&EPA
United States
Environmental Protection
Agency
Environmental Monitoring
Systems Laboratory
P.O. Box 93478
Las Vegas NV 89193-3478
EPA/600/4-89/049 f
December 1989
c
Research and Development
Evaluation of Sample Extract
Cleanup Using Solid-Phase
Extraction Cartridges
Project Report
-------
EVALUATION OF SAMPLE EXTRACT CLEANUP
USING SOLID-PHASE EXTRACTION CARTRIDGES
by
__ Viorica Lopez-Avila, Janet Benedicto, and June Milanes
(^ Acurex Coiporation
i Environmental Systems Division
^ Mountain View, California 94039
I
Contract Number 68-03-35 1 1
Project Officer
Werner F. Beckert
Quality Assurance Division
Environmental Monitoring Systems Laboratory
Las Vegas, Nevada 89193-3478
ENVIRONMENTAL MONITORING SYSTEMS LABORATORY
OFFICE OF RESEARCH AND DEVELOPMENT
U.S. ENVIRONMENTAL PROTECTION AGENCY
LAS VEGAS, NEVADA 89193-3478
U.S. Environmental Protection Agency
Region 5, Library (PL-12J)
77 West Jackson Boulevard, 12th
Chicago, 1L 60604-3590
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NOTICE
The study presented in this document has been funded wholly or in part by the United
States Environmental Protection Agency under Contract Number 68-03-3511 to Acurex
Corporation. This report has been subjected to the Agency's peer and administrative review,
and it has been approved for publication as an EPA document. Mention of trade names or
commercial products does not constitute endorsement or recommendation for use.
11
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PREFACE
This is the final report for Work Assignment 0-11, EPA Contract No. 68-03-3511,
"Evaluation of Sample Extract Cleanup Using Solid-Phase Extraction Cartridges," conducted at
Acurex Corporation, Project No. 8110. The project was directed by Dr. Viorica Lopez-Avila.
The report was written by Dr. Viorica Lopez-Avila. Technical support for this project
was provided by Ms. Janet Benedicto and Mr. June Milanes.
• »*
111
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ABSTRACT
Fractionation and cleanup of sample extracts prior to instrumental analysis is used to
remove coextracted materials that interfere with the determination of target analytes. Such
fractionations and cleanups are usually accomplished by column chromatography, gel permeation
chromatography, or acid-base partitioning. The purpose of this project was to evaluate the
application of solid-phase extraction cartridges containing Florisil, alumina, silica, and diol to the
fractionation and cleanup of sample extracts containing organochlorine pesticides and
polychlorinated biphenyls listed in SW-846 Methods 8080/8081, phthalate esters listed in
Method 8061, and phenolic compounds listed in Method 8040. Cartridge loading and the effects
of matrix interferents such as those present in corn oil and diesel hydrocarbons, and elemental
sulfur were investigated. Such interferents were selected because they mimic typical background
contamination in the presence of which the target compounds may need to be determined. In
addition to these synthetic matrices, several extracts of environmental samples were spiked with
the target analytes at known concentrations and were then fractionated using the solid-phase
extraction procedures. A draft protocol for the use of solid-phase extraction cartridges was
prepared and was tested with spiked synthetic matrices and spiked extracts of real samples.
The results of this study indicate that the use of solid-phase extraction cartridges for the
cleanup of sample extracts is feasible for a variety of matrices and target compounds. The use
of cartridges simplifies the cleanup procedure, especially when automated (robotic) systems are
used, reduces solvent and adsorbent usage and decreases labor cost in sample preparation. Also
included in this report as an appendix is a literature review covering the state-of-the-art
technology on the solid-phase extraction cartridges and their use in extract cleanup/fractionation.
IV
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TABLE OF CONTENTS
Section Page
1 INTRODUCTION !
2 CONCLUSIONS 2
3 RECOMMENDATIONS 3
4 EXPERIMENTAL 4
5 RESULTS AND DISCUSSION 13
5.1 ORGANOCHLORINE PESTICIDES AND
POLYCHLORINATED BEPHENYLS 13
5.2 PHTHALATE ESTERS 30
5.3 PHENOLS 44
5.4 EVALUATION OF THE ASPEC SYSTEM 54
REFERENCES 69
APPENDIX A - EVALUATION OF SAMPLE EXTRACT CLEANUP
USING SPE CARTRIDGES - LITERATURE
REVIEW A-l
APPENDIX B - METHOD 3670 -- SAMPLE EXTRACT CLEANUP
USING SPE CARTRIDGES (DRAFT PROTOCOL) . . B-l
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FIGURES
Number Page
1 GC/ECD chromatograms of Method 8081 organochlorine pesticides
analyzed on a DB-608/DB-1701 column pair 10
2 GC/ECD chromatograms of a phthalate esters standard analyzed on the
DB-608/DB-1701 column pair 11
3 GC/ECD chromatograms of the PFB derivatives of phenolic compounds
analyzed on the DB-1701/DB-5 column pair 12
4 GC/ECD chromatograms of a Method 8081 organochlorine pesticide
standard containing elemental sulfur, passed through a silica cartridge 33
5 GC/ECD chromatograms of a Method 8081 organochlorine pesticide
standard containing elemental sulfur, passed through a diol cartridge 34
6 GC/ECD chromatograms of a phthalate esters standard spiked with
organochlorine pesticides and elemental sulfur and eluted from the 1-g
Florisil cartridge with hexane with 10 percent acetone 40
7 GC/ECD chromatograms of a phthalate esters standard spiked with
organochlorine pesticides and elemental sulfur and eluted from the 1-g
alumina cartridge with hexane with 20 percent acetone 41
VI
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TABLES
Number Page
1 Retention times and relative retention times of organochlorine pesticides
analyzed on the DB-608/DB-1701 column pair 5
2 Retention times and relative retention times of phthalate esters analyzed
on the DB-608/DB-1701 column pair 6
3 Retention times and relative retention times of the PFB derivatives of
phenolic compounds analyzed on the DB-1701/DB-5 column pair 7
4 Samples used in method development 9
5 Elution patterns and percent recoveries of the organochlorine pesticides
from silica cartridges 15
6 Elution patterns and percent recoveries of the organochlorine pesticides
from Florisil cartridges 16
7 Percent recoveries of the Aroclors from Florisil and silica cartridges 17
8 Elution patterns and percent recoveries of the organochlorine pesticides
from Florisil cartridges 18
9 Elution patterns and percent recoveries of the organochlorine pesticides
from silica cartridges 19
10 Elution patterns and percent recoveries of the organochlorine pesticides
and Aroclor 1260 from silica cartridges 20
11 Percent recoveries and elution patterns of 17 organochlorine pesticides
from 0.5-g silica cartridges 22
12 Percent recoveries and elution patterns of 17 organochlorine pesticides
from 1-g silica cartridges 23
13 Percent recoveries and elution patterns of 17 organochlorine pesticides
from 2-g silica cartridges 24
14 Elution patterns and percent recoveries of 17 organochlorine pesticides
from 0.5-g diol cartridges 25
15 Elution patterns and percent recoveries of 17 organochlorine pesticides
from 1-g diol cartridges 26
16 Elution patterns and percent recoveries of 17 organochlorine pesticides
from 2-g diol cartridges 27
vu
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TABLES (continued)
Number Page
17 Elution patterns and percent recoveries of 17 organochlorine pesticides and
Aroclor 1260 from 1-g diol cartridges 29
18 Percent recoveries and elution patterns of 17 organochlorine pesticides
from 1-g silica cartridges in the presence of corn oil and diesel
hydrocarbons 31
19 Percent recoveries and elution patterns of 17 organochlorine pesticides
from 1-g diol cartridges in the presence of corn oil and diesel
hydrocarbons 32
20 Elution patterns and percent recoveries of the phthalate esters from the
Florisil cartridges using hexane with 10 percent acetone 35
21 Elution patterns and percent recoveries of the phthalate esters from the
alumina cartridges using hexane with 10 percent and 20 percent acetone .... 36
22 Elution patterns and percent recoveries of the phthalate esters from the
alumina cartridges of various sizes using hexane with 20 percent acetone .... 37
23 Percent recoveries of the phthalate esters from Florisil and alumina
cartridges when interferents were present 39
24 Elution patterns and percent recoveries of phthalate esters from Florisil
cartridges using hexane with 50 percent diethyl ether 42
25 Results of the Florisil cartridge cleanup evaluation study (phthalate ester
standards only; elution with hexane/methylene chloride (4:1) and
hexane/acetone (9:1)) 43
26 Experimental design for Florisil cartridge cleanup method development 45
27 Recovery of phthalate esters from 1-g Florisil cartridges 48
28 Recovery of phthalate esters from 1-g Florisil cartridges in the presence
of organochlorine pesticides 49
29 Interferences in the determination of phthalate esters caused by
organochlorine pesticides 50
30 Results of method blank analyses for the Florisil cartridges 51
Vlll
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TABLES (concluded)
Number
31 Percent recoveries of phthalate esters in extracts from various matrices
subjected to Florisil cartridge cleanup 52
32 Method detection limit study - Florisil cartridges method blanks 53
33 Elution patterns and percent recoveries of the PFB derivatives of phenols
from 0.5-g silica cartridges 55
34 Elution patterns and percent recoveries of the PFB derivatives of phenols
from 1-g silica cartridges 56
35 Elution patterns and percent recoveries of the PFB derivatives of phenols
from 2-g silica cartridges 57
36 Percent recoveries and elution patterns of phenols from 1-g silica cartridges
in the presence of corn oil and diesel hydrocarbons 58
37 Percent recoveries and elution patterns of phenols from 1-g silica cartridges
in the presence of matrix interferents 59
38 Method reproducibility using the ASPEC robotic system 60
39 Method reproducibility using the ASPEC robotic system 61
40 Method reproducibility using the ASPEC robotic system 62
41 Evaluation of matrix interferents using the ASPEC robotic system 63
42 Percent recoveries of 17 organochlorine pesticides spiked into SS-2 soil
extract 64
43 Percent recoveries of 17 organochlorine pesticides spiked into SS-5 soil
extract 65
44 Percent recoveries of 17 organochlorine pesticides spiked into SS-7 soil
extract 66
45 Percent recoveries of 17 organochlorine pesticides spiked into SS-8 soil
extract 67
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SECTION 1
INTRODUCTION
Fractionation or cleanup of sample extracts prior to instrumental analysis for organic
compounds (e.g., gas chromatography) is used to remove coextracted materials that interfere
with the determination of target analytes. Such fractionations are usually accomplished by
column chromatography (e.g., on Florisil, alumina, silica gel), gel permeation chromatography,
or acid-base partitioning. More elaborate fractionation schemes that involve a combination of
such cleanup procedures can be quite tedious, and experienced analysts are required for their
successful application.
Standardized cleanup procedures such as Methods 3610 and 3620, published in the
Office of Solid Waste Manual SW-846, revised recently (1), specify amounts of alumina and
Florisil in excess of 10 g and large volumes of eluting solvents. For example, a 10-g Florisil
column and 100 mL of 20 percent diethyl ether in hexane are recommended for cleanup of
sample extracts containing phthalate esters. Such large volumes of solvents increase the
likelihood of sample contamination by impurities present in solvents. Furthermore, the
adsorbent materials and the solvents are not recycled, and although such materials are not overly
expensive, the time required for the preparation of the adsorbent, for the packing of the
chromatographic columns, for the elution of the target analytes from the columns, and for the
evaporation of solvents contributes to the overall cost of analysis.
The purpose of this study was to evaluate the application of solid-phase extraction
cartridges containing Florisil, alumina, silica, and diol to the fractionation/cleanup of sample
extracts containing organochlorine pesticides and polychlorinated biphenyls listed in SW-846
Methods 8080/8081, phthalate esters listed in Method 8060, and phenolic compounds listed in
Method 8040. Cartridge loading and the effects of matrix interferents such as those present in
corn oil and diesel hydrocarbons, and elemental sulfur were investigated. Such interferents were
selected because they mimic typical background contamination in the presence of which the
target compounds may have to be determined. For example, corn oil is representative of the
fatty acid triglycerides, and diesel hydrocarbons are representative of petroleum hydrocarbons.
Elemental sulfur was chosen because this compound is extracted from soils or sediments along
with target analytes and interferes with their gas chrpmatpgraphic determination, especially when
an electron capture detector is used for compound identification and quantification. In addition
to these synthetic matrices, we have also used extracts of real samples which were spiked with
the target analytes at known concentrations and were then fractionated using the solid-phase
extraction cartridge procedure.
Subsequent sections of this report present the conclusions and recommendations of this
study, details of the experimental procedures, and the results and discussion. Appendix A
contains the literature review summary, and the protocol for sample extract cleanup is included
as Appendix B.
1
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SECTION 2
CONCLUSIONS
Currently, there are no EPA-approved sample extract cleanup procedures that specify
the use of solid-phase extraction (SPE) cartridges. The only methods specifying SPE cartridges
are Test Method No. SPE-500, Methods for Organochlorine Pesticides and Chlorophenoxy Acid
Herbicides in Drinking Water and Raw Source Water for Endrin, Lindane, Methoxychlor, and
Toxaphene, and Method 525, Determination of Organic Compounds in Drinking Water by
Liquid-Solid Extraction and Capillary Column Gas Chromatography/Mass Spectrometry. Both
methods use such cartridges for sample preconcentration and not for cleaning or fractionating
the sample extract. Work presented in this report involves the development of such simplified
extract cleanup procedures for use with methods presented in the EPA's SW-846 procedures
manual.
Use of SPE cartridges reduces solvent and adsorbent usage and labor cost in sample
preparation. Because cartridges are prepackaged and ready for use, there is no need for
adsorbent calibration, activation, or deactivation. Furthermore, when commercially available
automated systems are used, sets of 12 or 24 extracts, depending on the capacity of the vacuum
manifold, can be cleaned up simultaneously with no danger of sample crosscontamination; thus,
sample throughput can be increased significantly. In addition, errors resulting from operator and
material variables that may affect the quality of the results can be minimized.
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SECTION 3
RECOMMENDATIONS
The protocol for extract cleanup using SPE cartridges which is presented in this
report has been evaluated in a single laboratory only with a few relevant sample
extracts. To establish the applicability range of the cartridge method and to define
the interlaboratory method performance, the protocol should be evaluated by other
laboratories and with additional samples.
Use of SPE cartridges helps increase sample throughput, and reduces solvent and
adsorbent usage and labor cost in sample preparation. To take full advantage of
these benefits, automation of the sample extract step should be explored. Several
robotics systems which are available commercially should be evaluated.
Bonded-phase silicas and polymeric materials such as those available from
Interaction Chemicals of Mountain View, California, should be evaluated for
removal of matrix interferents present in extracts of soils, sediments, and other
environmental matrices, and for fractionation of analytes of environmental
significance.
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SECTION 4
EXPERIMENTAL
Apparatus
a. Vacuum manifold — VacElute manifold SPS24 (Anatytichem International) or Visiprep
(Supelco Inc.) or equivalent, consisting of glass vacuum basin, collection rack and funnel,
collection vials, replaceable stainless steel delivery tips, built-in vacuum bleed valve and
gauge; the system was connected to a vacuum pump or water aspirator through a vacuum
trap made from a 500-mL side arm flask fitted with a one-hole stopper and glass tubing.
b. ASPEC robotic system (Gilson Medical Electronics, Inc) consisting of a sample processor and
injector module and the Gilson fluid transfer unit (Model 401 Dilutor).
c. Gas chromatographs - Varian 6000 with constant current/pulsed frequency dual electron
capture detector (ECD) and interfaced to a Varian Vista 402 data system; Varian 6500 with
constant current/pulsed frequency dual ECD and interfaced to a Varian Vista 604 data
system.
d. Autosampler - Varian, Model 8000
e. GC columns -- DB-608 and DB-1701,30-m x 0.53-mm ID fused-silica open tubular columns
for Method 8060 phthalate ester analysis and Method 8080 organochlorine
pesticide/polychlorinated biphenyls analysis; DB-5 and DB-1701, 30-m x 0.53-mm ID fused-
silica open tubular columns for Method 8040 phenol analysis. The GC operating conditions
are given in Tables 1 through 3.
Materials
a. Cartridges - Florisil, alumina, silica gel, or diol (40-jim particles, 60-A pores) of 0.5 g, 1 g,
and 2 g in size. The cartridges consist of serological-grade polypropylene tubes, 3 mL or
6 mL in volume; the adsorbent material is held between two polyethylene frits (30-/im pores).
b. Standards - Analytical reference standards of the test compounds were obtained from the
U.S. Environmental Protection Agency, Pesticides and Industrial Chemical Repository,
Aldrich Chemical, Ultra Scientific Inc., Chem Service, and Scientific Polymer Products.
Purities were stated to be greater than 98 percent. Stock solutions of each test compound
were prepared by serial dilutions of a composite stock solution prepared from the industrial
stock solutions.
c. Corn oil -- Stock solution was prepared in hexane at 1.1 mg/mL.
