Perfluoroalkylated Substances Research Articles

Simultaneous Transformation of Commingled Trichloroethylene, Tetrachloroethylene, and 1,4-Dioxane by a Microbially Driven Fenton Reaction in Batch Liquid Cultures.

A microbially driven Fenton reaction system [driven by the Fe(III)-reducing facultative anaerobe S. oneidensis] was reconfigured to transform source zone levels of TCE, PCE, and 1,4-dioxane as single contaminants or as binary and ternary mixtures. The microbially driven Fenton reaction may thus be applied as an ex situ platform for simultaneous degradation of at least three (and potentially more) commingled contaminants. Additional targets for ex situ and in situ degradation by the microbially driven Fenton reaction developed in the present study include multiple combinations of environmental contaminants susceptible to attack by Fenton reaction-generated HO˙ radicals, including commingled plumes of 1,4-dioxane, pentachlorophenol (PCP), PCE, TCE, 1,1,2-trichloroethane (TCA), and perfluoroalkylated substances (PFAS).

Perfluoroalkylated substances in edible livers of farm animals, including depuration behaviour in young sheep fed with contaminated grass

Perfluoroalkylated substances (PFASs) present a potential health risk for consumers. In animals these compounds are known to accumulate in livers. In order to determine potential PFASs contamination in commercially available livers, samples from farmed sheep, horses, cows, pigs and chicken were collected from the Dutch market. PFOS was the only detectable PFAS and its concentration was higher in free ranging animals like cows and sheep. The detected levels of PFOS in the liver samples were very low (up to 4.5 ng g−1 ww).To further study the kinetic behaviour in foraging animals, samples from a study in which sheep were fed with grass obtained from a river floodplain, were examined. PFOS was the only detectable PFAS in the contaminated grass pellets, showing a level of about 0.5 μg kg−1. Young blackhead sheep were fed with either clean or contaminated grass for a period up to 112 days. A time-dependent increase in liver PFOS concentrations was observed from 2.4 to 10.9 ng g−1 ww after 8 and 112 days respectively. A time-dependent depuration was observed in livers of animals switched to clean grass after 56 days of exposure, from 9.2 to 4.7 ng g−1 ww after 64 and 112 days respectively. The percentage of PFOS ingested from the grass and retained in the liver was estimated to be 12% at day 56, and decreased gradually to 6% after 56 days on clean grass, showing that the decrease in levels is not only caused by an increase in liver weight.Levels detected in commercial livers but also those in the sheep study would not lead to exceedance of the current TDI for PFOS set by EFSA. Therefore, it can be assumed that they do not present a risk for human health.

Pollutants monitoring and air quality evaluation in a confined environment: The ‘Majesty’ of Ambrogio Lorenzetti in the St. Augustine Church in Siena (Italy)

A monitoring campaign of the levels of some organic contaminants, such as polycyclic aromatic hydrocarbons (PAHs), perfluoro alkylated substances (PFASs), chlorinated pesticides (4 isomers of hexachlorocyclohexane, hexachlorobenzene, 6 isomers and metabolites of DDT and dieldrin), polychlorinated biphenyls (PCBs), and polybrominated diphenyl ethers (PBDEs), in different matrices (dust taken from the floor and under a wall painting and fragments of the ‘Majesty’ wall painting by Ambrogio Lorenzetti), was conducted in the historical museum of St. Augustine's church in Siena (Italy). Instrumental analyses were made by gas chromatography and liquid chromatography coupled with mass spectrometry. The results showed the presence of some organic pollutants (PAHs and PBDEs), whose interaction with the surfaces of works of art are not yet fully elucidated. The study was complemented by monitoring the air quality inside and outside the church for the detection of volatile organic compounds (VOCs); all the results showed low levels of air pollution.

Perfluoroalkylated Substance Effects in Xenopus laevis A6 Kidney Epithelial Cells Determined by ATR-FTIR Spectroscopy and Chemometric Analysis.

