9
(J© S CUBED =
A Division of Maxwell laboratories. Inc.
NARRATIVE ON THE DEVELOPMENT
AND VALIDATION OF THE
"CONSOLIDATED GC METHOD FOR THE
DETERMINATION OF ITD/RCRA ANALYTES
USING SELECTIVE GC DETECTORS"
Under SAS 107
SSS-R-86-8072
S-CUBED Reference No.: 32145-01
S-CUBED Document No.: R71
Prepared by
Paul Marsden
Task Manager
Submitted to
William A. Telliard
Industrial Technology Division
USEPA
401 M Street, Southwest
Washington, D.C. 20460
July, 1986
Box 1620, La Jolla, California 92038-1620 3398 Carmel Mountain Road, San Diego, California 92121-1095
Tel: (619) 453 0060 TWX: 910-337-1253 Telecopier: (619) 755-0474
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TABLE OF CONTENTS
Section Page
1.0 INTRODUCTION 1
2.0 CATALOG OF METHODS 2
3.0 DEVELOPMENT OF THE PROCEDURE 4
4.0 METHOD VALIDATION 8
5.0 METHOD DETECTION LIMITS 9
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1.0 INTRODUCTION
Several very similar packed column GC methods have been developed
for the analysis of hazardous chemicals and water. These include
Methods 608, 608.1, and 617 for halogenated organics and Methods 614,
622 and 701 for organophosphates. In order to allow quality
environmental data to be collected in the most cost effective manner,
S-CUBED has developed a consolidated method for the determination of all
of the parameters of Methods 608, 608.1, 614, 617, 622 and 701. This
method requires a single extraction followed by two separate capillary
GC analyses using the electron capture detector (ECD) or the flame
photometric detector (FPD). While it was not possible to develop a
method that could be used to quantitate simultaneously appear
organochlorine, organophosphate, and phenoxyacid herbicides (Method
615), S-CUBED presents an improved and safer procedure for the analysis
of phenoxyacid herbicides than the present Method 615.
The two methods have bee consolidated into a single analytical
scheme that can be used for the quantitative determination of the
ITD/RCRA analytes listed in Tables 1 and 3. A flow scheme for the
analysis of samples is pictures in Figure 1.
1
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2.0 CATALOG OF METHODS
A comparison of Methods 608, 608.1, 614, 615, 617, 622, and 701 is
presented in Table 4. Each of the methods is a water method that
specifies in initial sample size of 800 to 1,000 mL. Adjustment of the
pH of the sample is required in only two of the methods (615 and 617).
The extraction solvents that are required are methylene chloride, 15
percent methylene chloride in hexane, or diethyl ether. Th^ required
volume of extracting solvents is less than 200 mL for each of the
methods. The final volume of the extract used for GC analysis ranges
between 1 and 10 mL. Several GC columns are required at GC oven
temperatures ranging from 100*C to 215*C. The primary column for most
methods is a 1.5 percent SP2250/1.9 percent SP2401 mixed phase column
that was specifically developed for pesticide analysis. Seven other
coatings are required by different methods including SP2401, DC-200, 0V-
1 Ultrabond 20M, OV-210, and QF-1. The QA/QC requirements for all of
the methods are the same. They require that (1) the individual
laboratory demonstrate the precision and accuracy of the method using
standards in the laboratory prior to analyzing samples, (2) the
laboratory demonstrate adequate recovery of the analytes of interest,
and (3) the laboratory spike at least ten percent of the samples to
demonstrate method performance on actual samples. Several cleanup
options are also allowed by these various methods. They include shaking
the sample with mercury to remove sulfur contaminants, and the use of
absorbent columns to remove polar contaminants, (the absorbent generally
specified is Florisil but alumina is specified in the case of Method
701).
The one method that is quite different from all the others
presented in Table 4 is Method 615. It is used for the analysis of
phenoxyacid herbicides and requires three different extractions during
sample preparation. In addition, a base hydrolysis must be done so that
2
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any herbicide esters are converted to the free acids prior to
derivatization. The fact that this method requires partitions between
different acid/base solutions, as well as hydrolysis and derivatization
means that the modified Method 615 was included in the consolidated
pesticide method as a separate procedure.
