Perfluoroalkyl and polyfluoroalkyl substances (PFASs) in consumer products in Norway – A pilot study

Chemosphere 88 (2012) 980–987

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Perfluoroalkyl and polyfluoroalkyl substances (PFASs) in consumer products in Norway – A pilot study Dorte Herzke a,⇑, Elisabeth Olsson b, Stefan Posner b a b

NILU, Norwegian Institute for Air Research, Hjalmar Johansens gt. 14, 9296 Tromsø, Norway Swerea IVF AB, Argongatan 30, 431 53 Mölndal, Sweden

a r t i c l e

i n f o

Article history: Received 24 October 2011 Received in revised form 10 February 2012 Accepted 7 March 2012 Available online 6 April 2012 Keywords: Human exposure Perfluorinated compounds Consumer products PFOS PFOA Norway

a b s t r a c t Perfluoroalkyl and polyfluoroalkyl substances (PFAS) are used in numerous industrial and consumer products because of their special chemical properties, for instance the ability to repel both water and oil. A broad variety of PFAS have been introduced into the Norwegian market through industrial use (e.g. via fire fighting foams and paints) as well as in treated customer products such as textiles and coated paper. Our present knowledge of the exact chemical PFAS compositions in preparations using perfluorinated compounds is limited. This lack of knowledge means that it is difficult to provide an accurate assessment of human exposure to these compounds or to the amount of waste that may contain treated products. It is a growing concern that these potentially harmful compounds can now be found throughout the global environment. Samples of consumer products and preparations were collected in Norway, with supplemental samples from Sweden. In 27 of the 30 analyzed consumer products and preparations a number of polyfluorinated substances that were analyzed were detected but this does not exclude the occurrence of unknown PFAS. Notable was that perfluorooctanesulphonate (PFOS), which has been strictly regulated in Norway since 2007, was found in amounts close to or exceeding the EU regulatory level in 4 of the 30 analyzed products, all within the leather or carpet product groups. High amounts of fluorotelomer alcohols (FTOHs) were found in waterproofing agents, carpets and textiles, consistent with earlier findings by Fiedler et al. (2010). The presence of PFAS in a broad range of consumer products can give rise to a constant diffuse human exposure that might eventually result in harm to humans. Ó 2012 Elsevier Ltd. All rights reserved.

1. Introduction Perfluoroalkyl and polyfluoroalkyl substances (PFASs) are used in various industrial products, and are occurring in a large range of consumer products. Due to their extraordinary properties (chemically inert, non-wetting, very slippery, nontoxic, non-stick, highly fire resistant, very high temperature ratings, highly weather resistant) they are used for wide variety of applications, e.g. fluoropolymer coated cookware, sports clothing, extreme weather military uniforms, food handling equipment, medical equipment, motor oil additives, fire fighting foams, paints and inks as well as water repellent products (Kissa, 2001; Dinglasan-Panlilio and Mabury, 2006; Sinclair et al., 2007; Fiedler et al., 2010). The manufacture of fluoropolymers often uses PFAS as a production aid or in complex dialkylated or polymeric compounds (Kannan, 2011). Several different types of PFAS are used in consumer products. Among them, mainly chemicals containing poly- and per-fluorinated carbon-chains and a variety of neutral or ionic functional ⇑ Corresponding author. Tel.: +47 777 50 397. E-mail address: [email protected] (D. Herzke). 0045-6535/$ - see front matter Ó 2012 Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.chemosphere.2012.03.035

groups are described in the literature (Dinglasan-Panlilio and Mabury, 2006; Sinclair et al., 2007; Fiedler et al., 2010). In this study we focused on the analyses of prior reported neutral and ionic PFAS as the polyfluorinated fluorotelomer alcohols and sulfonates (FTOHs and FTSs) and perfluorinated carboxylates and sulfonates (PFCAs and PFSs). FTOHs are used to treat paper to improve its moisture and oil barrier properties as well as a waterproofing agent for textiles, particularly for outdoor clothing. In addition, fluorotelomer alcohols are manufactured as a raw material used in the synthesis of fluorotelomer-based surfactants and polymeric products (Dinglasan-Panlilio and Mabury, 2006). The manufacture of FTOHs usually results in a mixture containing six to twelve fluorinated carbon congeners. The FTSs on the other hand are used among other fluorotelomers in fire fighting foam for their film forming properties and the ability to decrease fuel absorption. The quantities of FTSs in the foam are low, but the foam is released directly into the environment (Hagenaars et al., 2011). FTOHs can degrade to fluorotelomer unsaturated acids (FTUCAs) and stable perfluorinated carboxylates (PFCAs) (Dinglasan et al., 2004; Ellis et al., 2004). Besides being a final degradation product, PFCAs belong to the perfluorinated PFAS which have been

