Supplementary Information

Declining trends of polychlorinated dibenzo-p-dioxins, dibenzofurans and non-ortho PCBs

in Canadian Arctic seabirds

Birgit M. Braune and Mark L. Mallory

Canada

HudsonBay

Prince Leopold Island

Fig. S1. Location of Prince Leopold Island in Lancaster Sound, Nunavut, Canada.

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Table S1. Mean arithmetic annual concentrations (pg g-1 wet wt ± standard error) of polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), non-ortho PCBs (nPCBs)

and toxic equivalents (TEQs) as well as 15N (‰ ± standard error) in eggs of thick-billed murres (Uria lomvia) from Prince Leopold Island, Nunavut, Canada.

Year 1975 1987 1988 1993 1998 2003 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014

n (# pools)a 10 (2) 10 (2) 10 (2) 15 (3) 15 (3) 15 (3) 15 (3) 15 (3) 15 (3) 15 (3) 15 (3) 15 (3) 15 (3) 15 (3) 15 (3) 15 (3)

15Nb 14.9 ± 0.07

15.8 ± 0.20

15.5 ± 0.39

14.9 ± 0.07

15.5 ± 0.10

15.5 ± 0.09

15.1 ± 0.20

15.6 ± 0.43

15.9 ± 0.16

16.0 ± 0.16

15.9 ± 0.21

15.7 ± 0.19

15.3 ± 0.14

16.0 ± 0.10

15.6 ± 0.11

15.6 ± 0.38

% lipid 14.9 ± 0.19

11.5 ± 0.47

11.3 ± 0.85

11.8 ± 0.11

12.6 ± 0.25

12.9 ± 0.33

11.3 ± 0.19

10.2 ± 1.42

11.3 ± 0.52

12.8 ± 1.58

12.7 ± 0.38

13.3 ± 0.20

11.8 ± 0.15

11.6 ± 0.22

11.2 ± 0.15

13.8 ± 1.29

PCDDs

2,3,7,8-TCDD 3.36 ± 0.08

2.55 ± 0.35

2.37 ± 0.21

1.33 ± 0.19

1.19 ± 0.09

0.84 ± 0.04

1.00 ± 0.19

0.55 ± 0.30

0.61 ± 0.09

0.86 ± 0.10

0.87 ± 0.10

0.86 ± 0.05

0.79 ± 0.06

0.55 ± 0.01

0.63 ± 0.07

0.57 ± 0.006

1,2,3,7,8-PnCDD 3.72 ± 0.25

3.22 ± 0.90

2.55 ± 0.43

3.03 ± 0.18

2.14 ± 0.50

1.55 ± 0.09

1.34 ± 0.17

0.69 ± 0.36

0.62 ± 0.13

1.56 ± 0.24

1.28 ± 0.08

1.17 ± 0.24

0.92 ± 0.06

0.97 ± 0.10

0.93 ± 0.09

0.74 ± 0.09

1,2,3,4,7,8-HxCDD <0.20c 0.54 ± 0.54

0.52 ± 0.07

0.61 ± 0.61

0.70 ± 0.20

0.43 ± 0.03

0.24 ± 0.13

0.47 ± 0.33 <0.16 0.25 ±

0.250.26 ± 0.03

0.29 ± 0.06