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TABLE 1. RETENTION TIMES AND RELATIVE RETENTION TIMES OF ORGANO-
CHLORINE PESTICIDES ANALYZED ON THE DB-608/DB-1701 COLUMN
PAIR"
DB-608 DB-1701
Compound
No. Compound name tr (min) RRT tr (min) RRT
1 alpha-BHC 9.79 0.912 10.22 0.953
2 gamma-BHC 11.28 1.051 11.64 1.086
3 beta-BHC 11.59 1.080 14.18 1.323
4 Heptachlor 12.47 1.162 12.41 1.158
5 delta-BHC 12.97 1.209 15.02 1.401
6 Aldrin 13.69 1.276 13.37 1.247
7 Heptachlor epoxide 15.84 1.476 15.79 1.473
8 Endosulfanl 17.13 1.596 16.73 1.561
9 4,4'-DDE 18.06 1.683 17.41 1.624
10 Dieldrin 18.28 1.704 17.99 1.678
11 Endrin 19.63 1.829 18.72 1.746
12 4,4'-ODD 20.14 1.877 20.07 1.872
13 Endosulfanll 20.32 1.894 20.32 1.896
14 4,4'-DDT 21.22 1.978 20.68 1.929
15 Endrin aldehyde 21.54 2.007 21.71 2.025
16 Endosulfan sulfate 21.99 2.049 22.81 2.128
17 4,4'-Methoxychlor 24.48 2.281 22.81 2.128
Pentachloronitrobenzene (IS)b 10.73 1.000 10.72 1.000
"The GC operating conditions were as follows: 30-m x 0.53-mm ID DB-608 (0.83-/im film)
and 30-m x 0.53-mm ID DB-1701 (1.0-/im film) connected to an 8-in injection tee (Supelco,
Inc.). Temperature program: 150°C (0.5-min hold) to 2758C (15-min hold) at 5CC; injector
temperature 250°C; detector temperature 320°C; helium carrier gas 6 mL/min; nitrogen
makeup gas 20 mL/min.
Internal standard.
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TABLE 2. RETENTION TIMES AND RELATIVE RETENTION TIMES OF PHTHALATE
ESTERS ANALYZED ON THE DB-608/DB-1701 COLUMN PAIR"
o\
DB-608
Compound
no.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
Compound name
Dimethyl phthalate (DMP)
Diethyl phthalate (DEP)
Diisobutyl phthalate (DIBP)
Di-n-butyl phthalate (DBF)
Bis(4-methyl-2-pentyl) phthalate (BMPP)
Bis(2-methoxyethyl) phthalate (BMEP)
Diamyl phthalate (DAP)
Bis(2-ethoxyethyl) phthalate (BEEP)
Dihexyl phthalate (DHP)
Hexyl 2-ethylhexyl phthalate (HEHP)
Butyl benzyl phthalate (BBP)
Bis(2-n-butoxyethyl) phthalate (BBEP)
Bis(2-ethylhexyl) phthalate (DEHP)
Dicyclohexyl phthalate (DCP)
Di-n-octyl phthalate (DOP)
Dinonyl phthalate (DNP)
Benzyl benzoate (IS)b
tr (min)
6.72
8.69
12.74
14.68
15.76
17.24
17.94
18.93
19.70
21.50
24.64
25.71
24.94
28.33
29.14
32.97
12.13
RRT
0.554
0.716
1.050
1.210
1.299
1.421
1.479
1.561
1.624
1.772
2.031
2.120
2.056
2.336
2.402
2.718
1.000
DB-170I
tr (min)
6.73
8.85
13.36
15.13
16.73
16.96
18.64
18.80
19.56
22.48
23.76
25.96
26.35
27.06
30.57
34.71
11.50
RRT
0.585
0.770
1.162
1.316
1.455
1.475
1.621
1.635
1.701
1.955
2.066
2.257
2.291
2.353
2.658
3.018
1.000
*GC operating conditions were as follows: 30-m x 0.53-mm ID DB-608 (0.83-/im film) and 30-m x
0.53-m ID DB-1701 (1.0-/im film) connected to an 8-in injection tee (Supelco, Inc.). Temperature
program: 150°C (0.5-min hold) to 220°C at 5°C/min, then to 275°C (18-min hold) at 3°C/min;
injector temperature 250°C; detector temperature 320°C; helium carrier gas 6 mL/min; nitrogen
makeup gas 20 mL/min.
b Internal standard.
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TABLE 3. RETENTION TIMES AND RELATIVE RETENTION TIMES OF THE PFB
DERIVATIVES OF PHENOLIC COMPOUNDS ANALYZED ON THE
DB-1701/DB-5 COLUMN
DB-1701
DB-5
Compound
no.
Compound name
tr (min) RRT
tr (min) RRT
1 Phenol 7.76 0.518
2 2-Methylphenol 9.03 0.603
3 3-Methylphenol 9.62 0.643
4 4-Methylphenol 9.76 0.652
5 2,4-Dimethylphenol 10.83 0.723
6 2-Chlorophenol 11.76 0.786
7 2,6-Dichlorophenol 13.70 0.915
8 4-Chloro-3-methylphenol 14.33 0.957
9 2,4-Dichlorophenol 15.56 1.039
10 2,4,6-Trichlorophenol 16.20 1.082
11 2,3,6-Trichlorophenol 17.38 1.161
12 2-Nitrophenol 18.59 1.242
13 2,4,5-Trichlorophenol 18.72 1.251
14 2,3,5-Trichlorophenol 18.75 1.253
15 2,3,5,6-Tetrachlorophenol 19.98 1.335
16 2,3,4,6-Tetrachlorophenol 20.21 1.350
17 2,3,4-Trichlorophenol 20.34 1.359
18 2,3,4,5-Tetrachlorophenol 22.79 1.522
19 Pentachlorophenol 23.64 1.579
20 2,4-Dinitrophenol 28.07 1.875
Pentachloronitrobenzene (IS)d 14.97 1.000
5.40
6.73
7.20
7.38
8.62
8.67
10.98
11.42
12.22
13.66
14.51
13.38
15.29
15.36
17.23
17.45
16.57
19.12
20.76
20.78
0.446
0.556
0.595
0.610
0.712
0.717
0.907
0.944
1.010
1.129
1.199
1.106
1.264
1.269
1.424
1.442
1.369
1.580
1.716
1.717
12.10 1.000
8 Not able to obtain a detector response from 4-nitrophenol, dinoseb, or 4,6-dinitro-o-cresol
PFB derivatives.
b GC operating conditions were as follows: 30-m x 0.53-mm ED DB-5 (0.83-/ttn film) and
30-m x 0.53-mm ID DB-1701 (1.0-0m film) connected to an 8-inch injection tee (Supelco,
Inc.). Temperature program: 150°C (5 min hold) to 275°C (15 min hold) at 5°C/min;
injector temperature 250°C; detector temperature 320°C; helium carrier gas 6 mL/min;
nitrogen makeup gas 20 mL/min.
c Phenols were derivatized with pentafluorobenzyl bromide (PFBBr) following the procedure
by Lee et al. (2).
d Internal standard.
-------
d. Diesel hydrocarbons - Stock.solution was prepared in hexane at 1 mg/mL.
e. Elemental sulfur - Stock solution was prepared in hexane at 0.28 mg/mL.
f. Samples - Those used in the method development are identified in Table 4.
Cartridge Cleanup Procedure
Florisil cartridges were conditioned with 4 mL hexane prior to use. Diol cartridges were
conditioned with hexane with 10 percent acetone. Silica cartridges were conditioned with 4 mL
hexane. Aliquots of 2 mL of standards or sample extracts in hexane were loaded onto SPE
cartridges using a micropipette and were eluted with the solvents indicated in the tables
summarizing the data. A Supelclean Visiprep vacuum manifold (Supelco, Inc.) and a
VacElute SPS24 (Analytichem International) were used to simultaneously prepare as many as
12 samples (for the Visiprep system) or 24 samples (for the VacElute SPS24 system). When
using the Visiprep system, the vacuum for each cartridge was adjusted manually using chemically
inert screw-type valves. Additional details of the cartridge cleanup procedure can be found in
the protocol included in Appendix B of this report.
Gas Chromatographic Analysis
All fractions were analyzed by gas chromatography with ECD using the dual-column
approach. The retention times and the relative retention times of the target compounds are
presented in Tables 1 through 3. Figures 1 through 3 show GC/ECD chromatograms obtained
for each group of target compounds. Quantification of compounds was performed using internal
standard calibrations.
-------
TABLE 4. SAMPLES USED IN METHOD DEVELOPMENT
Material
Description
Sandy loam soil
Sediment of undefined origin
SRM-1572
SRM-1632a
SRM-1633a
Sample 1
Sample 2
Sample 3
Samples SS-2, SS-5, SS-7
and SS-8
Mixture of 20 percent organic soil and 80 percent sand
Sediment sample contaminated with petroleum
hydrocarbons
Citrus leaves from Lake Alfred area of central Florida.
The material was air-dried, ground to pass through a
425-/im screen, dried at 85°C, mixed in a feed blender,
and sterilized with cobalt-60 radiation.
Coal obtained from the Humphrey No. 7 mine and coal
preparation plant of the Consolidation Coal Co., Osage,
West Virginia. Contains approximately 1.8 to
1.9 percent sulfur and was ground to pass through a
60-mesh sieve.
Coal flyash, obtained from a coal-fired power plant that
uses Pennsylvania and West Virginia coals. The material
was sieved to pass through a 90-/im screen.
Soil sample taken from a greenhouse, identified as S-2A
greenhouse south; known to contain 4,4'-DDE at
460 /ig/Kg
Soil sample known to contain ppm levels of polynuclear
aromatic hydrocarbons
Soil sample known to contain 4,4 '-DDE at 4000 /ig/Kg
and 4,4'-ODD at 34,000 /ig/Kg
Soil samples taken from a farm in Northern California,
which was known to have used organochlorine pesticides,
diazinon, ethion, ziram, carbaryl, benomyl,
carbophenothion, and malathion.
-------
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-5
DB-608
10
12
11
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I
DB-1701
10 20
TIME (min)
30
Figure 1. GC/ECD dlromatognuns of Method 8081 organodllorine pesticides analyzed on a
DB-608/DB-1701 column pair. The GC operating conditions are given in Table 1.
10
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«: i-
T- <
tv
r
6
5
0*' 0"i V
Og o C9 1
TTIVJ N ^>
T1 «c r-
9 10
in 11 ,-.1715 18 19
131
14
16
20
DB-5
30 m x 0.53 mm ID
0.83 |im film
Figure 3. GC/ECD chromatograms of the PFB derivatives of phenolic compounds analyzed on
the DB-1701/DB-5 column pair. The GC operating conditions and peak assignments
are given in Table 3.
12
-------
SECTION 5
RESULTS AND DISCUSSION
5.1 ORGANOCHLORINE PESTICIDES AND POLYCHLORINATED BIPHENYLS
The current SW-846 Methods 8080/8081 for organochlorine pesticides and
polychlorinated biphenyls (PCBs) determination recommend use of either Florisil (Method 3620)
or silica gel for cleanup of sample extracts containing organochlorine pesticides and PCBs. In
Method 3620, Florisil (60/80 mesh) is activated for 16 hrs at 130°C. The charged Florisil column
(10 g) is eluted with 200 mL of 6 percent diethyl ether in hexane (Fraction 1), 200 mL of
15 percent diethyl ether in hexane (Fraction 2), and 200 mL of 50 percent diethyl ether in
hexane (Fraction 3). Compounds recovered in Fraction 1 include aldrin, the four BHC isomers,
chlordane, 4,4 '-DDD, 4,4'-DDE, 4,4'-DDT, endosulfan I, heptachlor, heptachlor epoxide,
toxaphene, and the PCBs. Compounds recovered in Fraction 2 include dieldrin, endosulfan I,
endrin, and endrin aldehyde. Endosulfan II, endosulfan sulfate, and some endrin aldehyde are
recovered in Fraction 3. We evaluated Method 3620 and reported that, although compound
recoveries were quantitative, the Florisil fractionation method is not suitable for samples that
contain both organochlorine pesticides and PCBs (3) since the PCBs are eluted in the same
fraction as the bulk of the organochlorine pesticides. We undertook the evaluation of the
Florisil cartridges specifically for samples that contain only the organochlorine pesticides. The
silica cartridges were considered since Method 8081 describes a procedure in which PCBs can
be separated from the bulk of the organochlorine pesticides using silica gel deactivated with
3 percent water. Finally, diol cartridges were evaluated since at the time our study was
conducted, EPA was considering the use of diol cartridges for incorporation into the Contract
Laboratory Program protocols. This section describes the results of the Florisil, silica, and diol
cartridge evaluation studies.
Two elution schemes were attempted initially. In Scheme A, the charged Florisil and
silica cartridges were eluted with 3 mL hexane (Fraction 1) followed by 5 mL hexane with
26 percent methylene chloride (Fraction 2) and 5 mL hexane with 10 percent acetone
(Fraction 3); in Scheme B, the charged Florisil and silica cartridges were eluted with 3 mL
hexane (Fraction 1), 5 mL hexane with 4 percent diethyl ether (Fraction 2), and 5 mL hexane
with 56 percent diethyl ether (Fraction 3). Hexane with 26 percent methylene chloride has
approximately the same solvent strength as hexane with 4 percent diethyl ether, and hexane with
10 percent acetone has approximately the same solvent strength as hexane with 56 percent
diethyl ether. Under the Scheme A conditions, silica gel proved superior to Florisil because it
allowed complete separation of the PCBs from all but four organochlorine pesticides,
quantitative recovery of all compounds, and almost complete separation of the Method 8081
organochlorine pesticides from the Method 8060 phthalate esters. The four organochlorine
pesticides that eluted with the 16 phthalate esters could be identified and quantified without any
difficulty because they were resolved from the phthalate esters on a 30-m x 0.25-mm ID DB-5
fused-silica capillary column.
13
-------
The solvents used in Scheme B gave almost identical elution patterns for the Florisil and
silica gel procedure with quite a few organochlorine pesticides spread among the three fractions.
Because of this, no further work was undertaken using Scheme B.
The procedure given in Scheme A was tested at 2 organochlorine pesticide
concentrations in quadruplicate. The results presented in Tables 5 and 6 show elution patterns,
compound recoveries, and method precision for the 17-organochlorine pesticides listed in
Table 1 and gamma-chlordane. The silica gel cartridges seemed to perform better than the
Florisil cartridges (Table 5). Three organochlorine pesticides (heptachlor, aldrin, and 4,4 '-DDE)
were eluted only in Fraction 1. Nine organochlorine pesticides (the four BHC isomers,
heptachlor epoxide, gamma-chlordane, endosulfan I, dieldrin, and 4,4 '-DDD) were eluted only
in Fraction 2. Endosulfan II was eluted in Fraction 3. Endrin aldehyde, 4,4'-DDT, endosulfan
sulfate and 4,4 '-methoxychlor were eluted in more than one fraction. Compound recoveries
were quantitative and method precision (%RSD) was better than 11 percent for 14 of the 18
target compounds. Since endosulfan sulfate was not resolved from 4,4'-DDT on the 30-m x
0.25-mm ID DB-5 column, it is difficult to specify in which fraction this compound was
recovered. Based on the other data presented in this section, it is expected that endosulfan
sulfate would elute in Fraction 3 from either the silica cartridge (Table 5) or the Florisil
cartridge (Table 6).
Table 6 presents the results for the Florisil SPE cartridge procedure. Eight pesticides
(alpha-BHC, gamma-BHC, heptachlor, aldrin, gamma-chlordane, 4,4'-DDE, 4,4'-DDD, and
4,4'-DDT) were eluted in Fraction 1. All pesticides except heptachlor, aldrin, and 4,4'-DDE
were also recovered in Fraction 2. Endosulfan II, endrin aldehyde, possibly endosulfan sulfate
and 4,4'-methoxychlor were also eluted in Fraction 3.
Seven Aroclor mixtures were tested individually on the silica and the Florisil cartridges.
In each case, the cartridges were loaded with 10 Mg of the corresponding Aroclor and were
eluted with 3 mL hexane. The recovery data given in Table 7 indicate that the Aroclors were
recovered quantitatively from either cartridge with 3 mL hexane. Larger cartridges may require
additional solvent to ensure complete removal of PCBs.
Other solvent mixtures used in eluting the organochlorine pesticides from 1-g Florisil
and silica cartridges included hexane, hexane with 6 percent diethyl ether, hexane with
15 percent diethyl ether, and hexane with 50 percent diethyl ether (Tables 8 and 9). The Florisil
cartridge is somewhat less polar than the silica cartridge, and more organochlorine pesticides
were eluted from the Florisil cartridge with hexane.
To reduce the number of fractions that have to be collected in order to recover all
18 organochlorine pesticides, we eluted the silica cartridges with two 3-mL hexane portions and
5 mL of hexane with 50 percent diethyl ether. At least 3 mL hexane need to be passed through
the silica cartridge to elute any PCBs that would interfere with the gas chromatographic analysis
of the organochlorine pesticides. The second 3-mL hexane portion was used to verify the
complete removal of PCBs from the cartridge (Table 10). Elution of silica cartridges with 5 mL
hexane with 50 percent diethyl ether resulted in quantitative recovery of all organochlorine
pesticides retained on the cartridge.
This elution scheme was further tested with silica cartridges of 0.5-g, 1-g, and 2-g size,
each charged with 17 organochlorine compounds at 02 Jig, 1.0 Jig, and 2.0 jtg per cartridge.
