Abstract  Anemia of diverse etiology is a common complication of chronic liver diseases. The causes of anemia include acute or chronic gastrointestinal hemorrhage, and hypersplenism secondary to portal hypertension. Severe hepatocellular disease predisposes to hemorrhage because of impaired blood coagulation caused by deficiency of blood coagulation factors synthesized by hepatocytes, and/or thrombocytopenia. Aplastic anemia, which is characterized by pancytopenia and hypocellular bone marrow, may follow the development of hepatitis. Its presentation includes progressive anemia and hemorrhagic manifestations. Hematological complications of combination therapy for chronic viral hepatitis include clinically significant anemia, secondary to treatment with ribavirin and/or interferon. Ribavirin-induced hemolysis can be reversed by reducing the dose of the drug or discontinuing it altogether. Interferons may contribute to anemia by inducing bone marrow suppression. Alcohol ingestion is implicated in the pathogenesis of chronic liver disease and may contribute to associated anemia. In patients with chronic liver disease, anemia may be exacerbated by deficiency of folic acid and/or vitamin B12 that can occur secondary to inadequate dietary intake or malabsorption.

Abstract  Perfluoroalkyl and polyfluoroalkyl substances (PFASs) draw considerable attention for their potential toxic effects in humans and environment. Drinking water is accepted as one of the major exposure pathways for PFASs. In this study, we measured concentrations of 10 perfluoroalkyl substances in 94 tap water samples collected in two different sampling periods (August 2017 and February 2018) from 33 provinces of Turkey, as well as in 26 different brands of plastic and glass-bottled water samples sold in supermarkets in Turkey. Perfluorohexanoic acid (PFHxA), perfluorobutane sulfonate (PFBS) and perfluoropentanoic acid (PFPeA) were the most frequently detected PFASs in the samples of tap waters. The maximum concentrations in tap waters were measured as 2.90, 2.37, 2.18, 2.04, and 1.93 ng/L, for PFHxA, perfluorooctanoic acid (PFOA), perfluorohexane sulfonate (PFHxS), perfluorooctane sulfonate (PFOS), and perfluorobutanoic acid (PFBA), respectively. The most abundant perfluorinated chemical in tap water samples was PFBA with 17%, followed by PFOS (13%), PFBS (12%), perfluoroheptanoic acid (PFHpA) (11%), PFHxA (11%), and PFOA (11%). The total PFASs concentration in tap water ranged from 0.08 to 11.27 ng/L. As regards bottled waters, the concentrations of PFASs were generally lower than those in tap water samples. These results revealed that tap water samples in Turkey might be considered generally safe based on the established guidelines around the world. However, due to their persistence and potential to accumulate and reach higher concentrations in the environment, careful monitoring of PFASs in all types of water is critical.

Abstract  Chicken, duck, egg, and duck egg samples from the Yangtze River Delta and Pearl River Delta regions in China were analyzed for 17 perfluorinated compounds (PFCs). The concentrations of PFCs in chicken and duck livers ranged from

Abstract  Per- and polyfluoroalkyl substances (PFAS) are found ubiquitously in wastewater treatment plants (WWTPs) due to their multiple sources in industry and consumer products. In Australia, limited spatial data are available on PFAS levels in WWTPs influent, while no temporal data have been reported. The aim of this study was to investigate the occurrence and temporal trend of PFAS in the influent of two large WWTPs in Australia (WWTP A and B) over a four-year period. Daily influent samples were collected over one week at different seasons from 2014 to 2017. Eleven perfluoroalkyl acids (PFAA) (i.e. seven perfluoroalkyl carboxylic acids (PFCAs) and four perfluoroalkyl sulfonic acids (PFSA)) were detected with mean S11PFAA concentrations of 57?±?3.3–94?±?17?ng/L at WWTP A, and 31?±?6.1–142?±?73?ng/L at WWTP B. The highest mean concentrations were observed for perfluorohexanoate (PFHxA) (20?±?2?ng/L) in WWTP A, and perfluorooctane sulfonate (PFOS) (17?±?13?ng/L) in WWTP B. The precursor 6:2 fluorotelomer sulfonate was detected over five sampling periods from Aug 2016 to Oct 2017, with mean concentrations of 37?±?18–138?±?51?ng/L for WWTP A and 8.8?±?4.5–29?±?5.1?ng/L for WWTP B. Higher concentration of 6:2 FTS (1.8–11 folds) than those of PFOA and PFOS in WWTP A indicate a likely substitution of C8 PFAA by fluorotelomer-based PFAS in this catchment. Temporal trends (annual and seasonal) in per-capita mass load were observed for some PFAA, increasing for PFPeA, PFHxA, PFHpA, PFNA, and PFHxS, while decreasing for PFBS and PFOS in either WWTPs. Notably, elevated levels of PFOS in October 2017 were observed at both WWTPs with the highest per capita mass load of up to 67?µg/day/inhabitant. For some PFAS release trends, longer sampling periods would be required to achieve acceptable statistical power.