3
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3.0 DEVELOPMENT OF THE PROCEDURE FOR APOLAR ANALYTES
Each of the 600 series method was published for the analysis of
water samples only. While in actual practice these methods have been
used for a variety of environmental matrices including solids, sludges,
and even tissue, the methods work best for determining analytes in clean
water. It was the purpose of this study to develop a method that could
be used to analyze the full list of parameters in Table 1 from complex
multimedia environmental samples.
3.1 SAMPLE EXTRACTION FOR APOLAR ANALYTES
One liter water samples are required and are adjusted in pH between
5 and 9 using either one-to-one sulfuric acid in water or six normal
sodium hydroxide. Once the pH of the samples has been adjusted the
water is extracted using methylene chloride in a continuous liquid-
liquid extractor for a 18-hour period. The continuous liquid extractor
is specified as the extraction method of choice because it is less prone
to forming emulsions than the separatory funnel extraction and it
provides the most reproducible extraction of the combined parameters
from water.
Soil samples are extracted using an ultrasonic horn (Heat Systems
Ultrasonics or equivalent). Thirty grams of the solid sample is mixed
with 60 g of sodium sulfate and extracted using one-to-one
acetone/methyIene chloride. It is critical that the sodium sulfate
adsorb all of the water in the solid sample since there is a significant
loss in extraction efficiency using the ultrasonic horn when water is
present. It was decided that solid samples should not have the pH
adjusted because such pH changes could cause the evolution of toxic
gases such as H2S or could change the surface chemistry of the solids
and thus affect the extraction efficiency unpredictably.
4
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Selecting the technique for extracting sludge samples is typically
difficult for the analysis laboratory. The proposed combined method
states the most sludges should be diluted with water and extracted with
a continuous liquid-liquid extractor, but does allows the option of
extracting them by sonication after sufficient sodium sulfate is added
to adsorb all water. Since sludges vary greatly in their water content,
it was felt that flexibility in the choice of sample preparation be
allowed. While it may be possible to use total moisture content or
percent suspended solids as more rigid criteria for making this
decision, the time required to perform those procedures does not seem
cost effective and would delay analyses. Organophosphate pesticides
should be extracted as soon as possible after sampling in order to
reduce potential analyte hydrolysis which occurs rapidly for this class
of compounds.
3.2 SAMPLE CLEANUP FOR APOLAR ANALYTES
Because each of the 600 series method was originally developed as a
water method, they do not contain sufficient cleanup steps to ensure
adequate chromatography of complex samples. These deficiencies in
cleanup are addressed in this consolidated method. All solid and sludge
samples must be cleaned up using gel permeation chromatography (GPC) to
remove high molecular weight molecular that degrade chromatographic
columns (GPC is an option for water samples). It is requires that each
sample be cleaned up using adsorption chromatography on Diol cartridges
(supplied by a number of manufacturers including Analytichem, J.T.
Baker, or Supelco) to remove polar interferents that could
co-chromatograph with method parameters and/or cause poor
chromatography. It is felt that both of these cleanup steps are needed
to remove all of the potential interfering compounds that might be
extracted from samples.
5
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3.3 GC ANALYSIS OF APOLAR
In order to achieve analytical separation of the large number of
analytes included in the ITD/RCRA list, it is required that temperature
programmed capillary CC be used. Megabore capillary (ID 0.53 mm) is a
superior alternative to regular (narrow bore) capillary analysis in this
application because (1) megabore capillary columns can be placed into
normal one-quarter inch packed column injector and detector ports with
only a minimal amount of modification, and (2) megabore capillary
columns can handle a larger injection, which means that highly complex
sample extracts are less likely to overload the column. We chose to use
the DB-5 and the SPB-608 megabore columns for this analysis.
The retention time of the apolar parameters of the consolidated
method are given in Tables 1 and 2 (different temperature programs were
used for organochlorine and organophosphates). As can be seen from the
table, these large lists of analytes are resolved very well on each of
the columns with a <40 min run time. Using the megabore capillary
columns, there is only a minimum number of analytes that co-elute.