0.16 ± 0.08

0.27 ± 0.01

0.21 ± 0.12 <0.23

1,2,3,6,7,8-HxCDD 2.21 ± 0.94

1.27 ± 1.27

1.41 ± 0.29

2.47 ± 0.38

1.17 ± 0.29

1.13 ± 0.06

0.77 ± 0.09 <0.41 0.50 ±

0.061.03 ± 0.36

0.75 ± 0.13

0.60 ± 0.17

0.59 ± 0.06

0.53 ± 0.08

0.44 ± 0.08

0.58 ± 0.13

1,2,3,7,8,9-HxCDD <0.28 <0.48 0.28 ± 0.02

0.38 ± 0.21

0.31 ± 0.08

0.25 ± 0.02

0.14 ± 0.08 <0.50 <0.17 <0.73 0.14 ±

0.02 <0.24 <0.19 0.19 ± 0.03 <0.12 0.14 ±

0.07

1,2,3,4,6,7,8-HpCDD <0.45 <0.40 0.43 ± 0.008

0.68 ± 0.48

0.46 ± 0.04

0.31 ± 0.01

0.33 ± 0.16 <0.50 0.20 ±

0.100.25 ± 0.25

0.42 ± 0.13

0.44 ± 0.03

0.32 ± 0.07

0.40 ± 0.04

0.35 ± 0.04

0.44 ± 0.23

OCDD 0.72 ± 0.72

0.51 ± 0.20

0.50 ± 0.18

0.77 ± 0.77

0.49 ± 0.13

0.24 ± 0.05

0.51 ± 0.51

0.78 ± 0.25

0.60 ± 0.14 <3.19 0.65 ±

0.040.66 ± 0.17

0.68 ± 0.07

0.89 ± 0.13

1.17 ± 0.18

1.13 ± 0.18

PCDD 10.0 ± 1.83

8.29 ± 2.65

8.05 ± 0.42

9.28 ± 2.08

6.47 ± 0.89

4.76 ± 0.25

4.31 ± 1.10

2.73 ± 0.96

2.53 ± 0.49

4.17 ± 1.39

4.37 ± 0.47

4.04 ± 0.31

3.49 ± 0.24

3.80 ± 0.16

3.82 ± 0.55

3.68 ± 0.46

PCDFs

2,3,7,8-TCDF 2.16 ± 0.22

1.66 ± 0.03

2.57 ± 0.71

2.13 ± 0.17

1.53 ± 0.10

1.56 ± 0.16

0.86 ± 0.04 <0.20 1.01 ±

0.0021.34 ± 0.23

1.02 ± 0.09

1.37 ± 0.18

1.32 ± 0.14

0.78 ± 0.01

1.19 ± 0.04

1.25 ± 0.25

1,2,3,7,8-PnCDF 0.84 ± 0.02

0.67 ± 0.01

0.95 ± 0.09

1.25 ± 0.09

0.40 ± 0.07

0.61 ± 0.05

0.41 ± 0.03

0.27 ± 0.05

0.29 ± 0.08

0.61 ± 0.09

0.38 ± 0.05

0.64 ± 0.03

0.40 ± 0.04

0.45 ± 0.03

0.38 ± 0.02

0.30 ± 0.15

2,3,4,7,8-PnCDF 10.7 ± 2.03

10.8 ± 3.29

8.25 ± 1.20

12.8 ± 1.91

7.14 ± 1.28

7.18 ± 0.21

4.91 ± 0.04

4.42 ± 0.77

2.89 ± 0.38

6.98 ± 1.43

5.19 ± 0.41

4.91 ± 1.06

4.35 ± 0.29

3.48 ± 0.23

3.03 ± 0.11

3.43 ± 0.33

1,2,3,4,7,8-HxCDF 1.61 ± 1.23 ± 0.91 ± 1.86 ± 0.88 ± 0.62 ± 0.48 ± 0.57 ± 0.36 ± 0.97 ± 0.41 ± 0.63 ± 0.45 ± 0.47 ± 0.47 ± 0.48 ± 2

0.69 0.38 0.10 0.27 0.10 0.003 0.10 0.08 0.03 0.44 0.03 0.05 0.04 0.003 0.02 0.04