Abstract  In this study, the electrocoagulation of perfluorooctanoic acid (PFOA) in water using an iron (Fe) electrode was investigated. The effects of the current density, stirring speed, and electrolyte concentration (NaCl) on the corresponding removal rates of PFOA were examined. An increase in the current density from 2.4 to 80.0 mA cm−2 led to a significant increase in the removal efficiency of PFOA from 10.0 to 100.0% within 6 h. Formate (HCOO−) ions and three shorter-chain perfluorocarboxylates (i.e., perfluoropentanoic acid; PFPeA, perfluorohexanoic acid; PFHxA, and perfluoroheptanoic acid; PFHpA) were observed as organic byproducts during the electrocoagulation of PFOA, indicating that the C-C bond between C7F15 was first broken down and then was degraded into short carbon-chain compounds by PFOA decomposition. 65% of fluorine recovery as fluoride ions and organic fluorine in shorter-chain byproducts (PFPeA, PFHxA, and PFHpA) with 60% of total organic carbon (TOC) removal was achieved within 6 h during electrocoagulation, while the complete removal of PFOA was achieved. Our results imply that electrocoagulation using Fe electrode can effectively degrade PFOA into shorter-chain byproducts with significant mineralization. © 2020 Elsevier B.V.

Abstract  Recently, perfluorohexanoic acid (PFHxA), an emerging contaminant, has been detected at a high level in the water environment. Its possible presence in drinking water treatment process thus suggests that removal technique should be developed. In this study, one reverse osmosis (RO) membrane, two nanofiltration (NF) membranes and two ultrafiltration (UF) membranes were tested to reject PFHxA (100 - 300 ng/L) in pure water. The measured molecular weight cut-off (MWCO) of two NF membranes were as large as 10,000 and 27,000 Da, while they were still able to reject 96.3% and 95.3% PFHxA in pure water, respectively. This indicates PFHxA rejection rate was not dependent on the MWCO of membrane. Results also show that membrane with more negative zeta-potential tends to have higher rejection rate to PFHxA in pure water, suggesting that electrical repulsion between PFHxA and membrane might play an important role in PFHxA rejection. In conclusion, NF membranes would be a better option for removing PFHxA from drinking water than RO membrane because of their larger pure water permeability and NaCl transmission. © 2017 Japan Society on Water Environment.

Abstract  Perfluoroalkyl substances (PFAS) are surface-active agents used in diverse industrial and commercial applications. PFAS contaminate both freshwater and marine ecosystems, are highly persistent and accumulate through trophic transfer. Seabirds are exposed to environmental contaminants due of their high trophic position in food webs and relatively long lifespan. We measured levels of ten perfluoroalkyl acids (PFAAs) in egg yolks of yellow-legged gulls (Larus michahellis) breeding in the northern Adriatic sea (NE Italy). We examined PFAAs variation within clutches (between eggs of different laying order) and among clutches. Perfluorooctane sulfonate (PFOS) was the most abundant yolk PFAA (mean = 42.0 ng/g wet weight), followed by perfluorooctanoic acid (PFOA; 3.8 ng/g ww) and perfluorododecanoic acid (PFDoDa; 2.8 ng/g ww). ƩPFAAs averaged57.4 ng/g ww, ranging between 26.5 and 115.0 ng/g ww. PFAA levels varied substantially among clutches (0.29 - 0.79 of total variation), whereas the effects of laying order were considerably weaker (0.01 - 0.13). Egg laying order effects were detected for ƩPFAAs, PFOS, perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDA), perfluoroundecanoic acid (PFUnA) and PFDoDa, whereby the last-laid eggs exhibited lower PFAAs concentrations than early-laid eggs. Our results indicate that seagulls from the northern Adriatic basin deposit measurable amounts of PFAAs in their eggs. The large among-clutches differences in PFAAs suggest that exposure of yellow-legged gull females to these compounds is highly variable. This article is protected by copyright. All rights reserved.