3.4 MODIFIED HERBICIDE METHOD
Method 61S presents great difficulties in the normal analytical lab
because of its requirement of the use of ethyl ether as an extraction
solvent. S-CUBED replaced Method 615 with a modification of the Method
8150 validated at EMSL-LV. The modified method requires methylene
chloride as an extraction solvent rather than ether and requires the use
of FlorisiI cartridge cleanup of the derivatized phenoxyacid herbicides
prior to GC analysis. We have found that this additional cleanup
greatly improves the chromatography of the derivatized herbicides by
removing the large tail on the solvent peak that is observed whenever
environmental samples have been derivatized using dioazomethane.
6
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Retention times for the derivatized herbicides on the DB-5 and the
SPB-608 columns are reported in Table 8. We found that it was not
possible to combine the neutral organochlorine pesticides with the
derivatized herbicides because it caused too much co-elution of
analytes, for this reason separate GC analysis of the derivatized
herbicides must be performed. The retention times of the derivatized
herbicides will be reported by the end of August.
7
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4.0 METHOD VALIDATION
Validation of the consolidated method is underway. This is being
done by determining the recovery of method parameters spiked into water.
Recovery values for the high concentration organochlorine experiment are
reported in Table 50. The recoveries generally fall between 80JS and
120% except where poor chromatography caused poor quantitative results.
Work is in progress to determine the recovery of the apolar
organochlorine parameters when they are spiked at 5 and 50 ng/L, as well
as the recoveries of the organophosphate and the phenoxyacid parameters.
Work that has been completed at S-CUBED on organophosphates or by LEMSCQ
on the phenoxyacids demonstrate >7056 recovery of these parameters using
this method.
8
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5.0 METHOD DETECTION LIMITS
The method detection limits reported in the protocol are 50 ng/L
for apolar organochlorine pesticides, 500 ng/L for organophosphate
pesticides and 5 ng/L for phenoxyacids. The limits for the apolar
compounds can be reduced by a factor of 10 by passing all of the hexane
extract through the Diol column (Section 4.3.4) prior to GC analysis.
This modification in the protocol results in a detection limit of
<5 ng/L for apolar organochlorines and <50 ng/L for organophosphates.
It has been our experience that this sample concentration is not
required for the samples that we have received thus far on this project.
In fact, samples often require further dilution in order to bring
chromatograms on scale.
9
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TABLE 1 AF'OLAR ORGAIMOCHLDRINE.
PARAMETERS OF THE CONSOLIDATED METHOD
RETENTION TIME
COMPOUND METHOD DB-5 SPB-608
A1 d r i n
608,617
19. 77
18. 33
Aror 1 or 1016
608,617
mu11 i p1e
mult i p1e
Aroclor 1221
608,617
mult i p1e
mul11 pie
Aroclor 1232
608,617
rnult i pie
multi pie