D. Herzke et al. / Chemosphere 88 (2012) 980–987

produced intentionally as well, used as a process aid in the manufacture of various fluoropolymers, such as polytetrafluoroethylene (PTFE). Historically, PFCA have been emitted during the manufacture of ammonium perfluorooctanoate (APFO) and ammonium perfluorononanoate (APFN) as well (Prevedouros et al., 2006; Cousins et al., 2011; Kannan, 2011). The manufacture of APFN and APFO leads to a different mixture of PFCAs, with mostly PFNA, PFUnA and PFTRA emitted by APFN production and PFHxA, PFHpA, PFOA and PFNA emitted by the APFO production (Armitage et al., 2009). In the group of perfluorinated sulfonates (PFSs) the perfluorooctanesulfonate (PFOS) has been shown to be present in the environment, wildlife and humans (Giesy and Kannan, 2001; De Silva and Mabury, 2006; Kelly et al., 2009; Butt et al., 2010). As in the case for PFOA, besides the intentional use in products, PFOS and related substances are well known degradation products from precursors that are used commercially for numerous applications. However, the potential toxicity, extreme persistence and accumulation potential of PFOS has resulted in prohibition for new uses or import by chemical regulatory authorities worldwide based on international restrictions by the United Nations Environmental Programme (UNEP) Stockholm Convention, where PFOS has been classified as a persistent organic pollutant (POP) in Annex B. There is scant knowledge of PFAS content in consumer products and as a consequence we know little about possible emissions of PFAS from consumer products (Dinglasan-Panlilio and Mabury, 2006; Sinclair et al., 2007; Kelly et al., 2009; Fiedler et al., 2010; Trier et al., 2011a,b). In general a various number of fluorinated precursors are used to treat the surface of the materials or they are chemically bound to polymers. So far we know little about potential degradation routes to stable PFAS. 3M estimates that 85% of indirect emissions of precursors degrading to stable PFCAs and PFSs are a result of losses from consumer products during use and disposal (e.g. from carpets, clothing, paper and packaging, etc.). The remaining 15% is associated with manufacturing releases from secondary applications (e.g. to carpets) (3M, 2000a; Paul et al., 2009). As emerging application trends increasingly require superior performance characteristics, fluoropolymers will continue to replace other materials in demanding applications that justify their generally higher costs. Human exposure to poly- and per-fluorinated compounds might increase qualitatively and quantitatively, moving from a relatively small group of industrially used PFAS family to a group of very complex and inter-related industrial, environmental and metabolic precursors, or transformation products of one another (Kannan, 2011). International research is ongoing to learn more about sources, fate and pathways of exposure to PFAS, but so far the only regulated group of PFAS substances targets PFOS and its salts, known precursors like PFOSA, N-Me-/-Et-FOSE and FOSA as well as several other identified precursors and intermediates. Some of these substances are listed by OECD, but a full international agreement on regulation, including trace analytical methodologies, is not currently in place for all compounds, thus hampering the regulation and control of PFOS (Haug et al., 2011; OECD, 2007). The REACH regulation does regulate the use of PFOS in aqueous fire fighting foams and textiles (Regulation EC No. 552/2009 and Commission Regulation EU No. 757/2010 concerning POPs), with any PFOS containing foams that were placed on the market before the 27th of December 2006 allowed to be used only until the 27th of June 2011. Additionally the REACH regulation, annex XVII, defines the ban of PFOS if the amount (i) in preparations is equal to or higher than 0.005% of mass, (ii) in semi-finished goods or in parts of such goods is equal to or greater than 0.1% of mass and (iii) for textiles or other coated materials, equal to higher than 1 lg m 2 of the coated material (European Union, 2006). In 2010, the amount PFOS al-

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lowed in preparations or in substances was reduced to equal to or below 10 mg kg 1 (0.001% by weight) in the Commission Regulation (EU) No. 757/2010 (European Union, 2010). Norway follows closely the PFAS regulation of the EU and has banned the use of PFOS in firefighting foams, textiles and impregnation agents (max. content 0.005%) (FOR-2004-06-01-922, 2004). In addition a maximum content of 0.1 mg kg 1 PFOS is allowed in other types of products (FOR-2009-06-22-827, 2009). A similar restriction for PFOA is under development. In order to assess if PFAS treated consumer products are circulating in Norwegian households and are ultimately ending up in the waste disposal and recycling processes, a pilot study investigating potentially PFAS treated products was initiated by the Norwegian Agency for Environment and Climate. The main objective of the study was to investigate so far unscreened for consumer products for the potential to be an additional source of PFAS exposure in Norway and if the threshold amounts for PFOS were followed. No generalizability of the results was aimed at the time of the study rather than a snapshot of the situation to improve the knowledge about the availability of PFAS containing household goods by the average customer in Norway (Herzke et al., 2010). In addition, by analyzing the same brands of impregnation agents acquired in 2006 and 2009, changes of PFAS amounts and pattern were studied in order to assess the effects the ban of certain PFAS compounds on the content in consumer products had had. And finally, we looked further into possible human exposure routes caused by products with elevated PFAS content.

2. Material and methods 2.1. Sample collection Due to the strictly defined frame of the commission by the Norwegian Climate and Pollution Agency, a spot-check sampling of a broad range of consumer products was carried out rather than an in depth sampling campaign. However, the selection of sample types was carried out after a careful review of earlier reports of PFAS in consumer products aiming at a broad variety of product types as possible within the frame of the commission (Berger and Herzke, 2006; SFT, 2006, 2007; Schulze and Norin, 2007; Gewurtz et al., 2009;Washburn et al., 2005; Sinclair et al., 2007; Tittlemier et al., 2007). In this spot-check survey, sample candidates were identified in different ways; (i) by having or giving certain properties that are common for the presence of perfluorinated chemicals (e.g. water repellant, stain resistant, anti-grease, nonstick, surfactant), (ii) by their previous known high concentration of PFAS (Teflon table cloth, AFFF, water proofing agents), (iii) by information from literature that production of these articles may involve fluorinated chemicals (epoxy resin board, semi-conductor fabrication, etc.). A prerequisite for all samples was the direct availability by the customer of private households; the majority of samples were bought in respective stores as a random selection of the most common brands a week before the PFAS determination was carried out in the lab during summer 2009. PCB boards used in big household equipments as washing machines, etc., were received directly from the manufacturer to avoid the costs and labor involved in acquiring the samples of interest from these items. Six different product groups were sampled in Norway and supplementary in Sweden. The product group ‘‘waterproofing agents’’ included different brands of water- and dirt-proofing agents and a lubricant, all from different producers. The product group ‘‘paint’’ included wet-room sealing paint. The sample group ‘‘impregnated products’’ included textiles used for office furniture and table cloth, carpets, food contact paperboard and leather. The group ‘‘electronics’’ included several printed circuit boards (PCBs). We included

