-SETAC Supplemental Data Archive-
AN INTERLABORATORY COMPARISON STUDY FOR THE DETERMINATION OF DIALKYL
PHTHALATE ESTERS IN ENVIRONMENTAL AND BIOLOGICAL SAMPLES
Michael G. Ikonomou†*, Barry C. Kelly†, Joel D. Blair‡, Frank A.P.C. Gobas‡
†Fisheries and Oceans Canada, Institute of Ocean Sciences, Ocean Sciences Division, 9860 West
Saanich Road, Sidney, BC, Canada, V8L 4B2
‡School of Resource and Environmental Management, Simon Fraser University, 8888 University
Drive, Burnaby, BC, Canada, V5A 1S6
* To whom correspondence may be addressed: Michael.Ikonomou@dfo-mpo.gc.ca
This PDF file includes:
Supplemental Tables S1-S3
Supplemental Figures S1-S3
1
Table S1. Summary of laboratory participation.
DPEs
LAB A
LAB B
LAB C
LAB D
LAB E
Low-level High-level
Calibration Calibration
Solution
Solution
x
x
x
x
x
Marine
Sediment
x
x
x
x
2
Carp-2
CRM
x
x
x
x
Fortified Livestock Municipal
Milk
samples
Sludge
x
x
x
x
x
x
All analytes
DBP, DEHP
All analytes
All analytes
DEHP only
Table S2. Summary of procedural blanks (ng/sample), method detection limits (MDL, ng/g wet wt.) and observed concentrations (ng/g
wet wt.) of dialkyl phthalate in CARP-2 certified reference material reported by Lab A, B, C, and D. Concentrations are reported as
arithmetic means and standard deviations (SD) of three extracted samples (n=3) a. Relative standard deviations (RSD, %) are also shown
for blank corrected concentrations. Values shaded in gray represent measurements below the calculated MDL, determined from observed
residues in all reported procedural blanks (i.e., 3 × SD blanks).
LAB A
Reported concentration (ng/g wet wt.),
uncorrected for blank amounts
(arithmetic mean ± SD)
Overall average blank level (ng/sample)
(arithmetic mean ± SD)
MDL (ng/g wet wt.)
(SD × 3)
% blank contribution to final sample
extract
Reported blank corrected concentration
(ng/g wet wt.)
(arithmetic mean ± SD)
Relative standard deviation (RSD, %)
DMP
DEP
0.82 ±0.03
13.4 ±5.12
0.53±0.17
1.20± 0.11
DIBP
2.48 ±0.22
1.34± 0.27
DBP
BBP
DEHP
DOP
16.41 ±0.62
5.75± 1.09
1560 ±147
25.1 ± 4.46
9.02± 1.93
2.88± 0.42
11.4± 2.37
7.55± 0.17
0.10
0.10
0.20
1.21
0.28
1.99
0.04
36.5%
5.05%
30.6%
31.1%
28.6%
0.4%
17.0%
0.52 ±0.03
8.30 ±5.19
1.27± 0.24
11.2 ±0.40
3.45 ±0.89
1550± 148
24.9 ±447
6.5%
62.5%
19.2%
3.6%
25.7%
9.5%
17.9%
DMP
DEP
-
-
DIBP
-
DBP
< MDL
BBP
-
DEHP
1480 ± 197
DOP
-
LAB B
Reported concentration (ng/g wet wt.),
uncorrected for blank amounts
3
(arithmetic mean ± SD)
Overall average blank level (ng/sample)
(arithmetic mean ± SD)
MDL (ng/g wet wt.)
(SD × 3)
% blank contribution to final sample
extract
Reported blank corrected concentration
(ng/g wet wt.)
(arithmetic mean ± SD)
-
-
-
-
-
-
-
-
868 ± 1413
-
290 ±373
-
-
424
-
112
-
-
100%
-
2%
-
-
< MDL
-
1410±193
-
-
Relative standard deviation (RSD, %)
13.7%
LAB C
Reported concentration (ng/g wet wt.),
uncorrected for blank amounts
(arithmetic mean ± SD)
Overall average blank level (ng/sample)
(arithmetic mean ± SD)
MDL (ng/g wet wt.)