Aroclor 1242
608,617
mult i p1e
multi pie
Aroclor 1248
608,617
multi pie
multi pie
Aroclor 1254
608,617
multi pie
multiple
Aroclor 1260
608,617
multi pie
multi pie
BHC,alpha
608,617
13.77
13. 70
BHC,beta
608,617
14. 74
15. 62
BHC,pamma
608,617
15. 01
15. 22
BHC , del t. a
608,617
15. 93
17. 15
Captan
617
22. 03
24. 24
Carbophent h i on
617,622
28. 44
28. 69
Ch). or dan e
608,617
mu11 i p 1 e
multiple
Chi ] or ob enz y 1 at e
608. 1
26. 49
26. 03
DDL'
608,617
26. 99
27. 10
dde:
60S,6]/
24. 70
24. 16
DD r
6O8,617
29. 01
28. 75
Dial late(cis,trans)
no 1
3.57,13.91
12.89,13.2C
Di chloran
617
14.31
14.80
Dieldrin
608,617
24.88
24.35
Errdosulfan I
608,617
23. 54
22.81
Endosul-fan II
60S,617
26.49
27. 15
Endosulfan sulfate
608,617
28.77
29.71
Endri n
608,617
26.02
26. 11
Endrin Aldehyde
608,617
27. 48
28. 82
E-.ridrin ketone
no
31.25
33. 27
Hep tach1 or
608,617
1 &. 14
16. 87
Heptac.h 1 or epoxide
608,617
21 . 69
21. 01
Hex achlorobenzene
no
14. 24
13. 37
Isodri n
617
2 1.19
20.33
i'n. t boxychl or
617
32. 17
33. 37
I 'ii r ex
no
34. 49
33. 59
Ni trofen
608.1,617
25.99
26. 35
PCNB
617
15. 24
14. 78
Toxaphene
mu1t1p1e
multipie
Ti i f 3. ural i n
12.95
1 1 . 01
RELATED CQI-H
0UNDS
COMPOUND
METHOD
DB-5
SPB-608
Captofol
no
31 . 26
26.83
Chi oroneb
608. 1
10. 46
10.67
Ch]oropropylate
608. 1
nd
nd
DbCP
608. 1
5.91
5.96
Di c. of ol
617
32.35
32.76
t ridazole
608. 1
9'. 82
9. 76
: ¦' F' j j 11 r i e
no
28. 04
26. 28
1 6 • < i i,)| 11i Ethyl an )
nc
•• J*' r
26. 09
: t | ¦ •¦¦¦<(:: !'"i ) ::
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TABLE 2 AF'OLAR QRGANOPHOSPHOROUS
PAR AMI: ILK& OF THE CONSOLIDATED METHOD
RETENTION TIME
COMPOUND METHOD DB-5 SPB-608
A:: i nphos ethyl
Azinphos methyl
Carbophenthi on
Chi or-f envi nphos
Chiorpyrophos
Coumophos
Demeton (mi :-ovinphos
TOCP
Tr ich1 oro f on
Tri. methyl phosphate
no
614,622
617,622
no
622
622
614,622 18
614,622,7
/ '-i
614,622
614,701
621
622
614,701
614,701
614,622,7
622
39. 04
38.34
25.25
33.57
31. 17
39.83
31,20.96
24.27
9.63
15.23
20. 64
39.93
23. 71
37. 80
36. 17
36.43
35. 83
3 1.83
10. 69
38. 47
3-1. 72
14. 18
20. 04
19. 01
31.85
31. 83
19. 94
37. 56
27. 05
20. 1 1
6. 44
22.63
34.65
38.79
11.91
38. 49
38. 04
35. 10
31. 86
26. 88
38. 87
15.90,18. 84
20. 00
7. 91
19. 12
20. 18
33. 17
19. 96
36. 71
34. 79
35. 93
35. 20
29. 45
9. 23
37. 25
28. 78
12.88
20. 11
17.40
27.62
23. 71
17. 52
37. 20
24. 46
18. 02
5. 12
18.81
32. 99
37. 7 1
nd
nd
RELATED
COMPOUNDS
C0MF'l:llK!I>
METHOD
DB-5
SPB--608
t'ol star
622
36. 34
nd
Chiorpyrophos,me
622
nd
nd
Crotox yphos
no
34. 06
33.07
Di c h 1 or -f en t h i on
701
9.63
7.91
Ethopr op
622
18.62
16.48
Merphos
622
nd
26. 82
Me-t hy1 tr i thi on
70 J
nd
nd
Ponne 1
no
29. 23
22. 98
'1 okiit hi on
no
34. 67
n d
1 r i c i i j or or .ale
no
32. 19
rid
Ch
nd =- not determined
ydf'meion methyl no signal, not a method parameter
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TABLE 3 PHENOXYACID
ANALVTES OF CONSOLIDATED METHOD
COMPOUND METHOD DB-5 SPB-608
Dinoseb 615
2,4-D 615
2,4,5-T 615
2,4,5-TP 615
RE I. AT'FD COMPOUNDS
D&I&pon 615
2,4-DB 615
Dicambci 615
Dich]orprop 615
MCPA 615
MCPP 615
