowest in battery and chemical plant effluents. Perfluorohexane sulfonate was the dominant homolog, being detected in effluent from plants of all classes and contributing 96% of total discharged PFASs by mass. Perfluorooctane sulfonate (included in the Stockholm Convention) use has decreased markedly since previous studies. Perfluorooctane sulfonate has largely been replaced by PFASs with fewer than seven carbon atoms. A similar change was found for river water receiving industrial wastewater.


Assuntos
Ácidos Alcanossulfônicos , Fluorcarbonetos , Poluentes Químicos da Água , Monitoramento Ambiental , Fluorcarbonetos/análise , República da Coreia , Rios , Águas Residuárias/análise , Água , Poluentes Químicos da Água/análise
3.
Environ Pollut ; 271: 116355, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33401211

RESUMO

Perfluoroalkyl acids (PFAAs) are a focus of scientific and regulatory attention nowadays. However, PFAAs dynamics in the environment and the factors that determine wildlife exposure are still not well understood. In this study we examined PFAAs exposure in chicks of a generalist seabird species, the lesser black-backed gull (Larus fuscus), breeding 49 km away of a PFAAs hotspot (a fluorochemical plant in Antwerp, Belgium). In order to study the pathways of PFAAs exposure, we measured how chicks' PFAAs burden varied with age, sex, and body condition. In addition, we related PFAA concentrations to chicks' diet using stable isotope signatures. For this purpose, we studied plasma PFAA concentrations in 1-week and 4-week-old gull chicks. Only 4 (PFOS, PFOA, PFDA and PFNA) out of the 13 target PFAA compounds were detected. Measured concentrations of PFOS and PFOA were generally high compared to other seabird species but were highly variable between individuals. Furthermore, our results suggest that maternal transfer plays a significant role in determining chicks' PFAAs burden, and that there are variable sources of exposure for PFOS and PFOA during post-hatching development. The association between PFOS and specific stable isotopes (i.e. δ15N and δ13C) suggests a higher exposure to PFOS in birds with a predominantly marine diet. We also found that males' condition was positively associated with PFOS plasmatic concentration, probably due to the indirect effect of being fed a high quality (marine) diet which appears PFOS rich. Yet, exact exposure source(s) for PFOA remain(s) unclear. Given that PFOS concentrations measured in some chicks surpassed the toxicity reference value calculated for top avian predators, continued monitoring of exposure and health of this gull population, and other wildlife populations inhabiting the area, is highly recommended.


Assuntos
Ácidos Alcanossulfônicos , Fluorcarbonetos , Ácidos Alcanossulfônicos/análise , Animais , Bélgica , Aves , Cruzamento , Caprilatos , Dieta , Monitoramento Ambiental , Fluorcarbonetos/análise , Humanos , Masculino
4.
J Chromatogr A ; 1638: 461899, 2021 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-33493975

RESUMO

Per- and polyfluoroalkyl substances (PFASs) have environmentally persistent, and the various types of PFASs have been detected in water environments. Many previous studies have performed data-dependent acquisition (DDA) of mass spectra from an environmental sample by high-resolution mass spectrometry to identify PFAS suspects individually. In comparison, the data-independent acquisition (DIA) of comprehensive mass spectra of the sample is a technology which enables to know the occurrences of suspects and non-targets simultaneously. However, it is difficult to associate the fragment ions of targeted precursor ions by retention time only, because of the existence of co-eluting ions derived from environmental samples. Since the separation of ions is not enough with only the conventional DIA method, here, we attempted to support it using ion mobility mass spectrometry (IMS) to distinguish the relevant ions from co-eluting ions by drift time. Firstly, suspect screening of PFASs with eternal database resulted in determining 32-96 PFAS suspects in firefighting foam impacted groundwater samples (n = 8) by suspect screening. Among all the pairs of respective precursor ions and fragment ions of the PFAS suspects, 5%-19% (4-9 PFASs) of them were associated without considering the drift time of IMS, while 37%-49% (15-43 PFASs) of them were associated with considering the drift time. The consideration of the drift time increased the association ratios in all samples. In a sample, most precursor ions could be associated with their fragment ions (41 of 43 PFASs) because at least one probable fragment ion was observed among three of maximum intensity fragment ions. Thus, the method improved the identification by excluding the unrelated co-eluting ions by IMS. Moreover, the method can acquire a certain reliable MS/MS spectra of suspects in environmental samples in one analysis. It is not essential to conduct instrumental analyses again for samples stored for a long time even when the data sets and/or methodologies of data analyses are modified (e.g., the original database, screening list, or statistical filtering/data cleaning approach). It will be particularly useful for studies that must analyze a large number of environmental samples.


