Supporting Information. Organophosphate Esters in Canadian Arctic Air: Occurrence, Levels and Trends

Transcription

1 Supporting Information Organophosphate Esters in Canadian Arctic Air: Occurrence, Levels and Trends Roxana Sühring 1+, Miriam L. Diamond 1, Martin Scheringer 2,3, Fiona Wong 4, Monika Pućko 5, Gary Stern 5, Hayley Hung 4, Alexis Burt 5, Philip Fellin 6, Henrik Li 6, Liisa M. Jantunen* 7,1 1 Department of Earth Sciences, University of Toronto, 22 Russell Street, Toronto, Ontario, Canada M5S 3B1 2 RECETOX, Masaryk University, Brno, Czech Republic 3 ETH Zürich, 8093 Zürich, Switzerland 4 Air Quality Processes Research Section, Environment and Climate Change Canada, Toronto, Ontario, Canada, M5H 5T4 5 Centre for Earth Observation Science, University of Manitoba, 586 Wallace Building, Winnipeg, Manitoba, Canada R3T 2N2 6 AirZOne, Mississauga, Ontario, Canada, L4Z 1X1 7 Air Quality Processes Research Section, Environment and Climate Change Canada, Egbert, Ontario, Canada L0L 1N0 + Current Address: Centre for Environment, Fisheries and Aquaculture Science (Cefas), Lowestoft, Suffolk NR33 0HT, United Kingdom * Corresponding Author: Liisa M. Jantunen, Air Quality Processes Research Section, Environment and Climate Change Canada, Egbert, Ontario, Canada, L0L 1N0 liisa.jantunen@canada.ca The Supporting Information includes: Details on target compounds, methods, quality control and results per compound and sampling sites. S1

2 Fourteen organophosphate esters (OPEs) were measured in the filter fraction of 117 active air samples from yearly ship-based sampling campaigns ( ), and two land-based stations in the Canadian Arctic, to assess trends and long-range transport potential of OPEs. Four OPEs were detected in up to 97% of the samples, 7 in 50% or less of the samples, and 3 were not detected. Median concentrations of ΣOPEs were 237 and 50 pg m -3 for ship- and land-based samples, respectively. Median concentrations ranged from below detection to 119 pg m 3 for Ethanol, 2-chloro-, phosphate (3:1) (TCEP). High concentrations of up to 2340 pg m 3 were observed for Tri-n-butyl phosphate (TnBP) at a land-based sampling location in Resolute Bay from 2012, whereas it was only detected in one ship-based sample at a lower level. Concentrations of halogenated OPEs seemed to be driven by river discharge from the Nelson and Churchill Rivers (Manitoba) and Churchill River and Lake Melville (Newfoundland and Labrador). In contrast, non-halogenated OPE concentrations appeared to have diffuse or local sources close to the land-based sampling stations. Triphenyl phosphate (TPhP) showed an apparent temporal trend with a doubling-time of 11 months (p = 0.044). The results emphasize the increasing relevance of halogenated and non-halogenated OPEs as contaminants in the Arctic. S2

3 Figure S1: Sampling stations (top) and cruise tracks (bottom); each red dot indicates the start location for the collection of a high-volume air sample (Base map (top) from Schlitzer 2015). S3

4 Table S1: IUPAC name, abbreviation and CAS number of the analysed OPEs (Bergman et al., 2012). Abbreviation Chemical name CAS TCEP Ethanol, 2-chloro-, phosphate (3:1) TCIPP Tris(2-chloroisopropyl)phosphate TDCPP Tris(2,3-dichloropropyl) phosphate EHDPP 2-Ethylhexyl diphenyl phosphate TBEP Tris(2-butoxyethyl) phosphate ToCP Tris-ortho-(cresyl) phosphate TmCP Tris-meta-(cresyl) phosphate TpCP Tris-para-(cresyl) phosphate TDMPP Tris(3,5-dimethyl phenyl) phosphate TEHP Tris(2-ethylhexyl) phosphate TnBP Tri n butyl phosphate TPhP Triphenyl phosphate TPPP Tris(2-isopropyl phenyl) phosphate TTBPP Tris(4-tert-butylphenyl) phosphate S1 Instrumental Analysis All analyses were performed by gas chromatography with mass-selective detector operating in electron impact (GC-EI-MS) and electron-capture negative ion modes (GC-ECNI-MS) using an Agilent 6890 GC or 5975 Mass Selective Detector (MSD). Quantitative analysis was done on a DB-5 column (J&W, Agilent Technologies, 30 m, 0.25 mm i.d., 0.25 µm film thickness). A typical temperature program was: initial temperature 90 o C, hold for 1.0 min, 10 o C min 1 to 160 o C, 2.0 o C min 1 to 230 o C; hold for 5.0 min, 20 o C min 1 to 310 o C; hold for 5.0 min. Samples were injected splitless (2 µl, split opened after 2.0 min). Other instrument conditions were: the helium carrier gas at 40 cm s -1, injector temperature 200 o C, transfer line temperature 250 o C, ion source 230 o C and quadrupole 150 o C. In ECNI mode, the mass spectrometer was operated with methane at 2.2 ml min -1 and ion source at 150 o C. The peak was considered pure if the target/qualifying ion ratio was within 20% of standards. 100 ng of Mirex were added to extracts prior to injection as the internal standard. Random samples were checked for native Mirex/dechlorane and found negative. S4