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TABLE 4 Consolidation of Methods
Method
Number
608
608.1
617
614
622
701
615
Sample
Volume
1 L
1 L
1 L
1 L
1 L
800-900 mL
1 L
pH Adjust
No
No
6 to 8
No
No
No
pH 2
pH 10
pH 2
Extraction
Solvent
Organochlorlnes
Methylene Chloride
Methylene Chloride
15% CHgClg/Hexane
Organophosphates
15% CI-LCL/Hexane
15% CHgClp/Hexane
15% CHgClg/Hexane
Extraction
Volume (mL)
3x60
3x60
3x60
3x60
3x60
3x25
Phenoxyacld Herbicides
Ethyl Ether 150,50,50
Water 10
Ethyl Ether 20,10,10
Final
Volume (mL)
10
10
10
10
10
1
NA
NA
1
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TABLE 4 Consolidation of Methods
Method
Number Derivative GC Column 1 Temperature GC Column 2 Temperature Detector
608
608.1
617
None 1.5% SP2250/1.95% SP2401 200*C
None 1.5% SP2250/1.95% SP2401 100-215 (iso)
None 1.5% SP2250/1.95% SP2401 200*C
3% OV-1
Ultrabond 20M
3% OV-1
200*C
200*C
200* C
ECD
ECD
ECD
614
622
701
None 1.5% SP2250/1.95% SP2401 200* C
None 5% SP2401 100-215 (prog)
None 5% DC-200 185* C
3% OV-1
3% SP2401
5% QF-1
200* C
170-250 (prog)
185*C
FPD, NPD
FPD, NPD
FPD, NPD
615
Diazomethane 1.5% SP2250/1.95% SP2401
185*C
5% OV-210
185*C
ECD
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TABLE 4 Consolidation of Methods
Method
Number QA/QC Requirements Cleanup Options
608 P&A, Recoveries, spike 10% of Samples
608.1 P&A, Recoveries, spike 10% of Samples
617 P&A, Recoveries, spike 10% of Samples
Hg for S, Florisil
Hg for S, Florisil
Hg for S, Florisil, Hex/aceto/hex ext.
614 P&A, Recoveries, spike 10% of Samples
622 P&A, Recoveries, spike 10% of Samples
701 P&A, Recoveries, spike 10% of Samples
Hg for S, Florisil, Hex/aceto/hex ext.
Allowed if recovery > 85%
5% water deactivated alumina, Florisil
615
P&A, Recoveries, spike 10% of Samples
None specified, allowed if recovery is >85%
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TABLE! 5 RECOVERY OF £3 INGLE COMPONENT
A P O i... A R !-l A i... 0 G E N A T E D F' E S T IC I D E S (5 0 0 n q / L )
L) B b F"' B fa i..> 8
COMPOUND RECOVERY ("/.) rsd RECOVERY ("/.) rsd
A I d r :i. n
13 .C'S n
3. 1
75. 7
10 „ 3
BHC, al pha
1 o b. 9
7. 9
1 OS. 7
5. 4
BMC,beta
94. 2
9. 1
99 „ 9
' 6.5
BHC, g aiiirna
109. 9
3. 8
103. 3
5. 7
BHC,del ta *
30. 4
48
*
27. 0
1 6
Cap tan
n d
n d
C a r b a a h e n t hi :i. o n *
185. 2
8
*
C1'11 orobenzyl ate
1 I. 8 „ 2
12
86.. 5
8. 8
DDD
117.2
8.5
1 13 „ 2
10 „ 6
DDE
82. 1
32
89. 0
''3
DD T
97. 3
18
89. 1
8.9
Dial late
n d
nd
D:i. ch 1 or an
23. 4
26
23. 1
13
D i. e 1 d r i n
93. 7
16
102. 8
9 „ 3
Endosulfan I
81 . 6
16
83. 8
1 3
EndosuIfan II
63. 7
34
74. 4
24
E n d a s u I f a n S 0 4 *
38. 3
*
.1.4. 5
25
Endrin
97. 2
' ? r?
100. 6
16
E n d r i n A1 d e h y d e #
22,. 2
*
Endrin ketone *
1 4. 1
23
*
Heptac:hi or *
59. 1
28
*
60., 4
28
Hept a'c:h 1 or epo>: i de *
468. 3
85. 1
4. 6
l-leac h 1 or ob enzene
n d
nd
I sc;idr :i. n
54. 9
21
59. 2
1 7
ivlethio;-;ychl or
104. 9
12
106 „ 6
3. 9
lvl i r e;-:
9 0. 5
9.8
108. 5
7. :i.
Hitrofen
90, 3
11
115. 0
65
PCNB
97.5
14
93,. 3
:i. 6
T r if1ur al i n
111. 3
5.5
123. 8
29
Values marked with a (*) had coeluti nq peaks
nd = not determined
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