Assuntos
Fluorcarbonetos/análise , Espectrometria de Mobilidade Iônica/métodos , Poluentes Químicos da Água/análise , Água Subterrânea/química , Processamento de Imagem Assistida por Computador , Espectrometria de Massas em Tandem
5.
Environ Sci Pollut Res Int ; 28(9): 11665-11671, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33410030

RESUMO

Drinking water is one of the major exposure routes to Perfluoroalkyl substances (PFASs). These chemicals are scarcely removed by the conventional process in water purification plants. In the present study, four models of pitcher-type water purifiers (A-D) were tested to evaluate their removal effect on six PFASs including PFOS and PFOA. All of the water purifiers removed PFASs, but the efficiency was dependent on the models. Model C was most effective; more than 90% of all PFASs were removed through the recommended life of the filter cartridge. Model D was least effective; its removal efficiency declined below 50% by the end of the cartridge's life. When compared by the carbon chain length of PFASs, the removal efficiency was "C12 > C10 > C8 > C6" in all models. This study clearly demonstrates that household water purifiers are effective in decreasing the exposure to PFASs through drinking water.


Assuntos
Ácidos Alcanossulfônicos , Água Potável , Fluorcarbonetos , Poluentes Químicos da Água , Purificação da Água , Fluorcarbonetos/análise , Poluentes Químicos da Água/análise
6.
Environ Pollut ; 270: 116219, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33401204

RESUMO

Seven perfluorinated and polyfluorinated substances (PFASs), namely perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDA), perfluorooctanoic acid (PFOA), perfluorooctane sulfonic acid (PFOS), perfluoroheptanoic acid (PFHpA), perfluorohexanoic acid (PFHxA), and perfluoro-1,10-decanedicarboxylic acid (PFDDA), were evaluated in urine and hair samples from children (age: 4-6 years, N = 53), airborne particles sampled at 17 kindergartens, and tap water and bottled water samples. All samples were collected in Hong Kong. The analytical results suggested widespread PFAS contamination. All target PFASs were detected in at least 32% of urine samples, with geometric mean (GM) concentrations ranging from 0.18 to 2.97 ng/L, and in 100% of drinking water samples at GM concentrations of 0.18-21.1 ng/L. Although PFOS and PFDDA were not detected in hair or air samples, the other target PFASs were detected in 48-70% of hair samples (GM concentrations: 2.40-233 pg/g) and 100% of air samples (GM concentrations: 14.8-536.7 pg/m3). In summary, the highest PFAS concentrations were detected in airborne particles measured in kindergartens. PFOA was the major PFAS detected in hair, urine, and drinking water samples, while PFOA, PFDA, and PFHpA were dominant in airborne particles. Although a significant difference in PFAS concentrations in hair samples was observed between boys and girls (p < .05), no significant sex-related difference in urinary PFAS or paired PFAS (hair/urine) concentrations was observed.


Assuntos
Ácidos Alcanossulfônicos , Água Potável , Fluorcarbonetos , Poluentes Químicos da Água , Ácidos Alcanossulfônicos/análise , Criança , Pré-Escolar , Feminino , Fluorcarbonetos/análise , Cabelo/química , Hong Kong , Humanos , Masculino , Poluentes Químicos da Água/análise
7.
Water Res ; 188: 116546, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33125991