1,2,3,6,7,8-HxCDF 1.13 ± 0.51

0.95 ± 0.37

0.85 ± 0.19

1.31 ± 0.12

0.62 ± 0.09

0.71 ± 0.02

0.46 ± 0.09

0.47 ± 0.08

0.35 ± 0.04

0.76 ± 0.23

0.48 ± 0.05

0.43 ± 0.05

0.44 ± 0.08

0.43 ± 0.02

0.27 ± 0.02

0.43 ± 0.04

1,2,3,7,8,9-HxCDF 0.36 ± 0.36 <0.30 <0.10 0.38 ±

0.38 <0.20 <0.10 <0.35 <0.26 0.20 ± 0.02 <1.18 <0.03 <0.25 <0.29 0.19 ±

0.04 <0.21 <0.29

2,3,4,6,7,8-HxCDF 1.29 ± 0.66

0.95 ± 0.43

0.83 ± 0.19

1.69 ± 0.18

0.68 ± 0.15

0.79 ± 0.008

0.59 ± 0.007

0.39 ± 0.007

0.62 ± 0.05

0.53 ± 0.42

0.42 ± 0.05

0.51 ± 0.10

0.35 ± 0.05

0.43 ± 0.03

0.27 ± 0.04

0.36 ± 0.03

1,2,3,4,6,7,8-HpCDF 0.26 ± 0.26 <0.35 0.20 ±

0.03 <0.33 <0.20 0.14 ± 0.009

0.21 ± 0.11

0.10 ± 0.07

0.21 ± 0.01 <0.38 0.09 ±

0.0060.63 ± 0.07

0.30 ± 0.02

0.16 ± 0.02

0.35 ± 0.04

0.36 ± 0.05

1,2,3,4,7,8,9-HpCDF 0.33 ± 0.33 <0.35 0.12 ±

0.12 <0.33 <0.20 <0.10 <0.26 <0.18 0.13 ± 0.07 <0.86 <0.02 0.37 ±

0.04 <0.25 <0.18 <0.27 <0.49

OCDF 0.75 ± 0.75 <0.45 0.37 ±

0.200.78 ± 0.78

0.31 ± 0.15

0.17 ± 0.04

0.47 ± 0.28

0.43 ± 0.22

0.42 ± 0.04 <1.58 <0.03 1.32 ±

0.140.52 ± 0.05

0.52 ± 0.08

1.00 ± 0.06

0.42 ± 0.22

PCDF 19.4 ± 5.36

16.5 ± 4.70

15.1 ± 0.44

22.3 ± 1.70

11.9 ± 1.89

11.8 ± 0.19

8.42 ± 0.20

6.76 ± 0.87

6.47 ± 0.66

11.2 ± 2.68

8.03 ± 0.60

10.9 ± 1.39

8.13 ± 0.40

7.05 ± 0.22

6.94 ± 0.13

7.02 ± 0.26

Non-ortho PCBs

PCB-77 250 ± 7.59

140 ± 7.81

176 ± 32.5

120 ± 9.55

79.7 ± 3.17

76.4 ± 6.15

58.4 ± 5.86

63.9 ± 5.79

47.8 ± 5.61

67.8 ± 4.02

49.2 ± 6.18

78.1 ± 4.13

44.3 ± 2.16

40.8 ± 3.76

44.8 ± 4.98

41.6 ± 7.74

PCB126 323 ± 19.3

204 ± 36.3

186 ± 7.50

123 ± 18.3

112 ± 10.6

90.9 ± 3.48

79.1 ± 6.81

82.6 ± 6.92

45.5 ± 5.75

78.1 ± 9.47

76.7 ± 7.04

80.7 ± 9.66

60.6 ± 1.17

53.5 ± 5.41

57.0 ± 3.33

60.1 ± 1.37

PCB-169 74.1 ± 3.67

76.6 ± 16.1

69.5 ± 0.10

59.4 ± 7.63

56.3 ± 6.94

50.3 ± 2.87

54.9 ± 4.99

54.6 ± 6.70

30.5 ± 3.34

52.6 ± 4.79

50.3 ± 3.91

63.5 ± 7.85

43.2 ± 1.74

44.1 ± 2.88

48.3 ± 1.95

46.7 ± 2.83

nPCB 647 ± 15.3

421 ± 44.6

431 ± 39.9

303 ± 34.9

248 ± 20.2

218 ± 10.2

192 ± 17.6

201 ± 0.80

124 ± 14.1

199 ± 14.3

176 ± 15.2

222 ± 18.5

148 ± 1.40

138 ± 11.9

150 ± 9.84

148 ± 9.63

TEQsd

PCDD-TEQ 7.09 ± 0.18

5.81 ± 1.29

4.98 ± 0.23

4.46 ± 0.30

3.41 ± 0.52

2.45 ± 0.12

2.37 ± 0.35

1.27 ± 0.67

1.24 ± 0.22

2.47 ± 0.37

2.18 ± 0.18

2.05 ± 0.29

1.73 ± 0.04

1.56 ± 0.08

1.59 ± 0.17

1.33 ± 0.07

PCDF-TEQ 13.4 ± 2.04

12.8 ± 3.37

11.2 ± 0.51

15.6 ± 1.70

8.94 ± 1.24