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this product group because it is known that PFOS-related substances are still used in a number of applications within the semi-conductor industry and photolithography (Brooke et al., 2004). The group ‘‘fire fighting agents’’ included two powder foams and three aqueous film forming foams (AFFFs). All products were tested as individual samples with the exception of the office furniture textile (n = 8) and leather (n = 4), where individual samples from each sub-group were pooled together before analysis. For non-stick products, a known area of the non-stick layer of the investigated products was removed prior to analyses. Results given for non-stick products refer only to the material removed from these products. To shorten sampling time a number of samples from Sweden were purchased from retailers operating in Norway and Sweden and representing known brands which were available in both countries. Samples like AFFF, waterproofing agents, textiles and paint were all acquired in Norway. See Table 1 for detailed list of samples and abbreviations. From the 30 investigated products were 13 products labeled as containing ‘‘Teflon’’, ‘‘fluorochemicals’’ and ‘‘fluorinated compound’’ and two products were labeled as PFOS/PFOA free and one with ‘‘without PFOS, containing fluoropolymers’’. 2.2. Chemical analysis 2.2.1. Chemicals The target analytes included 21 PFAS (i.e. C4–C14 PFCAs, C4, C6, C8, C10 PFSAs, 6:2 and 8:2 fluorotelomersulfonates (FTSs), and perfluorooctanesulfonamide (PFOSA), 4:2, 6:2, 8:2, 10:2 FTOH). Masslabeled internal standards (ISs) [13C4]–PFOS and [13C4]–perfluorooctanoate (PFOA) as well as [13C4]-6:2 and 8:2 FTOH were applied for analyses of ionic and neutral PFAS and FTOHs respectively in addition to with 3,7-branched perfluorodecanoate (3,7 brPFDcA) and 7:1 FTOH as injection standards (InjSs). All solvents and reagents used in this work were of lichrosolv grade, and were purchased from Merck-Schuchardt (Hohenbrunn, Germany) and all standards were obtained from Wellington laboratories with the exception of 6:2 and 8:2 fluorotelomer-sulfonates and -alcohols which were obtained from ABCR, Germany. 2.2.2. Extraction and analysis Liquid and solid samples were homogenized and extracted based on the extraction method described previously with some minor adjustments mentioned below (Herzke et al., 2009). For heavily contaminated liquid samples like waterproofing fluids and AFFF, an additional dilution step was necessary. Briefly, aliquots of 1 g sample material of a known surface area were spiked with a 13C labeled internal standard mixture containing ionic or neutral compounds respectively. Samples were extracted with methanol for ionic compounds and ethylacetate for FTOHs for three times 10 min in an ultrasonic bath with vortex treatment in between. After centrifugation and solvent evaporation, an aliquot of 1 mL extract was used for dispersive clean up with ENVI-Carb (100 mg, 1 mL, 100–400 mesh, Supelco, USA) and glacial acetic acid in case of ionic PFAS. Finally, a volume of

500 lL was transferred and 2 ng of an injection standard was added and mixed thoroughly. For ionic PFAS, prior to analysis, aliquots of 100 lL were diluted with 2 mM aqueous ammonium acetate solution (NH4OAc, 50/50, v/v). For FTOHs, 1 lL was injected on GC/PCI–MS. The separation and detection of ionic PFAS were performed by liquid chromatography (Agilent1100; Agilent Technologies, Palo Alto, CA and Waters 1525l pump and sample manager 2777, Waters Corporation, Milford, MA) with time-of-flight/quadrupole time of flight high resolution mass spectrometer interfaced with an electrospray ionization source in a negative-ion mode (HPLCESI-(Q)ToF-MS) (LCT/Q-TOF micro, Micromass, Manchester, England) as previously described(Ahrens et al., 2011). Aliquots of 50 lL were injected on an ACE C18 column (150  2.1 mm, 3 lm particle size) (ACT, Aberdeen, UK) using a gradient of 200 lL min 1 methanol and water (both with 2 mM NH4OAc). The initial gradient was set at 50:50 methanol/water, then increased to 85:15 methanol/water (hold for 5 min) and further increase to 99:1 methanol/water (hold for 9 min). Full scan (m/z 165–720) high resolution mass spectra were monitored throughout the chromatograms. Quantification was done using the internal standard method with [13C4]–PFOS and [13C4]–PFOA. FTOHs were analyzed by gas chromatography mass-spectrometry (GC–MS) in selected ion monitoring (SIM)-mode. An Agilent 7890A GC with split/splitless injector coupled to a 5975C MSD (Agilent, Böblingen, Germany) was used with helium carrier gas flow rate of 0.8 mL min 1, and methane as reagent gas in positive chemical ionization (PCI) mode for quantification and in negative chemical ionization (NCI) mode for signal conformation. Injection volume was 1 lL, constant injector temperature was set to 200 °C in splitless mode, the GC temperature program has been previously described (Barber et al., 2007). Transferline temperature was set to 250 °C with the ion source temperature of 250 °C in PCI and 150 °C in NCI. Quantification was done using the internal standard method with 13C 6:2 and 8:2 FTOH.

2.2.3. QA/QC The analytical quality of the laboratory has been approved in interlaboratory studies (van Leeuwen et al., 2009). As standard procedure, laboratory blanks, method detection limits (MDLs) and recoveries were examined. For each sample, a high resolution full scan spectra was used to control positive detections (typical mass tolerance 50 ppm). No laboratory contamination for any of the analyzed compound was detected (n = 5). The recoveries of the IS varied between 64% and 126% in the samples (n = 30).

3. Results and discussion Since liquid and solid products were analyzed, different units were applied (L and kg). When discussing textiles and other items with a regulation relating to a certain amount found on an area of the product (coated fabrics), m2 was used (European Union, 2006, 2010). All results reflect the extractable amounts PFAS.

Table 1 Overview over investigated products (N: Norway; S: Sweden). Product group

Abbreviation

n

Sampling location

Waterproofing agents Paint Coated fabrics (paper, textiles, leather and carpets) Non-stick ware Electrics and electronics Fire fighting agents