Gamma-chlordane was not included among the target compounds because it was not available
in pure form at the time the study began. Two fractions were collected from the 0.5-g and 1-g
14
-------
o\
TABLE 6. ELUTION PATTERNS AND PERCENT RECOVERIES OF THE ORGANO-
CHLORINE PESTICIDES FROM FLORISIL CARTRIDGES'
Spiked at 0.5
Frarlinn 1
(3 ml. hexane)
Compound
alpha-BHC
gamma-BHC
bela-BHC
Heptachlor
delta-BHC
Aldrin
Heptachlor epoxide
gamma-Chlordane
Endosulfan I
4.4 '-DDE
Dkldrin
Endrin
4.4 '-ODD
Endosulfan II
Endrin aldehyde
4.4--DDT
Endosulfan sulfate*
4,4'-Melhoxychlor
Avg.
82.6
35.8
0
94.4
0
93.1
0
47.6
0
94.5
0
0
38.5
0
0
49.6
0
%KSI>
3.4
13.3
2.3
2.0
9.8
1.7
12.3
1.9
/Jg per compound
Fraction 2
(5 mL hexane with
26 percent
melhylene chloride)
Avg.
26.3
77.5
102
0
99.6
0
102
65.6
101
0
101
57.2
6R.8
58.2
36.3
11.2
96.0
%RSI)
10.7
3.1
2.3
1.4
2.4
3.5
2.7
2.9
7.5
2.9
13.3
7.2
16.4
3.4
Fraction 3
(5 mL hexane with
10 percent acetone)
Avg. %RSD
0
0
0
0
0
0
0
0
0
0
0
0
0
61.1 9.9
78.7 2.6
59.4 3.1
11.7 3.0
Spiked at 5.0 UK per compound
Fraction 1
(3 mL hexane)
Avg.
79.0
32.0
0
94.8
0
94.6
0
44.2
0
96.8
0
b
37.7
0
0
51.6
0
%RSI>
13.7
20.9
14.8
14.2
18.0
14.9
19.9
15.0
Fraction 2
(5 mL hexane with
26 percent
melhylene chloride)
Avg.
34.1
82.8
104
0
103
0
104
73.2
104
0
105
b
77.3
60.3
47.5
12.2
105
%RSD
5.6
3.8
3.6
2.3
3.9
5.4
4.3
4.4
4.9
5.2
2.7
13.7
5.5
Fraction 3
(5 mL hexane with
10 percent acetone
Avg.
0
0
0
0
0
0
0
0
0
0
0
b
0
58.3
72.7
56.8
11.2
%RSI)
10.8
6.7
9.8
15.0
M-g LC-Florisil cartridges (Supelco Inc.) were used. The amount of compound loaded In the cartridge is 0.5 fig or 5.0 /ig per compound (or 2 mL of a
0.25-pg/mL or 2.5-Jlg/mL solution in hexane). Fraction I was eluted with 3 mL hexane, Fraction 2 with 5 mL hexane with 26 percent methylene chloride, and
Fraction 3 with 5 mL hexane with 10 percent acetone. Number of replicates was 4.
'Data not available due to poor chromatography on the 30-m x 0.25-mm ID DB-5 fused-silica capillary column.
'These compounds coelute on the 30-m x 0.25 mm ID DB-5 fused-silica capillary column.
-------
TABLE 5. ELUTION PATTERNS AND PERCENT RECOVERIES OF THE ORGANO-
CHLORINE PESTICIDES FROM SILICA CARTRIDGES"
Spiked at 0.5 /ig per compound
Fraction 2
(5 mL hexane with
Fraction 1 26 percent
(3 mL hexane) methylene chloride)
Compound
alpha-BHC
gamma-BHC
heta-BHC
Hcptachlor
delta-BHC
Aldrin
Heptadilor epoxide
gamma-Chlordane
Endosulfan I
4,4 '-DDE
Dieldrin
Endrin"
4.4 '-ODD
Endosulfan II
4,4'- OUT
Endrin aldehyde
Endosulfan sulfate*
4,4'-Methoxychlor
Avg.
0
0
0
98.4
0
96.6
0
0
0
104
0
»
0
0
40.1
0
0
%KSD Avg.
Ill
no
109
10.8 0
106
9.9 0
109
105
HI
5.7 0
110
b
ill
0
25.5 16.7
48.9
84.5
%RSI)
8.3
8.5
7.8
9.3
7.9
3.5
6.2
7.8
6.2
24.3
14.0
22.2
Spiked at 5.0 /ig per compound
Fraction 2
Fraction 3 (5 mL hexane with
(5 mL hexane in Fraction 1 26 percent
10 percent acetone) (3 mL hexane) methylene chloride)
Avg.
0
0
0
0
0
0
0
0
0
0
0
b
0
111
63.4
47.7
33.6
%RSI) Avg.
0
0
0
105
0
108
0
0
0
109
0
b
0
2.3 0
3.2 44.6
12.4 0
29.0 0
%RSI) Avg.
Ill
III
III
1.0 0
110
0.9 0
112
108
114
1.1 0
114
b
114
0
10.3 19.4
52.4
94.3
%RSI>
2.4
2.3
2.7
3.5
2.8
6.5
2.6
2.4
3.3
25.9
3.1
10.4
Fraction 3
(5 mL hexane in
10 percent acetone)
AYR.
0
0
0
0
0
0
0
0
0
0
0
h
0
no
63.3
41.9
26.1
%KSI)
3.0
4.1
9.9
10.2
M-g LC-silica cartridges (Supelco Inc.) were used. The amount of compound loaded to the cartridge is 0.5 or 5.0 0g per compound (or 2 mL of a 0.25-/Jg/mL or
25-pg/mL solution in hexane). Fraction 1 was eluted with 3 mL hexane. Fraction 2 with 5 mL hexane with 26 percent methylene chloride, and Fraction 3 with
5 mL hexane with 10 percent acetone. Number of replicates was 4.
'Data not available due to poor chromatography on the 30-m x 0.25-mm ID DB-5 fused-silica capillary column.
'These compounds coelute on the 30-m x 0.25-mm ID DB-5 fused-silica capillary column.
-------
TABLE 7. PERCENT RECOVERIES OF THE AROCLORS
FROM FLORISIL AND SILICA CARTRIDGES
Compound
Aroclor 1016
Aroclor 1221
Aroclor 1232
Aroclor 1242
Aroclor 1248
Aroclor 1254
Aroclor 1260
Percent
LC-FIorisii
dg)
105
76.5
90.1
93.6
97.2
95.4
89.7
recovery"
LC-Silica
(1 g)
124
93.5
118
116
114
108
112
a 1-g LC-Florisil or LC-silica solid-phase extraction
cartridges (Supelco Inc.) were used. The amount of
Aroclor loaded to each cartride is 10 Mg (or 2 mL of
5-/fg/mL solution in hexane). Hexane (3 mL) was
used as eluent.
17
-------
TABLE 8. ELUTION PATTERNS AND PERCENT RECOVERIES OF THE ORGANOCHLORINE
PESTICIDES FROM FLORISIL CARTRIDGES'
Fraction 2 Fraction 3 Fraction 4
(5 mL hexane (5 mL hexane (5 mL hexane
Fraction 1 with 6 percent with 15 percent with 50 percent
Compound (3 mL hexane) diethyl ether) diethyl ether) diethyl ether)
alpha-BHC
gamma-BHC
beta-BHC
Heptachlor
delta-BHC
Aldrin
Heptachlor epoxide
Endosulfan I
gamma-Chlordane
^ 4,4 '-DDE
00 Dieldrin
Endrin
4,4 '-DDD
Endosulfan II
4,4 '-DDT
Endrin aldehyde
Endosulfan sulfate
4,4'-Methoxychlor
88.7
60.0
0
88.8
0
90.7
0
0
70.5
0
0
0
0
76.0
87.8
0
0
0
24.4
66.1
87.0
3.6
27.3
4.2
94.5
94.9
0
79.2
105
0
0
70.4
0
0
113
94.4
0
0
0
0
81.4
0
0
0
0
0
0
62.8
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
81.7
84.0
0
0
117
0
0
"Single determination; 1-g LC-Florisil cartridges were used. The amount loaded to each cartridge was 10 /ig per compound.
-------
TABLE 9. ELUTION PATTERNS AND PERCENT RECOVERIES OF THE ORGANOCHLORINE
PESTICIDES FROM SILICA CARTRIDGES'
Fraction 2 Fraction 3 Fraction 4
(5 mL 6 percent (5 mL 15 percent (5 mL 50 percent
Fraction 1 diethyl ether diethyl ether diethyl ether
Compound (3 mL hexane) in hexane) in hexane) in hexane)
alpha-BHC
gamma-BHC
beta-BHC
Heptachlor
delta-BHC
Aldrin
Heptachlor epoxide
Endosulfan I
gamma-Chlordane
4,4 '-DDE
Dieldrin
Endrin
4,4 '-DDD
Endosulfan II
4,4 '-DDT
Endrin aldehyde
Endosulfan sulfate
4,4'-Methoxychlor
0
0
0
93.5
0
96.2
0
0
107
0
0
0
0
0
108
0
0
0
98.0
99.4
85.0
0
0
0
95.1
93.1
0
79.1
102
0
0
94.2
0
0
105
80.8
0
0
0
0
89.0
0
0
0
0
0
0
45.2
0
0
0
0
0
36.0
0
0
0
0
0
0
0
0
0
0
0
54.8
81.0
0
0
108
0
0
"Single determination; 1-g LC-silica cartridges were used. The amount loaded to each cartridge was 10 /ig per compound.
-------
TABLE 10. ELUTION PATTERNS AND PERCENT RECOVERIES OF THE
ORGANOCHLORINE PESTICIDES AND AROCLOR 1260 FROM SILICA
CARTRIDGES'
Fraction 3
(5 mL hexane with
Fraction 1 Fraction 2 50 percent
Compound (3 mL hexane) (3 mL hexane) diethyl ether)
Aroclor 1260
alpha-BHC
gamma-BHC
beta-BHC
Heptachlor
delta-BHC
Aldrin
Heptachlor epoxide
gamma-Chlordane
Endosulfan I
4,4 '-DDE
Dieldrin
Endrin
4,4 '-DDD
Endosulfan II
4,4 '-DDT
Endrin aldehyde
Endosulfan sulfate
4,4 '-Methoxychlor
101
0
0
0
101
0
102
0
75.1
0
0
0
0
0
0
85.9
0
0
0
0
59.5
0
0
8.1
0
7.4
0
8.1
0
0
0
0
0
59.8
0
0
90.4
0
0
61.1
101
101
0
95.1
0
103
0
103
82.1
117
107
68.4
40.2
0
112
0
103
aAroclor 1260 was spiked separately from the organochlorine pesticides. Single determination.
The amount loaded to the cartridge was 10 /ig per compound.
20
-------
cartridges. An additional 5 mL of hexane with 50 percent diethyl ether were passed through the
2.0-g cartridges to collect Fraction 3. The results are summarized in Tables 11 through 13. All
compounds, except endrin aldehyde, were recovered quantitatively (recovery >75 percent) in
the two or three fractions combined. The elution patterns seem to vary with the size of the
cartridge; however, they are very consistent within one cartridge size. For example, in the case
of the 0.5-g cartridges, 7 compounds, namely alpha-BHC, gamma-BHC, heptachlor, aldrin,
4,4'-DDE, 4,4 '-DDD, and 4,4'-DDT, were recovered in Fraction 1, and 13 compounds were
recovered in Fraction 2, demonstrating that some compounds are present in both fractions. The
number of compounds recovered in Fraction 1 from the 2-g cartridges decreased to three
(heptachlor, aldrin, and 4,4'-DDE), and an additional 5 mL of hexane with 50 percent diethyl
ether were needed to recover delta-BHC, endosulfan n, endrin aldehyde, and endosulfan sulfate
from the 2-g silica cartridge (Table 13).
At the time we were evaluating the Florisil and silica cartridges for their applicability
to the cleanup of sample extracts containing organochlorine pesticides, we came across a
protocol using diol cartridges (4). The diol procedure specifies use of 0.5-g and 1-g cartridges,
and elution of the organochlorine pesticides with hexane with 10 percent acetone. We evaluated
this procedure using 0.5-g, 1-g, and 2-g cartridges charged with the target organochlorine
pesticides at 0.2 /ig, 1.0 /ig, and 2.0 /ig per cartridge. Two fractions were collected from the
0.5-g and 1-g cartridges, and four fractions were collected from the 2-g cartridges. For the 1-g
cartridges charged at 2.0 /Jg per compound, we collected an additional fraction to verify that the
compounds were eluted quantitatively from the cartridge.
The data are summarized in Tables 14 through 16. At the 0.2-/ig spike level, sixteen
compounds eluted in Fraction 1 from the 0.5-g cartridges, and only two compounds (endrin
aldehyde and endosulfan sulfate) eluted in Fraction 2. Small amounts (recovery <6 percent) of
delta-BHC and endosulfan II were found in Fraction 2 from the cartridges spiked at 2.0 /ig per
cartridge. As the cartridge size was increased, more compounds were found in Fraction 2. For
example, in addition to delta-BHC and endosulfan n, endrin aldehyde and endosulfan sulfate
were detected in Fraction 2 from the 1-g cartridges spiked at 0.5 /ig and 2.0 fig per cartridge.
In addition, beta-BHC and small amounts of gamma-BHC and 4,4 '-methoxychlor were detected
in Fraction 2 from the 1-g cartridges spiked with 2.0 /ig. Finally, the elution patterns for the 2-g
cartridges were quite different from those of the 0.5-g and 1-g cartridges, and they also varied
with the amounts spiked on the cartridges (Table 16).
The diol procedure gave quantitative recoveries of the 17 organochlorine pesticides
when hexane with 10 percent acetone was used to elute the analytes; however, PCBs also eluted
in Fraction 1. An experiment was performed in which diol cartridges were eluted, first with
3 mL hexane (Fraction 1), then with two 5-mL portions of hexane with 10 percent acetone
(Fractions 2 and 3). Under those conditions, PCBs and heptachlor, aldrin, endosulfan I,
4,4'-DDE, and 4,4'-DDT were recovered in Fraction 1, and the remainder of the pesticides
eluted in Fraction 2, with most of the endrin aldehyde and endosulfan sulfate eluting in
Fraction 3 (Table 17).
Matrix interferents such as corn ofl, diesel hydrocarbons, and elemental sulfur, were
added to hexane solutions containing the target analytes at known concentrations, and the
21
-------
TABLE 11. PERCENT RECOVERIES AND ELUTION PATTERNS OF 17 ORGANOCHLORINE PESTICIDES FROM
0.5-g SILICA CARTRIDGES'
Compound
alpha-BHC
gamma-BHC
beta-BHC
Heptachlor
dclta-BHC
Aldrin
Heptachlor epoxide
Endosulfan I
4,4'-DDE
Dieldrin
Endrin
4,4'-DDD
Endosulfan II
4,4'-DDT
Endrin aldehyde
Endosulfan sulfate
4,4'-Methoxychlor
Spiked
at 0.2 \ig per cartridge
Fraction 1
86.3
0
0
104
0
91.8
0
0
96.8
0
0
92.5
0
101
0
0
0
101
16.0
0
103
0
90.8
0
0
99.5
0
0
110
0
107
0
0
0
Fraction 2
35.3
105
113
0
106
0
112
112
0
109
148
0
107
0
82.8
111
113
20.8
101
113
0
107
0
113
116
0
111
151
0
108
0
90.0
118
119
Spiked
at 1.0 p
Fraction 1
76.7
9.2
0
85.6
0
78.1
0
0
89.5
0
0
88.8
0
93.3
0
0
0
72.1
12.1
0
86.4
0
78.1
0
0
84.5
0
0
82.5
0
89.6
0
0
0
ig per cartridge
Fraction 2
34.3
93.9
98.9
0
96.4
0
101
103
0
96.3
152
20.1
95.4
0
74.9
122
108
38.3
90.1
95.6
0
91.6
0
97.3
97.7
0
92.3
142
23.9
92.8
0
72.9
94.7
98.3
Spiked
at 2.0 ]ig per cartridge S
Fraction 1
87.1
15.4
0
95.1
0
85.4
0
0
92.4
0
0
92.8
0
94.2
0
0
0
85.8
16.9
0
93.9
0
84.4
0
0
91.7
0
0
91.6
0
91.8
0
0
0
Q
Fraction 2 ft
35.3
93.8
104
0
94.6
0
103
105
0
93.5
110
19.5
99.4
0
82.9
101
101
36.4
92.1
103
0
94.1
0
100
104
0
92.4
106
22.1
97.0
0
83.2
100
99.8
" Silica cartridges (Supelco lot SP0161) were used; each cartridge was conditioned with 4 mL hexane prior to use. Each
experiment was performed in duplicate. Each cartridge was spiked with 2 mL of a hexane solution containing the organochlorine
pesticides at the concentrations staled above. Fraction 1 was eluted with 5 mL hexane, Fraction 2 with 5 mL hexane with
50 percent diethyl ether. Vacuum manifold used was the Analytichem SPS24.