9.01 ± 0.16

5.96 ± 0.02

4.63 ± 0.77

4.08 ± 0.40

8.61 ± 1.68

6.38 ± 0.48

6.51 ± 1.15

5.84 ± 0.35

4.47 ± 0.24

4.36 ± 0.09

4.83 ± 0.10

nPCB-TEQ 44.8 ± 1.55

27.5 ± 3.26

27.4 ± 2.37

18.4 ± 2.28

15.2 ± 1.20

13.0 ± 0.53

10.9 ± 0.98

11.5 ± 0.57

6.97 ± 0.82

11.3 ± 1.05

10.2 ± 0.94

12.0 ± 1.04

8.32 ± 0.07

7.43 ± 0.73

7.99 ± 0.55

8.13 ± 0.52

TEQ 65.3 ± 3.77

46.1 ± 7.92

43.6 ± 1.63

38.4 ± 4.12

27.6 ± 2.85

24.4 ± 0.76

19.2 ± 1.30

17.4 ± 0.98

12.3 ± 1.40

22.3 ± 3.05

18.7 ± 1.52

20.6 ± 2.45

15.9 ± 0.39

13.5 ± 1.04

13.9 ± 0.76

14.3 ± 0.47

a Samples were analyzed for PCDDs, PCDFs and nPCBs in pools of 5 eggs. The number of eggs (n) is given with the number of egg pools shown in brackets.

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b Samples collected from 2006-2014 were individually analyzed for 15N, so those data were averaged for groups of the same five eggs that were pooled for the PBDE analyses. Eggs of thick-billed murres from 1975-2003 were analyzed for 15N in pools of three eggs and, therefore, those values were calculated to match the five-egg pools analyzed for PCDDs, PCDFs and nPCBs by proportional weighting of the 15N values (e.g. ([(3 x 15Npool1) + (2 x 15Npool2)]/5; [15Npool2 + (3 x 15Npool3) + 15Npool4]/5; [(2 x 15Npool4) + (3 x 15Npool5)]/5).

c Measurements less than the method detection limit (MDL) are shown as “< MDL” where the MDL value indicated was the highest MDL value for that analyte for that species in that year. If the annual mean included both values > MDL and values < MDL (assigned a value of zero for calculation of the mean) and the calculated mean was less than the highest MDL value for that analyte for that species in that year, then “< MDL” was given.

d TEQ values calculated using World Health Organization avian toxic equivalency factors (TEFs) for PCDDs, PCDFs, and non-ortho PCBs (Van den Berg et al., 1998).

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Table S2. Mean arithmetic annual concentrations (pg g-1 wet wt ± standard error) of polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), non-ortho PCBs (nPCBs)

and toxic equivalents (TEQs) as well as 15N (‰ ± standard error) in eggs of northern fulmars (Fulmarus glacialis) from Prince Leopold Island, Nunavut, Canada.

Year 1975 1987 1993 1998 2003 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014

n (# pools)a 15 (3) 5 (1) 15 (3) 15 (3) 15 (3) 15 (3) 15 (3) 15 (3) 15 (3) 15 (3) 15 (3) 15 (3) 15 (3) 15 (3) 15 (3)