WPAs P CFs NSW E and E PF and AFFF

5 3 2+2+2+2 6 3 5

N N N N and S S N

D. Herzke et al. / Chemosphere 88 (2012) 980–987

3.1. PFAS concentrations and composition profiles In all but three samples we found numerous PFAS. PFBA, PFHxS and PFOS belonged to the most detected ionic PFAS (Fig. 1). The detection of shorter chain PFS and PFCA indicates a substitution process within the industrial PFAS application in order to avoid PFOS/A use. The volatile PFAS 6:2, 8:2 and 10:2 FTOH could be detected in more than one third of all products. In all products labeled as ‘‘PFAS containing’’, one or more of the investigated PFAS were detectable. In the three products labeled as ‘‘PFOS/PFOA-free’’ no PFOS or PFOA was found, however, traces of other PFAS were detectable in these samples. 3.1.1. Waterproofing agents and lubricants (WPAs) No PFOS was detected in any of the items of this product group and subsequently no product contained PFOS in higher amounts than permitted in Norway. PFOA was detected in two products with 26 and 208 lg L 1 respectively. However, none of the investigated waterproofing agents/lubricants was free from additional PFAS. Two products contained only minor amounts of short chain PFBA and/or PFBS. The remaining three products contained FTOHs as the major PFAS group (465, 94 and 78 mg L 1 subsequently) and several PFCA congeners. The detected PFCAs could be either explained by precursor degradation or impurities of the FTOHs found, since amounts seem to low to be an intentional ingredient (Table 2). In a recent study, Fiedler et al. reported mainly 8:2 and 10:2 FTOH in nine impregnation agents in concentrations between and
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application. Since these products are of very high viscosity they were weighed rather than measured volumetrically. In one paint no PFAS were detected. The other two wet room sealing paints contained only ionic PFAS at very low levels, with PFOS being the main PFAS with respectively 5.8 and 4.8 lg kg 1. The permitted PFOS contend was not exceeded in the investigated paint samples (0.005% weight). Small amounts of PFHxS could be found in both products as well and some PFBA. It is unknown if the detected PFAS were added intentionally to the products or are impurities caused by production, transport and/or storage. 3.1.3. Paper, textiles, carpets (CF) Both investigated food contact paper samples were free for PFAS. The office furniture textile, (pool of eight samples) and TeflonÒ table cloth were PFOS free. However, several PFCAs could be detected in the table cloth possibly due to the TeflonÒ-treatment of the textile. The TeflonÒ brand is a registered trademark for the fluoropolymer polytetrafluoroethylen (PTFE), commercialized by DuPont. PFOA was used as production aid in the manufacture of PTFE contributing considerably to historically global total PFCA emissions (Prevedouros et al., 2006). The telomeric 6:2, 8:2 and 10:2 FTOHs were detected in both textile samples and comprised more than 90% of the overall PFAS concentrations in these products. The two leather samples had the highest concentrations of ionic PFAS. Office furniture leather (pool of three samples) and black shoe leather showed PFOS levels of 38 and 21 lg m 2, exceeding the EU regulation of 1 lg m 2 (European Union, 2006, 2010). In addition, in the black shoe leather, PFBS and PFHxS were detected too, while only PFBS was detected in the office furniture leather. Stain and water proofing treatment could be the cause of the elevated levels, but natural PFOS content of the leather is a possible source as well. Only small amounts of 8:2 and 10:2 FTOH were found in the office leather, but higher concentrations were found in the shoe leather, again indicating stain and water proofing (Table 2). Of the two analyzed carpets, only one was labeled as TeflonÒ treated, yet PFOS was found in both samples, with levels slightly exceeding the EU regulation of 1 lg m 2 for the TeflonÒ treated carpet (1.04 lg m 2). The same carpet contained 6:2 FTS, PFHxS, and PFHxA, PFHpA and PFOA probably as a result of the TeflonÒ treatment. Both carpets contained 6:2, 8:2 and 10:2 FTOH, with the TeflonÒ treated carpet containing 10 times higher levels than the non-treated carpet. Combined, the FTOHs made up more than 90% of the overall PFAS content of known PFAS in these products. Haug et al. (2011) reported findings of PFAS in dust collected on carpets and sofas in Norwegian households with PFOA (117 lg kg 1) being the dominating PFAS in dust from the furniture, whilst PFBA and PFUnA were mainly detected in dust from carpets. In addition, high amounts of FTOHs (up to 17000 pg m 3) were detected in the air of the rooms where the carpets and sofas were present (Haug et al., 2011).

Fig. 1. Detection frequency of PFAS in the 30 analyzed products (%).

5.90 nd

4.65 nd

nd nd nd nd

nd nd

nd nd nd nd

3.03 nd

nd nd

nd 43.4

nd

nd nd nd 231

2.61 56.0

5.40 126

169

19.1 76.4 220 368

13.7 nd

(C: Carpet; T: Textile, L: Leather, CB: Food Contact Cardboard).