Abstract  Breast cancer (BC) is a common cancer in women worldwide; however, the incidence of BC is increasing in younger women, possibly associated with the environment. Perfluoroalkyl substances (PFAS) are one of endocrine disruptors that accumulate in environment and impact human health. This study aimed to investigate whether the PFAS and BC are associated. We enrolled 120 BCE patients and 119 controls at National Taiwan University Hospital (NTUH) and also collected bio-specimen and questionnaire from 2013 to 2015. All subjects' plasma PFAS levels were analyzed by ultra-performance liquid chromatography tandem mass spectrometry method with electrospray ionization (UHPLC-ESI-MS/MS). A logistic regression model was used to estimate the association between PFAS and BC. In the ≤50 years age group, the adjusted odds ratio (OR) was 2.34 (95% CI = 1.02, 5.38) for perfluorooctane sulfonate (PFOS) exposure per natural log unit increase. After stratifying the estrogen receptor (ER) status and age group, we obtained a positive association for PFHxS and PFOS concentrations with respect to the risk of ER positive tumors for ≤50 years age group. In conclusion, we found that PFAS were associated with the BC risk of ER positive tumors in young Taiwanese women. Further studies are needed to follow and explore whether these associations are causal.

Abstract  Research pertaining to exposure of humans to per- and polyfluorinated alkyl substances (PFASs) has received considerable public and regulatory attention in recent years. Although several studies have reported exposure to PFASs by populations in North America and western Europe, such information is still scarce in Latin America, including Brazil. In this study, concentrations of thirteen PFASs were determined in whole blood collected during the second trimester from 252 pregnant Brazilian women. This is a nested case-control study within the Brazilian Ribeirao Preto and Sao Luiz Birth Cohort Study (BRISA) with selected birth outcomes cases (n = 63) and matched controls (n = 189). PFASs concentrations were associated with conditions including preeclampsia, birth weight (BW), preterm birth, and intrauterine growth restriction (IUGR). Among PFASs measured, perfluorooctane sulfonate (PFOS) was found at the highest concentration (range: 1.06-106 ng mL-1 with a median value of 3.41 ng mL-1) which was followed by perfluorooctanoic acid (PFOA, range: 0.11-2.77 ng mL-1 with a median value of 0.20 ng mL-1). A significant positive association of PFOS and PFOA concentrations with fetal growth restriction (p < 0.05) was found. This is the first study to assess whole blood concentrations of PFASs and their effect on fetal growth in pregnant Brazilian women.

Abstract  Twelve perfluoroalkyl substances (PFASs) were analyzed in tap waters collected from 10 different cities in Sichuan Province using an ultra-high performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). The results show that ∑PFASs in Yibin area displayed the highest concentration level at 41.2 ng•L-1, while Mianyang had the lowest concentration (4.17 ng•L-1). Perfluroroocantanoic acid (PFOA) was the predominant PFASs in tap waters of Sichuan Province, which accounted for 28%~89% of ∑PFASs with an exception of Yibin (8.6%), followed by perfluorohexanoate (PFHxA), perfluorooctane sulfonate (PFOS) and perfluorononanoate (PFNA). It suggests that short- and median-chain PFASs (C≤10) were the main contaminants in tap water. Finally, risk quotients (RQs) were calculated and it was found that RQs values of PFOA, PFOS, PFHxS, PFBS and PFHxA were lower than 1 in all the tap waters, suggesting no direct health risk to local residents. © 2019, Science Press. All right reserved.