The effects of four perfluoroalkylated substances (PFASs), namely, perfluorobutanesulfonate (PFBS), perfluorooctanoic acid (PFOA), perfluorooctanesulfonate (PFOS), and perfluorononanoic acid (PFNA) were assessed in Xenopus laevis A6 kidney epithelial cells by attenuated total reflection Fourier-transform infrared (ATR-FTIR) spectroscopy and chemometric analysis. Principal component analysis–linear discriminant analysis (PCA-LDA) was used to visualize wavenumber-related alterations and ANOVA-simultaneous component analysis (ASCA) allowed data processing considering the underlying experimental design. Both analyses evidenced a higher impact of low-dose PFAS-treatments (10–9 M) on A6 cells forming monolayers, while there was a larger influence of high-dose PFAS-treatments (10–5 M) on A6 cells differentiated into dome structures. The observed dose–response PFAS-induced effects were to some extent related to their cytotoxicity: the EC50-values of most influential PFAS-treatments increased (PFOS < PFNA < PFOA ≪ PFBS), and higher-doses of these chemicals induced a larger impact. Major spectral alterations were mainly attributed to DNA/RNA, secondary protein structure, lipids, and fatty acids. Finally, PFOS and PFOA caused a decrease in A6 cell numbers compared to controls, whereas PFBS and PFNA did not significantly change cell population levels. Overall, this work highlights the ability of PFASs to alter A6 cells, whether forming monolayers or differentiated into dome structures, and the potential of PFOS and PFOA to induce cell death.

Perfluoroalkylated substances (PFASs) and legacy persistent organic pollutants (POPs) in halibut and shrimp from coastal areas in the far north of Norway: Small survey of important dietary foodstuffs for coastal communities

Halibut (Hippoglossus hippoglossus) and shrimps (Pandalus borealis) are regular foodstuffs for communities in northern Norway and important species for the coastal fishing industry. This is the first study to present a comprehensive overview of the contaminant status of these species, with emphasis on unregulated perfluoroalkylated substances (PFAS). The contaminant concentrations were low and within tolerable levels for human dietary exposure. Median Σpolychlorinated biphenyls (PCB) were 4.9 and 2.5ng/g ww for halibut and unpeeled shrimps, respectively. Concentrations of perfluorooctane sulfonate (PFOS) – the most abundant PFASs – were 0.9 and 2.7ng/g ww in halibut and shrimp, respectively. The halibut fillets were dominated by PCBs, which contributed to 50% of the total POPs load, followed by ΣDDTs; 26% and PFASs (18%), whereas shrimps were dominated by PFASs (74%). ΣPBDEs (polybrominated diphenyl ethers) contributed to 1–4% of the total POP load. Local sources are not contributing significantly to the contaminant burden in these species.

Use of strong anion exchange resins for the removal of perfluoroalkylated substances from contaminated drinking water in batch and continuous pilot plants

In recent years abnormally high levels of perfluoroalkylated substances (PFAS) have been detected both in surface and underground water sampled in an area covering approximately 150 square kilometers in the Veneto region (Italy) indicating the presence of a pollution point source (fluorochemicals production plant). Adsorption on granular activated carbon is an emergency measure which is poorly effective requiring frequent replacement. This work focuses on the application of three strong anion exchange resins (Purolite® A520E, A600E and A532E) for the removal of traces of PFOA, PFOS, PFBA and PFBS (concentration of hundreds of ng L−1) from drinking water. This technology is attractive for the possibility of reusing resins after an in-situ regeneration step.A strong relationship between the hydrophobicity of the exchange functional group of the resin and its capacity in removing PFAS exists. A600E (non hydrophobic) and A520E (fairly hydrophobic) show a reduced sorption capacity compared to A532E (highly hydrophobic). While A600E and A520E can be regenerated with solvent-less dilute solutions of non-toxic NH4Cl and NH4OH, A532E requires concentrated solutions of methanol or ethanol and 1% NH4Cl and for the sake of this work it was regarded as non-regenerable. The volume of regeneration effluents requiring incineration can be efficiently reduced by more than 96.5% by using reverse osmosis coupled with under-vacuum evaporation.Transmission electron analysis on saturated resins showed that large molecular macro-aggregates of PFAS can form in the intraparticle pores of resin indicating that ion exchange is not the only mechanism involved in PFAS removal.

Perfluoroalkylated substances (PFASs) in home and commercially produced chicken eggs from the Netherlands and Greece.