RESUMO

The ubiquitous use and manufacturing of per- and polyfluoroalkyl substances (PFASs) have led to the contamination of water resources worldwide. High-pressure membranes, including nanofiltration (NF) and reverse osmosis (RO), are increasingly being deployed for water treatment and may be an effective barrier to PFASs. However, the impact of membrane operating conditions, background water matrix, and solute adsorption on rejection of diverse PFASs by NF and RO remains unclear. Rejection of perfluoroalkyl acids (PFAAs) present in aqueous film-forming foam (AFFF) diluted into a laboratory electrolyte matrix by NF and RO spiral wound elements was >98% and >99%, respectively. Rejection of the same PFAAs present in an AFFF-impacted groundwater matrix by NF was lower, between 92-98%, and was attributed to background water matrix constituents. Operating conditions did not have a significant impact on rejection of PFASs with the exception of shorter chain perfluoroalkyl sulfonic acids (PFSAs) in the AFFF-impacted groundwater matrix, where rejection increased with increasing flux. Structure-activity analysis of 42 PFASs, including 10 PFAAs and 32 PFASs identified in AFFF through high-resolution mass spectrometry suspect screening methods, showed some correlation between rejection and compound molecular weight. Adsorptive losses of PFAAs, most notably longer-chain hydrophobic PFAAs, to the spiral wound membrane elements and the membrane system were observed. Adsorption of PFAAs to the permeate spacer was especially pronounced and may have implications of artificially high rejection values. Still, rejection of PFASs by NF remained consistently >98% over 13 days of continuous operation.


Assuntos
Fluorcarbonetos , Poluentes Químicos da Água , Fluorcarbonetos/análise , Membranas/química , Filmes Cinematográficos , Pressão , Água , Poluentes Químicos da Água/análise
8.
Chemosphere ; 262: 128359, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33182107

RESUMO

Per- and polyfluoroalkyl substances (PFAS) have become ubiquitous environmental contaminants found in many parts of the globe and in all environmental compartments. The phase out of legacy C8 PFAS has led to an increase in functionality of the carbon backbone chain to include ether linkages and branching points. With the increased production of functionalized PFAS, there remains a paucity of information regarding the occurrence of constitutional isomers in the environment. In this study, a series of novel PFAS constitutional isomers were detected by high resolution mass spectrometry and characterized by MS/MS in river water collected weekly over 40 weeks. Constitutional isomers of C4H2F8O4S1 (-1.8 ± 2.5 ppm) were detected for the first time in 83% of the samples analyzed and the MS/MS fragmentation patterns clearly indicated there were two coeluting isomers present. Two chromatographically resolved peaks with deprotonated molecular formula C7H1F14O5S1 (1.9 ± 2.7 and 2.2 ± 3.1 ppm) were detected in 85% of the samples measured. MS/MS fragmentation patterns and a standard provided by a fluorochemical manufacturer confirmed the two isomers. A series of novel chlorinated PFAS were detected (M-1: C11H1Cl1F20O5 0.9 ± 2.7 ppm and C14H1Cl1F26O6 2.1 ± 2.6 ppm) in 34% of the water samples analyzed. The exact structure is not confirmed. River sediment collected below the water sample location contained several of the compounds detected in the water column illustrating the connectivity between the environmental compartments. Results highlight the need for further studies on the occurrence of isomers and authentic standards to confirm structures.


Assuntos
Fluorcarbonetos/análise , Fluorcarbonetos/química , Sedimentos Geológicos/análise , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Sedimentos Geológicos/química , Isomerismo , North Carolina , Rios/química , Espectrometria de Massas em Tandem/métodos , Poluentes Químicos da Água/química
9.
Sci Total Environ ; 754: 142146, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33254889

RESUMO

The biomagnification of per- and polyfluoroalkyl substances (PFASs) was investigated in a tropical mangrove food web from an estuary in Bahia, Brazil. Samples of 44 organisms (21 taxa), along with biofilm, leaves, sediment and suspended particulate matter were analyzed. Sum (∑) PFAS concentrations in biota samples were dominated by perfluorooctane sulfonate (PFOS, 93% detection frequency in tissues; 0.05 to 1.97 ng g-1 ww whole-body (wb)), followed by perfluorotridecanoate (PFTrDA, 57%; 0.01 to 0.28 ng g-1 ww wb). PFOS precursors such as perfluorooctane sulfonamide (FOSA, 54%; 0.01 to 0.32 ng g-1 ww wb) and N-ethyl perfluorooctane sulfonamide (EtFOSA; 30%; 0.01 to 0.21 ng g-1 ww wb) were also detected. PFAS accumulation profiles revealed different routes of exposure among bivalve, crustacean and fish groups. Statistics for left-censored data were used in order to minimize bias on trophic magnification factors (TMFs) calculations. TMFs >1 were observed for PFOS (linear + branched isomers), EtFOSA (linear + branched isomers), and perfluorononanoate (PFNA), and in all cases, dissimilar accumulation patterns were observed among different trophic positions. The apparent biodilution of some long-chain PFCAs through the food chain (TMF < 1) may be due to exposure from multiple PFAS sources. This is the first study investigating bioaccumulation of PFASs in a tropical food web and provides new insight on the behavior of this ubiquitous class of contaminants.