Abstract  In Volume 30, in the article, “Six Pilot-Scale Studies Evaluating the In Situ Treatment of PFAS in Groundwater” by Rick McGregor the following changes were made 1)In the abstract the units for the concentration of various PFAS compounds were reported as ug/L, they should be ng/L and read: “24,000 ng/L perfluoropentanoic acid (PFPeA), up to 6,200 ng/L pentafluorobenzoic acid (PFBA), 16,100 ng/L perfluorohexanoic acid (PFHxA), up to 6,080 ng/L perfluoroheptanoic acid (PFHpA), up to 450 ng/L perfluorooctanoic acid (PFOA) and up to 140 ng/L perfluorononanoic acid (PFNA)” 2)In the abstract pentafluorobenzoic acid should be read “perfluorobutanoic acid” 3)On page 41 pentafluorobenzoic acid should be changed to “perfluorobutanoic acid”. These errors were introduced during the writing process and do not affect any of the results presented. © 2020 Wiley Periodicals LLC

Abstract  Contamination profiles of 11 kinds of perfluorinated compounds (PFCs) were analyzed by using ultra high performance liquid chromatography-triple quadrupole mass spectrometry in water and sediment samples of Hanjiang River in dry and wet seasons. The results showed that 11 kinds of PFCs were all detected. The total concentrations of PFCs in water and sediment were 0.3-23.04 ng/L, 0-55.1 ng/g in dry season and 0.16-19.68 ng/L, 0.99-85.07 ng/g in wet season. The maximum concentration of PFCs was detected in Wuhan where Hanjiang River feeds into Yangtze River. Meanwhile, Wuhan had the highest concentration of perfluorooctanoic acid (PFOA) with 22.52 ng/L in dry season and 12.52 ng/L in wet season. Perfluoroheptanoic acid (PFHpA) and perfluorohexanoic acid (PFHxA) were the dominant PFCs in sediment and the highest total concentration of PFCs was detected in Taocha. There was little difference in the concentration composition of ∑PFCs in sediment in both seasons. The risk quotient method was used for the ecological risk assessment of PFOA, perfluorooctane sulfonic acid (PFOS), perfluorononanoic acid (PFNA), PFHxA and perfluorodecanoic acid (PFDA) in water, and PFOA and PFOS in sediment based on the measured environmental concentration (MEC) and the predicted non-effect concentration (PNEC) of target pollutants. The assessment results suggest that the above PFCs in water and sediment of Hanjiang River posed no ecological risk to environment. © 2017 Peking University.

Abstract  Aerobic biotransformation of 6-2 fluorotelomer alcohol (6-2 FTOH, F(CF2)6CH2CH2OH) was studied in a closed bottle system with activated sludge for the first time. The concentrations of 6-2 FTOH and metabolites were determined during the test period (28 days) and biodegradation rates at each sampling time were calculated. The target compounds were not only measured in activated sludge and water phase, but also in headspace and septa because the parent compound and some metabolites are highly volatile. The results indicated that 6-2 FTOH was ready to degrade in activated sludge, and the half-time of 6-2 FTOH was 0.9 day. Large quantity of 6-2 fluorotelomer carboxylic acid (6-2 FTCA) and 6-2 fluorotelomer unsaturated carboxylic acid (6-2 FTUCA) were produced at the beginning of experiment, and their molar yields were 25.4% and 10.8% at 24 h, respectively. Along with the degradation, 6-2 FTCA and 6-2 FTUCA were further transformed to other metabolites with the final molar yields of 0% and 1.2%, respectively. 5-3 polyfluorinated acid (5-3 FTCA) and 5-2 secondary fluorotelomer alcohol (5-2s FTOH) were the primary metabolites at 28 d and their molar yields were 23.4% and 17.6%, respectively. The final molar yield of perfluorohexanoic acid (PFHxA) was 1.3%, which was lower than that in soil or mixed bacteria culture system in other studies. At Day 28, 5.5% of 6-2 FTOH were still detectable in the closed bottle system. Based on the results of this study, monitoring and toxicity test on the stable metabolites of FTOH degradation should be strengthened so as to make a comprehensive risk assessment of 6-2 FTOH.