nd nd nd nd

nd 120 721

13 250 330 800 1750 74 250

17 800 nd

nd nd

nd nd 22 425

848 nd nd nd 1610 26 500

nd nd nd nd 10:2 FTOH

6:2 FTOH 8:2 FTOH

nd nd nd nd nd nd

5800

nd nd nd nd 535 54 780

110

17.0 22.0

38.6

nd 13.3

nd nd nd nd nd nd PFTriA PFTeA 4:2 FTOH

nd nd nd

nd nd nd nd nd nd nd nd nd

nd nd nd

nd nd nd

nd nd nd

nd nd nd

nd nd nd

nd nd nd nd nd nd nd 401 nd

nd nd nd

nd nd nd

nd nd nd

nd nd nd

nd nd nd

nd nd nd

nd nd nd

nd nd

nd nd

nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd

nd nd

nd nd nd nd

nd nd nd nd PFUnA PFDoA

nd nd

nd 447

nd nd

nd nd

nd 143

nd nd

nd nd

nd nd

nd nd nd nd 198 1200

nd nd

nd nd

nd nd

nd 0.38

nd nd

nd nd

nd nd

nd nd nd

nd nd nd nd nd nd nd nd nd nd

nd nd

nd nd

nd nd

nd nd

nd nd nd nd

nd nd nd nd

nd 1779 nd nd

nd nd nd nd

nd nd

nd nd nd nd

nd nd

nd nd nd nd

nd nd

nd nd nd 0.40

nd nd 0.42 1.29 nd nd nd nd

nd 3.74 0.51 1.67 nd nd

nd nd nd nd nd nd

6.43 26.2 6.2 nd

nd nd nd nd

nd nd

nd nd nd nd 593 168 nd nd

nd nd nd nd nd 1880

nd nd nd nd PFNA PFDcA

PFHpA PFOA

nd nd nd nd nd nd

nd nd

nd nd nd nd 53.6 208

nd nd

nd nd

nd nd 1.11 PFBA PFPA PFHxA

nd nd nd

404 966 nd nd nd nd 2.93 nd nd

118 nd nd

95 nd nd

75.9 nd 23.0

nd nd nd 81 nd nd 142 nd 25.6 960 1825 3810 27 647 125 000 nd

0.81 nd nd

24.4 nd nd

nd nd nd

nd 3.34 nd

nd nd nd

nd nd nd

nd nd nd

nd nd

60.0 nd

333 nd nd 805 nd nd 17.5 nd nd 605 nd nd 4.68 nd nd 16.3 88.8 nd

nd nd

nd nd nd

nd nd nd

415 nd

11.9 nd 1.86 nd

14.2 nd 213 nd

14.1 nd nd nd

nd nd 24.9 nd

0.80 nd

nd nd

nd nd

nd nd

21.2 nd 38.0 nd nd nd

nd nd

1.04 nd

nd nd 0.08 nd

0.71 nd 0.40 nd 0.03 nd

nd 0.02 nd nd nd nd nd nd

nd nd nd nd

nd nd

nd nd 4.76 nd 5.80 nd

PFHxS PFHpS

PFOS PFDcS

nd nd 0.31 nd 0.53 0.10

nd nd

nd nd

nd nd nd nd nd nd 568 000 114 400

nd nd

nd nd nd nd nd nd 370 000 901 300

0.11 nd

0.06 nd

nd nd

nd nd

nd nd

4.81 nd

nd nd

nd nd

nd nd nd nd 2.84 nd

nd nd nd nd

nd nd nd nd nd nd

nd nd nd nd

nd nd nd nd nd nd

nd nd

nd nd nd

nd nd nd

nd nd

nd 1.36 nd nd 308 nd nd nd nd

nd nd

nd nd nd

nd nd 1.35 nd

nd nd nd

0.65 nd nd

nd nd nd

nd nd

nd nd nd nd nd nd

nd nd nd nd

nd 38.65 nd nd nd nd

199 nd nd nd nd nd nd nd nd PFOSA PFBS PFPS

6:2FTS 8:2FTS

nd nd nd nd nd nd

37 700 nd

nd nd nd nd nd nd nd nd nd nd nd nd 12 300 253 700 nd

nd nd nd nd nd nd 776 600 nd 8400 nd

0.12 nd

0.57 nd

nd nd

nd nd nd

nd nd

nd nd

nd nd

NS6

1000  103 1000  103 1000  103 1000  103 1 1 1 50  103 50  103 50  103 50  103 50  103 PFOS regulated amount (EU, 2006)

50  103

P2 P1

50  103

I5 I4 I3 I2

50  103 50  103 50  103 50  103

1000  103

1000  103

1000  103

1

1

1

1

1

1000  103

1000  103

NS5

kg kg

NS4 NS3

kg kg

NS2 NS1 CB1 L2 L1 T2 T1 C2 C1 E3 I1 AFFF3 AFFF2

L

P3

AFFF

kg

AFFF1

L L

3.1.5. Electronics and electrics (EE) The printed circuit boards where characterized by very low PFAS levels. PFOS (trace amounts) was detected in all three printed circuit boards, with two of the three printed circuit boards containing traces of 6:2 FTS as well.

3.2. Discussion of results with regard to present regulation

kg

kg

3.1.4. Non-stick ware (NSW) Of the six investigated products three pans contained PFOS and PFHxS while PFOA was found in one pan (436 lg kg 1). The same pan contained the highest PFAS concentrations of all the other analyzed ionic PFAS (sum ionicPFAS 739 lg kg 1). A TeflonÒ coating is indicated for this product on the accompanying packaging. The regulated content for PFOS was not exceeded in any of the investigated products (0.1% weight). Traces of 10:2 FTOH were found in one pan and one iron. The iron showed some elevated levels for 6:2 FTOH as well. Begley et al. (2005a,b) detected PFOA residues in non-stick cookware (4–75 lg kg 1) but found no evidence of any of the other PFAS (Begley et al., 2005a,b). Sinclair et al. (2007) detected PFOA and fluorotelomer alcohols (6:2 FTOH and 8:2 FTOH) released from non-stick cookware into the gas phase under normal cooking temperatures, confirming the presence of PFAS in cookware (Sinclair et al., 2007). Since non-stick products are produced worldwide under largely varying conditions and legislation a considerable variability in PFAS content can be expected.

3.1.6. Fire fighting agents Of the five tested firefighting agents, two were powder foams and three AFFFs. The two powder foams contained none of the PFAS analyzed, whereas all three AFFFs contained various PFAS. Two AFFFs contained mainly 6:2 FTS as well as smaller amounts of several PFCAs, but no PFOS was detected. The third AFFF was an old-generation foam containing mostly PFOS and some PFHpS, PFHxS and PFDcS. Due to its high PFOS content, this brand of AFFF belongs to the list of phased out products in Norway and is not available for purchase anymore. The other two AFFF did not exceed the threshold levels for PFOS containing preparations of 0.005% weight. Additionally, high amounts of 6:2, 8:2 and 10:2 FTOHs were found in the old-generation foam as well. Table 2 shows the amounts of detected PFAS in the investigated consumer products and the respective PFOS thresholds set by the EU in 2006. Since the samples were acquired in summer 2009 the EU threshold for preparations adjusted in 2010 to 0.001% weight was not applied (European Union, 2010). For the fire fighting agents only the AFFF products were included.

Paint

L

E1

kg

E2

NSW

kg m2 m2 m2 m2 m2 m2 m2 m2

PCB

L

L WPA

L L

kg

kg

Coated Fabrics

CB2

kg

D. Herzke et al. / Chemosphere 88 (2012) 980–987

lg

Table 2 Average PFAS amounts in six groups of consumer products (WPA: waterproofing agents, AFFF: aqueous fire fighting foams; NSW: non-stick ware; P and I: paints and inks, CF: coated fabrics including food contact paper, E and E: electronic and electric parts).

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With respect to the consumer products analyzed in this study, only a few products exceeded or came close to the regulatory levels for PFOS set by Norwegian legislation. Only the two pooled leather samples (38 and 21.2 lg m 2) exceeded the regulation of 1 lg m 2, whereas the two carpet samples (0.7 and 1.04 lg m 2) were close to the regulatory limit. For all other products tested, PFOS levels were well below the respective regulatory limits. It is recommended to have a continuous follow-up on product groups as water proofing agents, leather and carpets which showed either a high content of volatile PFAS or evidenced PFOS levels close to regulatory thresholds as they might play an important role in human indoor exposure. 3.3. Changes in PFAS content and pattern over time To investigate the changes in production at the time PFOS was banned/phased out in most industrialized countries and 4 years later, we compared the PFAS content in waterproofing agents pur-

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A

B

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sumFTOH from 665 mg L 1 to 80 mg L 1, from 585 to nondetectable and from 4650 mg L 1 to 500 mg L 1 in case A, B and C respectively. In other investigated product groups, such as the TeflonÒ table cloth, similar changes could be observed with a greatly decreased PFCA content and a slightly decreased FTOH content. The most dramatic change was observed in the AFFF product group with a move from mainly PFHxs, PFHpS and PFOS containing products to virtually PFOS-free products which in addition contained only traces of PFCAs (Fig. 3). However, little is known about the global production changes since 2002. 3M was responsible for the vast majority of the supply of PFOS-based substances, producing around 3665 tonnes of PFOSF, the precursor for PFOS-related substances, in 2000 (3M, 2000b). In 2003 this had been reduced to zero following 3M’s decision to stop manufacturing this compound. After 3M voluntarily stopped producing PFOSF in 2002, the production was partly taken over by Asian manufacturers (3M, 2000b; Wang et al., 2010). Two years later, the UK still estimated the use of PFOS in the EU in 2004 to a total of about 500 tonnes year 1, distributed over several different applications (Brooke et al., 2004). Global production of FTOHs was 12  106 kg year 1 in 2006, and sales were at approximately $700 million annually (Wallington et al., 2006). 3.4. Environmental emissions and human exposure

