Onderzoeksrapport naar de kwaliteit van gezuiverd afvalwater van stortplaatsen. Maart Christian Eschauzier en Pim de Voogt

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1 Bepaling van Perfluoroalkylacids (PFAA) in influent en effluent van de waterzuiveringsinstallatie Afvalzorg en in omringend oppervlaktewater van de stortplaats Nauerna. Determination of perfluoroalkyl acids (PFAA) in influents and effluents of the wastewater treatment plant Afvalzorg and in surface waters near the Nauerna landfill Onderzoeksrapport naar de kwaliteit van gezuiverd afvalwater van stortplaatsen Maart 2012 Christian Eschauzier en Pim de Voogt Instituut voor Biodiversiteit en Ecosysteemdynamica 1

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3 Afvalzorg t.a.v. H. Scharff Informatie Christian Eschauzier/ Pim de Voogt / Datum 20 Maart 2012 Geachte Heer Scharff, In november 2011 hebben wij een zestal afvalwater monsters gekregen van Afvalzorg. Het betreft drie influent en drie effluent monsters van niet nader gespecificeerde locaties voor de bepaling van o.a. Perfluoroalkylacids (PFAA) in het kader van een studentenproject in het mastervak Environmental measuring techniques aan de UvA. Daarnaast zijn nog een tiental monsters genomen van de ringsloot en het Noordzeekanaal, de resultaten van deze metingen zijn ook bijgesloten. De extracties, analyses en data checks zijn door de studenten gedaan onder begeleiding en toezicht van mijzelf (Christian Eschauzier). De resultaten van deze analyses zijn vermeld op de volgende bladzijden. Deze resultaten hebben uitsluitend betrekking op de monsters, zoals die door u ter analyse werden aangeboden en de monsters van het omringende oppervlaktewater die zelf genomen zijn. Wij vertrouwen erop u hiermee van dienst te zijn geweest. Met vriendelijke groet, Christian Eschauzier en Pim de Voogt Universiteit van Amsterdam 3

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5 1. Materials and method Analytical method used Samples obtained (November 2011) were stored at 4 C prior extraction and extracted within two weeks after reception. Approximately 150 ml sample was carefully weighed in a methanol pre-washed (three times MeOH and three times with the sample) PP flask. The internal standards (60 ng) (See Table 1 for which internal standards) were subsequently added to the water sample. Solid phase extraction (SPE) cartridges were conditioned by eluting with 4 ml of 0.1% NH 4 OH in methanol and 4 ml of nanopure water, consecutively. Water samples were subsequently filtered over the SPE cartridge via a vacuum extraction manifold, the eluent was discarded and the cartridge was dried under a gentle vacuum air flow. The cartridge was then washed with 2 ml 40/60 vol.% MeOH/H 2 O mixture which was discarded after controlling for two samples that no PFASs were present in the washing solution. The compounds retained on the SPE cartridge were desorbed with 1 ml of 2% NH 4 OH in methanol which was then filtered through an Acrodisc LC 13 GHPPall in a 2 ml PP vial and stored at 4 C prior analysis. The analytical protocol was described in detail before [1]. Briefly, PFAS were analyzed by injecting 20 µl from the extract into a High Performance Liquid Chromatograph (HPLC, Shimadzu, Kyoto, Japan) connected to a tandem mass spectrometer (4000 Q Trap, Applied Biosystems, Toronto, Canada) operating in the negative ionization mode with scheduled MRM. An ACE 3 C column (ID 2.1 mm; length 150 mm, particle size 3 µm, Advanced Chromatography Technologies, Aberdeen, Scotland) was used and the pre-column used for lowering the background of PFAS from the HPLC system was a Pathfinder 300 PS C18 column (ID 4.6 mm; length 50 mm; Shimadzu, Duisburg, Germany), placed before the injection valve. Quality assessment and control All samples were extracted and injected in duplicate. Concentrations reported are the average of both extractions and injections. Quantification of all measurements was performed with a linear twelve-point calibration line (with r 2 > 0.99 for all analytes). Samples were all quantified within the linear dynamic range (0.07 to 140 pg absolute injected) of the calibration line. Analyte concentrations were corrected for total procedural recovery of the mass labeled internal standards. The (method) LOQ is defined as the lowest validated spike level meeting the method performance acceptability criteria (mean recoveries for each representative commodity in the range % for the mass labeled internal standards (and % for the native compounds) and with a RSD 20%) backcalculated to the amount of sample extracted. For some compounds (e.g. PFOA), the lowest achievable limit is determined by the method blank. If that s the case, than the LOQ can be defined as average blank contribution + 10 x standard deviation of at least 3 replicates of the method blank. Calibration levels were used only when complying with the following criterion: (i) The nominal concentration of the different levels and the corresponding concentrations calculated with the linear calibration line (by the HPLC software: Analyst v3.1) of the levels did not deviate more than 30% (arbitrarily chosen), which occurred only in the lower levels. Analytes were identified and quantified using the additional criteria: (ii) Analyte peak area of the sample was higher than that of the lowest calibration level (defined by criterion (i)). (iii) Analyte peak area of the sample was lower than that of the highest calibration level. (iv) The peak area ratio of mass transitions 1 and 2 of the analyte in the sample did not deviate more than ±30% of the average ratio of the same mass transitions determined for the calibration levels. Method used was validated internally and the laboratory participated in interlab-studies where z-scores smaller than plus or minus two were obtained, except for PFOA which was 2.13 PFBA is a known problematic compound and lower recoveries are generally accepted in scientific literature. 5