Assuntos
Ácidos Alcanossulfônicos , Fluorcarbonetos , Poluentes Químicos da Água , Ácidos Alcanossulfônicos/análise , Animais , Bioacumulação , Brasil , Monitoramento Ambiental , Fluorcarbonetos/análise , Cadeia Alimentar , Poluentes Químicos da Água/análise
10.
Sci Total Environ ; 754: 141900, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32916484

RESUMO

We compared long-term (1977 to 2014) trends in concentrations of PFAS in eggs of the marine sentinel species, the Northern gannet (Morus bassanus), from the Irish Sea (Ailsa Craig) and the North Sea (Bass Rock). Concentrations of eight perfluorinated carboxylic acids (PFCAs) and three perfluorinated sulfonates (PFSAs) were determined and we report the first dataset on PFAS in UK seabirds before and after the PFOS ban. There were no significant differences in ∑PFAS or ∑PFSAs between both colonies. The ∑PFSAs dominated the PFAS profile (>80%); PFOS accounted for the majority of the PFSAs (98-99%). In contrast, ∑PFCAs concentrations were slightly but significantly higher in eggs from Ailsa Craig than in those from Bass Rock. The most abundant PFCAs were perfluorotridecanoate (PFTriDA) and perfluoroundecanoate (PFUnA) which, together with PFOA, comprised around 90% of the ∑PFCAs. The ∑PFSAs and ∑PFCAs had very different temporal trends. ∑PFSAs concentrations in eggs from both colonies increased significantly in the earlier part of the study but later declined significantly, demonstrating the effectiveness of the phasing out of PFOS production in the 2000s. In contrast, ∑PFCAs concentrations in eggs were constant and low in the 1970s and 1980s, suggesting minimal environmental contamination, but residues subsequently increased significantly in both colonies until the end of the study. This increase appeared driven by rises in long chain compounds, namely the odd chain numbered PFTriDA and PFUnA. PFOA, had a very different temporal trend from the other dominant acids, with an earlier rise in concentrations followed by a decline in the last 15 years in Ailsa Craig; later temporal trends in Bass Rock eggs were unclear. Although eggs from both colonies contained relatively low concentrations of PFAS, the majority had PFOS residues that exceeded a suggested Predicted No Effect Concentration and ~ 10% of the eggs exceeded a suggested Lowest-Observable-Adverse-Effect.


Assuntos
Ácidos Alcanossulfônicos , Fluorcarbonetos , Morus , Ácidos Alcanossulfônicos/análise , Animais , Aves , Monitoramento Ambiental , Fluorcarbonetos/análise , Mar do Norte , Reino Unido
11.
Chemosphere ; 262: 128072, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33182132

RESUMO

A new synthesis method was developed to prepare an aluminum-based metal organic framework (MIL-96) with a larger particle size and different crystal habits. A low cost and water-soluble polymer, hydrolyzed polyacrylamide (HPAM), was added in varying quantities into the synthesis reaction to achieve >200% particle size enlargement with controlled crystal morphology. The modified adsorbent, MIL-96-RHPAM2, was systematically characterized by SEM, XRD, FTIR, BET and TGA-MS. Using activated carbon (AC) as a reference adsorbent, the effectiveness of MIL-96-RHPAM2 for perfluorooctanoic acid (PFOA) removal from water was examined. The study confirms stable morphology of hydrated MIL-96-RHPAM2 particles as well as a superior PFOA adsorption capacity (340 mg/g) despite its lower surface area, relative to standard MIL-96. MIL-96-RHPAM2 suffers from slow adsorption kinetics as the modification significantly blocks pore access. The strong adsorption of PFOA by MIL-96-RHPAM2 was associated with the formation of electrostatic bonds between the anionic carboxylate of PFOA and the amine functionality present in the HPAM backbone. Thus, the strongly held PFOA molecules in the pores of MIL-96-RHPAM2 were not easily desorbed even after eluted with a high ionic strength solvent (500 mM NaCl). Nevertheless, this simple HPAM addition strategy can still chart promising pathways to impart judicious control over adsorbent particle size and crystal shapes while the introduction of amine functionality onto the surface chemistry is simultaneously useful for enhanced PFOA removal from contaminated aqueous systems.