5 Table S2a: Surrogate ions monitored and recovery rates [%] in Electron Impact Mode. Compound Ions monitored % Recovery Air d 27 -TBP d 21 -TPrP d 12 -TCEP C 18 -TPhP C 2 -TBEP d 5 -Atrazine d 10 -Diazinon C 12 -PCB C 12 -PCB C 12 -PCB S2 QA/QC Sampling media, procedural and field blanks were collected at every step in the sampling processes. Field blanks were collected by installing the GFF in the sampling head, attaching the head to the pump and drawing air for 30 sec. Random GFFs were extracted and analyzed before the samples were sent into the field. Lab blanks consisted of a baked GFF processed in the same manner as the samples. Additional solvent and processing blanks were also done. Samples were field-blank corrected. For a compound to be positive, the sample must exceed the limit of detection (LOD), defined as the LOD = mean blank + 3*SD of the blank. Where there were no peaks in the blanks, the instrumental detection limits (IDLs) were used. Blank values for all compounds ranged from below detection to 3359 pg/sample, since the samples volumes varied, this relates to below detection to 6.7 pg m -3 (based on a 500-m 3 sample) and below detection to 2.2 pg m -3 for a 1500-m 3 sample. S5

6 Table S2b: Surrogate ions monitored and recovery rates [%] in Chemical Ionization Mode, used to assess recoveries of TDCPP. Compound Ions monitored % Recovery Air 13 C 10 -TN d 10 -CPF C 12 -DIEL C 9 -ENDO SUL Table S3: Ions monitored and instrument detection limits (IDL) [pg m 3 ]. Ions Air IDL OPFRs Target/Qualifier 500 m m 3 Mode TCEP 249/ EI TCIPP 99/ EI TDCPP 317/ ECNI EHDPP 251/ EI TBEP 57/ EI TCP (O, M, P) 368/ EI TDMPP 410/ EI TEHP 99/ EI TnBP 99/ EI TPhP 326/ EI TPPP 118/ EI TTBPP 479/ EI MX 272/404 ISTD EI/ECNI S3 Statistical Analysis and Graphical Representation Temporal trends were tested using the PIA statistical application (Bignert 2007). In short, PIA is a robust regression-based analysis to detect trends in time-series datasets (Nicholson et al. 1995) by calculating annual geometric means from the input data and using these as annual index values that are tested for linear trends, as well as non-linear trend components using a 3-year running-mean smoother that is compared with the (log) linear regression. PIA includes an option to control for a third value in the input data as an adjustment variable. This was used to adjust concentration data for temperature (and thereby latitude) using the best-fit (linear) regression relationship between the data values (Bignert 2007). Only data from ship-based sampling campaigns were included for temporal trends because the S6