6 Table 1 Analytes and internal standards used and analyzed. Abbreviation Compounds Quantification by internal standard PFBA Perfluorobutanoic acid 13C4 PFBA PFPA Perfluoropentanoic acid 13C4 PFBA PFHxA Perfluorohexanoic acid 13C2 PFHxA PFHpA Perfluoroheptanoic acid 13C4 PFOA PFOA Perfluorooctanoic acid 13C4 PFOA PFNA Perfluorononanoic acid 13C5 PFNA PFDA Perfluorodecanoic acid 13C2 PFDA PFDoA Perfluorododecanoic acid 13C2 PFDoA PFTrDA Perfluorotridecanoic acid 13C2 PFDoA PFTeDA Perfluorotetradecanoic acid 13C2 PFDoA PFHxD Perfluorohexadecanoic acid 13C2 PFDoA PFOcD Perfluorooctanoic acid 13C2 PFDoA PFBS Perfluorobutane sulfonate 13C4 PFHxS PFHxS Perfluorohexane sulfonate 13C4 PFHxS PFOS Perfluorooctane sulfonate 13C4 PFOS PFDS Perfluorodecane sulfonate 13C4 PFOS 13C4 PFBA Perfluoro[ C] butanoic acid 13C2 PFHxA Perfluoro [1.2-13C] hexanoic acid 13C4 PFOA Perfluoro [ C] octanoic acid 13C5 PFNA Perfluoro [ C] nonanoic acid 13C2 PFDA Perfluoro [1.2-13C] decanoic acid 13C2 PFDoA Perfluoro [1.2-13C] dodecanoic acid 2O 18 PFHxS Perfluoro [1.2O 18 ] octane sulfonate 13C4 PFOS Perfluoro [ C] octane sulfonate 6

7 Locations sampled are given in Figure 1. Figure 1 Locations sampled around the Nauerna landfill area. Recoveries of the mass labeled internal standards are given in tables 2 and 3. Table 2 Recoveries (%) of the mass labeled internal standards and LOQs of the influent and effluent samples. Avg conc blank (ng/l) LOQ (ng/l) Infl. recovery (%) Effl. recovery (%) PFBA <LOQ 3,5 5 8 PFPA <LOQ 3,5 PFHxA <LOQ 3, PFHpA <LOQ 3,5 PFOA <LOQ 3, PFNA <LOQ 0, PFBS <LOQ 0,21 PFHxS <LOQ 0, L PFOS <LOQ 2, Br PFOS 0,66 7