15Nb 13.4 ± 0.09

13.3 13.0 ± 0.07

13.5 ± 0.08

13.5 ± 0.07

12.9 ± 0.05

12.9 ± 0.14

13.2 ± 0.01

13.4 ± 0.01

13.3 ± 0.04

12.7 ± 0.04

12.9 ± 0.12

13.5 ± 0.09

13.4 ± 0.04

13.8 ± 0.09

% lipid 12.7 ± 0.41

11.4 11.9 ± 1.19

11.2 ± 0.21

10.5 ± 0.33

9.08 ± 0.55

9.28 ± 0.45

10.5 ± 1.09

11.5 ± 0.47

11.4 ± 0.13

11.2 ± 0.29

9.83 ± 0.14

10.4 ± 0.22

10.0 ± 0.34

11.3 ± 0.35

PCDDs

2,3,7,8-TCDD 2.23 ± 0.23

1.08 1.29 ± 0.06

0.82 ± 0.06

0.50 ± 0.04

0.48 ± 0.02

0.48 ± 0.08

0.51 ± 0.06

0.54 ± 0.09

0.46 ± 0.05

0.49 ± 0.03

0.70 ± 0.06

0.42 ± 0.06

0.31 ± 0.03

0.52 ± 0.11

1,2,3,7,8-PnCDD 11.5 ± 1.37

6.26 8.22 ± 0.67

4.47 ± 0.25

2.50 ± 0.07

2.47 ± 0.03

1.92 ± 0.21

1.68 ± 0.60

1.63 ± 0.07

2.06 ± 0.16

1.61 ± 0.13

2.84 ± 0.15

1.97 ± 0.32

1.65 ± 0.13

2.00 ± 0.21

1,2,3,4,7,8-HxCDD 2.52 ± 0.83

1.08 2.30 ± 0.38

1.17 ± 0.20

0.75 ± 0.03

0.66 ± 0.03

0.51 ± 0.02

0.43 ± 0.24

0.51 ± 0.25

0.63 ± 0.10

0.56 ± 0.14

0.70 ± 0.11

0.63 ± 0.07

0.57 ± 0.08

0.32 ± 0.20

1,2,3,6,7,8-HxCDD 13.8 ± 1.30

7.00 9.20 ± 1.05

4.36 ± 0.36

2.87 ± 0.11

2.40 ± 0.13

2.33 ± 0.54

1.85 ± 0.69

1.48 ± 0.08

2.05 ± 0.17

1.36 ± 0.09

3.24 ± 0.28

1.87 ± 0.15

1.36 ± 0.15

2.28 ± 0.08

1,2,3,7,8,9-HxCDD 2.19 ± 0.29

1.32 1.76 ± 0.10

0.80 ± 0.13

0.43 ± 0.02

0.26 ± 0.08

0.43 ± 0.15

0.34 ± 0.17 <0.94c 0.42 ±

0.04 <0.32 0.47 ± 0.05

0.47 ± 0.01 <0.33 0.55 ±

0.09

1,2,3,4,6,7,8-HpCDD 2.93 ± 0.21

1.86 1.57 ± 0.25

1.01 ± 0.06

0.45 ± 0.04

0.84 ± 0.15

0.26 ± 0.13

0.51 ± 0.12 <1.12 0.56 ±

0.070.71 ± 0.03

0.70 ± 0.11

0.66 ± 0.04

0.54 ± 0.01

0.35 ± 0.18

OCDD 5.87 ± 1.89

5.42 0.80 ± 0.39

0.51 ± 0.07

0.14 ± 0.03

0.33 ± 0.02

0.49 ± 0.04

0.79 ± 0.11 <2.58 0.47 ±

0.040.58 ± 0.18

0.84 ± 0.08

0.85 ± 0.06

1.04 ± 0.11

1.55 ± 0.49

PCDD 41.1 ± 3.95

24.0 25.1 ± 2.09

13.1 ± 1.04

7.64 ± 0.25

7.44 ± 0.20

6.41 ± 1.06

6.11 ± 1.73

4.53 ± 0.52

6.65 ± 0.50

5.45 ± 0.55

9.49 ± 0.59

6.86 ± 0.63

5.54 ± 0.30

7.57 ± 0.75

PCDFs

2,3,7,8-TCDF 0.75 ± 0.13

0.60 0.59 ± 0.07

0.49 ± 0.04

0.37 ± 0.02

0.29 ± 0.008

0.08 ± 0.02

0.48 ± 0.27

0.41 ± 0.02

0.35 ± 0.03

0.30 ± 0.03

0.50 ± 0.12

0.47 ± 0.06

0.43 ± 0.04

0.38 ± 0.23

1,2,3,7,8-PnCDF 0.55 ± 0.10

0.54 0.47 ± 0.12

0.36 ± 0.06

0.24 ± 0.01

0.23 ± 0.03

0.20 ± 0.02

0.17 ± 0.09

0.34 ± 0.17

0.25 ± 0.04

0.34 ± 0.06

0.27 ± 0.03

0.35 ± 0.03

0.32 ± 0.06 <0.31

2,3,4,7,8-PnCDF 48.5 ± 6.25

28.8 31.7 ± 3.46

20.1 ± 0.48

12.3 ± 0.13

10.2 ± 0.84

9.00 ± 0.45

8.57 ± 2.80

6.76 ± 0.23

10.3 ± 0.78

7.95 ± 0.24

14.4 ± 0.70

9.87 ± 1.18

7.56 ± 0.51

9.16 ± 0.53

1,2,3,4,7,8-HxCDF 6.53 ± 6.94 4.23 ± 2.52 ± 1.15 ± 1.12 ± 0.93 ± 0.86 ± 1.55 ± 0.93 ± 1.03 ± 1.47 ± 0.97 ± 0.96 ± 0.99 ± 5