Assuntos
Alumínio/química , Caprilatos/análise , Fluorcarbonetos/análise , Dietilamida do Ácido Lisérgico/análogos & derivados , Estruturas Metalorgânicas/química , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Resinas Acrílicas/química , Adsorção , Carvão Vegetal/química , Dietilamida do Ácido Lisérgico/química , Tamanho da Partícula , Solubilidade , Propriedades de Superfície
12.
Ecotoxicol Environ Saf ; 207: 111250, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32920311

RESUMO

Perfluoroalkyl substances (PFAS), including perfluorooctanoic acid (PFOA), are industrial chemicals that are of concern due to their environmental presence, persistence, bioaccumulative potential, toxicity, and capacity for long-range transport. Despite a large body of research on environmental exposure, insufficient chronic aquatic toxicity data exist to develop water quality targets for clean-up of federal contaminated sites in Canada. Thus, our objective was to assess the aqueous toxicity of PFOA in chronic tests with Hyalella azteca (amphipod) and early-life stage tests with Pimephales promelas (fathead minnow). Toxicity data were analyzed based on measured PFOA concentrations. Amphipod exposures were 42 d (0.84-97 mg/L) and examined survival, growth, and reproduction. Fathead minnow exposures were 21 d (0.010-76 mg/L), which encompassed hatching (5 d) and larval stages until 16 d post-hatch; endpoints included hatching success, deformities at hatch, and larval survival and growth. Amphipod survival was significantly reduced at 97 mg/L (42-d LC50 = 51 mg/L), but growth and reproduction were more sensitive endpoints (42-d EC50 for both endpoints = 2.3 mg/L). Fathead minnows were less sensitive than amphipods, exhibiting no significant effects in all endpoints with the exception of uninflated swim bladder, which was significantly higher at 76 mg/L (15%) than controls (0%). Maximum concentrations of PFOA are generally in the ng/L range in global surface waters, but can reach the µg/L range in close proximity to major source inputs; therefore, environmental concentrations are well below those that caused toxicity in the current study. Our data will provide valuable information with which to assess the risk of PFOA at contaminated sites, and to set a target for site remediation.


Assuntos
Anfípodes , Caprilatos/análise , Fluorcarbonetos/análise , Poluentes Químicos da Água/análise , Animais , Canadá , Cyprinidae/crescimento & desenvolvimento , Larva/efeitos dos fármacos , Reprodução/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Qualidade da Água
13.
Environ Pollut ; 271: 116376, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33383424

RESUMO

Emerging per-/polyfluoroalkyl substances (PFASs), such as chlorinated polyfluorinated ether sulfonates (Cl-PFESAs), have been detected in human samples, yet investigation on their occurrence in pregnant women remains limited. Herein, ten legacy PFASs, branched perfluorooctanesulfonate (PFOS) and perfluorooctanoate (PFOA), two Cl-PFESAs, perfluoro-2-propoxypropanoic acid (HFPO-DA), and ammonium 4,8-dioxa-3H-perfluorononanoate (ADONA) were detected in serum samples from 480 pregnant women in Tianjin, China. The influencing effects of age, body mass index, gravidity, and parity were also evaluated. PFOS [geographic mean (GM): 7.05 ng/mL], 6:2Cl-PFESA (GM: 5.31 ng/mL), and PFOA (GM: 2.82 ng/mL) were the dominant PFASs in the serum of pregnant women, while neither HFPO-DA nor ADONA was detectable in any serum. The serum concentration of Cl-PFESAs and 6:2Cl-PFESA/PFOS ratio in the present study were 2-5 times higher than that in previous studies of pregnant women in China. Serum concentrations of Cl-PFESAs were significantly correlated with all detected PFAAs (Spearman's Rho: 0.15-0.69, p < 0.01) excepting perfluoropentanesulfonate (PFPeS), indicating common exposure sources for Cl-PFESAs and PFAAs and some particular exposure source for PFPeS. Younger age and multi-parity were associated with lower serum concentrations of PFOS and several perfluoroalkyl sulfonates but not associated with Cl-PFESAs or PFOA, suggesting an increasing exposure to Cl-PFESAs and PFOA which neutralized the impact of age and parity. Overall, this study indicated a relatively high exposure level and composition of 6:2Cl-PFESA in pregnant women in the north coast of China, which highlights the need to investigate the exposure sources in this area.