Dietary intake is a major route of human exposure to perfluoroalkylated substances (PFASs). However, the available information on PFAS levels in food, including chicken eggs, is limited. In the present study, home produced and commercially produced eggs (organic, battery and free range eggs) were collected from the Netherlands (n = 95) and Greece (n = 76). The egg yolks were analysed for 11 PFASs by liquid chromatography-tandem mass spectrometry using isotope dilution. PFAS levels in yolk were higher in home produced eggs from the Netherlands (median 3.1, range < LOQ - 31.2 ng g(-1)) and Greece (median 1.1, range < LOQ - 15.0 ng g(-1)) compared to the eggs collected from supermarkets. In these eggs, all PFAS levels were below the LOQ of 0.5 ng g(-1), except for a small amount of perfluorooctane sulfonate (PFOS) in 1 sample in each country (1.1 ng g(-1) and 0.9 ng g(-1) for the Netherlands and Greece respectively). PFOS was the predominant PFAS, making up on average 85% of ∑PFASs. The highest PFOS concentration was detected in a Dutch home produced egg sample (24.8 ng g(-1)). The contamination pattern was similar in both countries with the long-chain PFASs (C ≥ 8) being most frequently detected, while short-chain PFASs were rarely found. The most likely cause of the contamination of home produced eggs is ingestion of soil through pecking. Although regular consumption of home produced eggs will lead to an increased PFOS exposure, it is not expected that it will lead to exceedance of the tolerable daily intake established by EFSA.

Determination of perfluoroalkylated substances (PFASs) in drinking water from the Netherlands and Greece

In the present study 11 perfluoroalkylated substances (PFASs) were analysed in drinking tap water samples from the Netherlands (n = 37) and from Greece (n = 43) by applying LC-MS/MS and isotope dilution. PFASs concentrations above the limit of quantification, LOQ (0.6 ng/l) were detected in 20.9% of the samples from Greece. Total PFAS concentrations ranged between <LOQ and 5.9 ng/l, with the highest concentrations noted for the three Aegean islands Mykonos, Kalymnos and Syros and for the town Tripoli in the Peloponnese. In the Dutch situation, total PFASs concentrations above the LOQ were detected in 48.6% of the samples, varying from <LOQ to 54 ng/l. The highest concentrations were detected around Amsterdam (including Schiphol airport) and more generally, PFASs were detected in the drinking water from the western part of the Netherlands. This seems attributable to the source, which is purified surface water in this area. Short-chain PFASs and especially perfluoropentanoic acid (PFPeA), perfluorohexanoic acid (PFHxA), perfluoroheptanoic acid (PFHpA), perfluorooctanoic acid (PFOA), perfluorobutane sulfonate (PFBS), and perfluorohexane sulfonate (PFHxS) were detected most frequently, whereas long-chain PFASs (C > 8) were only rarely detected. In the drinking water samples from the eastern part of the Netherlands, where drinking water is sourced from groundwater reservoirs, no PFASs were detected. This demonstrates that exposure to PFASs through drinking water in the Netherlands is dependent on the source. Additionally, five samples of bottled water from each country were analysed in the current study, with all of them originating from ground wells. In these samples, all PFASs were below the LOQ.

Organohalogenated contaminants in white-tailed eagle (Haliaeetus albicilla) nestlings: An assessment of relationships to immunoglobulin levels, telomeres and oxidative stress

Biomagnifying organohalogenated compounds (OHCs) may have adverse effects on the health of birds, especially marine avian top predators that accumulate high OHC loads. Contaminants may impair the humoral immunity and also influence the antioxidant enzyme activity (i.e. oxidative stress). Moreover, physical conditions and oxidative stress during development may reduce telomere lengths, one of the main mechanisms explaining cell senescence. To examine the potential effects of environmental contaminants on physiological biomarkers of health, OHCs with different ‘physicochemical’ properties were related to immunoglobulin Y levels (IgY; humoral immunity), superoxide dismutase enzyme (SOD) activity in blood plasma, and telomere length (measured in red blood cells) in individual 7–8weeks old nestlings (n=35) of white-tailed eagles (Haliaeetus albicilla) in the Norwegian Sub-Arctic. Different organochlorines (OCs) and perfluoroalkylated substances (PFASs) were measured in blood plasma of nestlings, demonstrating higher concentrations of the emerging contaminants (PFASs), notably perfluorooctane sulfonate (PFOS), compared to legacy OCs. There were no relationships between the contaminant loads and plasma IgY levels. Moreover, differences between years were found for telomere lengths, but this was not related to contaminants and more likely a result of different developmental conditions. However, there were significant and negative relationships between the OC loadings and the SOD activity. This suggests that some legacy OCs challenge the antioxidant capacity in nestlings of white-tailed eagles.