C

Fig. 2. PFAS concentrations in three waterproofing products A, B and C purchased and analyzed in both 2006 and 2009 (lg L 1).

chased and analyzed in 2006 (13 brands) and 2009 (5 brands) (Norin and Schulze, 2007) The analyses of all products in both years were carried out by the same laboratory applying the described methodology, enabling a direct comparison. The average amount of ionic PFAS decreased considerably in 2009 compared with 2006, while the use of PFOS seems to have stopped by 2009 since no PFOS was detected in any of the products sampled in 2009 compared to findings up to 77 lg L 1 in 2006 (Norin and Schulze, 2007). The application of sumFTOHs seems to have decreased considerably as well from on average of 2219 mg L 1 in 2006 to 127 mg L 1 in 2009 but with a similar pattern with a dominating 8:2 FTOH in both years. Of the brands purchased in 2006 and 2009, three brands were identical in both years enabling a direct comparison of any production changes over time (Fig. 2). In brand A, the composition of PFAS was approximately the same in 2006 and 2009 although the overall concentration was reduced. For brand B, the composition of ionic PFAS was changed dramatically moving away from longer chained PFCAs and traces of PFOS to only PFBA and PFBS. Brand C shows a combination of these approaches as the composition of PFAS was reduced to fewer, shorter chained PFCAs and PFOS was removed from the product. For the FTOHs a similar pattern is observable with a strongly reduced contend of

Emissions of PFAS from products can occur during their complete life cycle. Each PFAS group will pose a different emission scenario with regard to its chemical–physical properties, type of application and use as well as amounts in use globally. As can be seen in Fig. 4, water proofing agents (WPAs) and coated fabrics contain mainly volatile PFAS, dominated by 8:2 FTOH. AFFF, non-stick ware and paints are characterized by a mainly ionic PFAS content but with large differences in amounts between the sub-groups. Electronic and electric parts (EE) showed trace amounts of PFAS too low to be applied intentionally. Due to the direct application in the environment when extinguishing fires, PFAS in AFFFs will be emitted either uncontrolled to surface water, soil and sediment or controlled, in the case of subsequent collection of the used foam and water followed by transfer to a waste water treatment plant. Later emissions cannot be excluded since the capability of waste water treatment plants to remove PFAS from the waters might be low (Busch et al., 2010; Huset et al., 2011). PFAS in textiles and other coated fabrics can be released during cleaning or through wear. RIKZ (2002) refers to 3M as providing a worst case estimate of 95% loss of PFOS from carpets over their working life (RIKZ, 2002). Emissions during life time can be released to air, water and soil depending on the chemical–physical properties of the PFAS in question. Washburn et al. (2005) identified carpet-care solution treated carpeting and treated upholstery as containing the most perfluorooctanoate of the fluorotelomercontaining consumer products investigated (Washburn et al., 2005). The amount remaining on the carpet at the end of the lifetime is assumed to be disposed of with the carpet, to landfill or to incineration (Brooke et al., 2004). Trudel et al. applied 0.1, 7 and 23 ng cm 2 PFOA and 0.1, 1.3 and 73 ng cm 2 PFOS for a low-, intermediate- and high-exposure calculation for mill-treated carpet (Begley et al., 2005a,b; Washburn et al., 2005; Trudel et al., 2008). In this study we detected 0.17 ng cm 2 PFOA in one carpet and none in the other while we detected 0.07 ng cm 2 PFOS in carpet 1 and 0.1 ng cm 2 in carpet 2. In both cases, a low exposure scenario would be applicable assessing human exposure. Waterproofing agents are partly distributed as sprays which will amplify the emissions of volatile PFAS into the air. However, during their service life further emissions to the water can be

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Fig. 3. PFAS concentrations in old (concentration scale right side) and new generation AFFF (concentration scale left side) (lg L

expected following washing of the treated equipment. PFAS containing paints and inks will mainly release PFAS to the water assuming the paints are water based and later disposed of via landfill or incineration. In general, the treatment of consumer products with PFAS results in an increased durability, leading to longer service life compared to similar non-treated products. This will likely prolong the emission of PFAS to households and possible human and environmental exposure. When such products are finally disposed, waste landfills and incinerators will have to deal with compounds of an enhanced chemical stability which might not get easily degraded and could lead to harmful emissions to water, soil and air (Busch et al., 2010; Huset et al., 2011). Pilot studies under laboratory conditions indicate that no PFOA is formed by the incineration of fluorotelomer-based acrylic polymers at 1000C but besides that no further information about the fate of PFAS in municipal incineration facilities is known to the authors (Buser and Morf, 2009; Yamada et al., 2005). In addition, widespread PFAS emissions may occur through the uncontrolled use of treated products in recycled materials such as recycled paper, plastic material, textiles and unregulated landfills in developing countries. In our study, the source of some of the lower PFAS concentrations detected is not always clear, since breakdown routes of various fluorinated polymers are not known. Impurities, transfer during production, storage, transport or other sources could contribute to the overall PFAS load. However, PFOS levels close to the regulatory level in the analyzed carpets might pose an important exposure path for humans and especially children. More screening is suggested for the carpet, leather and textile group in order to assess the possible indoor exposure. Several recent studies have shown the elevated levels of volatile PFAS in indoor environment affecting humans (3M, 2000b; Vestergren and Cousins, 2009; Harrad et al., 2010; Langer et al., 2010; Shoeib et al., 2011). Even if levels might seem low in some products, the amount of these products used and deposited could lead to a considerable source of emission into the Norwegian ecosystem especially when disposed into the waste water system. Due to the long service life of PFAS treated products (up to 30 years); emissions will occur for a long time after the production of the product, even if legislation

1

).

Fig. 4. Relative distribution of extractable volatile and ionic PFAS in consumer products.

removes some of the PFAS from the market in the future. Ultimately, oceans and soils will act as a final sink for most PFAS making them available for biological uptake in these ecosystems in the future. Finally, new PFAS will inevitably be introduced into the European and global market, and are likely to turn up in Norwegian households eventually. Put into perspective, the overall human exposure due to PFAS treated products might be low in general, but particular subgroups in the population may receive considerably higher doses than the rest. The presence of PFAS in a broad range of consumer products can give rise to a constant diffuse human exposure in the developed parts of the world. Acknowledgments We thank the Norwegian Agency for Pollution and Climate for funding. We thank Sandra Huber for assisting with the LC/MS measurements and Justin Gwynn for helping with the language.