Assuntos
Ácidos Alcanossulfônicos , Fluorcarbonetos , Alcanossulfonatos , China , Éter , Éteres , Feminino , Fluorcarbonetos/análise , Humanos , Gravidez , Gestantes
14.
Sci Total Environ ; 761: 144107, 2021 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-33360549

RESUMO

Perfluorooctanoic acid (PFOA) is a synthetic, perfluorinated organic acid previously used in fluoropolymer production in the United States. PFOA has been a recent focal point for regulation because of its ubiquitous presence in drinking water throughout the United States. In 2016, the United States Environmental Protection Agency (US EPA) issued a lifetime drinking water Health Advisory (HA) for PFOA of 0.07 µg/L; several states have also implemented their own drinking water guidelines for PFOA. The current study aimed to evaluate the basis and derivation of state and federal guidelines for PFOA in drinking water, with particular emphasis on the exposure parameters utilized. Twelve distinct PFOA drinking water standards were identified ranging from 0.0051 to 2 µg/L. The US EPA HA assumptions were evaluated using a Monte Carlo analysis that included distributions for drinking water intake (DWI) rate and the relative source contribution (RSC). We determined that US EPA's HA of 0.07 µg/L is protective of 99% of the population of lactating women. We also demonstrated that the health-based guidelines were highly variable across states and that the actual RSC of PFOA from drinking water is likely greater than 20%, based on studies of actual PFOA exposures from dust, water, and food. A sensitivity analysis was performed using the same equations as the US EPA, while substituting the RSC and DWI variables; resulting in HAs ranging from 0.074 to 0.346 µg/L. We also evaluated the contribution of PFOA in drinking water to the systemic PFOA body burden of the general population using an available biokinetic model. We conclude that more rigorous efforts are warranted to establish consistent health-based drinking water guidelines for PFOA, given that drinking water is a primary source of human exposure to PFOA in the United States.


Assuntos
Água Potável , Fluorcarbonetos , Poluentes Químicos da Água , Caprilatos/análise , Água Potável/análise , Exposição Ambiental/análise , Feminino , Fluorcarbonetos/análise , Humanos , Lactação , Estados Unidos , Poluentes Químicos da Água/análise , Abastecimento de Água
15.
Chemosphere ; 262: 127900, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32799152

RESUMO

Sequencing batch reactors (SBRs) were operated for 36 days to simulate the potential wastewater treatment impacts as well as fate and transport of per- and polyfluoroalkyl substances (PFAS) that could be associated with a release of alcohol resistant aqueous film forming foam (AR-AFFF) from on-site methanol fire suppression systems. The results of this study indicate that two days of exposure to AFFF were associated with small reductions in mixed liquor solids content and nitrification rates. No impacts on denitrification or biological phosphorus removal were observed. The addition of AFFF was associated with increases in 6:2 fluorotelomer sulfonate (6:2 FTS) in influent, effluent, and solids samples in the SBR. The following biotransformation pathway is proposed: an unidentified fluorotelomer precursor quickly degraded to 6:2 FTS, which then slowly degraded to several identified degradation intermediates and terminal, short-chain perfluorocarboxylic acid products. Data for 6:2 FTS, which was used as a proxy for AFFF-associated PFAS, were extrapolated to estimate that a removal of approximately 70% of AFFF via effluent and solids wasting would occur after 4 days at a full-scale treatment plant. This information can be used to better understand potential impacts on downstream processes, including potable reuse and biosolids production.


Assuntos
Fluorcarbonetos/análise , Eliminação de Resíduos Líquidos , Águas Residuárias/química , Poluentes Químicos da Água/análise , Biotransformação , Fogo , Água
16.
Chemosphere ; 262: 127606, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32805650