(SD × 3)
% blank contribution to final sample
extract
Reported blank corrected concentration
DMP
DEP
DIBP
DBP
BBP
DEHP
DOP
9.67 ± 0.98
469 ± 29.0
9.35 ± 2.85
140 ± 152
63.6 ± 32.4
1430 ± 186
4.47 ± 1.79
43 ± 14.0
1312 ± 415
13.8 ± 16.5
129 ± 37.1
226 ± 210
383 ± 239
189 ± 249
8.41
250
9.9
22.2
126
144
149
84%
53%
28%
17%
67%
5%
100%
0.95 ± 1.11
273 ± 31.8
9.35 ± 2.85
121 ± 152
41.9 ± 32.6
1380 ± 187
< MDL
4
(ng/g wet wt.)
(arithmetic mean ± SD)
Relative standard deviation (RSD, %)
116%
11.6%
30.2%
126%
77%
13.6%
-
DMP
DEP
DIBP
DBP
BBP
DEHP
DOP
< LODb
40.9 ± 3.0
176 ±2.65
284 ± 9.12
< LOD
6850 ±94.4
< LODb
< LODb
23.5
181
652
< LOD
60.5
< LODb
LODb
7.0
157
533
LOD
55
LODb
20.2%
25.7%
34.9 %
31.0 ± 3.0
94.0 ± 2.65
190 ± 9.17
LAB D
Reported concentration (ng/g wet wt.),
uncorrected for blank amounts
(arithmetic mean ± SD)
Overall average blank level (ng/sample)
(arithmetic mean ± SD)
MDL (ng/g wet wt.)
(SD × 3)
% blank contribution to final sample
extract
Reported blank corrected concentration
(ng/g wet wt.)
(arithmetic mean ± SD)
< LODb
0.2 %
< LODb
9.7%
2.8%
4.8%
Relative standard deviation (RSD, %)
a
Weight of CARP-2 certified reference material extracted by Lab A, B, C and D was 2g, 10g, 5g and 1 g, respectively.
b
LOD = represent limit of detection reported by Lab D was 10 ng/g.
5
6820 ± 94.4
< LODb
1.4%
-
Table S3. Summary of procedural blanks (ng/sample), method detection limits (MDL, ng/g dry wt.) and observed concentrations (ng/g
dry wt.) of dialkyl phthalate in marine sediment reported by Lab A, B, C, and D. Concentrations are reported as arithmetic means and
standard deviations (SD) of three extracted samples (n=3) a. Relative standard deviations (RSD, %) are also shown for blank corrected
concentrations. Values shaded in gray represent measurements below the calculated MDL, determined from observed residues in all
reported procedural blanks (i.e., 3 × SD blanks).
LAB A
Reported concentration (ng/g dry wt.)
uncorrected for blank amounts
(arithmetic mean ± SD)
Overall average blank level (ng/sample)
(arithmetic mean ± SD)
MDL (ng/g dry wt.)
(SD × 3)
% blank contribution to final sample
extract
Reported blank corrected concentration
(ng/g dry wt.)
(arithmetic mean ± SD)
Relative standard deviation (RSD, %)
DMP
DEP
DIBP
DBP
BBP
DEHP
DOP
63.6 ± 16.4
5.21 ± 1.80
14.9 ± 4.77
140.9 ± 40.4
163.7 ±50.3
1970 ±87.9
195 ±34.2
0.53 ± 0.17
1.20± 0.11
1.34± 0.27
9.02± 1.93
2.88± 0.42
11.4 ± 2.37
7.55± 0.17
0.46
0.45
0.87
5.63
1.28
9.20
0.19
1.5 %
42.6%
16.6%
11.9%
3.3%
1.1%
7.2%
13.8 ± 1.72
0.65 ± 0.43
2.63 ± 0.66
26.5 ± 5.76
34.2 ± 5.92
430 ± 46.6
2.36 ± 0.19
12.5%
65.5%
25%
21.7%
17.3%
10.8%
6.0%
DMP
DEP
-
-
DIBP
-
DBP
27.3 ± 4.5
BBP
-
DEHP
1760 ±147
DOP
-
LAB B
Reported concentration (ng/g dry wt.)
uncorrected for blank amounts
6
(arithmetic mean ± SD)
Overall average blank level (ng/sample)
(arithmetic mean ± SD)
MDL (ng/g dry wt.)
(SD × 3)
% blank contribution to final sample
extract
Reported blank corrected concentration
(ng/g dry wt.)