Abstract  In order to assess the feasibility of typical plants as bioindicators for perfluorinated chemicals (PFCs), the residues of 13 PFCs in fresh leaves of moss, camphor tree, masson pine, gladiolus, lichen, alfalfa, silky oak and rhododendron were measured by high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). Moss, which accumulates PFCs most effectively among the eight, was selected as the environmental bioindicator for PFCs assessment. The total fluorine, extractable organic fluorine and PFCs in moss from 12 locations of six Shenzhen districts, including Bao'an, Nanshan, Futian, Yantian, Luohu and Longgang, were measured by cyclic neutron activation analysis combined with HPLC-MS/MS. Results showed that EOF accounted for 13.4%-16.5% of TF. They indicated that inorganic fluorine was the main form. Only 0.08%-0.15% of EOF was the identified fluorine while more than 99.8% of EOF required further identification. The sum of perfluorooctane sulfonate, perfluorooctanoic acid and perfluorohexanoic acid accounted for 88%-99% of total PFCs, making them the main PFCs species in moss. Total PFCs residues in moss from Bao'an district were significantly higher than those from other districts (P<0.01), which was likely due to the presence of PFCs-related industries, geographical location and climate. The results suggest that moss is a feasible bioindicator for PFCs and its exposure risk in the environment.

Abstract  A discussion on the environmental fate of fluorosurfactants covers the development and use of aqueous film forming foams for extinguishing hazardous hydrocarbon-fuel fires; development of an analytical method to quantitatively determine perfluorinated surfactants in groundwater; application of the method in analyzing sets of groundwater samples from abandoned fire-training areas in military installations around the US (Naval Air Station Fallon, NV; Tyndall Air Force Base (AFB); and Wurtsmith AFB); derivatization of the perfluorocarboxylates by the solid phase extraction and the in-vial elution and derivatization technique; and the detection of perfluorocarboxylates (perfluorohexanoate, perfluoroheptanoate, and perfluorooctanoate) from groundwater analyses of samples, showing proof that this class of perfluorinated surfactants is not readily biodegradable.

Abstract  With this Correction, we would like to improve the specificity in our per- and polyfluoroalkyl substances (PFASs) terminology. PFASs are either nondegradable or degrade to form nondegradable terminal degradation products, usually (although not always) the perfluoroalkyl or perfluoroalkyl(poly)ether acids (collectively termed PFAAs by Wang et al.1). Our focus lies on the perfluoroalkyl acids, and it is those that are referred to in the published paper when the abbreviation PFAA is used. Our framework covers nonpolymeric and polymeric perfluoroalkane-sulfonyl-fluoride- (PASF-) and fluorotelomer-based PFASs. The polymeric substances included in the framework are the side-chain fluorinated polymers that are considered precursors to PFAAs. The nonpolymeric substances included in our framework are the low-molecular-weight precursors to PFAAs and the PFAAs themselves. The substances covered by our framework are summarized in Table 1 of the published paper. Fluoropolymers or perfluoropolyethers were not considered in our framework. For example, we would like to point out that in the statement that our LCIA framework can be applied to the “vast majority of PFASs on the market”, and elsewhere in the article, we were not considering fluoropolymers or perfluoropolyethers, which comprise a significant production volume fraction of the PFASs on the market. Consideration of the LCIA of a wider range of PFASs, including fluoropolymers and perfluoropolyethers, would be a valuable extension of our framework. Furthermore, in Section 3.3, it was stated that no emissions of PFASs were included in the commercial LCI data set. Whereas emissions of shorter chain perfluoroalkyl substances were included (with one to three carbon atoms), emissions of PFHxA and its precursors were not. We would also like to clarify that f in eq 2 is a mass fraction, as the characterization factor (CF) is expressed per kilogram emitted. In Table 1, the transformation fraction is given as a molar yield, which is to be transformed into a mass yield. In footnote a in Table 1, this is described as the weight fraction of the primary pollutant that is made up of the PFAA. A clearer description would be that the quotient between the molar weights (M (g/mol)) of the precursor (the primary pollutant) and the PFAA is to be applied. Note that when the primary pollutant x is a side-chain fluorinated polymer, the M of the repeating unit is applied. This has been clarified in a corrected version of the Supporting Information (SI). In addition, the SI was made consistent with model calculations: Table S15 was updated to reflect the fact that LCI data for the DWR-treated drape are per square meter not per kg textile (correspondingly, the C6 copolymer amount per functional unit reported in the main paper (Section 3.3) should be 0.001 kg), Section S4.1.2 was updated with a corrected formula, Sections S5.1 and S5.3 were updated with the correct KDOC, and Section S5.4 was updated with relevant information regarding PFOS. © 2020 American Chemical Society. All rights reserved.