8 Table 3 Recoveries (%) of the mass labeled internal standards and LOQs of the surface water sampled. PFAA Avg conc blank (ng/l) Stdev blank LOQ (ng/l) Average Recovery (%) PFBA <LOQ - 0,04 16 PFPA <LOQ - 0,46 - PFHxA 4,0 0, PFHpA <LOQ - 0,48 - PFOA 0,35 0, PFBS <LOQ - 0,47 - PFHxS <LOQ - 0,03 57 L-PFOS 0,13 0,07 0,85 30 Br-PFOS <LOQ - 0,09-8

9 2. Results The analysis results are shown in Table 4. Table 4 PFAA concentrations (ng/l) present in Influent and effluent wastewater treatment samples. Analyte in ng/l Sample code PFBA PFPA PFHxA PFHpA PFOA PFNA PFBS PFHxS Br-PFOS L-PFOS Sum PFAA INF A INF B INF C EFF A EFF B EFF C

10 Table 5 Concentrations of PFAAs in Nauerna surface water in ng/l (see figure 1 for corresponding locations). Analyte in ng/l Sample PFBA PFPA PFHxA PFHpA PFOA PFNA PFBS PFHxS L-PFOS Br-PFOS ,3 13 3,4 14 0,9 11 4,1 9 4, ,9 10 2,4 10 0,9 10 3,1 7,1 3, ,9 12 2,8 13 0,8 10 3,7 8, ,3 9,6 2,4 9,6 0,9 9,6 3 7,7 3, ,5 8,5 1,5 8 0,3 4,9 2 3,5 2, ,1 9,5 2,3 9,7 0,6 6,1 2,3 5,8 4, ,2 9,7 1,8 8,3 0,4 5,7 1 1,8 2, ,6 10 2,4 12 0,4 9,4 3,3 6,5 4, ,7 12 2,7 11 0,7 10 3, ,4 9,4 2,7 12 0,6 <loq 1,6 2,2 3,2 average 16 2,8 10 2,4 11 0,7 8,6 2,8 6,7 4,4 stdev 3,2 1,2 1,4 0,53 1,9 0,23 2,3 1,0 3,8 1,4 10

11 Conclusions The concentrations encountered in the influents and effluents are comparable to landfill leachate concentrations from different places over the world (e.g. [2]) and the effluents, when discharged, constitute a point source of PFAA to the aquatic environment. Table 4 shows that the wastewater treatment methods used are not sufficient to remove PFAA from the wastewater. It is known that wastewater treatment plant effluents from landfills are point sources of PFAA to the environment. The dilution effect of the North sea canal mitigates the effect on the environment. Concentrations measured in the surface waters and the ring-ditch (Table 5) are low and of similar order of magnitude as the concentrations encountered in the North sea canal in previous studies [3, 4]. No firm conclusions can be drawn regarding the source of the PFAA measured in the surface waters surrounding the landfill. For questions feel free to contact the authors. 8

12 Literature cited 1. Eschauzier, C.; Haftka, J.; Stuyfzand, P. J.; de Voogt, P., Perfluorinated compounds in infiltrated river rhine water and infiltrated rainwater in coastal dunes. Environmental Science and Technology 2010, 44, (19), Busch, J.; Ahrens, L.; Sturm, R.; Ebinghaus, R., Polyfluoroalkyl compounds in landfill leachates. Environmental Pollution 2010, 158, (5), Kwadijk, C. J. A. F.; Korytà r, P.; Koelmans, A. A., Distribution of perfluorinated compounds in aquatic systems in the netherlands. Environmental Science and Technology 2010, 44, (10), Eschauzier, C.; de Voogt, P.; Brauch, H.-J.; Lange, F. T., Polyfluorinated Chemicals in European Surface Waters, Ground- and Drinking Waters. In Polyfluorinated Chemicals and Transformation Products, Knepper, T. P.; Lange, F. T., Eds. Springer Berlin / Heidelberg, 2012; Vol. 17, pp