-------
TABLE 12. PERCENT RECOVERIES AND ELUTION PATTERNS FOR 17 ORGANOCHLORINE PESTICIDES FROM
1-g SILICA CARTRIDGES'
Compound
alpha-BHC
gamma-BHC
beta-BHC
Heptachlor
delta-BHC
Aldrin
Heptachlor epoxide
Endosulfan I
4,4'-DDE
Dicldrin
Endrin
4,4'-DDD
Endosulfan n
4,4'-DDT
Endrin aldehyde
Endosulfan sulfate
4,4'-Mcthoxychlor
Spiked
at 0.2 jig per cartridge
Fraction 1
0
0
0
89.8
0
89.5
0
0
91.0
0
0
0
0
87.5
0
0
0
0
0
0
89.0
0
88.8
0
0
90.3
0
0
0
0
84.5
0
0
0
Fraction 2
92.8
91.5
79.3
0
82.5
0
92.5
101
0
89.3
94.8
84.8
88.5
0
50.0
94.5
91.8
96.3
94.5
81.5
0
84.8
0
94.8
104
0
92.5
98.0
92.0
91.5
0
51.5
97.5
95.0
Spiked
at 1.0 jig per cartridge
Fraction 1
0
0
0
99.1
0
97.9
0
0
102
0
0
13.4
0
100
0
0
0
0
0
0
98.6
0
97.1
0
0
102
0
0
11.6
0
99.4
0
0
0
Fraction 2
99.6
97.2
101
0
96.8
0
101
101
0
95.5
151
95.6
98.8
0
59.3
98.2
104
96.4
94.2
95.9
0
93.5
0
97.2
97.3
0
92.6
145
94.1
95.6
0
59.2
95.3
100
Spiked
at 2.0 |ig per cartridge g
Fraction 1
3.9
0
0
102
0
100
0
0
105
0
0
14.2
0
94.7
0
0
0
8.5
0
0
105
0
102
0
0
109
0
0
24.8
0
98.2
0
0
0
Fraction 2 8
Ul
102
95.0
102
3.5
91.7
2.3
99.7
102
0
91.2
104
94.7
99.4
7.5
67.4
99.1
97.4
105
96.3
106
4.3
95.4
2.9
102
105
0
92.5
107
93.2
102
5.5
70.9
102
100
' Silica cartridges (Supelco lot SP0161) were used; each cartridge was conditioned with 4 mL hexane prior to use. Each experiment
was performed in duplicate. Each cartridge was spiked with 2 mL of a hexane solution containing the organochlorine pesticides at
the concentrations stated above. Fraction 1 was eluted with 5 mL hexane, Fracdon 2 with 5 mL hexane with 50 percent diethyl
ether. Vacuum manifold used was the Analytichcm SPS24.
-------
TABLE 13. PERCENT RECOVERIES AND ELUTION PATTERNS OF 17 ORGANOCHLORINE PESTICIDES FROM
2-g SILICA CARTRIDGES'
Spiked at 0.2 fig per cartridge
Compound
alpha-BHC
gamma-BBC
beta-BHC
Heptachlor
delU-BHC
Aldrin
Heptachlor epoxide
Endosulfanl
4,4'-DDE
Dieldrin
Endrin
4,4'-DDD
Endosulftnn
4.4'-DDT
K> Endrin aldehyde
"^ Endosulfan sulfate
4.4'-Methoxychlor
Fraction 1
0
0
0
21.3
0
76.5
0
0
49.8
0
0
0
0
0
0
0
0
0
0
0
33.0
0
82.8
0
0
64.0
0
0
0
0
0
0
0
0
Fraction 2
93.3
92.5
94.3
85.8
59.3
31.0
95.5
96.3
56.5
93.0
113
97.3
0
95.0
0
0
87.5
91.5
89.8
92.8
75.3
64.8
22.8
94.8
96.0
43.3
92.8
114
98.8
0
95.5
0
0
90.3
Fraction 3
0
0
0
0
32.0
0
0
0
0
0
0
0
83.0
0
0
74.5
0
0
0
0
0
25.5
0
0
0
0
0
0
0
82.8
0
0
76.3
0
Spiked
Fraction 1
0
0
0
22.0
0
66.4
0
0
48.7
0
0
0
0
0
0
0
0
0
0
0
25.4
0
76.1
0
0
55.0
0
0
0
0
0
0
0
0
at 1.0 fig per cartridge
Fraction 2
98.2
98.2
103
90.7
92.0
36.4
104
105
62.4
99.4
139
105
22.5
103
37.2
0
104
93.6
93.9
91.2
88.5
83.9
43.0
97.7
98.8
66.0
95.1
136
100
20.5
97.2
34.6
0
96.7
Fraction 3
0
0
0
0
6.7
0
0
0
0
0
0
0
77.4
0
29.0
88.1
0
0
0
0
0
14.1
0
0
0
0
0
0
0
81.6
0
29.6
90.2
0
Spiked
Fraction 1
0
0
0
11.8
0
39.0
0
0
2.6
0
0
0
0
0
0
0
0
0
0
0
36.7
0
88.2
0
0
68.3
0
0
0
0
0
0
0
0
at 2.0 fig per cartridge g
Fraction 2
103
98.3
108
97.4
89.6
48.9
105
107
78.8
98.6
105
108
15.5
103
39.4
0
103
104
99.3
110
96.3
81.6
39.3
106
110
72.5
99.8
106
109
11.9
105
35.2
0
99.9
Fraction 3 §
ul
0
0
0
0
14.0
0
0
0
0
0
0
0
88.7
0
37.9
97.2
0
0
3.4
0
0
30.9
0
0
0
0
0
0
0
96.4
0
44.6
104
11.8
* Silica cartridges (Supelco lot SP0204) were used; each cartridge was conditioned with 4 mL hexane prior to use. Each experiment was perfonned in duplicate.
Each cartridge was spiked with 2 mL of a hexane solution containing the organochlorine pesticides at the concentrations stated above. Fraction 1 was eluted
with 5 mL hexane. Fraction 2 with 5 mL hexane with 50 percent diethyl ether, and Fraction 3 with 5 mL hexane with 50 percent diethyl ether. Vacuum
manifold used was the Analytichem SPS24.
-------
TABLE 14. ELUTION PATTERNS AND PERCENT RECOVERIES OF 17 ORGANO-
CHLORINE PESTICIDES FROM 0.5-g DIOL CARTRIDGES'
Spiked at 0.2 jig
Compound
alpha-BHC
gamma-BHC
beta-BHC
Heptachlor
dclta-BHC
Aldrin
Heptachlor epoxide
EndosulfanI
4,4'-DDE
Diddrin
Endrin
4,4'-DDD
Endosulfanll
4,4'-DDT
Endrin aldehyde
Endosulfan sulfate
4,4'-Mcthoxychlor
Fraction 1
83.3
79.8
84.0
S8.8
77.5
53.0
81.7
70.3
55.8
79.8
77.0
81.8
80.5
72.0
0
39.8
82.5
83.0
79.8
84.5
58.3
77.0
52.8
80.8
70.0
55.0
79.0
76.3
82.3
80.3
70.8
0
39.5
82.3
per cartridge
Fraction 2
0
0
0
0
0
0
0
0
0
0
0
0
0
0
38.8
58.3
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
36.8
53.3
0
Spiked
at 1.0 ng
Fraction 1
115
115
122
84.8
112
82.5
114
103
87.4
113
113
122
115
106
84.1
111
118
117
113
120
80.9
111
79.2
109
96.0
82.6
109
107
117
114
101
78.2
117
117
per cartridge
Fraction 2
0
0
0
0
0
0
0
0
0
0
0
0
0
0
24.2
12.6
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
24.3
8.6
0
Spiked
at 2.0 Hg
Fraction 1
105
105
105
76.2
102
72.2
101
90.2
74.0
102
98.0
101
102
93.9
12.4
4.9
100
106
99.0
101
81.8
94.5
76.9
100
92.9
78.9
97.9
97.4
101
97.8
94.7
15.4
5.8
97.7
per cartridge g
Fraction 2
-------
TABLE 15. ELUTION PATTERNS AND PERCENT RECOVERIES OF 17 ORGANOCHLORINE PESTICIDES FROM 1-g
DIOL CARTRIDGES'
Spiked at 0.2 p.g per
cartridge
Compound
alpha-BHC
gamma-BHC
bcta-BHC
Hcptachlor
delta-BHC
Aldrin
Hcptachlor epoxide
Endosulfan I
4,4'-DDE
Dieldrin
Endrin
4,4'-DDD
Endosulfan II
4,4'-DDT
Endrin aldehyde
Endosulfan sulfate
4,4'-Methoxychlor
Fraction 1
86.3
80.3
60.5
80.5
52.8
77.3
81.8
85.3
82.5
80.5
81.3
80.3
65.5
81.0
0
0
73.8
97.5
89.8
62.3
92.0
51.8
88.5
94.0
98.0
94.0
92.0
94.0
92.0
66.3
92.8
0
0
80.5
Fraction 2
0
0
0
0
32.7
0
0
0
0
0
0
0
20.8
0
50.3
66.8
0
0
0
0
0
41.5
0
0
0
0
0
0
0
30.3
0
46.5
61.3
0
Spiked at 1.0 ng per
cartridge
Fraction 1
113
107
112
107
101
104
110
114
111
106
111
113
108
110
50.8
26.7
108
95.8
90.0
94.5
90.9
87.1
89.3
93.6
96.1
95.0
90.7
94.2
95.3
91.6
94.4
41.3
23.0
91.6
Fraction 2
0
4.8
0
0
8.9
0
0
0
0
0
0
0
0
0
54.0
91.0
0
0
4.7
0
0
8.0
0
0
0
0
0
0
0
0
0
55.9
93.0
0
, — • -•••- -K
CM
g
Spiked at 2.0 ug per cartridge a
Fraction 1
107
102
97.8
103
84.5
99.7
105
104
100
102
97.2
104
94.9
102
15.8
0
97.1
107
101
93.5
104
78.1
102
104
103
101
100
97.6
102
89.7
100
11.7
0
93.1
Fraction 2
0
4.1
15.4
0
26.1
0
0
0
0
0
0
0
17.5
0
75.0
86.8
0
0
4.6
20.2
0
5.4
0
0
0
0
0
0
0
23.8
0
71.7
81.8
10.9
Fraction 3
0
0
0
0
0
0
0
0
0
0
0
0
0
0
20.9
21.4
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
21.1
24.4
0
* Diol cartridges (Supelco lot SP0216) were used; each cartridge was conditioned with 4 mL hexane with 10 percent acetone prior to use.
Each experiment was performed in duplicate. Each cartridge was spiked with 2 mL of a hexane solution at the concentrations stated
above. Fraction 1, 2, and 3 were each eluted with 5 mL hexane with 10 percent acetone. Vacuum manifold used was the Analytichem
SPS24.
-------
TABLE 16. ELUTION PATTERNS AND PERCENT RECOVERIES OF 17 ORGANO-
CHLORINE PESTICIDES FROM 2-g DIOL CARTRIDGES"
Compound
alpha-BHC
gamma-BHC
beta-BHC
Heptachlor
delta-BHC
Aldrin
Heptachlor epoxide
Endosulfan I
4,4'-DDE
Dieldrin
Endrin
4,4'-DDD
Endosulfan II
4,4'-DDT
Endrin aldehyde
Endosulfan sulfate
4,4 '-Mcthoxychlor
Fraction 1
0
0
0
96.0
0
96.0
0
60.0
97.5
0
0
0
0
30.0
0
0
0
0
0
0
99.8
0
82.8
0
49.0
83.0
0
0
0
0
0
0
0
0
Spiked
at 0.2 |ig per cartridge
Fraction 2
97.5
88.5
0
0
0
0
88.5
40.5
0
90.0
85.5
93.0
0
67.5
0
0
0
97.5
87.0
0
0
0
0
91.5
48.0
0
91.5
90.0
93.0
0
73.5
0
0
0
Fraction 3
0
0
75.0
0
0
0
0
0
0
0
0
0
70.5
0
0
0
77.0
0
15.0
58.5
0
0
0
0
0
0
0
0
0
45.0
0
0
0
78.0
Fraction 4
0
0
0
0
73.5
0
0
0
0
0
0
0
27.0
. 0
0
0
0
0
0
0
0
61.5
0
0
0
0
0
0
0
49.5
0
0
0
0
Spiked at 1.0 ^ig
Fraction 1
93.1
31.1
0
107
0
108
99.4
105
110
95.6
103
65.5
0
103
0
0
0
81.4
29.3
0
99.7
0
100
90.0
99.3
104
84.9
94.0
55.0
0
95.4
0
0
0
per cartridge
Fraction 2
30.1
88.0
105
0
96.6
0
16.6
7.2
0
15.6
9.7
60.9
102
8.6
20.4
8.1
102
30.7
70.6
81.3
0
76.2
0
15.3
0
0
15.5
8.5
51.0
78.8
7.6
11.6
0
76.7
(continued)
' Diol cartridges (Supelco lot SP0216) were used; each cartridge was conditioned with 4 mL hexane with 10 percent acetone
prior to use. Each experiment was performed in duplicate. Each cartridge was spiked with 2 mL of a hexane solution at the
concentrations stated above. Fractions 1, 2, 3, and 4 were each eluted with 5 mL hexane with 10 percent acetone. Vacuum
manifold used was the Analytichem SPS24.
-------
TABLE 16. (Concluded)'
Spiked at 1.0 Hg per cartridge
Compound
alpha-BHC
gamma-BBC
beta-BHC
Heptachlor
dclta-BHC
Aldrin
Heptachlor cpoxidc
Endosulfan I
4,4'-DDE
Dieldrin
Endrin
4,4'-DDD
Endosulfan II
4,4'-DDT
Endrin aldehyde
Endosulfan sulfate
4,4'-Methoxychk>r
Fraction 3
0
0
0
0
0
0
0
0
0
0
0
0
0
0
64.3
88.9
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
61.4
84.8
0
Fraction 4
0
0
0
0
0
0
0
0
0
0
0
0
0
0
12.8
10.8
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
17.4
18.6
0
Fraction 1
11.5
0
0
105
0
104
37.8
84.0
103
25.7
45.8
0
0
62.6
0
4.2
0
9.2
0
0
108
0
108
30.3
84.1
106
18.4
37.4
0
0
59.3
0
0
0
Spiked
at 2.0 itg per cartridge
Fraction 2
101
98.8
43.4
5.8
8.2
3.4
85.4
39.6
4.7
86.8
73.1
99.1
36.1
61.6
7.5
0
84.1
102
99.9
28.1
5.6
3.8
3.6
91.8
44.4
4.4
91.2
80.3
99.4
19.5
67.3
7.9
0
77.2
Fraction 3
0
4.0
68.7
0
82.9
0
0
0
0
0
0
0
75.3
0
0
0
19.9
0
5.2
83.0
0
77.6
0
0
0
0
0
0
0
86.6
0
0
0
29.5
R
CM
P
Fraction 4 |
0
0
0
0
15.2
0
0
0
0
0
0
0
4.0
0
0
0
0
0
0
0
0
30.0
0
0
0
0
0
0
7.5
0
0
0
0
0
' Diol cartridges (Supelco lot SP0216) were used; each cartridge was conditioned with 4 mL hexane with 10 percent acetone
prior to use. Each experiment was performed in duplicate. Each cartridge was spiked with 2 mL of a hexane solution at the
concentrations stated above. Fractions 1,2, 3, and 4 were each eluted with 5 mL hexane with 10 percent acetone. Vacuum
manifold used was the Analytichem SPS24.
-------
to
VO
TABLE 17. ELUTION PATTERNS AND PERCENT RECOVERIES OF 17 ORGANOCHLORINE PESTICIDES AND
AROCLOR 1260 FROM 1-g DIOL CARTRIDGES
Spiked with organochlorine pesticides at 0.2 \ig
and Aroclor 1260 at 80 \ig per cartridge
Compound
Aroclor 1260
alpha-BHC
gamma-BHC
bcta-BHC
Hcptachlor
delta-BHC
Aldrin
Heptachlor cpoxidc
EndosulfanI
4,4'-DDE
Dieldrin
Endrin
4,4'-DDD
Endosulfann
4,4'-DDT
Endrin aldehyde
Endosulfan sulfate
4,4'-Methoxychlor
Fraction 1
(3 mL hexane)
90
0
0
0
112
0
116
0
58.5
124
0
0
0
0
>1001
0
0
0
Fraction 2
(5 mL hexane
with 10 percent
acetone)
10
93
105
103
0
97.3
0
97.3
71.5
0
108
>100"
99.5
>100t
0
39.5
29.2
>100*
Fraction 3
(5 mL hexane
with 10 percent
acetone)
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
60.5
70.8
0
Spiked with organochlorine pesticides at 0.2 \ig g
and Aroclor 1260 at 2 \Lg per cartridge Q
in
Fraction 1
(3 mL hexane)
100
0
0
0
102
0
110
0
59.2
123
0
0
0
0
100
0
0
0
Fraction 2
(5 mL hexane
with 10 percent
acetone)
0
106
96
100
0
113
0
112
93.2
0
112
100
100
100
0
35.0
14.0
100
ID
Fraction 3
(5 mL hexane
with 10 percent
acetone)
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
65.0
86.0
0
'Cannot be quantitated accurately because of interference from Aroclor 1260.