RESUMO

PerFluoroOctane Sulfonate (PFOS), is a toxic anthropogenic chemical that has been produced and gradually released into the environment for the past seven decades. An accurate audit of global PFOS contamination and contaminated sites are yet to be published. The available technologies to remediate PFOS contaminated soil are limited and often basic strategies such as temporary soil containment are adopted as immediate measures to manage the contaminated sites. In this study, the in situ soil flushing technique is assessed for its capacity to remediate soil contaminated with PFOS. A complete treatment process with several operation units was proposed such as solvent flushing, ground water pumping, solvent recovery and water treatment for PFOS. Potential solvents were identified and it was observed that more than 98% PFOS removal could be attained by flushing with five bed volumes of 50% ethanol. In addition, the study investigated thirteen commercially available filter materials and identified PFA694E, K6362, MP 62, Amberlite IRA 67 and Dowexoptopore V493 as suitable to eliminate PFOS with competitive PFOS adsorption characteristics. The proposed method can be recommended to remediate PFOS in recognised contaminated soils, such as those at defence sites. Furthermore, a contaminated site with favourable characteristics to implement the suggested method was identified in Australia and described in this paper.


Assuntos
Ácidos Alcanossulfônicos/análise , Recuperação e Remediação Ambiental/métodos , Fluorcarbonetos/análise , Poluentes do Solo/análise , Adsorção , Austrália , Poluição Ambiental , Água Subterrânea , Solo , Purificação da Água
17.
Chemosphere ; 263: 128256, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33297201

RESUMO

Perfluorinated sulfonic acids (such as perfluorooctanesulfonic, PFOS, and short-chain analogues) are notorious halogenated pollutants that exhibit severe toxicity, even at minute levels. Limited number of experimental studies addressed their thermal decomposition at elevated temperatures. Such scenarios are particularly relevant to open fires and incineration of materials laden with perfluoroalkyl compounds (PFCs). Herein, we construct a detail kinetic model that illustrates major chemical reactions underpinning initial degradation of 1-butanesulfonic acid (CF3(CF2)3SO2OH), as a model compound of PFOS, and perfluorinated sulfonic acids in general. Reaction rate parameters were estimated based on an accurate density functional theory (DFT) formalism. The kinetic model incorporates four sets of reactions, namely, unimolecular decomposition channels, hydrofluorination, hydrolysis, and fragmentation of the alkyl chain. Results are discussed considering recent experimental measurements. Temperature-dependent profiles for a large array of perfluoroalkyl acyl fluorides, short perfluorinated cuts, and perfluorinated cyclic compounds, are presented. SO2 emerges as the main sulfur carrier, with a minor contribution from SO3. HF addition to double carbon bonds in alkenes, and to carbonyl bonds in aldehydic structures signifies a major sink pathway for hydrogen fluoride. Addition of moisture was shown to expedite the destruction of relatively large perfluoroalkyl acyl fluorides into C1 species. Construction of this model could aid in a better understanding of the fate and chemical transformation of PFCs under a pyrolytic environment pertinent to waste incineration and fluorine mineralization.


Assuntos
Ácidos Alcanossulfônicos , Poluentes Ambientais , Fluorcarbonetos , Poluentes Químicos da Água , Flúor , Fluorcarbonetos/análise , Cinética , Ácidos Sulfônicos
18.
Chemosphere ; 263: 128284, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33297228

RESUMO

Perfluoroalkyl acids (PFAAs) have emerged as global concerning contaminants because of their persistence, bioaccumulation, and toxicological effects. The transport and fate of PFAAs on dimension of plain river networks (PRNs) are difficult to model due to the unique regional characteristics (i.e., undirectional flows, low slope, complicated structure and connectivity) and the lack of data on PFAAs concentrations and compositions. A typical PRN (Taihu Basin, China) was selected to elucidate the spatial patterns of PFAAs in multi-matrices, including colloidal phase, soluble phase, suspended particles, and sediment. PFAAs were ubiquitously detected in plain rivers with total concentrations of 18.48-1220 ng/L in colloids, 139.07-721.37 ng/L in soluble phase, 97.69-2247 ng/g dw in suspended particles, and <72.04-178.12 ng/g dw in sediment. PFAAs were more likely to transport via dissolved phase and accumulate into sediment. Colloids carried 45.46-62.59% of ∑PFAAs in overlying water, while suspended particles contained <36.63% of ∑PFAAs, suggesting the important role of colloids in preloading PFAAs. Moreover, PFAAs variability was correlated with indicators of the structure and connectivity of river network by gray relational analysis. The mean gray relational degrees can be sorted as edge-node ratio (0.7609) > network connectivity (0.7191) > river density (0.7012) > water surface ratio (0.6887) > river development coefficient (0.6504) > functional connectivity (0.4780). These results suggested that the effects of catchment characteristics should be taken into account in understanding PFAAs fate in the PRNs.