0.84 0.40 0.28 0.06 0.01 0.10 0.27 0.32 0.06 0.04 0.29 0.11 0.07 0.20

1,2,3,6,7,8-HxCDF 6.57 ± 0.89

4.96 4.77 ± 0.40

2.77 ± 0.35

1.40 ± 0.03

1.29 ± 0.05

1.09 ± 0.08

1.01 ± 0.36

0.91 ± 0.06

1.09 ± 0.11

0.99 ± 0.04

1.73 ± 0.18

1.15 ± 0.06

0.84 ± 0.06

1.29 ± 0.10

1,2,3,7,8,9-HxCDF 0.20 ± 0.20

0.42 <0.25 0.18 ± 0.09 <0.14 <0.15 <0.18 <0.18 <0.64 0.04 ±

0.01 <0.31 <0.45 <0.16 <0.24 <0.52

2,3,4,6,7,8-HxCDF 5.29 ± 0.62

5.10 4.25 ± 0.42

2.60 ± 0.32

1.43 ± 0.09

1.19 ± 0.10

0.72 ± 0.36

1.98 ± 0.66

0.83 ± 0.03

0.99 ± 0.04

1.01 ± 0.07

1.70 ± 0.22

1.10 ± 0.08

0.80 ± 0.11

1.19 ± 0.03

1,2,3,4,6,7,8-HpCDF 1.06 ± 0.15

0.96 0.64 ± 0.15

0.47 ± 0.03

0.19 ± 0.01 <0.31 0.19 ±

0.040.29 ± 0.07 <0.35 0.16 ±

0.020.81 ± 0.14

0.38 ± 0.10

0.20 ± 0.08

0.43 ± 0.07

0.21 ± 0.11

1,2,3,4,7,8,9-HpCDF <0.17 0.26 0.24 ± 0.24 <0.35 <0.10 <0.35 <0.13 0.22 ±

0.04 <0.54 <0.03 0.42 ± 0.07 <0.27 <0.15 <0.20 <0.44

OCDF 0.74 ± 0.28

2.82 0.75 ± 0.39

0.47 ± 0.05 <0.10 <0.50 <0.19 0.49 ±

0.07 <2.77 <0.03 1.47 ± 0.20

0.42 ± 0.21

0.34 ± 0.04

0.98 ± 0.05

0.78 ± 0.18

PCDF 70.4 ± 7.92

51.4 47.8 ± 4.03

30.0 ± 1.59

17.1 ± 0.35

14.4 ± 0.90

12.2 ± 0.91

14.1 ± 3.86

11.0 ± 0.44

14.2 ± 1.05

14.3 ± 0.58

20.9 ± 1.69

14.6 ± 1.51

12.3 ± 0.80

14.2 ± 0.78

Non-ortho PCBs

PCB-77 52.2 ± 11.0

30.9 23.4 ± 3.21

23.7 ± 2.67

20.2 ± 0.93

16.1 ± 1.21

16.3 ± 1.01

12.2 ± 0.73

9.76 ± 0.54

14.9 ± 1.72

9.17 ± 0.39

12.9 ± 0.84

12.0 ± 0.83

10.9 ± 0.56

11.1 ± 1.67

PCB126 467 ± 115

267 287 ± 34.6

165 ± 10.4

110 ± 5.51

96.8 ± 3.31

90.1 ± 0.61

92.1 ± 6.94

52.4 ± 3.52

84.7 ± 4.72

65.9 ± 1.54

103 ± 9.74

78.1 ± 7.56

59.3 ± 4.79

79.8 ± 1.77

PCB-169 181 ± 45.3

131 168 ± 20.0

96.8 ± 1.50

79.5 ± 2.68

84.1 ± 1.75

77.1 ± 12.2

75.4 ± 5.41

38.1 ± 4.26

63.7 ± 2.64

59.1 ± 2.04

80.6 ± 7.32

58.3 ± 5.45

59.4 ± 3.78

69.1 ± 2.69

nPCB 699 ± 170

429 479 ± 57.0

285 ± 13.7

210 ± 8.43

197 ± 4.86

183 ± 13.7

180 ± 12.1

100 ± 7.99

163 ± 8.13

134 ± 3.81

196 ± 17.2

148 ± 12.1

130 ± 9.04

160 ± 3.02

TEQsd

PCDD-TEQ 14.2 ± 1.67

7.60 9.89 ± 0.75

5.47 ± 0.33

3.11 ± 0.10

3.04 ± 0.05

2.49 ± 0.25

2.26 ± 0.58

2.21 ± 0.05

2.61 ± 0.20

2.15 ± 0.18

3.66 ± 0.22

2.48 ± 0.34

2.01 ± 0.17

2.61 ± 0.28

PCDF-TEQ 51.2 ± 6.49

31.2 33.7 ± 3.62

21.4 ± 0.60

13.1 ± 0.17

10.9 ± 0.84

9.38 ± 0.50

9.46 ± 2.68

7.54 ± 0.22

11.0 ± 0.83

8.59 ± 0.26

15.5 ± 0.88