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References 3M, 2000a. POSF Life Cycle Waste Stream Estimates. 3M, 2000b. Speciality Materials Markets Group St. Paul, MN, 2. Phase-out Plan for PFOS-based Products, OPPT-2002-0043. Ahrens, L., Herzke, D., Huber, S., Bustnes, J.O., Bangjord, G., Ebinghaus, R., 2011. Temporal Trends and pattern of polyfluoroalkyl compounds in tawny owl (Strix aluco) eggs from Norway, 1986–2009. Environmental Science & Technology 45, 8090–8097. Armitage, J.M., MacLeod, M., Cousins, I.T., 2009. Comparative assessment of the global fate and transport pathways of long-chain perfluorocarboxylic acids (PFCAs) and perfluorocarboxylates (PFCs) emitted from direct sources. Environmental Science & Technology 43, 5830–5836. Barber, J.L., Berger, U., Chaemfa, C., Huber, S., Jahnke, A., Temme, C., Jones, K.C., 2007. Analysis of per- and polyfluorinated alkyl substances in air samples from northwest Europe. Journal of Environmental Monitoring 9, 530–541. Begley, T., Castle, L., Feigenbaum, A., Franz, R., Hinrichs, K., Lickly, T., Mercea, P., Milana, M., O’Brien, A., Rebre, S., Rijk, R., Piringer, O., 2005a. Evaluation of migration models that might be used in support of regulations for food-contact plastics. Food Additives and Contaminants 22, 73–90. Begley, T.H., White, K., Honigfort, P., Twaroski, M.L., Neches, R., Walker, R.A., 2005b. Perfluorochemicals: potential sources of and migration from food packaging. Food Additives and Contaminants 22, 1023–1031. Berger, U., Herzke, D., 2006. Per- and polyfluorinated alkyl substances (PFAS) extracted from textile samples. Organohalogen Compounds. Brooke, D., Footitt, D., Nwaogu, T., 2004. Environmental Risk Evaluation Report: Perfluorooctane Sulphonate (PFOS). Building Research Establishment Ltd. Risk and Policy Analysts Ltd. ii Ó Environment Agency, UK. Busch, J., Ahrens, L., Sturm, R., Ebinghaus, R., 2010. Polyfluoroalkyl compounds in landfill leachates. Environmental Pollution 158, 1467–1471. Buser, A., Morf, L., 2009. Substance flow analysis for Switzerland; perfluorinated surfactants perfluorooctanesulfonate (PFOS) and perfluorooctanoic acid (PFOA). 2009 Environmental Studies Nr 0922, 1–144. Federal Office for the Environment FOEN, Bern, Switzerland. Butt, C.M., Berger, U., Bossi, R., Tomy, G.T., 2010. Levels and trends of poly- and perfluorinated compounds in the arctic environment. Science of the Total Environment 408, 2936–2965. Cousins, I.T., Kong, D., Vestergren, R., 2011. Reconciling measurement and modelling studies of the sources and fate of perfluorinated carboxylates. Environmental Chemistry 8, 339–354. De Silva, A.O., Mabury, S.A., 2006. Isomer distribution of perfluorocarboxylates in human blood: potential correlation to source. Environmental Science & Technology 40, 2903–2909. Dinglasan, M.J.A., Ye, Y., Edwards, E.A., Mabury, S.A., 2004. Fluorotelomer alcohol biodegradation yields poly- and perfluorinated acids. Environmental Science & Technology 38, 2857–2864. Dinglasan-Panlilio, M.J.A., Mabury, S.A., 2006. Significant residual fluorinated alcohols present in various fluorinated materials. Environmental Science & Technology 40, 1447–1453. Ellis, D.A., Martin, J.W., De Silva, A.O., Mabury, S.A., Hurley, M.D., Andersen, M.P.S., Wallington, T.J., 2004. Degradation of fluorotelomer alcohols: a likely atmospheric source of perfluorinated carboxylic acids. Environmental Science & Technology 38, 3316–3321. European Union. Directive 2006/122/EC of the European Parliament and of the Council. 20062006/122/EC. European Union, Commission Regulation (EU) No 757/2010. Fiedler, S., Pfister, G., Schramm, K.W., 2010. Poly- and perfluorinated compounds in household consumer product. Toxicological & Environmental Chemistry 92, 1801–1811. FOR-2004-06-01-922, FOR 2004-06-01 nr 922, 2006. Forskrift om begrensning i bruk av helse- og miljøfarlige kjemikalier og andre produkter (produktforskriften), §2-9 and §2-30, Norway. FOR-2009-06-22-827, 2009. Forskrift om endring i forskrift om begrensning av forurensning (forurensningsforskriften), Norway. Gewurtz, S.B., Bhavsar, S.P., Crozier, P.W., Diamond, M.L., Helm, P.A., Marvin, C.H., Reiner, E.J., 2009. Perfluoroalkyl contaminants in window film: indoor/outdoor, urban/rural, and winter/summer contamination and assessment of carpet as a possible source. Environmental Science & Technology 43, 7317–7323. Giesy, J.P., Kannan, K., 2001. Global distribution of perfluorooctane sulfonate in wildlife. Environmental Science & Technology 35, 1339–1342. Hagenaars, A., Meyer, I.J., Herzke, D., Pardo, B.G., Martinez, P., Pabon, M., De Coen, W., Knapen, D., 2011. The search for alternative aqueous film forming foams (AFFF) with a low environmental impact: physiological and transcriptomic effects of two forafac (R) fluorosurfactants in turbot. Aquatic Toxicology 104, 168–176. Harrad, S. et al., 2010. Indoor contamination with hexabromocyclododecanes, polybrominated diphenyl ethers, and perfluoroalkyl compounds: an important exposure pathway for people? Environmental Science & Technology 44, 3221– 3231. Haug, L.S., Huber, S., Becher, G., Thomsen, C., 2011. Characterisation of human exposure pathways to perfluorinated compounds – comparing exposure estimates with biomarkers of exposure. Environment International 37, 687–693. Herzke, D., Posner, S., Olsson, E., 2010. Survey, Screening and Analyses of PFAS in Consumer Products, Report to the Norwegian Climate and Pollution Agency. TA2578/2009. Norwegian Climate and Pollution Agency.