-------
solutions were then subjected to the silica or the diol cartridge cleanup procedure to establish
if any changes occurred in the target compound elution pattern and in their recoveries
caused by matrix interferents (Tables 18 and 19). These interferents were selected because they
mimic typical background contamination in certain environmental sample matrices that could
also be contaminated with the target compounds. For example, corn oil would be representative
of fatty acid triglycerides, and diesel hydrocarbons of petroleum hydrocarbons. The data
presented in Tables 18 and 19 indicate that neither the corn oil nor the diesel hydrocarbons
affected the elution patterns of the 17 organochlorine pesticides. Elemental sulfur, if present,
is eluted from the silica cartridge with 5 mL hexane and will interfere only with the gas
chromatographic analysis of heptachlor and aldrin on the DB-1701 column (Figure 4). 4,4'-
DDE and 4,4'-DDT also elute in Fraction 1, however, they can be quantified without any
difficulty on any of the two columns. The remainder of the 17 organochlorine pesticides are
retained on the silica cartridge and then eluted with hexane with 50 percent diethyl ether. The
diol cartridge procedure was also evaluated to determine whether elemental sulfur, if present,
can be separated from the organochlorine pesticides. We found that when the cartridge is
eluted with hexane with 10 percent acetone, the elemental sulfur elutes from the cartridge
together with the organochlorine pesticides and will interfere with the gas chromatographic
analysis on the DB-1701 column of compounds 1 through 6 in Table 1 (Figure 5). It is possible
that elemental sulfur could be removed as in the case of the silica cartridge, however, we have
not tested this yet.
5.2 PHTHALATE ESTERS
Florisil and alumina SPE cartridges were evaluated for their use in phthalate ester
analysis. These cartridges were chosen because the current SW-846 Method 8060 recommends
use of either Florisil (Method 3620) or alumina (Method 3610) for cleanup of sample extracts
containing phthalate esters. In Method 3620, Florisil (60/80 mesh) is activated for 16 hours at
140°C and then deactivated with water (3 percent by weight). The charged Florisil column is
eluted with hexane (40 mL) to remove interfering compounds; phthalate esters are then
recovered with 100 mL hexane with 20 percent diethyl ether. In Method 3610, neutral alumina,
activity Super I, W206 series, is activated for 16 hours at 400°C and the phthalate esters are
recovered with 140 mL of hexane with 20 percent diethyl ether.
We have evaluated both methods with hexane solutions containing the 16 phthalate
esters listed in Table 2. The percent recoveries of the 16 compounds are presented elsewhere
(5). Alumina cleanup is preferred over the Florisil cleanup since it allows recovery of all target
compounds by elution with hexane with 20 percent diethyl ether. When Florisil cleanup was
used, BMEP, BEEP, and BBEP could not be recovered at all, and DMP and DEP gave
recoveries of only 40 and 57 percent, respectively.
To improve the recoveries of the five phthalate esters mentioned above, we have taken
Florisil and alumina SPE cartridges of 0.5-g, 1.0-g, and 2-g size, charged them with the target
compounds and interferents, and eluted them with hexane with 10 percent acetone (for Florisil)
or hexane with 20 percent acetone (for alumina). We had at first attempted to elute the
phthalate esters from the alumina cartridge with hexane with 20 percent diethyl ether. Since
none of the phthalate esters was recovered after 10 mL solvent passed through the cartridge, we
changed the eluting solvent to hexane with 10 percent acetone and later to hexane with
20 percent acetone to improve the recovery of BMEP, BEEP and BBEP. The results of these
experiments are summarized in Tables 20, 21, and 22.
30
-------
TABLE 18. PERCENT RECOVERIES AND ELUTION PATTERNS OF 17 ORGANOCHLORINE PESTICIDES FROM
1-g SILICA CARTRIDGES IN THE PRESENCE OF CORN OIL AND DIESEL HYDROCARBONS'
Corn oil as
Compound
alpha-BHC
gamma-BHC
beta-BHC
Heptachlor
delta-BHC
Aldrin
Heptacnlor epoxide
Endosulfan I
4,4'-DDE
Dieldrin
Endrin
4,4'-DDD
Endosulfan II
4,4'-DDT
Endrin aldehyde
Endosulfan sulfate
4,4'-Methoxychlor
Fraction 1
0
0
0
119
0
119
0
0
113
0
0
0
0
103
0
0
0
0
0
0
123
0
120
0
0
120
0
0
13.3
0
114
0
0
0
interferents
Fraction 2
121
124
114
0
115
0
123
121
0
117
143
109
113
0
66.7
108
110
119
122
111
0
112
0
121
118
0
114
142
106
110
0
64.7
105
107
Fraction 3
0
0
0
0
0
0
0
0
0
0
0
0
0
0
26.9
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
31.8
0
0
Diesel hydrocarbons as interferents
Fraction 1
0
0
0
115
0
112
0
0
120
0
0
14.2
0
115
0
0
0
0
0
0
113
0
110
0
0
118
0
0
16.5
0
109
0
0
0
Fraction 2
115
118
106
0
108
0
118
117
0
111
150
106
109
0
55.4
98.2
105
116
120
108
0
111
0
120
119
0
114
156
108
111
0
62.5
103
107
S
CM
£
Fraction 3 «
0
0
0
0
0
0
0
0
0
0
0
0
0
0
31.0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
31.6
0
0
' Silica cartridges (Supelco lot SP0161) were used; each cartridge was conditioned with 4 mL hexane prior to use. Each experiment was
performed in duplicate. Each cartridge was spiked with 2 mL of a hexane solution containing the organochlorine pesticides at 0.5 u,g/
mL, the com oil at 500 u.g/mL, and the diesel hydrocarbons at 1000 u,g/mL. Fraction 1 was eluted with 5 mL hexane, Fraction 2 with 5
mL hexane with 50 percent diethyl ether, and Fraction 3 with 5 mL hexane with 50 percent diethyl ether. Vacuum manifold used was
the Analytichem SPS24.
-------
10
TABLE 19. PERCENT RECOVERIES AND ELUTION PATTERNS OF 17 ORGANOCHLORINE PESTICIDES FROM
1-g DIOL CARTRIDGES IN THE PRESENCE OF CORN OIL AND DIESEL HYDROCARBONS1
Corn oil as interferents
Compound
alpha-BHC
gamma-BHC
beta-BHC
Heptachlor
delta-BHC
Aldrin
Heptachlor epoxide
EndosulfanI
4,4'-DDE
Dicldrin
Endrin
4,4'-DDD
Endosulfan II
4,4'-DDT
Endrin aldehyde
Endosulfan sulfate
4l4'-Methoxychk>r
Fraction 1
121
120
108
120
108
115
120
121
115
118
111
112
111
110
28.6
0
100
119
118
106
119
107
113
116
120
115 '
116
111
110
108
110
26.8
0
99.0
Fraction 2
0
0
0
0
0
0
0
0
0
0
0
0
0
0
73.0
102
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
76.8
108
0
Fraction 3
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Diesel hydrocarbons as interferents
Fraction 1
115
116
102
117
108
111
120
120
116
118
116
115
114
114
22.8
0
98.6
116
118
104
119
110
117
122
124
122
120
120
118
115
117
0
0
100
Fraction 2
0
0
0
0
0
0
0
0
0
0
0
0
0
0
69.8
111
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
42.6
107
0
£
e
Fraction 3 «
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
" Diol cartridges (Supelco lot SP0206) were used; each cartridge was condidoned with 4 mL hexane with 10 percent acetone prior to use.
Each experiment was performed in duplicate. Each cartridge was spiked with 2 mL of a hexane solution containing the organochlorine
pesticides at 0.5 JigAnL, the com oil at 500 Hg/mL, and the diesel hydrocarbons at 1000 jig/mL. Fractions 1,2, and 3 were each eluted
with 5 mL hexane with 10 percent acetone in hexane. Vacuum manifold used was the Analytichem SPS24.
-------
T
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10
z
E:
in
o
iii
M
ATTEN: 32
-rrsT^pr
'
.it llfc-fc—
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III II
1 1
r
1 1
r*>
o
\
Z
\
c
O
• UJ
ON
a
bin
urn
a.
in
a: uil
DB-608
DB-1701
Ill
in
DB-608
\*i
o
1-
H
^
t .
2
•-» ^
z in
\
E
O ••
0
• UJ
<& I\J
a
uirM
UJIO
a.
in
i- z
G>
rr
r
-
LA
in
in-
ata
•u
OD <
iriFi
P.
inrg r^
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&
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.
^1"
^-1
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-
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- -
r
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•O
fM
DB-1701
Figure 4. GC/ECD chromatograms of a Method 8081 organochlorine pesticide standard
containing elemental sulfur, passed through a silica cartridge; Fraction 1 (left),
Fraction 2 (right). The GC operating conditions are given in Table 1
-------
OJ
DB-608
O
-------
TABLE 20. ELUTION PATTERNS AND PERCENT RECOVERIES OF THE PHTHALATE
ESTERS FROM THE FLORISIL CARTRIDGES USING HEXANE WITH
10 PERCENT ACETONE"
O*
0.5-g cartridge
Compound
DMP
DEP
D1BP
DBP
BMPP
BMEP*
DAP
BEEP
HEHP
DHP
BBP
BBEP
DEHP
DCP
OOP
DNP
40-Wjiplk*
Fraction 1
98.9
108
109
104
106
16.0
107
96.6
99.6
105
108
113
111
91.4
120
118
101
113
106
107
114
IS.6
111
97.6
98.4
109
109
117
111
81.6
114
118
80-/1R spike
Fraction 1
81.2
91.3
92.8
87.4
98.2
11.9
94.R
74.7
75.6
91.0
84.1
98.5
92.1
62.9
102
101
KO.K
9X1
91.7
88.5
95.9
I4.R
91.5
69.3
75.9
87.6
82.3
94.3
87.6
61.7
93.2
92.2
I20-/JR spike
Fraction 1
73.9
83.7
87.H
80.1
86.4
10.7
82.7
65.8
65.3
78.6
67.5
83.2
76.5
53.5
83.3
83.1
76.4
85.3
91.8
83.1
90.2
IS.')
87.9
71.6
68.9
86.0
71.3
91.4
84.5
57.0
95.4
95.9
40-0R spike
Fraction 1
91.1
99.5
94.9
100
112
c
96.8
96.0
101
99.4
99.8
105
95.6
97.0
99.9
111
87.6
95.1
KK.6
105
99.1
*
92.1
91.1
90.8
94.1
97.3
89.9
87.4
84.1
94.3
988
l-g cartridge
KO-W5 spike
Fraction 1
42.1
81.2
8K.7
89.1
95.4
•
89.4
d
70.6
88.6
80.4
95.3
68.0
62.0
98.1
98.1
57.7
87.3
')2.1
87.4
"4 1
T
92.5
d
70.2
87.9
82.8
102
74.7
53.7
97.9
100
I20.pi> «pike
Fraction 1
28.5
78.6
91)6
87.9
92.5
C
88.1
4
66.1
85.1
70.1
97.4
47.1
59.0
98.5
98.3
35.7
76.5
8K.1
85.8
89.2
'
85.6
d
63.9
82.5
69.5
93.5
50.2
48.0
93.0
94.8
40-fig spike
Fraction 1
70.9
III
114
108
115
•
113
d
83.9
106
109
118
111
69.6
114
118
95.3
94.0
103
108
116
c
106
d
93.8
103
104
112
65.8
720
115
115
2-g cartridge
HO-HR spike
Fraction 1
37.1
100
92.2
91.4
94.8
f
91.8
d
68.9
86.4
83.2
98.3
82.9
59.9
103
101
30.5
101
92.8
92.4
95.8
•
92.3
d
84.3
90.9
93.9
95.9
84.4
57.3
99.4
99.3
120-HR spike
Fraction 1
63.6
107
K6.9
82.5
105
'
83.4
4
77.8
80.6
101
94.1
81.5
72.2
97.3
92.8
72.9
107
86.0
80.9
98.5
•
82.6
tf
77.5
78.3
97.2
87.0
77.6
59.9
86.9
88.5
* Each cartridge wa» preconditioned with 4 mL hexane prior to use Each experiment was performed in duplicate. Fraction 1 was eluted with 5 mL hexane with
10 percent acetone; Fraction 2 with 5 mL hexane with 10 percent acetone A third fraction was collected from the 2-g cartridge by elution with 5 mL hexane with
10 percent acetone.
* Additional BMEP wai recovered from the 0.5-g Fkwisil cartridge by editing the cartridge with an additional 5 mL hexane with 10 percent acetone (Fraction 2). The
recoveries in Fraction 2 were 70.3 and 71.3 percent lor the 40-|ig spike. 55.4 and 54.3 percent for the KO-fig spike, 53.4 and 54.1 percent for the 120-pg spike.
' Compound not recovered in any of the three fractions.
' BEEP phthalate was recovered by editing the cartridge with an additional 5 mL hexane with of 10 percent acetone. Total recoveries were 75.1 and 79.3 percent for
the 80*flg spike (l-gcartridge), 57.3 and 56.5 percent for the !20-/tg spike (l-g cartridge), 94.6 percent for the 40-(lg spike (2-g cartridge), 55.4 and 62.0 percent for
the 80-pg spike (2-g cartridge), 70.2 and 79.0 percent for the 120-pg spike (2-g cartridge).
-------
TABLE 21. ELUTION PATTERNS AND PERCENT RECOVERIES OF THE PHTHALATE
ESTERS FROM ALUMINA CARTRIDGES USING HEXANE WITH 10 PERCENT
AND 20 PERCENT ACETONE'
Hexane with 10 percent acetone
Compound
DMP
DEP
DIBP
DBP
BMPP
BMEP
DAP
BEEP
HEHP
DHP
BBP
BBEP
DEHP
DCP
OOP
DNP
Fraction
(5mL)
78.6
101
94.0
101
86.4
0
63.6
16.6
68.5
99.9
93.8
75.4
99.1
73.3
97.9
89.5
1
65.6
84.5
75.8
88.1
37.0
0
57.3
19.6
56.9
89.3
89.6
66.3
88.3
67.0
120
113
Fraction
(5mL)
47.9
0
0
0
0
31.5
0
109
0
0
10.3
50.2
0
0
0
0
2
28.8
0
0
0
0
40.3
0
102
0
0
5.4
47.6
0
0
0
0
Hexane with 20 percent acetone
Fraction
(5mL)
101
103
105
109
104
66.6
106
121
103
112
106
114
102
99.0
118
93.5
1
102
103
104
107
102
61.6
100
102
99.3
105
100
103
83.1
90.5
107
101
Fraction
(5mL)
0
0
0
0
0
38.8
0
0
0
0
0
0
0
0
0
0
2
0
0
0
0
0
34.8
0
0
0
0
0
0
0
0
0
0
• 1-g alumina cartridges (Supelco lot SP 0214) were used; each cartridge was preconditioned with 4 mL hexane prior
to use. Each experiment was performed in duplicate; the amount spiked was 40 jig per component per cartridge
(2 mL of 20 pg/mL in hexane).
-------
TABLE 22. ELUTION PATTERNS AND PERCENT RECOVERIES OF THE PHTHALATE
ESTERS FROM THE ALUMINA CARTRIDGES OF VARIOUS SIZES USING
HEXANE WITH 20 PERCENT ACETONE"
0.5-g cartridge
COMpMUM FnClMNI 1
DMP
DEP
DIBP
DBP
BMPP
BMEP
DAP
BEEP
HEHP
DHP
BBP
BBBP
DEHP
DCP
OOP
DNP
106
III
92.5
101
98
98.8
103
107
102
10!
113
86.4
112
100
84.3
77.1
IOK
112
94.3
103
96.4
104
KM
110
104
100
116
78.5
112
102
74.3
66.2
H0-/ig spike
Fraction 1
67.H
76.2
79.8
83.8
81.4
76.0
83.6
80.9
68.3
81.5
59.2
83.0
77.3
63.9
79.6
80.7
72.6
78.9
80.6
86.7
82.6
79.4
83.2
84.6
72.0
87.4
61.9
91.1
87.8
62.3
90.5
895
I20-/ig spike
Fraction 1
69.5
73.1
116
91.3
too
87.7
993
95.2
78.1
101
62.0
117
96.6
73.5
103
96.4
71.3
75.3
115
89.6
109
88.8
98.7
94.5
69.8
85.4
60.5
113
913
72.6
101
94.7
40-flg spike
Fraction 1
108
139
77.5
101
75.1
87.1
92.4
96.5
81.1
116
103
88.1
99.4
99.3
93.3
106
117
148
85.4
109
90.4
93.8
101
105
104
126
110
92.5
107
105
108
114
I.O-g cartridge
80-pg spike
Fraction 1
100
106
93.8
109
92.3
92.2
103
97.7
90.3
94.9
99.1
99.4
100
92.4
101
103
92.1
125
108
121
107
101
116
109
110
106
106
no
113
106
113
114
120-/lg spike
Fraction 1
115
126
96.9
103
83.3
90.3
95.0
103
87.4
118
104
104
93.5
90.5
103
113
113
127 -
94.0
101
81.5
885
93.0
96.6
86.2
116
103
103
92.0
89.9
102
no
40-pg spike
Fraction 1
98.6
106
84.6
95.4
81.8
k
82.4
81.6'
74.9
95.5
89.3
73.3
85.6
57.4
85.6
88.9
93.8
108
86.5
94.6
80.3
k
84.4
67.9"
78.8
97.8
91.0
73.9
87.0
59.1
86.5
91.5
2.0-g cartridge
80-Mg spike
Fraction 1
92.3
105
119
108
101
k
98.6
76.9"
94.1
87.8
96.8
101
99.1
82.1
101
100
73.2
102
no
103
98.1
k
94.9
55.8'
87.9
81.6
92.8
96.5
93.1
71.1
97.1
96.1
I20-/1R spike
Fraction 1
K4.I
112
W.8
98.2
81.5
k
87.7
45.6'
78.5
101
94.5
87.3
90.2
60.7
93.1
102
93.0
104
100
92.8
78.8
b
83.3
70.3'
74.2
93.7
88.4
79.5
85.6
57.5
85.9
92.9
•J. T. Baker alumina cartridges: Lot B41714 for 0.5-g size. Lot B12505 for I-g size, and Lot B41714 for 2-g size. Each cartridge was preconditioned with 4 mL hexane prior to use.