10.7 ± 1.20

8.28 ± 0.52

9.90 ± 0.66

nPCB-TEQ 49.4 ± 12.0

28.4 30.1 ± 3.61

17.8 ± 1.14

12.1 ± 0.58

10.6 ± 0.33

9.90 ± 0.12

9.90 ± 0.73

5.77 ± 0.37

9.28 ± 0.55

7.10 ± 0.17

11.0 ± 0.99

8.47 ± 0.72

6.53 ± 0.51

8.60 ± 0.25

TEQ 115 ± 18.1

67.3 73.6 ± 7.97

44.7 ± 1.72

28.3 ± 0.81

24.5 ± 1.18

21.8 ± 0.63

21.6 ± 3.86

15.5 ± 0.64

22.9 ± 1.58

17.8 ± 0.61

30.1 ± 2.05

21.7 ± 2.25

16.8 ± 1.10

21.1 ± 0.68

a Samples were analyzed for PCDDs, PCDFs and nPCBs in pools of 5 eggs. The number of eggs (n) is given with the number of egg pools shown in brackets.6

b Samples collected from 2006-2014 were individually analyzed for 15N, so those data were averaged for groups of the same five eggs that were pooled for the PBDE analyses. Eggs of northern fulmars from 1975-2003 were analyzed for 15N in pools of three eggs and, therefore, those values were calculated to match the five-egg pools analyzed for PCDDs, PCDFs and nPCBs by proportional weighting of the 15N values (e.g. ([(3 x 15Npool1) + (2 x 15Npool2)]/5; [15Npool2 + (3 x 15Npool3) + 15Npool4]/5; [(2 x 15Npool4) + (3 x 15Npool5)]/5).

c Measurements less than the method detection limit (MDL) are shown as “< MDL” where the MDL value indicated was the highest MDL value for that analyte for that species in that year. If the annual mean included both values > MDL and values < MDL (assigned a value of zero for calculation of the mean) and the calculated mean was less than the highest MDL value for that analyte for that species in that year, then “< MDL” was given.

d TEQ values calculated using World Health Organization avian toxic equivalency factors (TEFs) for PCDDs, PCDFs, and non-ortho PCBs (Van den Berg et al., 1998).

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Table S3. Akaike’s Information Criterion (ΔAICc, corrected for small sample sizes) values for

representative models explaining variation in ln-transformed PCDD, PCDF, nPCB and Total

TEQ concentrations in 45 thick-billed murre egg pools from birds breeding at Prince Leopold

Island, Nunavut, 1975-2014. Models described trends in contaminant concentrations using

multiple regressions developed from potential explanatory variables of year, δ15N and % lipid in

the sample; model weights are presented (wic) as is the R2 from each regression. Only models with

good support (ΔAICc ≤ 2), or the top three models are presented.