987

Herzke, D., Nygard, T., Berger, U., Huber, S., Rov, N., 2009. Perfluorinated and other persistent halogenated organic compounds in European shag (Phalacrocorax aristotelis) and common eider (Somateria mollissima) from Norway: a suburban to remote pollutant gradient. Science of the Total Environment 408, 340–348. Huset, C.A., Barlaz, M.A., Barofsky, D.F., Field, J.A., 2011. Quantitative determination of fluorochemicals in municipal landfill leachates. Chemosphere 82, 1380–1386. Kannan, K., 2011. Perfluoroalkyl and polyfluoroalkyl substances: current and future perspectives. Environmental Chemistry 8, 333–338. Kelly, B.C., Ikonomou, M.G., Blair, J.D., Surridge, B., Hoover, D., Grace, R., Gobas, F.A.P.C., 2009. Perfluoroalkyl contaminants in an Arctic marine food web: trophic magnification and wildlife exposure. Environmental Science & Technology 43, 4037–4043. Kissa, E., 2001. Fluorinated Surfactants and Repellents. Langer, V., Dreyer, A., Ebinghaus, R., 2010. Polyfluorinated compounds in residential and nonresidential indoor air. Environmental Science & Technology 44, 8075– 8081. Norin, H., Schulze, P.E., 2007. Fluorerade miljögifter i impregneringsmedel. 20077971. Naturskyddsföreningen. OECD, 2007. Lists of PFOS, PFAS, PFOA, PFCA, related compounds and chemicals that may degrade to PFCA. Environment Directorate, Joint Meeting of the Chemicals Committee and the Working Party on Chemicals Pesticides and Biotechnology. 21-8-2007ENV/JM/MONO(2006) 15, revised 2007. Paul, A.G., Jones, K.C., Sweetman, A.J., 2009. A first global production, emission, and environmental inventory for perfluorooctane sulfonate. Environmental Science & Technology 43, 386–392. Prevedouros, K., Cousins, I.T., Buck, R.C., Korzeniowski, S.H., 2006. Sources, fate and transport of perfluorocarboxylates. Environmental Science & Technology 40, 32–44. RIKZ, 2002. Perfluoroalkylated Substances – Aquatic Environmental Assessment. RIKZ and University of Amsterdam. 2002RIKZ/2002.043. Schulze, P.E., Norin, H., 2007. Fluormiljøgifter i allværsjakker. Rapport 2/2006. Norges Naturvernforbund. SFT, 2006. Kartlegging av perfluoralkylstoffer (PFAS) i utvalgte tekstiler. 2006 ISBN 82-7655-285-4. SFT, 2007. Undersøkelse av PFAS-utslipp fra PTFE-belegningsindustri. 2007TA 2233/ 2007; ISBN 978-82-7655-297-3. Shoeib, M., Harner, T., Webster, M., Lee, S.C., 2011. Indoor sources of poly- and perfluorinated compounds (pfcs) in Vancouver, Canada: implications for human exposure. Environmental Science & Technology 45, 7999–8005. Sinclair, E., Kim, S.K., Akinleye, H.B., Kannan, K., 2007. Quantitation of gas-phase perfluoroalkyl surfactants and fluorotelomer alcohols released from nonstick cookware and microwave popcorn bags. Environmental Science & Technology 41, 1180–1185. Stockholm Convention on POPs. The 9 new POPs. In: An Introduction to the Nine Chemicals Added to the Stockholm Convention by the Conference of the Parties at its Fourth Meeting. 10. UNEP (Ref. type: Pamphlet.) Tittlemier, S.A., Pepper, K., Seymour, C., Moisey, J., Bronson, R., Cao, X.L., Dabeka, R.W., 2007. Dietary exposure of canadians to perfluorinated carboxylates and perfluorooctane sulfonate via consumption of meat, fish, fast foods, and food items prepared in their packaging. Journal of Agricultural and Food Chemistry 55, 3203–3210. Trier, X., Granby, K., Christensen, J.H., 2011a. Polyfluorinated surfactants (PFS) in paper and board coatings for food packaging. Environmental Science and Pollution Research 18, 1108–1120. Trier, X., Nielsen, N.J., Christensen, J.H., 2011b. Structural isomers of polyfluorinated di- and tri-alkylated phosphate ester surfactants present in industrial blends and in microwave popcorn bags. Environmental Science and Pollution Research 18, 1422–1432. Trudel, D., Horowitz, L., Wormuth, M., Scheringer, M., Cousins, I.T., Hungerbuhler, K., 2008. Estimating consumer exposure to PFOS and PFOA. Risk Analysis 28, 251– 269. van Leeuwen, S.P.J., Swart, C.P., van der Veen, I., de Boer, J., 2009. Significant improvements in the analysis of perfluorinated compounds in water and fish: results from an interlaboratory method evaluation study. Journal of Chromatography A 1216, 401–409. Vestergren, R., Cousins, I.T., 2009. Tracking the pathways of human exposure to perfluorocarboxylates. Environmental Science & Technology 43, 5565–5575. Wallington, T.J., Hurley, M.D., Xia, J., Wuebbles, D.J., Sillman, S., Ito, A., Penner, J.E., Ellis, D.A., Martin, J., Mabury, S.A., Nielsen, O.J., Andersen, M.P.S., 2006. Formation of C7F15COOH (PFOA) and other perfluorocarboxylic acids during the atmospheric oxidation of 8: 2 fluorotelomer alcohol. Environmental Science & Technology 40, 924–930. Wang, Y.W., Fu, J.J., Wang, T., Liang, Y., Pan, Y.Y., Cai, Y.Q., Jiang, G.B., 2010. Distribution of perfluorooctane sulfonate and other perfluorochemicals in the ambient environment around a manufacturing facility in China. Environmental Science & Technology 44, 8062–8067. Washburn, S.T., Bingman, T.S., Braithwaite, S.K., Buck, R.C., Buxton, L.W., Clewell, H.J., Haroun, L.A., Kester, J.E., Rickard, R.W., Shipp, A.M., 2005. Exposure assessment and risk characterization for perfluorooctanoate in selected consumer articles. Environmental Science & Technology 39, 3904–3910. Yamada, T., Taylor, P.H., Buck, R.C., Kaiser, M.A., Giraud, R.J., 2005. Thermal degradation of fluorotelomer treated articles and related materials. Chemosphere 61, 974–984.