Perfluorinated chemicals in blood serum of inhabitants in central Poland in relation to gender and age

The goal of this paper is to determine concentrations of seven selected perfluoroalkylated substances (PFASs): perfluorooctane sulfonic acid (PFOS), perfluorooctanoic acid (PFOA), perfluorohexane sulfonic acid (PFHxS), perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDA), perfluoroundecanoic acid (PFUnDA), perfluorododecanoic acid (PFDoDA) in the blood serum of men and women of reproductive age from the central region of Poland. The relation between sex of tested subjects and the levels of compounds in blood serum of humans will also be considered and analysed as an element of the risk assessment. The study was made on the blood serum samples collected from 253 women and 176 men of reproductive age between 20 and 44years from Warsaw and surrounding areas. Higher concentrations of five (PFOS, PFOA, PFNA, PFDA, PFUnDA) from among seven selected PFASs were observed in men in comparison to women from the same populations. Only the concentrations of PFHxS and PFDoDA were slightly higher in women than in men. These differences were statistically significant in all cases, except for PFUnDA. The hypothesis that the concentrations of said compounds increase with age of the test subjects, regardless of gender has not been confirmed.

Perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA): emerging contaminants of increasing concern in fish from Lake Varese, Italy.

Perfluoroalkylated substances (PFASs) are highly fluorinated aliphatic compounds with high thermal and chemical stability, used in a range of industrial applications. Extensive screening analyses in biota samples from all over the world have shown the bioaccumulation of PFAS into higher trophic levels in the food chain. Perfluorooctane sulfonic acid (PFOS) and perfluoroctanoic acid (PFOA) are potential reproductive and developmental toxicants and are considered to be emerging endocrine disrupters. Ingestion of fish and other seafood is considered the main source of exposure of these contaminants. Here, we quantified PFOS and PFOA by LC-MS/MS in muscle samples of European perch from Lake Varese, Italy. PFOS was detected in all samples with concentrations of up to 17.2ngg(-1). Although the reported values were lower than the recommended total daily intake (TDI) proposed by the European Food Safety Authority (EFSA), fish from Lake Varese may be a significant source of dietary PFOS exposure.

Food intake and serum persistent organic pollutants in the Greenlandic pregnant women: The ACCEPT sub-study

The Greenlandic Inuit have high blood concentrations of environmental persistent organic pollutants (POPs). High POP concentrations have been associated with age, smoking and consumption of marine mammals. Studies have indicated that exposure to POPs during pregnancy may adversely affect fetal and child development.To assess geographical differences in diet, lifestyle and environmental contaminant exposure among pregnant women in Greenland, blood samples and questionnaire data were collected from 207 pregnant women in five Greenlandic regions (North, Disco Bay, West, South and East). Blood samples were analyzed for 11 organochlorine pesticides (OCPs), 14 polychlorinated biphenyls (PCBs), 5 polybrominated diphenyl ethers (PBDEs), 15 perfluoroalkylated substances (PFASs) and 63 metals.A trend of higher intake of marine mammals in the East and North regions was reflected by a higher n−3/n−6 fatty acid ratio. Participants in the East region tended also to have higher intake of terrestrial species. A significant higher seabird intake was seen for pregnant women in the West region. Significant regional differences were found for blood concentrations of PCBs, OCPs, PFASs and mercury, with higher levels in the North and East regions. PFASs were significantly associated with PCBs and OCPs in most of the regions. In the North region, PFASs were associated with both selenium and mercury. No significant regional difference was observed for PBDEs.The regional differences of blood levels of POPs and mercury were related to differences in intake of the traditional food. Compared to earlier reports, decreased levels of legacy POPs, Hg and Pb and perfluorooctane sulfonate and perfluorooctanoic acid were observed, but the levels of PFAS congeners perfluorohexane sulfonate and perfluorononanoic acid were sustained. The detection of POPs and heavy metals in maternal blood indicates fetal exposure to these compounds possibly influencing fetal development.