Assuntos
Ácidos Alcanossulfônicos , Fluorcarbonetos , Poluentes Químicos da Água , Ácidos Alcanossulfônicos/análise , China , Monitoramento Ambiental , Fluorcarbonetos/análise , Rios , Poluentes Químicos da Água/análise
19.
Huan Jing Ke Xue ; 41(12): 5428-5437, 2020 Dec 08.
Artigo em Chinês | MEDLINE | ID: mdl-33374059

RESUMO

Coastal tourism resorts have been developing rapidly in recent years, and the quality of their waterbodies directly affects human health. Perfluoroalkyl substances (PFASs) are found in every environmental medium and have garnered widespread social concern because of their potential ecological harm. This study investigated the contamination characteristics and potential ecological risks of 12 PFASs in the water and sediment of 20 coastal tourism resorts in Shandong Peninsula. The results revealed that all targeted pollutants were observed in the water and most sediment samples collected from the coastal tourism resorts. The sum of the 12 PFASs ∑PFASs averaged 67.91 ng·L-1 and 5.89 ng·g-1 in the water and sediment, respectively. The predominant compounds were perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS) in both water and sediment. The ∑PFASs and its homologues concentration indicated the spatial variations in the water and sediment of different tourism resorts, and the values were higher in the tourism resorts near the city center and the industrial areas than in other areas. The partition coefficient (Kd) of all the target compounds in the water/sediment system of different tourism resorts showed obvious differences. In addition, the Kd of the compounds with longer carbon chains (C ≥ 7) generally had higher Kd values, which suggests that long-chain PFAAs are prone to adsorption by sediment. Therefore, the discharge of municipal industrial wastewater and domestic sewage is the main source of contamination. The salinity of water and the total carbon contents of sediment did not show any effect on the partition of PFASs in the water/sediment system. PFOS and PFOA might have great potential ecological risks in the water environment of all tourism resorts.


Assuntos
Ácidos Alcanossulfônicos , Fluorcarbonetos , Poluentes Químicos da Água , Ácidos Alcanossulfônicos/análise , Caprilatos , China , Cidades , Monitoramento Ambiental , Fluorcarbonetos/análise , Humanos , Turismo , Água , Poluentes Químicos da Água/análise
20.
Huan Jing Ke Xue ; 41(9): 4069-4075, 2020 Sep 08.
Artigo em Chinês | MEDLINE | ID: mdl-33124287

RESUMO

Perfluoroalkyl and polyfluoroalkyl substances (PFASs) are a group of manmade chemicals and are ubiquitously detected in aquatic environments. China is a major producer and consumer of PFASs. In this study, we investigated the occurrence and characteristics of PFASs in the surface sediments from three fluorine industrial parks in North China, the Xihe River in Liaoning Province (Fuxin Section), the Xiaoqing River in Shandong Province (Zibo Section), and the Yangtze River in Jiangsu Province (Changshu Section), using the UPLC/MS-MS method. The total concentration of PFASs (∑PFASs) in surface sediments of the Xihe River ranged from 15.8 to 2770 ng ·g-1, and PFTeDA and HFPO-DA were the dominant pollutants. In the surface sediments of the Xiaoqing River, ∑PFASs ranged from 12.2 to 7853 ng ·g-1, and PFOA and HFPO-DA were the dominant pollutants. In the surface sediments of the Yangtze river, ∑PFASs ranged from 9.20 to 35.9 ng ·g-1, and PFTeDA and 6:2 FTS were the main pollutants. Sewage discharge from the industrial parks (point source pollution) was the main source of PFASs in three regions in this study. The PFAS content and composition in three regions varied significantly depending on the production capacity and industry type. There was no significant correlation between the content of PFASs and its components and the particle size and TOC of the sediments. The correlations between the components of PFASs indicated that the enrichment process of PFASs in sediments was impacted by various factors.


Assuntos
Ácidos Alcanossulfônicos , Fluorcarbonetos , Poluentes Químicos da Água , Ácidos Alcanossulfônicos/análise , China , Monitoramento Ambiental , Flúor , Fluorcarbonetos/análise , Rios , Poluentes Químicos da Água/análise
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