Each experiment was performed in duplicate. Fraction 1 was eluted with 5 mL hexane with 20 percent acetone; Fraction 2 with 5 mL hexane with 20 percent acetone. A third
fraction was collected from the 2-g cartridge by elution with 5 mL hexane with 20 percent acetone,
*BMEP was recovered from the 2-g alumina cartridge by eluting the cartridge with two additional 5-mL portions of hexane with 20 percent acetone (Fractions 2 and 3). The
recoveries in Fraction 2 were 77.6 and 50.9 percent (40-pg spike), 57.8 and 46.2 percent (80-pg spike), and 26.3 and 61.5 percent (I20-/lg spike). The recoveries in Fraction 3 were
38.1 percent (40-
-------
The data shown in Table 20 indicate that all but two phthalate esters can be recovered
from a 0.5-g or a 1-g Florisil cartridge with 5 mL hexane with 10 percent acetone (Fraction 1)
and from a 2-g cartridge with 10 mL hexane with 10 percent acetone (no phthalate esters were
recovered in Fraction 1, therefore an additional fraction had to be collected). The two phthalate
esters that could not be recovered are BMEP and BEEP. When working with the 0.5-g Florisil
cartridge, these two phthalate esters were recovered almost quantitatively by eluting the cartridge
with an additional 5 mL hexane with 10 percent acetone; however, they could not be recovered
from either the 1-g or the 2-g Florisil cartridge under similar conditions.
The alumina cartridge was first eluted with 5 mL hexane with 10 percent acetone
(Table 21). Since BMEP was not recovered at all and BEEP had recoveries <20 percent in
Fraction 1, the cartridge was eluted with an additional 5 mL hexane with 10 percent acetone.
In addition, we also eluted the cartridge with hexane with 20 percent acetone. This allowed
quantitative recovery of 15 phthalate esters in Fraction 1. The only compound that had recovery
under 70 percent was BMEP (Table 21). The alumina cartridge procedure using hexane with
20 percent acetone was further evaluated with cartridges of 0.5 g, 1 g, and 2 g in size, charged
with the 16 phthalate esters at three spiking levels (Table 22). The results indicate that the
16 phthalate esters were recovered quantitatively with the exception of BMEP from the 2-g
cartridge.
Matrix interferents such as corn oil, diesel hydrocarbons, elemental sulfur, and the
organochlorine pesticides listed in SW-846 Method 8081 were added to hexane solutions
containing the 16 phthalate esters at known concentrations, and the hexane solutions were then
subjected to the Florisil or alumina cartridge cleanup procedure (Table 23). These interferents
were selected because they mimic typical background contamination in certain environmental
sample matrices that could also be contaminated with the target compounds. For example, corn
oil would be representative of fatty acid triglycerides, diesel hydrocarbons of petroleum
hydrocarbons, and organochlorine pesticides of compounds of environmental significance that
would be expected to behave in the same way as the target analytes investigated in this study.
The data presented in Table 23 indicate that neither the corn oil nor the diesel hydrocarbons
affected the elution patterns or the recoveries of the 16 phthalate esters from the Florisil or the
alumina cartridge. Corn oil was also removed from the Florisil cartridge with hexane with
10 percent acetone. Fortunately, its presence does not seem to affect the GC determination of
the 16 phthalate esters. This statement is true only for corn oil concentrations below 0.2 mg/mL
of solvent (or 1 mg per cartridge) because this is the maximum concentration we used. Diesel
hydrocarbons do not seem to cause problems with the GC quantification of the phthalate esters
because the GC detector is transparent to aliphatic hydrocarbons. Elemental sulfur, if present,
is eluted from the Florisil cartridge with hexane with 10 percent acetone (Figure 6) and from
the alumina cartridge with hexane with 20 percent acetone (Figure 7). Therefore, extracts that
are known to contain elemental sulfur should be subjected to sulfur cleanup (Method 3660) prior
to Florisil or alumina cartridge cleanup. Separation of the organochlorine pesticides will be
described later in this section.
The effect of interferents when the Florisil cartridges were eluted with hexane/diethyl
ether (1:1) is presented in Table 24. Corn oil and the diesel hydrocarbons do not seem to
interfere with the determination of the 16 phthalate esters, except for DAP that could not be
quantified because of interference and BMEP and BEEP that had low recoveries.
The organochlorine pesticides overlapped with the phthalate esters when the GC
analysis was performed on the DB-5 fused-silica capillary column; they have to be separated
prior to the GC analysis. Hexane with 50 percent diethyl ether did not give adequate recoveries
for 8 of the 16 phthalate esters (Table 24), but use of hexane with 20 percent methylene chloride
followed by hexane with 10 percent acetone gave quantitative recoveries for 14 of the
16 phthalate esters (Table 25).
38
-------
TABLE 23. PERCENT RECOVERIES OF THE PHTHALATE ESTERS FROM FLORISIL
AND ALUMINA CARTRIDGES WHEN INTERFERENTS WERE PRESENT"
VO
Compound
Florisil cartridge (Fraclion 1)
Alumina cartridge (Fraction 1)
Corn oil
(1000 pg per cartridge)
Diesel
hydrocarbons
(2000 Hf> per cartridge)
Corn oil
(I()(M) /ig per cartridge)
Diesel
hydrocarbons
(2000 /ig per cartridge)
DMP
DEP
DIBP
DBF
BMP
BMEP*
DAP
BEEP
HEHP
DHP
BBP
BBEP
DEHP
DCP
OOP
DNP
119
133
101
111
104
k
96.6
53.3
89.8
108
106
104
99.9
81.4
109
114
123
133
104
111
104
b
96.8
64.6
91.2
106
107
104
99.4
81.2
108
114
106
123
111
110
93.2
b
98.8
43.7
87.1
103
102
98.8
92.1
68.2
102
107
111
129
107
114
95.7
b
98.8
32.3
86.6
104
104
100
94.6
68.2
103
111
105
120
88.8
92.4
61.2
81.4
82.7
70.9
74.3
99.8
93.8
87.8
83.3
81.8
93.1
98.5
104
119
87.7
91.1
63.1
81.8
83.1
71.8
82.9
98.9
92.6
87.8
83.1
81.3
92.7
99.2
92.5
92.5
82.8
88.7
69.8
74.1
74.9
66.0
71.1
90.3
84.6
88.3
72.6
72.0
80.9
86.4
94.4
94.4
85.8
90.4
71.0
75.8
76.9
67.9
73.1
91.5
87.3
81.6
74.6
73.8
82.7
88.3
* 1-g cartridges were used for this experiment. Each cartridge was preconditioned with 4 mL hexane. Each experiment was performed in
duplicate. The Florisil cartridge was eluted with two 5-mL portions of hexane with 10 percent acetone (Fractions 1 and 2). The alumina
cartridge was eluted with two 5-mL portions of hexane with 20 percent acetone (Fractions 1 and 2).
* BMEP was recovered from the Florisil cartridge. The recoveries in Fraction 2 were 81.9 and 95.6 percent when corn oil was present as
interferent and 71.5 and 62.3 percent when diesel hydrocarbons were the interferents.
' Additional BEEP was recovered from the Florisil cartridge in Fraction 2. The recoveries in Fraction 2 were 41.6 and 31.7 percent when
corn oil was present as interferent, and 56.8 and 63.4 percent when diesel hydrocarbons were the interferents.
-------
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-------
TABLE 24. ELUTION PATTERNS AND PERCENT RECOVERIES OF PHTHALATE ESTERS FROM FLORISIL
CARTRIDGES WITH HEXANE WITH 50 PERCENT DIETHYL ETHER'
Fraction 1
No
Compound
DMP
DEP
DIBP
DBP
BMPP
BMEP
DAP
BEEP
HEHP
DHP
BBP
BBEP
.. DEHP
8 DCP
OOP
DNP
interferents
94
%
122
116
108
2.6
95
8.9
112
98
111
65
95
98
106
90
94
95
119
114
109
96
101
99
104
98
117
97
103
101
109
91
With corn
oil
78
84
122
b
103
38
b
7.8
127
128
122
78
89
118
114
KO
82
93
115
105
87
19
103
44
116
106
117
90
83
86
80
72
With diescl
hydrocarbons
116
74
105
124
109
128
b
55
88
107
118
103
85
114
114
KM
108
70
97
113
%
109
0
48
81
103
112
112
78
104
107
•>5
With
organochlorine
pesticides
93
103
118
h
b
b
b
14
86
b
b
b
91
100
108
94
91
98
III
b
b
b
b
58
83
b
b
b
86
96
102
90
No
interferenls
<5
<5
<5
<5
<5
32
<5
51
<5
<5
<5
27
<5
<5
<5
<5
<5
<5
<5
<5
<5
<5
<5
<5
<5
<5
<5
<5
<5
<5
<5
<5
With
Fraction 2
corn
oil
<5
10
<5
<5
<5
<5
<5
66
11
6.0
<5
25
<5
<5
<5
<5
<5
<5
<5
<5
<5
20
<5
54
8.2
<5
<5
10
<5
<5
<5
<5
With
diesel
hydrocarbons
<5
7.6
<5
<5
<5
32
6.1
62
8.2
<5
<5
9.6
<5
<5
<5
<5
<5
<5
<5
<5
<5
22
7.2
58
6.0
<5
<5
10
<5
<5
<5
<5
With
organochlorine
pesticides
<5
6.2
19
<5
60
103
74
53
<5
17
6.8
58
<5
<5
<5
<5
<5
6.4
22
<5
72
128
87
54
<5
20
7.4
69
<5
<5
<5
<5
'Florisil cartridges (I g) were used. Fraction 1 was edited with 5 mL hexane with 50 percent diethyl ether and Fraction 2 with an additional 5 mL hexane with
50 percent dielhyl ether. Final volume of each fraction was 5 mL The phthalate esters were spiked at 2,500 ng per cartridge.
'Not able to determine because of interference.
-------
TABLE 25. RESULTS OF THE FLORISIL CARTRIDGE CLEANUP EVALUATION
STUDY (PHTHALATE ESTER STANDARDS ONLY; ELUTION WITH
HEXANE/METHYLENE CHLORIDE (4:1) AND HEXANE/ACETONE (9:1))
Percent recovery
Compound
DMP
DEP
DIBP
DBF
BMPP
BMEP
DAP
BEEP
HEHP
DHP
BBP
BBEP
DEHP
DCP
DOP
DNP
8712-013-10
Fraction
I n
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
68.0
87.7
107
103
116
36.0
75.0
78.3
118
72.0
91.0
113
107a
106
125
100
8712-013-11
Fraction
I H
0
0
0
23.5
0
0
0
0
0
0
0
0
0
0
0
0
121
90.7
140
129
123
39.1
130
99.0
134
61.0
102
188
113'
109
131
112
8712-013-12
Fraction
I II
0
0
0
0
0
0
6.6
0
0
0
0
0
0
0
0
0
201
86.3
108
131
130
20.7
76.0
69.0
127
53.0
102
103
110a
102
114
94.7
aNot corrected for method blank; if corrected, recovery would
become 0. Study conducted in the presence of OCPs indicated
that the OCPs are eluted in Fraction I.
43
-------
Additional experiments were performed in order to develop a procedure that allowed
the determination of the phthalate esters in the presence of the organochlorine pesticides. The
experimental design is presented in Table 26. Tables 27 and 28 present the recovery data and
elution patterns of the 16 phthalate esters when the cartridges were eluted with hexane/
methylene chloride and then hexane/ethyl acetate. In absence of the organochlorine pesticides,
the phthalate esters were recovered from the Florisil cartridge with hexane with 10 percent ethyl
acetate. However only BMPP, HEHP, BBP, DCP, DOP, and DNP had satisfactory recoveries
(recovery > 70 percent). The remainder of the phthalate esters were either not recovered at all
(e.g., BBEP) or had very low recoveries. When the organochlorine pesticides were spiked
together with the phthalate esters on the Florisil cartridges and the cartridges were eluted with
various combinations of hexane/methylene chloride, most of the organochlorine pesticides were
eluted from the cartridges with hexane/methylene chloride. Nonetheless, we had difficulties in
quantifying the phthalate esters in the hexane/ethyl acetate fraction. High recoveries of some
of the 16 phthalate esters were attributed to intefferents eluted from the cartridge by hexane
with 10 percent ethyl acetate and/or to contaminants in ethyl acetate that interfere with the
phthalate ester determination (Table 28).
Interferences in the determination of phthalate esters caused by the organochlorine
pesticides are presented in Table 29, and method blank analysis data for Florisil cartridges are
presented in Table 30.
The Florisil procedure was further evaluated using extracts of environmental samples
spiked with the 16 phthalate esters at known concentrations. The results presented in Table 31
indicate that recoveries were greater than 74 percent except for BEEP phthalate (recovery
ranges from 24 to 62 percent) and BMEP phthalate which could not be recovered at all in
Fraction 2.
When using these cartridges for the cleanup of extracts with the phthalate esters as
the target analytes, method blanks need to be obtained for each batch of cartridges used. The
SPE cartridges contain the adsorbent material in a polypropylene housing, and polyethylene frits
are used to hold the adsorbent material in place. Junk and co-workers (6) found C10 to C^g
isomeric alkenes, 2,6-di-te/f-butyl-p-cresoI, and alkyl phthalates in procedural blanks obtained by
washing the polypropylene housing or the polyethylene frits with ethyl acetate, methanol, and
water. We have analyzed Florisil SPE cartridges for the target analytes and found several
phthalate esters in procedural blanks (Table 32); however, their levels were not high enough to
interfere with the chromatographic determination of the organochlorine pesticides or the
phenols, and the preconditioning of cartridges should minimize sample contamination.
Furthermore, the volume of solvents needed to elute the interferents or the target analytes from
the cartridge is small (5 mL), and the residence time of the solvent in the cartridge is less than
5 min, making it quite desirable for use.
53 PHENOLS
Silica cartridges were evaluated for their use in the phenol analysis. These cartridges
were chosen because the current SW-846 Method 3630 recommends use of silica gel for cleanup
of sample extracts that were derivatized with pentafluorobenzyl bromide (PFBBr). More
specifically, a 4-g silica column is preeluted with 6 mL hexane, the derivatized extract is loaded
on the column, the column is eluted first with hexane (6 mL), then with 10 mL hexane with
15 percent toluene (Fraction 1), 10 mL hexane with 40 percent toluene (Fraction 2), 10 mL
hexane with 75 percent toluene (Fraction 3), and 10 mL toluene with 15 percent 2-propanol
(Fraction 4). Under these conditions, 9 derivatized phenols spread over the 4 fractions.