PFOS and PFOA in cereals and fish: Development and validation of a high performance liquid chromatography-tandem mass spectrometry method

Perfluorooctane sulfonate (PFOS) and Perfluorooctanoic acid (PFOA) are environmental contaminants belonging to a chemical group known as perfluoroalkyl substances (PFASs), which are very persistent in the environment. PFASs are potential reproductive and developmental toxicants and are considered to be endocrine disrupters. These compounds have been found with greater frequency in fish and other seafood compared to other food groups. In fact, aquatic ecosystems represent the final reservoir for PFASs due to their high affinity for sedimentary and living organic matter. Recommendation161/2010/EU stated that the Member States should carry out analysis of perfluoroalkylated substances in order to detect the presence of PFOS and PFOA by making use of an analytical method that has been proven to generate reliable results. The LC-MS/MS method described here has been developed for detecting PFOS and PFOA in fish and cereals. Validation of this method resulted in limits of quantification (LOQs) varying from 0.50 μg/kg for PFOA to 0.70 μg/kg for PFOS, fulfilling recoveries (95–109%), and showing a good linearity (R2 = 0.99). Precision varied from 4.43% to 8.97% of repeatability for PFOA and from 6.30% to 12.33% of repeatability for PFOS.

Is the fact of parenting couples cohabitation affecting the serum levels of persistent organohalogen pollutants?

Organohalogen compounds constitute one of the important groups of persistent organic pollutants (POPs). Among them, due to their long-term health effects, one should pay attention on organochlorine pesticides, polychlorinated biphenyls (PCBs) and perfluoroalkylated substances (PFASs). This paper is an attempt to answer the question about relation between the fact of cohabitation by couples expecting a child and the level of the organohalogen compounds in the blood serum of both parents. The study was done on a population of parent couples from Greenland, Poland and Ukraine, from whom blood samples were collected in order to establish the levels of marker organohalogen compounds. We selected, as the representative of these compounds, the most persistent metabolite of DDT, i.e. p,p'-DDE, the most frequently detected PCB congener - CB-153, and PFOS and PFOA as the representatives of PFASs. The results show that in case of all compounds under study the highest concentrations were present always in men in relation to the levels detected in the blood serum of their female partners, regardless of the country of origin of the couple. A positive correlation was noted between the concentrations of the studied compounds in the blood serum of men and women in parenting couples. In some cases these correlations were statistically significant, e.g. for concentrations of p,p'-DDE in pairs from Greenland and Ukraine, of CB-153 in pairs from Poland and Ukraine, and of PFOS for parents from Greenland and Poland, while for PFOA - only for couples from Greenland. The concentrations of the compounds included in the study were similar to the levels found in general population in other countries. Our results show that the exposure to POPs resulting from cohabitation plays a role in the general exposure to these compounds.

An Antarctic research station as a source of brominated and perfluorinated persistent organic pollutants to the local environment.

This study investigated the role of a permanently manned Australian Antarctic research station (Casey Station) as a source of contemporary persistent organic pollutants (POPs) to the local environment. Polybrominated diphenyl ethers (PBDEs) and poly- and perfluoroalkylated substances (PFASs) were found in indoor dust and treated wastewater effluent of the station. PBDE (e.g., BDE-209 26-820 ng g(-1) dry weight (dw)) and PFAS levels (e.g., PFOS 3.8-2400 ng g(-1) (dw)) in dust were consistent with those previously reported in homes and offices from Australia, reflecting consumer products and materials of the host nation. The levels of PBDEs and PFASs in wastewater (e.g., BDE-209 71-400 ng L(-1)) were in the upper range of concentrations reported for secondary treatment plants in other parts of the world. The chemical profiles of some PFAS samples were, however, different from domestic profiles. Dispersal of chemicals into the immediate marine and terrestrial environments was investigated by analysis of abiotic and biotic matrices. Analytes showed decreasing concentrations with increasing distance from the station. This study provides the first evidence of PFAS input to Polar regions via local research stations and demonstrates the introduction of POPs recently listed under the Stockholm Convention into the Antarctic environment through local human activities.