7 land-based sampling was either just one year (Resolute Bay) or did not consistently include all analytes i.e. the blanks for Alert samples were high due to the composite sample type. Outliers were identified, with outliers defined as data points with a value below Q1 1.5 IQR or above Q IQR, respectively, with Q1 = the first quartile or 25th percentile, Q3 = the third quartile or 75th percentile, and IQR being the interquartile range defined as Q3 Q1. Ocean Data View (version 4.7.4) (Schlitzer 2015) was used for geographic representation of OPE concentrations (Figures 2, 3, S1-S4b), as well as for plotting concentration against temperature and year (Figures S4a,b). For better visibility, data were displayed as gridded field using weighted-average gridding at x-scale length of 15 and x-scale length of 20. All maps obtained this way were compared to non-gridded field representation of the data to ensure no small scale or extreme values were modified or lost as a consequence of the gridding procedure. S4 The Tool Overall Persistence, P OV, and long-range transport potential, LRTP, are key criteria used to assess chemical hazard associated with the distribution of chemicals in the environment. To assist with the evaluation, a consensus multimedia model was developed and made available to the public. This model is the OECD P OV and LRTP Screening Tool, which emerged from an OECD/UNEP Workshop held in Ottawa in 2001 on the Use of Multimedia Models for Estimating P ov and LRTP in the Context of Persistent Bioaccumulative Toxics substances/persistent Organic Pollutants (POPs). This was followed by detailed model comparisons by the expert group from the OECD/UNEP Workshop on Multimedia Models (Fenner et al. 2005). A consensus model arose from these discussions (Wegmann et al. 2009). This model has been freely available since 2006 as a downloadable file from the OECD website ( The model has been used extensively within government agencies tasked with assessing the hazard of chemicals and by research groups (UNEP 2012). Information on input data and the methods used by the Tool has been described in detail in our previous paper (Sühring et al. 2016). In short, data for input parameters (octanol-water partition coefficient, air-water partition coefficient, degradation half-lives in air, water and soil) were extracted from 67 publications ( ). Data points with a value below Q1 1.5 IQR or above Q IQR S7

8 were removed from the input dataset as outliers, with Q1 = the first quartile or 25th percentile, Q3 = the third quartile or 75th percentile, and IQR being the interquartile range defined as Q3 Q1. Table S4: Air Concentrations in the filter fraction of OPEs (Average ± Standard deviation, Overall Median, Median for each of the sampling years , Quebec City (QC)and the St Lawrence River pg m 3 ), temperature (Temp.) [ o C], detection frequencies (Det.)[%], number on analyzed samples (N) and contribution of chlorinated OPEs to total OPEs [%] in the Canadian Arctic, measured in high-volume samples from ship- and land-based sampling from Concentrations below LOD (n.d.) were treated as 0, OPEs that were not analyzed are labelled n.a.. Median concentration [pg m -3 ] Average (without QC) Stdev Overall (without QC) QC, St Lawrence River Det. [%] (N ) Temp. [ o C] TCIPP (92) TCEP (92) TDCPP n.d (117) TPhP n.a. n.d (100) EHDPP n.d. n.d. n.d. n.d. n.a. 8.0 n.a (77) TmCP n.d. 3.7 n.d. n.d. n.a n.a n.d. 24 (67) TEHP n.d. n.d. n.d. n.d. n.a. 3.2 n.a. n.a (51) TnBP n.d. n.d. n.d. n.d. n.a. n.a. n.a. 416 n.d. 15 (52) TpCP n.d. 1.4 n.d. n.d. n.a. n.a. n.a. n.a. n.d. 7 (42) TBEP n.a. n.a. n.d. n.a. n.a. n.a. n.a. n.a. n.a. n.d. n.d (15) TPPP n.a. n.a. n.d. n.d.-1.7 n.d. n.d. n.a. n.a. n.a. n.a. n.d. 2 (42) ToCP n.d. n.d. n.d. n.d. n.d. n.d. n.a. n.d. n.a. n.a. n.d. n.d (64) TDMPP n.d. n.d. n.d. n.d. n.d. n.a. n.a. n.a. n.a. n.a. n.d. n.d (42) TTBPP n.d. n.d. n.d. n.d. n.d. n.d. n.a. n.a. n.a. n.a. n.d. n.d (42) ƩOPEs (117) ƩCl-OPEs (117) Ʃnon-Cl OPEs n.a (117) % Cl-OPEs S8