(arithmetic mean ± SD)
-
-
-
-
-
-
-
-
868 ± 1413
-
290 ±373
-
-
1414
-
373
-
-
100%
-
6.2 %
-
-
13.6 ± 2.7
-
1720 ±147
-
20.2%
Relative standard deviation (RSD, %)
8.6%
LAB C
Reported concentration (ng/g dry wt.),
uncorrected for blank amounts
(arithmetic mean ± SD)
Overall average blank level (ng/sample)
(arithmetic mean ± SD)
MDL (ng/g dry wt.)
(SD × 3)
% blank contribution to final sample
extract
Reported blank corrected concentration
(ng/g dry wt.)
DMP
DEP
DIBP
DBP
BBP
DEHP
DOP
155 ± 49
2916 ± 163
111 ± 55.5
634 ± 32.8
600 ± 87
9870 ± 2240
236 ± 11.8
43 ± 14.0
1312 ± 415
13.8 ± 16.5
129 ± 37.1
226 ± 210
383 ± 239
189 ± 249
18.7
555
22.0
49.4
279
319
331
62%
100%
27.4%
45.2%
84%
8.7%
100%
9.3 ± 5.6
< MDL
9.51 ± 11.7
46.5 ± 16.1
< MDL
1340 ± 208
< MDL
7
(arithmetic mean ± SD)
Relative standard deviation (RSD, %)
60.4%
-
123%
34.5%
-
15.5%
-
DMP
DEP
DIBP
DBP
BBP
DEHP
DOP
3.62 ±0.77
16.8 ±0.30
< LODb
194 ±12.2
<LODb
1280 ±28.8
< LODb
< LODb
23.5
< LODb
652.6
< LODb
60.5
< LOD
LODb
14.9
LODb
1135
LODb
119
LODb
-
100%
-
100%
-
2.4 %
-
3.62 ±0.77
2.77 ±0.30
< LODb
102 ±12.2
< LODb
1270 ± 28.8
< LODb
-
2.3%
-
LAB D
Reported concentration (ng/g dry wt.),
uncorrected for blank amounts
(arithmetic mean ± SD)
Overall average blank level (ng/sample)
(arithmetic mean ± SD)
MDL (ng/g dry wt.)
(SD × 3)
% blank contribution to final sample
extract
Reported blank corrected concentration
(ng/g dry wt.)
(arithmetic mean ± SD)
21.2%
10.9%
11.9%
Relative standard deviation (RSD, %)
a
Weight of wet sediment extracted by Lab A, B, C and D was 5g, 2g, 5g and 1 g, respectively.
b
LOD = represent limit of detection reported by Lab D was 10 ng/g.
8
Figure S1 Structural formula of dialkyl phthalate esters.
O
C
C
O
C
O (CH2)nCH3
O
O (CH2)nCH3
C
O
n =0 Dimethyl Phthalate (DMP)
n = 1 Diethyl Phthalate (DEP)
n =3 Di-n-Butyl Phthalate (DnBP)
n =5 Di-n-Octyl Phthalate (DnOP)
R
1
O
R
2
O
R1=C4H9 R2 = CH2C6H5: Butyl Benzyl Phthalate (BBP)
R1= R2 = CH2CH(C2H5)(CH2)3CH3: Bis(2-ethylhexyl) phthalate (DEHP)
R1= R2 = C6H13 isohexyl (C6 isomers)
R1= R2 = C7H15 isoheptyl (C7 isomers)
R1= R2 = C9H19 isononyl (C9 isomers)
R1= R2 = C10H21 isodecyl (C10 isomers)
9
Figure S2. Measured blank levels (ng/sample) of DPEs (sheep milk) and DEHP (sheep muscle
and liver), reported by Lab A and Lab E during interlaboratory study # 2. Data are presented as
arithmetic means  standard deviation on a logarithmic scale.
Lab A
Lab E
Blank Levels
(ng/sample)
10000
1000
100
10
1
DPEs
DEHP
DEHP
(Sheep Milk) (Sheep Muscle) (Sheep Liver)
10
Figure S3. Measured blank levels (ng/sample) reported by Lab A during analyses of municipal
sludge samples for individual DPEs (A) and C6-C10 isomeric mixtures (B).
600
(A) Individual DPEs
DEHP
Blank Level
(ng/sample)
500
BBP
400
DBP
300
DIBP
DEP
200
DMP
100
0
1
2
3
4
5
(B) Isomeric Mixtures
1000
Blank Level
(ng/sample)
C10
C9
800
C7
C6
600
400
200
0
1
2
3
Blank #
11
4
5