Perfluoroalkylated substances (PFAS) affect oxidative stress biomarkers in vitro

Perfluoroalkylated substances (PFAS) have been widely used since 1950s and humans are exposed through food, drinking water, consumer products, dust, etc. The long-chained PFAS are persistent in the environment and accumulate in wildlife and humans. They are suspected carcinogens and a potential mode of action is through generation of oxidative stress. Seven long-chained PFAS found in human serum were investigated for the potential to generate reactive oxygen species (ROS), induce DNA damage and disturb the total antioxidant capacity (TAC). The tested PFAS were perfluorohexane sulfonate (PFHxS), perfluorooctane sulfonic acid (PFOS), perfluoroctanoic acid (PFOA), perfluorononanoate (PFNA), perfluorodecanoate (PFDA), perfluoroundecanoate (PFUnA), and perfluorododecanoate (PFDoA). Using the human hepatoma cell line (HepG2) and an exposure time of 24h we found that all three endpoints were affected by one or more of the compounds. PFHxS, PFOA, PFOS and PFNA showed a dose dependent increase in DNA damage in the concentration range from 2×10−7 to 2×10−5M determined by the comet assay. Except for PFDoA, all the other PFAS increased ROS generation significantly. For PFHxS and PFUnA the observed ROS increases were dose-dependent. Cells exposed to PFOA were found to have a significant lower TAC compared with the solvent control, whereas a non-significant trend in TAC decrease was observed for PFOS and PFDoA and an increase tendency for PFHxS, PFNA and PFUnA. Our results indicate a possible genotoxic and cytotoxic potential of the PFAS in human liver cells.

Perfluoroalkylated substances in the global tropical and subtropical surface oceans.

In this study, perfluoroalkylated substances (PFASs) were analyzed in 92 surface seawater samples taken during the Malaspina 2010 expedition which covered all the tropical and subtropical Atlantic, Pacific and Indian oceans. Nine ionic PFASs including C6-C10 perfluoroalkyl carboxylic acids (PFCAs), C4 and C6-C8 perfluoroalkyl sulfonic acids (PFSAs) and two neutral precursors perfluoroalkyl sulfonamides (PFASAs), were identified and quantified. The Atlantic Ocean presented the broader range in concentrations of total PFASs (131-10900 pg/L, median 645 pg/L, n = 45) compared to the other oceanic basins, probably due to a better spatial coverage. Total concentrations in the Pacific ranged from 344 to 2500 pg/L (median = 527 pg/L, n = 27) and in the Indian Ocean from 176 to 1976 pg/L (median = 329, n = 18). Perfluorooctanesulfonic acid (PFOS) was the most abundant compound, accounting for 33% of the total PFASs globally, followed by perfluorodecanoic acid (PFDA, 22%) and perfluorohexanoic acid (PFHxA, 12%), being the rest of the individual congeners under 10% of total PFASs, even for perfluorooctane carboxylic acid (PFOA, 6%). PFASAs accounted for less than 1% of the total PFASs concentration. This study reports the ubiquitous occurrence of PFCAs, PFSAs, and PFASAs in the global ocean, being the first attempt, to our knowledge, to show a comprehensive assessment in surface water samples collected in a single oceanic expedition covering tropical and subtropical oceans. The potential factors affecting their distribution patterns were assessed including the distance to coastal regions, oceanic subtropical gyres, currents and biogeochemical processes. Field evidence of biogeochemical controls on the occurrence of PFASs was tentatively assessed considering environmental variables (solar radiation, temperature, chlorophyll a concentrations among others), and these showed significant correlations with some PFASs, but explaining small to moderate percentages of variability. This suggests that a number of physical and biogeochemical processes collectively drive the oceanic occurrence and fate of PFASs in a complex manner.

Selected physicochemical aspects of poly- and perfluoroalkylated substances relevant to performance, environment and sustainability—Part one

The elemental characteristics of the fluorine atom tell us that replacing an alkyl chain by a perfluoroalkyl or polyfluorinated chain in a molecule or polymer is consequential. A brief reminder about perfluoroalkyl chains, fluorocarbons and fluorosurfactants is provided. The outstanding, otherwise unattainable physicochemical properties and combinations thereof of poly and perfluoroalkyl substances (PFASs) are outlined, including extreme hydrophobic and lipophobic character; thermal and chemical stability in extreme conditions; remarkable aptitude to self-assemble into sturdy thin repellent protecting films; unique spreading, dispersing, emulsifying, anti-adhesive and levelling, dielectric, piezoelectric and optical properties, leading to numerous industrial and technical uses and consumer products. It was eventually discovered, however, that PFASs with seven or more carbon-long perfluoroalkyl chains had disseminated in air, water, soil and biota worldwide, are persistent in the environment and bioaccumulative in animals and humans, raising serious health and environmental concerns. Further use of long-chain PFASs is environmentally not sustainable. Most leading manufacturers have turned to shorter four to six carbon perfluoroalkyl chain products that are not considered bioaccumulative. However, many of the key performances of PFASs decrease sharply when fluorinated chains become shorter. Fluorosurfactants become less effective and less efficient, provide lesser barrier film stability, etc. On the other hand, they remain as persistent in the environment as their longer chain homologues. Surprisingly little data (with considerable discrepancies) is accessible on the physicochemical properties of the PFASs under examination, a situation that requires consideration and rectification. Such data are needed for understanding the environmental and in vivo behaviour of PFASs. They should help determine which, for which uses, and to what extent, PFASs are environmentally sustainable.