9 year Table S5: Concentrations [pg m 3 ] of OPEs from ship-based sampling. n.a. indicates not analysed, a 0 signifies values below the limit of detection. For statistical analysis all concentrations below the limit of detection were treated as 0. Long. [ E] Lat. [ N] T [ C] TDCPP TCEP TCIPP TPhP TnBP EHDPP TBEP TEHP TCP1 TCP2 TCP3 TPPP TDMPP TTBPP n.a. n.a. n.a n.a. n.a n.a. n.a. n.a n.a. n.a n.a. n.a. n.a n.a. n.a n.a. n.a. n.a n.a. n.a n.a. n.a. n.a n.a. n.a n.a. n.a. n.a n.a. n.a n.a. n.a. n.a n.a. n.a n.a. n.a. n.a n.a. n.a n.a. n.a. n.a n.a. n.a n.a. n.a. n.a n.a. n.a n.a. n.a. n.a n.a. n.a n.a. n.a. n.a n.a. n.a n.a. n.a. n.a n.a. n.a n.a. n.a. n.a n.a. n.a n.a. n.a. n.a n.a. n.a n.a. n.a. n.a n.a. n.a n.a. n.a. n.a n.a. n.a n.a. n.a. n.a n.a. n.a n.a. n.a. n.a n.a. n.a n.a. n.a. n.a n.a. n.a n.a. n.a. n.a n.a. n.a n.a. n.a. n.a n.a. n.a n.a. n.a. n.a n.a. n.a n.a. n.a. n.a n.a. n.a n.a. n.a. n.a n.a. n.a n.a. n.a. n.a n.a. n.a n.a. n.a. n.a n.a. n.a. S9

10 year Table S5 continued: Concentrations [pg m 3 ] of OPEs from ship-based sampling. n.a. indicates not analysed OPEs, a 0 signifies values below the limit of detection. For statistical analysis all concentrations below the limit of detection were treated as 0. Long. [ E] Lat. [ N] T [ C] TDCPP TCEP TCIPP TPhP TnBP EHDPP TBEP TEHP TCP1 TCP2 TCP3 TPPP TDMPP TTBPP n.a. n.a. n.a n.a. n.a n.a. n.a. n.a n.a. n.a n.a. n.a. n.a n.a. n.a n.a. n.a. n.a n.a. n.a n.a. n.a. n.a n.a. n.a n.a. n.a. n.a n.a. n.a n.a. n.a. n.a n.a. n.a n.a. n.a. n.a n.a. n.a n.a. n.a. n.a n.a. n.a n.a. n.a. n.a n.a. n.a n.a. n.a. n.a n.a. n.a n.a. n.a. n.a n.a. n.a n.a. n.a. n.a n.a. n.a n.a. 8.7 n.a n.a. n.a. n.a. n.a n.a. 8.0 n.a n.a. n.a. n.a. n.a n.a. 4.5 n.a n.a. n.a. n.a. n.a n.a. 0 n.a n.a. n.a. n.a. n.a n.a. 0 n.a n.a. n.a. n.a. n.a n.a. 0 n.a n.a. n.a. n.a. n.a n.a. 0 n.a n.a. n.a. n.a. n.a n.a. 0 n.a n.a. n.a. n.a. n.a n.a. 0 n.a n.a. n.a. n.a. n.a n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. S10

11 year Table S5 continued: Concentrations [pg m 3 ] of OPEs from ship-based sampling. n.a. indicates not analysed OPEs, a 0 signifies values below the limit of detection. For statistical analysis all concentrations below the limit of detection were treated as 0. Long. [ E] Lat. [ N] T [ C] TDCPP TCEP TCIPP TPhP TnBP EHDPP TBEP TEHP TCP1 TCP2 TCP3 TPPP TDMPP TTBPP n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a S11