44
-------
TABLE 26. EXPERIMENTAL DESIGN FOR FLORISIL CARTRIDGE CLEANUP
METHOD DEVELOPMENT*
Amount
spiked (ng)
Sample Phthalate
identification esters
8712-013-1
8712-013-2
8712-013-3
8712-013-4
8712-013-5
8712-013-6
8712-013-7
8712-013-8
8712-013-9
8712-013-10
8712-013-11
8712-013-12
8712-013-13
8712-013-14
8712-013-15
8712-013-16
8712-013-17
8712-013-18
8712-013-22
500
500
500
500
500
500
500
500
500
500
500
500
0
0
0
500
500
500
0
OCPs
500
500
500
500
500
500
500
500
500
0
0
0
500
500
500
500
500
500
0
Fraction I
(5mL)
Hexane
Hexane
Hexane
Hexane
Hexane
Hexane
Hexane/methylene
chloride (4:1)
Hexane/methylene
chloride (4:1)
Hexane/methylene
chloride (4:1)
Hexane/methylene
chloride (4:1)
Hexane/methylene
chloride (4:1)
Hexane/methylene
chloride (4:1)
Hexane/methylene
chloride (4:1)
Hexane/methylene
chloride (4:1)
Hexane/methylene
chloride (4:1)
Hexane/methylene
chloride (4:1)
Hexane/methylene
chloride (4:1)
Hexane/methylene
chloride (4:1)
Hexane/methylene
chloride (4:1)
Fraction II
(5mL)
Hexane/diethyl ether
(1:1)
Hexane/diethyl ether
(1:1)
Hexane/diethyl ether
(1:1)
Hexane/acetone
(9:1)
Hexane/acetone
(9:1)
Hexane/acetone
(9:1)
Hexane/methylene
chloride (4:1)
Hexane/methylene
chloride (4:1)
Hexane/methylene
chloride (4:1)
Hexane/acetone
(9:1)
Hexane/acetone
(9:1)
Hexane/acetone
(9:1)
Hexane/acetone
(9:1)
Hexane/acetone
(9:1)
Hexane/acetone
(9:1)
Hexane/acetone
(9:1)
Hexane/acetone
(9:1)
Hexane/acetone
(9:1)
Hexane/acetone
(9:1)
(continued)
45
-------
TABLE 26. (continued)
Amount
spiked (ng)
Sample Phthalate
identification esters
8712-013-23
8712-013-24
8712-013-25
8712-013-26
8712-013-27
8712-013-28
8712-013-29
8712-013-30
8712-013-31
8712-013-32
8712-013-33
8712-013-34
8712-013-35
8712-013-36
8712-013-37
8712-013-38
8712-013-39
8712-013-40
8712-013-41
8712-013-42
0
500
500
500
500
500
500
500
500
500
0
0
0
500
500
500
500
500
500
500
OCPs
0
0
0
0
0
0
0
0
0
0
500
500
500
500
500
500
500
500
500
500
Fraction I
(5mL)
Hexane/methylene
chloride (85:15)
Hexane/methylene
chloride (85:15)
Hexane/methylene
chloride (85:15)
Hexane/methylene
chloride (85:15)
Hexane/methylene
chloride (75:25)
Hexane/methylene
chloride (75:25)
Hexane/methylene
chloride (75:25)
Hexane/methylene
chloride (70:30)
Hexane/methylene
chloride (70:30)
Hexane/methylene
chloride (70:30)
Hexane/methylene
chloride (85:15)
Hexane/methylene
chloride (75:25)
Hexane/methylene
chloride (70:30)
Hexane/methylene
chloride (85:15)
Hexane/methylene
chloride (85:15)
Hexane/methylene
chloride (85:15)
Hexane/methylene
chloride (75:25)
Hexane/methylene
chloride (75:25)
Hexane/methylene
chloride (75:25)
Hexane/methylene
chloride (7030)
Fraction II
(5mL)
Hexane/acetone
(9:1)
Hexane/ethyl
acetate (9:1)
Hexane/ethyl
acetate (9:1)
Hexane/ethyl
acetate (9:1)
Hexane/ethyl
acetate (9:1)
Hexane/ethyl
acetate (9:1)
Hexane/ethyl
acetate (9:1)
Hexane/ethyl
acetate (9:1)
Hexane/ethyl
acetate (9:1)
Hexane/ethyl
acetate (9:1)
Hexane/ethyl
acetate (9:1)
Hexane/ethyl
acetate (9:1)
Hexane/ethyl
acetate (9:1)
Hexane/ethyl
acetate (9:1)
Hexane/ethyl
acetate (9:1)
Hexane/ethyl
acetate (9:1)
Hexane/ethyl
acetate (9:1)
Hexane/ethyl
acetate (9:1)
Hexane/ethyl
acetate (9:1)
Hexane/ethyl
acetate (9:1)
(continued)
46
-------
TABLE 26. (concluded)
Amount
spiked (ng)
Sample Phthalate
identification esters
8712-013-43
8712-013-44
8712-013-45
8712-013-46
8712-013-47
500
500
0
0
0
OCPs
500
500
0
0
0
Fraction I
(5mL)
Hexane/methylene
chloride (70:30)
Hexane/methylene
chloride (70:30)
Hexane/methylene
chloride (85:15)
Hexane/methylene
chloride (75:15)
Hexane/methylene
chloride (70:30)
Fraction II
(5mL)
Hexane/ethyl
acetate (9:1)
Hexane/ethyl
acetate (9:1)
Hexane/ethyl
acetate (9:1)
Hexane/ethyl
acetate (9:1)
Hexane/ethyl
acetate (9:1)
(continued)
al-g Florisil cartridges were used. The 16 phthalate esters and the organochlorine
pesticides (OCPs) were spiked at 500 ng per component or not at all as indicated.
47
-------
TABLE 27. RECOVERY OF PHTHALATE ESTERS FROM 1-g FLORISIL
CARTRIDGES BY ELUTION WITH HEXANE WITH
15 PERCENT, 25 PERCENT, AND 30 PERCENT METHYLENE
CHLORIDE (FRACTION I) AND HEXANE WITH 10
PERCENT ETHYL ACETATE (FRACTION II)*
oo
Percent recovery
8712-013-24
Fraction
Compound
DMP
DEP
DIBP
DBP
BMPP
BMEP
DAP
BEEP
HEHP
DHP
BBP
BBEP
DEHP
DCP
OOP
DNP
I
15
0
0
13.1
0
0
0
0
13.7
49.0
4.0
0
0
0
0
0
II
7.0
34.5
98.0
65.0
101
0
156
6.0
91.0
40.1
73.0
0
54.0
125
94.2
803
8712-013-25
Fraction
I
5.7
0
0
13.5
0
0
0
0
0
40.2
0
0
0
0
0
0
II
6.6
37.9
60.4
80.0
102
21.0
161
6.2
90.0
42.5
81.0
0
46.0
97.5
95.3
75.4
8712-013-26
Fraction
I
4.1
0
0
0
0
0
0
0
0
43.3
0
0
0
0
0
0
II
0
40.1
64.2
85.0
105
32.8
166
5.0
101
44.3
89.0
0
56.0
110
107
82.9
8712-013-27
Fraction
I
0
0
0
0
0
0
0
0
0
46.2
27.3
0
0
0
0
0
II
13.0
65.8
64.6
112
102
23.4
143
6.8
110
50.9
95.4
0
31.3
110
108
93.4
8712-013-28
Fraction
I
12.3
0
0
0
0
0
0
0
0
46.2
24.7
0
0
0
0
0
II
0
27.3
60.7
83.7
90.7
24.2
179
0
120
44.9
84.4
0
36.2
100
99.8
81.1
8712-013-29
Fraction
I
12.6
12.9
0
0
0
0
0
0
14.7
80.5
29.2
0
0
0
0
0
II
2.2
38.6
89.8
69.8
96.6
24.2
184
17.6
89.3
51.3
93.4
0
36.0
108
108
78.8
8712-013-30
Fraction
I
4.4
0
0
0
0
0
0
0
0
0
3.7
0
0
0
0
0
II
4.3
26.6
58.6
49.8
79.4
0
159
0
115
50.7
101
0
50.0
142
104
105
8712-013-31
Fraction
I
13.6
0
0
0
0
0
0
0
0
0
6.5
0
0
0
0
0
II
13.2
27.2
53.6
52.4
78.7
18.9
108
0
120
47.2
106
0
43.9
142
100
115
8712-013-32
Fraction
I
12.8
0
0
0
0
0
0
0
0
0
1.5
0
0
0
0
0
II
12.4
24.8
56.1
51.9
79.4
18.2
103
0
101
49.2
103
0
44.9
148
106
94.3
The spiking level was 500 ng of each phthalate ester per cartridge.
-------
TABLE 28. RECOVERY OF PHTHALATE ESTERS FROM 1-g FLORISIL CARTRIDGE IN
THE PRESENCE OF ORGANOCHLORINE PESTICIDES BY ELUTION WITH
HEXANE WITH 15 PERCENT, 20 PERCENT, AND 30 PERCENT
METHYLENE CHLORIDE (FRACTION I) AND HEXANE WITH 10 PERCENT
ETHYL ACETATE (FRACTION II)"
Percent Recovery
Compound
DMP
DEP
DIBP
DBP
BMPP
BMEP
DAP
BEEP
HEHP
DHP
BBP
BBEP
DEHP
DCP
OOP
DNP
8712-013-36
Fraction
II
i6o*
49.5
150*
123
1560*
138"
5450*
ND
112
137*
123
560*
135"
112
117
43.0
8712-013-37
Fraction
II
172*
57.5
105
121
74.9
645"
5,620"
ND
102
123
124
520"
119
104
118
40.6
8712-013-38
Fraction
II
174*
60.0
108
115
72.7
224*
5,530"
ND
103
129"
117
530"
112
97.8
109
38.4
8712-013-39
Fraction
II
118
63.2
98.2
118
78.8
456"
1,420"
28.3
108
146"
127"
338"
151"
110
126"
42.0
8712-013-40
Fraction
II
112
56.3
108
121
116
162"
1,410"
26.3
113
120
125
362"
128"
110
123
43.6
8712-013-41
Fraction
II
101
56.7
99.0
108
110
185*
850*
29.2
110
113
129"
274"
119
112
126"
43.8
8712-013-42
Fraction
II
120
40.2
92.5
109
109
124
1,640"
29.0
110
126"
117
335*
220"
103
112
45.2
8712-013-43
Fraction
II
113
51.1
95.8
106
102
210"
454*
24.2
88.6
92.7
106
171"
181"
94.3
90.7
38.3
8712-013-44
Fraction
II
114
34.9
97.6
102
102
367*
881*
25.7
99.7
110
121
227*
249*
107
111
44.3
"The spiking level was 500 ng per phthalate ester per cartridge. The OCPs were also spiked at 500 ng per component per
cartridge.
* High recovery due to interferents eluted from the cartridge by hexane with 10 percent ethyl acetate and/or contaminants in ethyl acetate.
-------
TABLE 29. INTERFERENCES IN THE DETERMINATION OF PHTHALATE ESTERS
CAUSED BY ORGANOCHLORINE PESTICIDES
Concentration (nR/niL)"
8712-013-13
Fraction
Compound
DMP
DEP
DIBP
DBP
BMPP
BMEP
DAP
BEEP
HEHP
DHP
BBP
BBEP
DEHP
DCP
OOP
DNP
1
ND<
ND
23.2
64.1
1,810
6,160
370
ND
3,070
42.2
33.2
ND
48.4
ND
ND
ND
II
260
ND
24.5
34.0
660
23.8
4.220
ND
30.9
122
36.3
586
70.4
ND
ND
ND
8712-013-14
Fraction
1
ND
ND
57.3
26.2
2.250
6,420
2,070
ND
3,270
52.6
37.2
31.6
53.0
ND
ND
ND
II
227
ND
70.4
30.0
386
325
2,870
32.7
69.9
103
31.7
583
129
ND
ND
ND
8712-014-15
Fraction
1
45.2
ND
50.9
27.8
2,020
6.274
857
38.2
3.120
63.8
34.5
ND
69.3
ND
ND
ND
II
205
37.7
66.6
26.7
19.8
544
3,960
32.1
251
89.4
30.5
606
112
ND
ND
ND
8712-013-33
Fraction
1
ND
ND
45.6
28.6
1,260
7.510
557
60.4
3,540
65.1
35.8
ND
65.9
ND
ND
ND
II
208
ND
20.4
20.8
18.0
585
6,200
22.1
21.7
107
36.5
629
219
ND
ND
ND
8712-013-34 8712-013-35
Fraction Fraction
1' II 1'
137
ND
30.3
ND
130
313
1.110
21.7
19.9
87.2
33.2
346
124
ND
ND
ND
II
143
ND
36.3
ND
ND
293
491
22.1
150
63.0
28.5
99.1
76.6
ND
ND
ND
The Florisil cartridges were charged only with OCPs. The various peaks detected in these fractions as phthalate esters are probably not only
bcontaminants in the OCP standards and other materials but also OCPs eluting at the same retention times as the target analytes.
c Analysis did not pass QC criteria, results are therefore not reported..
ND - not detected; detection limit was approximately 10 ng/mL.
-------
TABLE 30. RESULTS OF METHOD BLANK ANALYSES FOR THE FLORISIL
CARTRIDGES
Concentration (ng/mL)"
8712-013-22
Fraction
Compound
DMP
I
40.7
DEP NDb
DIBP
DBP
BMPP
BMEP
DAP
BEEP
HEHP
DHP
BBP
BBEP
DEHP
DCP
DOP
DNP
ND
ND
ND
ND
63.9
ND
33.9
50.6
24.9
ND
68.8
ND
52.2
ND
II
151
ND
ND
26.8
ND
ND
137
16.3
18.6
49.8
30.2
ND
121
ND
ND
ND
8712-013-23
Fraction
I
51.9
ND
22.8
ND
ND
ND
ND
18.8
18.3
ND
35.9
ND
100
ND
64.1
ND
II
200
ND
22.1
30.1
ND
ND
139
18.2
ND
54.4
37.5
ND
114
ND
ND
ND
8712-013-45
Fraction
I
12.4
ND
ND
ND
ND
ND
ND
ND
ND
ND
35.7
ND
60.2
ND
ND
ND
II
• 55.4
ND
ND
36.8
ND
18.5
ND
14.9
16.7
40.0
35.9
ND
56.1
ND
ND
ND
8712-013-46
Fraction
I
17.0
ND
ND
36.6
ND
ND
46.8
ND
ND
ND
ND
59.1
81.1
ND
ND
ND
n
33.2
ND
ND
13.9
ND
ND
ND
14.8
ND
38.2
35.6
ND
61.1
ND
ND
ND
8712-013-47
Fraction
I
24.2
ND
ND
ND
ND
ND
61.8
ND
ND
49.0
27.1
ND
58.2
ND
ND
ND
n
32.4
ND
ND
33.1
16.4
17.9
ND
20.7
ND
35.1
24.7
56.7
58.1
ND
ND
ND
"The Florisil cartridge (1 g) was eluted with 5 mL hexane/methylene chloride (4:1) and
5 mL hexane/acetone (9:1) in the case of samples 8712-013-22, -23, and 5 mL of
85:15, 75:25, and 70:30 hexane/methylene chloride for samples -45, -46, and -47.
Fraction 2 for samples -45, -46, -47 was eluted with 5 mL hexane/ethyl acetate (9:1).
Final volume of each fraction was 5 mL.
bND -- not detected; detection limit was approximately 10 ng/mL.
51
-------
TABLE 31. PERCENT RECOVERIES OF PHTHALATE ESTERS IN EXTRACTS FROM
VARIOUS MATRICES SUBJECTED TO FLORISIL CARTRIDGE CLEANUP
WITH HEXANE/METHYLENE CHLORIDE (4:1) AND HEXANE/
ACETONE (9:1) AS ELUANTS*
Compound
BMP
DEP
DIBP
DBF
BMPP
BMEP
DAP
BEEP
HEHP
DHP
BBP
BBEP
DEHP
DCP
DOP
DNP
Sandy loam
soilb
78
79
79
74
77
0
82
37
80
78
82
86
74
91
80
84
Sediment
of undefined
origin
75
79
82
78
84
0
86
24
88
88
99
94
85
96
92
96
NBS
SRM-1572
80
89
90
84
102
0
100
62
95
86
114
98
108
106
104
106
NBS
SRM-1632a
76
79
108
83
91
0
76
32
93
92
102
106
88
98
95
111
NBS
SRM-1633a
82
84
86
83
86
0
89
33
81
80
98
98
112
95
88
92
a The spiking level was 50 ng/mL of extract for each compound. Data shown are for
Fraction 2 which was eluted with 5 mL hexane/acetone (9:1).
b Sandy loam soil from Puyallup, Washington, with the following characteristics: pH 5.9
to 6.0; 89 percent sand, 7 percent silt, 4 percent clay; cation exchange capacity 7
meg/100 g; total organic carbon content 1,290 ± 185 nig/Kg.
52
-------
TABLE 32. METHOD DETECTION LIMIT STUDY—FLORISIL
CARTRIDGES METHOD BLANKS
Concentration (ng/cartridge)*
Compound Rep.l Rep.2 Rep-3 Rep.4 Rep.5 Average
SD
DMP
DEP
DIBP
DBP
BMPP
BMEP
DAP
BEEP
HEHP
DHP
BBP
BBEP
DEHP
DCP
DOP
DNP
412
192
94.7
129
60.0
303
28.4
69.2
43.9
32.9
16.6
30.4
295
<10
<10
<10
411
76.2
96.6
116
73.3
134
40.3
61.9
16.2
29.3
16.1
29.8
267
<10
<10
<10
466
155
107
142
106
302
140
65.3
40.3
31.6
16.6
42.2
332
<10
<10
<10
*
495
228
119
162
152
291
33.6
64.2
12.9
35.8
24.3
59.0
320
18.2
13.8
<10
496
144
107
132
51.9
282
22.0
71.2
4.7
33.2
18.2
43.1
243
<10
<10
<10
456
159
105
136
88.6
262
52.9
66.4
23.6
32.6
18.4
40.9
291
<10
<10
<10
42
66
10
17
41
72
49
4
17
2
3
12
37
—
—
—
Each Florisil cartridge (Supelco, Inc.) was eluted with 5 mL hexane
with 20 percent methylene chloride (Fraction 1) which was discarded,
followed by 5 mL of hexane/acetone (9:1) which was concentrated to
1 mL and analyzed by GC/ECD. The GC/ECD operating conditions
were as follows: 30 m x 0.25 mm ID DB-5 fused-sUica capillary column
(0.25 urn film thickness); 120°C to 260°C (hold 15.7 min) at 15°C/min;
carrier gas helium at 21 psi; injector temperature 275°C; detector
temperature 320°C; splitless injection.
53
-------
We have taken 1-g silica cartridges, charged them with the PFB derivatives of
20 phenols, and eluted the cartridges with 4 mL hexane followed by 5 mL hexane with
25 percent toluene. Under these conditions, we got quantitative recoveries of 18 of the
20 compounds. When 0.5-g silica cartridges were evaluated at three spike levels (Table 33), we
found that the 18 phenols elute primarily in Fraction 1.
As the cartridge size increases, we see a crossover into Fraction 2 (Table 34), and when
the 2-g cartridges were used, 18 compounds were recovered quantitatively in Fraction 2
(Table 35).
Matrix interferents such as corn oil, diesel hydrocarbons, and elemental sulfur were
added to hexane solutions of the target phenols at known concentrations, and the solutions were
then subjected to the silica cartridge cleanup procedure to establish if any changes occurred in
the compound elution pattern and in their recovery when matrix interferents were present
(Table 36). No change in compound recovery or elution pattern was observed.