Contaminant Model RSS K ΔAICc wic R2

PCDD Year 6.63878 3 0.00 0.59 0.41

Year, % lipid 6.63121 4 2.36 0.18 0.40

Year, δ15N 6.63377 4 2.38 0.18 0.40

PCDF Year, δ15N 2.95362 4 0.00 0.41 0.58

Year 3.15007 3 0.48 0.32 0.56

Year, δ15N, % lipid 2.91559 5 1.96 0.15 0.58

nPCB Year 1.46102 3 0.00 0.44 0.82

Year, % lipid 1.40160 4 0.55 0.33 0.82

Year, δ15N 1.46101 4 2.41 0.13 0.81

Total TEQ Year 1.68735 3 0.00 0.42 0.82

Year, % lipid 1.61246 4 0.37 0.37 0.83

Year, δ15N 1.68293 4 2.30 0.13 0.83

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Table S4. Akaike’s Information Criterion (ΔAICc, corrected for small sample sizes) values for

representative models explaining variation in ln-transformed PCDD, PCDF and nPCB

concentrations in 43 northern fulmar egg pools from birds breeding at Prince Leopold Island,

Nunavut, 1975-2014. Models described trends in contaminant concentrations using linear

regressions developed from potential explanatory variables of year, δ15N and % lipid in the

sample; model weights are presented (wic) as is the R2 from each regression. Only models with

good support (ΔAICc ≤ 2), or the top three models are presented.

Contaminant Model RSS K ΔAICc wic R2

PCDD Year, % lipid 4.14606 4 0.00 0.45 0.75

Year 4.46873 3 0.79 0.31 0.74

Year, δ15N, % lipid 4.13940 5 2.50 0.13 0.75

PCDF Year, % lipid 2.95976 4 0.00 0.69 0.78

Year, δ15N, % lipid 2.95488 5 2.50 0.20 0.77

Year 3.44597 3 4.10 0.09 0.75

nPCB Year 2.56112 3 0.00 0.59 0.77

Year, δ15N 2.55357 3 2.31 0.18 0.76

Year, % lipid 2.56112 4 2.44 0.17 0.76

Total TEQ Year, % lipid 2.48200 4 0.00 0.39 0.82

Year 2.63100 3 0.07 0.38 0.81

Year, δ15N 2.62820 4 2.46 0.12 0.81

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Table S5. Results of backward stepwise regression analyses, with year, % lipid and 15N as

regressors, for concentrations of major congeners in eggs of thick-billed murres and northern

fulmars from Prince Leopold Island, Nunavut, 1975-2014. Adjusted R2 values (R2adj), degrees of

freedom (df) and F-values are presented. p<0.001 in all cases.

Murre Fulmar

R2adj df F R2

adj df F

2,3,7,8-TCDD 0.83 1,43 217.6 0.75 1,41 127.9

1,2,3,7,8-PnCDD 0.74 1,43 127.2 0.84 1,41 217.5

1,2,3,6,7,8-HxCDD 0.44 1,4

3 35.36 0.84 1,41 223.8

2,3,4,7,8-PnCDF 0.55 1.43 55.78 0.83 1,41 211.6

PCB-77 0.83 1,43 213.5 0.79 1,41 157.1

PCB-126 0.84 1,43 234.7 0.81 1,41 179.0

PCB-169 0.36 1,43 26.02 0.58 1,41 57.88

PCDD-TEQ 0.83 1,43 214.2 0.77 1,41 145.3

PCDF-TEQ 0.58 1,43 61.96 0.74 1,41 121.9

nPCB-TEQ 0.89 2,42 170.5 0.81 1,41 185.3

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References

Van den Berg, M., Birnbaum, L., Bosveld, A.T.C., Brunström, Cook, P., Feeley, M. et al. 1998.

Toxic equivalency factors (TEFs) for PCBs, PCDDs, PCDFs for humans and wildlife.

Environ. Hlth. Perspect. 106: 775-792.

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