12 year Table S6: Concentrations [pg m 3 ] of OPEs from land-based sampling. n.a. indicates not analysed OPEs, a 0 signifies values below the limit of detection. For statistical analysis all concentrations below the limit of detection were treated as 0. site Long. [ E] Lat. [ N] T [ C] TDCPP TCEP TCIPP TPhP TnBP EHDPP TBEP TEHP TCP1 TCP2 TCP3 TPPP TDMPP TTBPP 2008 Alert, NT n.a. n.a. n.a. n.a. n.a. n.a. n.a. 0 n.a. n.a. n.a. n.a. n.a Alert, NT n.a. n.a. n.a. n.a. n.a. n.a. n.a. 0 n.a. n.a. n.a. n.a. n.a Alert, NT n.a. n.a. n.a. n.a. n.a. n.a. n.a. 0 n.a. n.a. n.a. n.a. n.a Alert, NT n.a. n.a. n.a. n.a. n.a. n.a. n.a. 0 n.a. n.a. n.a. n.a. n.a Alert, NT n.a. n.a. n.a. n.a. n.a. n.a. n.a. 0 n.a. n.a. n.a. n.a. n.a Alert, NT n.a. n.a. n.a. n.a. n.a. 0 n.a. n.a. n.a. n.a. n.a Alert, NT n.a. n.a. n.a. n.a. n.a. 0 n.a. n.a. n.a. n.a. n.a Alert, NT n.a. n.a. n.a. n.a. n.a. 0 n.a. n.a. n.a. n.a. n.a Alert, NT n.a. n.a. n.a. n.a. n.a. 0 n.a. n.a. n.a. n.a. n.a Alert, NT n.a. n.a. n.a. n.a. n.a. 0 n.a. n.a. n.a. n.a. n.a Alert, NT n.a. n.a. n.a. n.a. n.a. 0 n.a. n.a. n.a. n.a. n.a Alert, NT n.a. n.a. n.a. n.a. n.a. 0 n.a. n.a. n.a. n.a. n.a Alert, NT n.a. n.a. n.a. n.a. n.a. 0 n.a. n.a. n.a. n.a. n.a Resolute Bay n.a. n.a. n.a. n.a. n.a. n.a. n.a Resolute Bay n.a. n.a. n.a. n.a. n.a. n.a. n.a Resolute Bay n.a. n.a. n.a. n.a. n.a. n.a. n.a Resolute Bay n.a. n.a. n.a. n.a. n.a. n.a. n.a Resolute Bay n.a. n.a. n.a. n.a. n.a. n.a. n.a Resolute Bay n.a. n.a. n.a. n.a. n.a. n.a. n.a Resolute Bay n.a. n.a. n.a. n.a. n.a. n.a. n.a Resolute Bay n.a. n.a. n.a. n.a. n.a. n.a. n.a Resolute Bay n.a. n.a. n.a. n.a. n.a. n.a. n.a Resolute Bay n.a. n.a. n.a. n.a. n.a. n.a. n.a Alert, NT n.a. n.a. 1.2 n.a. 0 n.a. n.a. n.a. 0 n.a. n.a. n.a. n.a Alert, NT n.a. n.a. 1.6 n.a. 0 n.a. n.a. n.a. 0 n.a. n.a. n.a. n.a Alert, NT n.a. n.a. 5.8 n.a. 0 n.a. n.a. n.a n.a. n.a. n.a. n.a Alert, NT n.a. n.a. 7.0 n.a. 0 n.a. n.a. n.a. 0 n.a. n.a. n.a. n.a. S12

13 year Table S6 continued: Concentrations [pg m 3 ] of OPEs from land-based sampling. n.a. indicates not analysed OPEs, a 0 signifies values below the limit of detection. For statistical analysis all concentrations below the limit of detection were treated as 0. site Long. [ E] Lat. [ N] T [ C] TDCPP TCEP TCIPP TPhP TnBP EHDPP TBEP TEHP TCP1 TCP2 TCP3 TPPP TDMPP TTBPP 2012 Alert, NT n.a. n.a. 4.3 n.a. 0 n.a. n.a. n.a. 1.7 n.a. n.a. n.a. n.a Alert, NT n.a. n.a. 26 n.a. 1.5 n.a. n.a. n.a n.a. n.a. n.a. n.a Alert, NT n.a. n.a. 8.6 n.a. 0 n.a. n.a. n.a. 0 n.a. n.a. n.a. n.a Alert, NT n.a. n.a. 91 n.a. 2.7 n.a. n.a. n.a. 0 n.a. n.a. n.a. n.a Alert, NT n.a. n.a. 25 n.a. 6.5 n.a. n.a. n.a n.a. n.a. n.a. n.a Alert, NT n.a. n.a. 76 n.a. 4.3 n.a. n.a. n.a n.a. n.a. n.a. n.a Alert, NT n.a. n.a. 20 n.a. 3.9 n.a. n.a. n.a n.a. n.a. n.a. n.a Alert, NT n.a. n.a. 47 n.a. 3.5 n.a. n.a. n.a n.a. n.a. n.a. n.a Alert, NT n.a. n.a. 22 n.a. 3.5 n.a. n.a. n.a n.a. n.a. n.a. n.a Alert, NT n.a. n.a. 18 n.a. 3.0 n.a. n.a. n.a n.a. n.a. n.a. n.a Alert, NT n.a. n.a. 19 n.a. 1.8 n.a. n.a. n.a n.a. n.a. n.a. n.a Alert, NT n.a. n.a. 13 n.a. 1.1 n.a. n.a. n.a n.a. n.a. n.a. n.a Alert, NT n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a Alert, NT n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a Alert, NT n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a Alert, NT n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. S13