Abstract  Per- and polyfluoroalkyl substances (PFASs) are today considered important constituents of the continuously growing substance group of persistent contaminants of emerging environmental concern (PCEC). Here, we report for the first time the concentrations of 12 relevant PFASs in 28 marine water samples from the Saudi Arabian coastal waters of the Red Sea. The sum levels of 12 PFASs (sigma(12)PFAS) in surface seawater ranged from

Abstract  The present study was aimed at the development of a strategy for removing and degrading perfluorohexanoic acid (PFHxA) from industrial process waters at concentrations in the range 60-200 mg L(-1). The treatment train consisted of nanofiltration (NF) separation followed by electrochemical degradation of the NF concentrate. Using a laboratory-scale system and working in the total recirculation mode, the DowFilm NF270 membrane provided PFHxA rejections that varied in the range 96.6-99.4% as the operating pressure was increased from 2.5 to 20 bar. The NF operation in concentration mode enabled a volume reduction factor of 5 and increased the PFHxA concentration in the retentate to 870 mg L(-1). Results showed that the increase in PFHxA concentration and the presence of calcium sulfate salts did not induce irreversible membrane fouling. The NF retentate was treated in a commercial undivided electrochemical cell provided with two parallel flow-by compartments separated by bipolar boron doped diamond (BDD) electrode, BDD counter anode, and counter cathode. Current densities ranging from 20 to 100 A m(-2) were examined. The electrochemical degradation rate of PFHxA reached 98% and was accompanied by its efficient mineralization, as the reduction of total organic carbon was higher than 95%. Energy consumption, which was 15.2 kWh m(-3) of treated NF concentrate, was minimized by selecting operation at 50 A m(-2). While most of the previous research on the treatment of perfluoroalkyl substances (PFASs) focused on the removal of perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS), these compounds have been phased out by chemical manufacturers. Our findings are relevant for the treatment of PFHxA, which appears to be one of the present alternatives to long-chain PFASs thanks to its lower bioaccumulative potential than PFOA and PFOS. However, PFHxA also behaves as a persistent pollutant. Moreover, our results highlight the potential of combining membrane separation and electrochemical oxidation for the efficient treatment of PFAS-impacted waters.

Abstract  Human exposure to perfluoroalkyl substances (PFASs) occurs primarily via dietary intake and drinking water. In this study, 16 PFASs have been assessed in 96 drinking waters (38 bottled waters and 58 samples of tap water) from Brazil, France and Spain. The total daily intake and the risk index (RI) of 16 PFASs through drinking water in Brazil, France and Spain have been estimated. This study was carried out using an analytical method based on an online sample enrichment followed by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). The quality parameters of the analytical method were satisfactory for the analysis of the 16 selected compounds in drinking waters. Notably, the method limits of detection (MLOD) and method limits of quantification (MLOQ) were in the range of 0.15 to 8.76ng/l and 0.47 to 26.54ng/l, respectively. The results showed that the highest PFASs concentrations were found in tap water samples and the more frequently found compound was perfluorooctanesulfonic acid (PFOS), with mean concentrations of 7.73, 15.33 and 15.83ng/l in French, Spanish and Brazilian samples, respectively. In addition, PFOS was detected in all tap water samples from Brazil. The highest level of PFASs contamination in a single sample was 140.48ng/l in a sample of Spanish tap water. In turn, in bottled waters the highest levels were detected in a French sample with 116ng/l as the sum of PFASs. Furthermore, the most frequent compounds and those at higher concentrations were perfluoroheptanoic acid (PFHpA) with a mean of frequencies in the three countries of 51.3%, followed by perfluorobutanesulfonic acid (PFBS) (27.2%) and perfluorooctanoic acid (PFOA) (23.0%). Considering that bottled water is approximately 38% of the total intake, the total PFASs exposure through drinking water intake for an adult man was estimated to be 54.8, 58.0 and 75.6ng/person per day in Spain, France and Brazil, respectively. However, assuming that the water content in other beverages has at least the same levels of contamination as in bottled drinking water, these amounts were increased to 72.2, 91.4 and 121.0ng/person per day for an adult man in Spain, France and Brazil, respectively. The results of total daily intake in different gender/age groups showed that children are the most exposed population group through hydration with maximum values in Brazil of 2.35 and 2.01ng/kg body weight (BW)/day for male and female, respectively. Finally, the RI was calculated. In spite of the highest values being found in Brazil, it was demonstrated that, in none of the investigated countries, drinking water pose imminent risk associated with PFASs contamination.