Breast cancer risk after exposure to perfluorinated compounds in Danish women: a case-control study nested in the Danish National Birth Cohort.

ObjectiveAnimal studies have indicated that perfluoroalkylated substances (PFAS) increase mammary fibroadenomas. A recent case–control study in Greenlandic Inuit women showed an association between the PFAS serum levels and breast cancer (BC) risk. The present study evaluates the association between serum levels of PFAS in pregnant Danish women and the risk of premenopausal BC during a follow-up period of 10–15 years using prospectively collected exposure data during the pregnancy.MethodsQuestionnaire and blood samples were taken during 1996–2002 and at the end of follow-up, all 250 BC cases and 233 frequency-matched controls were chosen for further analyses. Serum levels of ten perfluorocarboxylated acids, five perfluorosulfonated acids, and one sulfonamide (perflurooctane-sulfonamide, PFOSA) were determined by liquid chromatography-tandem mass spectrometry with electrospray ionization in negative mode. Computer-assisted telephone interviews taken during pregnancy provided data on potential confounders. ResultsWeak positive and negative insignificant associations were found between BC risk and levels of perfluorooctane sulfonamide (PFOSA) and perfluorohexanesulfonate (PFHxS), respectively. Grouped into quintile, the BC cases had a significant positive association with PFOSA at the highest quintiles and a negatively association for PFHxS. Sensitivity analyses excluding uncertain cases caused stronger data for PFOSA and weaker for PFHxS. No further significant associations were observed.ConclusionsThis study does not provide convincing evidence for a causal link between PFAS exposures and premenopausal BC risks 10–15 years later.Electronic supplementary materialThe online version of this article (doi:10.1007/s10552-014-0446-7) contains supplementary material, which is available to authorized users.

Is the fresh water fish consumption a significant determinant of the internal exposure to perfluoroalkylated substances (PFAS)?

PFAS are man-made compounds that are highly spread in the environment. Human dietary exposure to such contaminants is of high concern as they may accumulate in the food chain. Different studies already demonstrated the importance of the fish consumption in the dietary exposure of these molecules and the potential increase of internal doses of PFAS following the consumption of PFAS. However, so far few study aimed to study the link between the consumption of fresh water fishes and the internal exposure to PFAS. Objectives of this study were (i) to estimate the internal exposure of populations that are potentially high consumers of fresh water fishes and (ii) to determine whether the consumption of fish caught from fresh water is a significant determinant of the internal exposure of PFAS. In this work, a large sample of adult freshwater anglers from the French metropolitan population (478 individuals) was constituted randomly from participants lists of anglers associations. Questionnaires provided social and demographic information and diet information for each subject. In addition, analyses of blood serum samples provided the internal concentration of 14 PFAS. The survey design allowed to extrapolate the data obtained on the 478 individuals to the freshwater angler population. Descriptive data regarding internal levels of PFAS were discussed at the population level, whereas identification of the determinants were done at the 478 individuals level as sufficient contrast was required in terms of fresh water fish consumption. Only molecules for which the detection frequency were above 80% in blood were considered, i.e., PFOS, PFOA, PFHxS, PFNA, PFHpS, and PFDA. Distribution profiles showed log-normal distribution and PFOS and PFOA were the main contributors of the PFAS sum. For PFOS, the results obtained on the 478 individuals showed that upper percentiles were higher as compared to upper percentiles obtained on occidental general population. This confirmed an over-exposure of a fraction of the 478 individuals. Though, when the results were considered at the population level, the values were close. This was attributed to the low consumption frequency of fresh water fish in the general population. For PFOS, PFNA, PFHxS, PFHpS and PFDA, the fresh water fish consumption was identified as one of the contributors of internal PFAS concentrations. Gender, age, geographical location and consumption of home-grown products as other determinants were also discussed in this paper.