14 Figure S2: Spatial distribution of individual Cl-OPE concentrations [pg m 3 ]. (Please note that the scales differ; Maps from Schlitzer 2015). S14

15 Figure S3: Spatial distribution of individual non-cl-ope concentrations [pg m 3 ] (Please note that TnBP is presented on a different scale; Maps from Schlitzer 2015). S15

16 Table S7: Pearson correlation (r) and p value of OPE concentrations [pg m 3 ] and latitude [ N] Pearson r P-value TDCPP -0.63* 5x TCEP -0.43* 3x 10 5 TCIPP -0.34* TPhP EHDPP TBP TBEP TEHP ToCP n.a. n.a. TmCP n.a. n.a. TpCP n.a. n.a. TPPP n.a. n.a. OPE -0.30* Cl-OPE -0.40* non-clope *statistically significant Table S8: Pearson correlation (r) and p value of OPE concentrations [pg m 3 ] and air temperature [ C]. Pearson r P-value TCIPP TDCPP 0.63* 2E-09 TCEP 0.49* 8E-06 TPhP EHDPP 0.38* TmCP TEHP TnBP TpCP TBEP TPPP ToCP n.a. n.a. TDMPP n.a. n.a. TTBPP n.a. n.a. Sum OPE Sum Cl-OPE 0.36* Sum non-cl-ope *statistically significant S16

17 Figure S4a: TPhP concentrations vs temperature (left) and geographic distribution of TPhP in the Canadian Arctic ( ) in pg m 3 (Map and plot from Schlitzer 2015). Figure S4b: TCEP concentrations vs temperature (left) and geographic distribution of TCEP in the Canadian Arctic ( ) in pg m 3 (Map and plot from Schlitzer 2015). S17

18 Figure S5: Temporal trend of TPhP concentrations in the Canadian Arctic ( ) in pg m 3 obtained using the PIA statistical application with temperature/latitude as adjustment variable. References: Bergman, A.; Rydén, A.; Law, R. J.; Boer, J. de; Covaci, A.; Alaee, M.; Birnbaum, L.; Petreas, M.; Rose, M.; Sakai, S.; van den Eede, N.; van der Veen, I. A novel abbreviation standard for organobromine, organochlorine and organophosphorus flame retardants and some characteristics of the chemicals. Environ. Internat. 2012, 49, 57 82; DOI /j.envint Bignert, A. PIA statistical application developed for use by the Arctic Monitoring and Assessment Programme; AMAP, 2007 Fenner, K.; Scheringer, M.; MacLeod, M.; Matthies, M.; McKone, T.; Stroebe, M.; Beyer, A.; Bonnell, M.; Le Gall, A. C.; Klasmeier, J.; Mackay, D.; van de Meent, D.; Pennington, D.; Scharenberg, B.; Suzuki, N.; Wania, F. Comparing estimates of persistence and long-range transport potential among multimedia models. Environ. Sci. Technol. 2005, 39 (7), ; DOI /es048917b. Nicholson, M.D., Fryer, R., Larsen, J.R. A robust method for analysing contaminant trend monitoring data. Techniques in Marine Environmental Sciences ICES Schlitzer, R. Ocean Data View; Alfred Wegner institute, odv.awi.de, Sühring, R.; Wolschke, H.; Diamond, M. L.; Jantunen, L. M.; Scheringer, M. Distribution of organophosphate esters between the gas and particle phase model predictions vs. measured data Environ. Sci. Technol DOI /acs.est.6b UNEP. Stockholm Convention on Persistent Organic Pollutants Report on the assessment of chemical alternatives to endosulfan UNEP/POPS/POPRC.8/INF/28, Wegmann, F.; Cavin, L.; MacLeod, M.; Scheringer, M.; Hungerbühler, K. The OECD software tool for screening chemicals for persistence and long-range transport potential. Environmental Modelling & Software 24 (2), ; DOI /j.envsoft , S18