Abstract  This study provides the first evidence on the influence of the semiconductor and electronics industries on perfluorinated chemicals (PFCs) contamination in receiving rivers. We have quantified ten PFCs, including perfluoroalkyl sulfonates (PFASs: PFBS, PFHxS, PFOS) and perfluoroalkyl carboxylates (PFCAs: PFHxA, PFHpA, PFOA, PFNA, PFDA, PFUnA, PFDoA) in semiconductor, electronic, and optoelectronic industrial wastewaters and their receiving water bodies (Taiwan's Keya, Touchien, and Xiaoli rivers). PFOS was found to be the major constituent in semiconductor wastewaters (up to 0.13 mg/L). However, different PFC distributions were found in electronics plant wastewaters; PFOA was the most significant PFC, contributing on average 72% to the effluent water samples, followed by PFOS (16%) and PFDA (9%). The distribution of PFCs in the receiving rivers was greatly impacted by industrial sources. PFOS, PFOA and PFDA were predominant and prevalent in all the river samples, with PFOS detected at the highest concentrations (up to 5.4 microg/L).

Abstract  Biotransformation of 6:2 FTOH [F(CF2)6CH2CH2OH] by the white-rot fungus, Phanerochaete chrysosporium, was investigated in laboratory studies. 6:2 FTOH is a raw material increasingly being used to replace products that can lead to long-chain perfluoroalkyl carboxylic acids (PFCAs, ≥ 8 carbons). During a product's life cycle and after final disposal, 6:2 FTOH-derived compounds may be released into the environment and potentially biotransformed. In this study, P. chrysosporium transformed 6:2 FTOH to perfluorocarboxylic acids (PFCAs), polyfluorocarboxylic acids, and transient intermediates within 28 days. 5:3 Acid [F(CF2)5CH2CH2COOH] was the most abundant transformation product, accounting for 32-43 mol % of initially applied 6:2 FTOH in cultures supplemented with lignocellulosic powder, yeast extract, cellulose, and glucose. PFCAs, including perfluoropentanoic (PFPeA) and perfluorohexanoic (PFHxA) acids, accounted for 5.9 mol % after 28-day incubation. Furthermore, four new transformation products as 6:2 FTOH conjugates or 5:3 acid analogues were structurally confirmed. These results demonstrate that P. chrysosporium has the necessary biochemical mechanisms to drive 6:2 FTOH biotransformation pathways toward more degradable polyfluoroalkylcarboxylic acids, such as 5:3 acid, with lower PFCA yields compared to aerobic soil, sludge, and microbial consortia. Since bacteria and fungi appear to contribute differently toward the environmental loading of FTOH-derived PFCAs and polyfluorocarboxylic acids, wood-rotting fungi should be evaluated as potential candidates for the bioremediation of wastewater and groundwater contaminated with fluoroalkyl substances.

Abstract  The sorption of perfluoroalkyl substances (PFASs) was investigated for two model soil mineral surfaces, alumina (Al2O3) and silica (SiO2), on molecular level using neutron scattering. The PFASs were selected (i.e. perfluorohexanoic acid (PFHxA), perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), and perfluorooctane sulfonic acid (PFOS)) to examine the role of hydrophobic chain length and hydrophilic functional group on their sorption behaviour. All four PFASs were found to sorb to alumina surface (positively charged) forming a hydrated layer consisting of 50% PFASs. The PFAS solubility limit, which decrease with chain length, was found to strongly influence the sorption behaviour. The sorbed PFAS layer could easily be removed by gentle rinsing with water, indicating release upon rainfall in the environment. No sorption was observed for PFOA and PFOS at silica surface (negatively charged), showing electrostatic interaction being the driving force in the sorption process.