The silica cartridge procedure for the phenols was tested with three extracts of
environmental samples spiked with the target compounds at known concentrations. After
spiking, the extracts were derivatized with PFBBr using the Lee, et al., procedure (2) and
cleaned by the silica cartridge cleanup procedure. The recovery data are presented in Table 37.
5.4 EVALUATION OF THE ASPEC SYSTEM
The Gilson ASPEC system (Automatic Sample Preparation with Extraction Columns)
was loaned to us for a period of three weeks by Gilson Medical Electronics, Inc. The ASPEC
system is designed to receive either 100-mg cartridges or 500-mg cartridges. The ASPEC
software comprises several prestored programs and 8 KB of user memory for free programming.
In the standard program, the user enters the parameters via a limited number of easy prompts
that indicate the conditioning step, washing step, elution step, and collected fraction mixing step.
We have used the standard program available with the instrument (File 165) and
modified it to allow the evaluation of the silica and diol cartridges for the cleanup of samples
containing organochlorine pesticides and Aroclor 1260 (Tables 38,39, and 40) or organochlorine
pesticides and corn oil, diesel hydrocarbons, Aroclor 1260, and elemental sulfur (Table 41).
Furthermore, sample extracts (identified as SS-2, SS-5, SS-7 and SS-8) were processed using
the ASPEC system and 0.5-g diol cartridges (Tables 42 through 45).
Overall, the method reproducibility using the ASPEC system with the 0.5-g diol
cartridges is excellent. Thirteen out of 17 organochlorine pesticides had RSDs under 4 percent
(Table 40), and there was no crosscontamination when interferents were added such as corn oil,
diesel hydrocarbons, and when sample extracts were used.
Slight modifications to the cartridge procedure had to be made when using the ASPEC
system. For example, the ASPEC system does not allow collection of more than one fraction
per extract. Since the silica cartridge procedure for the organochlorine pesticides calls for
elution of the cartridge with 5 mL hexane followed by 5 mL hexane with 50 percent diethyl
ether we first eluted the cartridges with 5 mL hexane which was discarded and followed with
3.5 mL hexane with 50 percent diethyl ether (Table 38). Under those conditions, heptachlor,
aldrin, 4,4'-DDE, and 4,4'-DDT were not recovered since they are eluted from the cartridge
with hexane. To collect Fraction 1, we had to elute all cartridges on the ASPEC rack with
54
-------
TABLE 33. ELUTION PATTERNS AND PERCENT RECOVERIES OF THE PFB
DERIVATIVES OF PHENOLS FROM 0.5-g SILICA CARTRIDGES'
Spiked at 0.4 fig
per cartridge
Compound Fraction 1
Phenol
2-Methylphenol
3-Methylphenol
4-Methylphenol
2,4-DimethylphenoI
2-Chlorophenol
2,6-Dichlorophenol
4-Chloro-3-methylphenol
2,4-Dichlorophenol
2,4,6-Trichlorophenol
2,3,6-Trichlorophenol
2-Nitrophenol
2,4,5-Tricruorophenol
2,3,5-Trichlorophenol
2,3,5,6-Tetrachloropheno!
2,3,4,6-Tetrachlorophenol
23,4-TrichJorophenol
2,3.44-Tetrachlorophenol
Pentachlorophenol
2,4-Dinitrophenol
87.3
103
100
94.9
100
87.1
113
115
88.9
119
117
ND"
69.8
69.8
103
85.0
89.5
III
117
ND
90.0
103
100
85.1
100
73.6
113
112
76.6
121
118
ND
80.5
80.5
100
76.3
913
104
119
ND
Fraction 2
0
0
0
5.1
0
12.9
0
0
11.1
0
0
ND
30.2
30.2
0
15.0
19.4
0
0
ND
0
0
0
14.9
0
26.4
0
0
23.4
0
0
ND
29.5
29.5
0
23.7
31.5
0
0
ND
Spiked at OJt fig
per cartridge
Fraction 1
79.0
96.8
96.8
88.8
108
87.3
112
113
93.3
116
113
ND
122
122
107
106
54.0
91.3
104
ND
82.8
99.3
100
93.3
111
94.3
114
114
101
120
115
ND
126
126
110
108
68.5
94.3
105
ND
Fraction 2
9.8
0
7.5
16.3
0
24.8
0
0
22.8
0
0
ND
0
0
0
0
51.3
12.0
0
ND
10.8
0
15.8
0
0
18.3
0
0
17.7
0
0
ND
0
0
0
0
39.6
10.5
0
ND
Spiked at 0.05 0g
per cartridge
Fraction 1
69.0
88.3
86.0
76.5
90.8
76.5
92.3
93.8
81.5
97.3
98.0
ND
90.8
90.8
104
102
64.0
98.0
117
ND
70.5
88.3
86.8
77.5
91.0
77.0
92.8
94.3
82.8
96.8
97.8
ND
90.5
90.5
104
100
55.8
95.8
114
ND
Fraction 2
5.0
0
4.5
10.5
0
13.5
0
0
12.8
0
0
64.0
0
0
0
0
40.7
10.3
0
ND
4.8
0
4.5
9.8
0
13.5
0
0
13.0
0
0
42.3
0
0
0
0
48.5
10.3
0
ND
' 0.5-g silica cartridges (Supelco lot SP016I) were used in this experiment. Each cartridge was conditioned with 4 mL hexane prior to use. Fraction 1
was eluted with 5 mL hexane. Fraction 2 was eluted with 5 mL hexane with 25 percent toluene. The two values given for each fraction represent data
from duplicate experiments.
8 ND--not detected.
-------
TABLE 34. ELUTION PATTERNS AND PERCENT RECOVERIES OF THE PFB
DERIVATIVES OF PHENOLS FROM 1-g SILICA CARTRIDGES'
Spiked at 0.4 0g
per cartridge
Compound
Phenol
2-Methylphenol
3-Methylphenol
4-MethyIphenol
2,4-Dimethylpheno!
2-Chlorophenol
2,6-Dichlorophenol
4-Chloro-3-methylphenol
2,4-Dichlorophenol
2,4.6-Trichlorophenol
2,3.6-Trichlorophenol
2-Nitrophenol
2A5-Trichlorophenol
23,5-Trichlorophenol
2,3,5,6-Tetrachloropnenol
23,4,6-Tetrachlorophenol
2,3,4-Trichlorophenol
2,3,4,5-TetrachJorophenol
Pentachlorophenol
2,4-Dinitrophenol
Fraction 1
0
8.8
0
0
0
0
59.8
0
0
119
96.8
ND"
3.3
3.3
122
122
88.6
0
118
ND
0
34.6
0
0
17.6
0
89.0
0
0
120
109
ND
15.3
15.3
121
121
42.5
0
116
ND
Fraction 2
95.6
101
112
113
115
119
69.8
119
122
7.4
31.3
ND
109
109
5.6
5.6
5.1
118
6.1
ND
96.5
790
III
114
104
117
37.1
110
123
4.9
14.5
ND
106
106
4.1
4.1
57.5
119
6.3
ND
Spiked at 0.2 /Jg
per cartridge
Fraction 1
9.8
0
0
0
0
0
41.6
0
0
96.6
73.3
ND
0
0
89.7
87.7
0
0
86.3
ND
10. 1
0
0
0
{)
0
36.7
0
0
94.5
67.5
ND
0
0
88.4
88.4
0
0
85.6
ND
Fraction 2
74.0
78.1
87.7
K9.0
94.5
91.1
55.5
94.5
96.6
0
22.9
ND
too
100
0
0
87.7
89.0
0
ND
62.3
62.2
72.6
72.6
74.7
76.0
47.3
78.1
80.8
0
25.5
ND
87.0
87.0
0
0
78.1
82.9
0
ND
Spiked at 0.05 /Jg
per cartridge
Fraction 1
26.5
81.8
28.3
15.3
71.0
0
97.3
64.0
5.0
103
103
ND
51.8
51.8
no
112
0
16.8
126
ND
23.5
KI.5
23.K
n.n
71.0
0
95.8
63.0
0
102
101
ND
49.8
49.8
108
110
0
12.8
122
ND
Fraction 2
49.5
14.5
66.0
78.3
29.0
93.8
5.3
37.0
98.5
0
5.3
ND
43.3
43.3
0
0
112
93.3
5.8
ND
52.0
13.2
70.0
81.0
28.8
94.5
4.5
36.8
100
0
5.3
ND
44.5
44.5
0
0
109
98.8
5.3
ND
* 1-g silica cartridges (Supelco lot SP016I) were used in this experiment. Each cartridge was conditioned with 4 mL hexane prior to use. Fraction 1
was eluted with 5 mL hexane. Fraction 2 was eluted with 5 mL hexane with 25 percent toluene. The two values given for each fraction represent data
from duplicate experiments.
* ND - not detected.
-------
Ul
-J
TABLE 35. ELUTION PATTERNS AND PERCENT RECOVERIES OF THE PFB
DERIVATIVES OF PHENOLS FROM 2-g SILICA CARTRIDGES"
Spiked al 0.4 jig
per cartridge
Cowpoond Fraction 1
Phenol
2-Methylphenol
3-MethylphenoI
4-Methylphenol
2,4-Dimethylphenol
2-Chlorophenol
2.6-Dichlorophenol
4-Chloro-3-methylphenol
2,4-Dichlorophenol
2,4,6-TrichIorophenol
2,3,6-TrichlorophenoI
2-Nitrophenol
2,4,5-Trichtorophenol
2,3,5-Trichlorophenol
23,5.6-TetracWorophenol
2,3,4,6-Tetrachlorophenol
2^,4-Trichlorophenol
23,4,5-Tetracnlorophenol
Pentachlorophenol
2,4-Dinitrophenol
0
0
0
0
0
0
0
0
0
0
0
ND"
0
0
0
0
0
0
0
ND
0
0
0
0
0
0
0
0
0
0
0
ND
0
0
0
0
0
0
0
ND
Fraction 2
70.8
77.8
79.2
79.2
84.7
82.6
85.4
87.5
88.9
90.3
88.2
ND
80.6
80.6
100
100
67.6
87.5
85.4
ND
79.4
87.2
87.2
87.2
95.2
92.8
83.3
99.2
100
too
98.4
ND
92.0
92.0
96.0
96.0
74.3
98.4
89.6
ND
Spiked at 0-2 /tg
per cartridge
Fraction 1
14.5
0
0
0
0
0
0
0
0
0
0
ND
0
0
0
0
0
0
0
ND
15.0
0
0
0
0
0
0
0
0
0
0
ND
0
0
0
0
0
0
0
ND
Fraction 2
72.8
80.4
84.2
80.4
89.9
85.4
91.1
91.1
93.7
98.8
93.0
ND
97.5
97.5
90.5
89.9
77.8
85.4
87.3
ND
72.8
80.4
82.9
81.0
91.1
88.6
91.8
93.7
95.6
100
94.9
ND
99.4
99.4
90.5
91.8
85.4
88.4
91.1
ND
Spiked al 0.05 0g
per cartridge
Fraction 1
0
0
0
0
0
0
0
0
0
0
0
ND
0
0
0
0
0
0
0
ND
0
0
0
0
0
0
0
0
0
0
0
ND
0
0
0
0
0
0
0
ND
Fraction 2
76.2
94.3
94.8
87.3
98.3
90.3
100
103
too
105
106
ND
99.3
99.3
110
109
70.0
111
122
ND
72.3
88.8
90.3
81.0
91.5
91.5
90.5
91.8
88.5
92.5
93.0
ND
84.8
84.8
98.0
95.3
58.5
100
102
ND
*2-g silica cartridges (Supelco lot SPOI61) were used in this experiment. Each cartridge was conditioned with 4 mL hexane prior to use. Fraction 1
was eluted with 5 mL hexane. Fraction 2 was eluted with 5 mL hexane with 25 percent toluene. The two values given for each fraction represent data
from duplicate experiments.
* ND - not detected.
-------
TABLE 36. PERCENT RECOVERIES AND ELUTION PATTERNS OF PHENOLS FROM 1-g SILICA
CARTRIDGES IN THE PRESENCE OF CORN OIL AND DIESEL HYDROCARBONS
Corn oil as
Compound
Phenol
2-Methylphenol
3-Methylphenol
4-Methylphenol
2,4-Dimethylphenol
2-Chlorophenol
2,6-Dichlorophenol
4-Chloro-3-methylphenol
2,4-Dichlorophenol
2,4,6-Trichlorophenol
2,3,6-Trichlorophenol
2-Nitrophenol
2,4,5-Trichlorophenol
2,3,5-Trichlorophenol
2,3,5,6-Tetrachlorophenol
2,3,4,6-Tetrachlorophenol
2,3,4-Trichlorophenol
2,3,4,5-Tetrachlorophenol
Pentachlorophenol
2,4-Dinitrophenol
Fraction 1
0
5.0
0
0
0
0
35.8
0
0
87.0
61.6
NDb
0
0
88.4
93.6
0
0
74.9
ND
0
0
0
0
0
0
18.9
0
0
81.6
45.5
ND
0
0
83.1
83.4
0
0
70.7
ND
interferent
Diesel hydrocarbons as inteiferents
Fraction 2
68.8
85.9
82.8
71.0
84.2
80.6
63.1
78.9
80.7
0
33.2
ND
126
126
0
4.7
76.5
82.0
0
ND
69.4
87.9
83.8
68.6
84.8
80.9
72.8
78.4
80.3
8.1
48.7
ND
125
125
5.0
9.9
76.6
81.8
0
ND
Fraction 1
0
0
0
0
0
0
9.9
0
0
76.4
34.9
ND
0
0
78.4
80.0
0
0
66.5
ND
0
7.0
0
0
0
0
30.6
0
0
86.0
57.1
ND
0
0
89.7
93.3
0
0
76.4
ND
Fraction 2
57.6
77.9
75.1
62.0
74.6
71.6
69.0
70.8
71.4
6.5
46.2
ND
118
118
0
7.9
74.5
74.4
5.3
ND
61.2
80.6
79.6
68.2
80.1
77.0
64.2
75.6
77.6
6.6
37.2
ND
123
123
5.1
8.1
78.0
81.6
4.8
ND
' 1-g silica cartridges (J. T. Baker lot B51505) were used in this experiment. Each cartridge was conditioned
with 4 mL hexane prior to use. Fraction 1 was eluted with 5 mL hexane. Fraction 2 was eluted with 5 mL
hexane with 25 percent toluene. Spiking level was 0.4 /ig of derivatized phenols per cartridge.
bND - not detected.
-------
VO
TABLE 37. PERCENT RECOVERIES AND ELUTION PATTERNS OF PHENOLS FROM 1-g SILICA CARTRIDGES
IN THE PRESENCE OF MATRIX INTERFERENTS
Sample 1
Compound
Phenol
2-Methylphenol
3-Methylphenol
4-Methylphenol
2,4-Dimethylphenol
2-Chlorophenol
2,6-Dichlorophenol
4-Chloro-3-methylphenol
2,4-Dichlorophenol
2,4,6-Trichlorophenol
2,3,6-Trichloropnenol
2-Nitrophenol
2,4,5-Trichlorophenol
2,3,5-Trichloropnenol
2,3,5,6-Tetrachlorophenol
2,3,4,6-Tetrachlorophenol
2,3,4-Trichlorophenol
2,3,4,5-Tetrachlorophenol
Pentachlorophenol
2,4-Dinitrophenol
Fraction 1
0
4.5
0
0
0
0
32.4
0
0
78.6
56.1
NDb
0
0
79.8
83.6
0
0
68.4
ND
0
2.6
0
0
0
0
23.5
0
0
77.3
47.1
ND
0
0
79.1
80.5
0
0
68.4
ND
Fraction 2
67.6
75.1
74.3
47.1
64.4
77.5
61.3
74.9
78.3
5.6
32.4
ND
68.8
68.8
3.9
5.2
74.3
80.1
3.7
ND
68.3
76.9
74.4
44.3
64.9
77.6
67.9
75.5
78.4
10.2
44.0
ND
68.5
68.5
7.4
10.4
77.8
81.4
6.2
ND
Sample 2
Fraction 1
0
0
0
0
0
0
18.8
0
0
77.1
43.0
ND
0
0
77.0
76.6
0
0
60.9
ND
0
0
0
0
0
0
10.9
0
0
70.8
32.3
ND
0
0
69.9
68.6
0
0
56.2
ND
Fraction 2
72.8
54.4
85.1
85.1
35.1
80.1
74.0
78.6
80.6
13.4
51.6
ND
133
133
9.5
I
J 101
80.6
6.8
ND
66.3
49.0
48.6
30.1
30.6
74.6
72.5
72.3
74.6
10.3
50.8
ND
124
124
6.9
10.6
71.3
72.9
5.1
ND
Sample 3
Fraction 1
0
0
0
0
0
0
20.0
0
0
76.3
43.3
ND
0
0
79.0
87.4
9.6
0
77.6
ND
0
0
0
0
0
0
18.9
0
0
74.7
42.0
ND
0
0
76.9
86.9
9.6
0
76.9
ND
Fraction 2
64.8
68.0
68.6
43.1
51.2
79.2
71.5
77.4
79.7
11.6
48.8
ND
123
123
7.5
12.1
78.5
85.1
7.5
ND
63.4
66.3
66.9
42.0
49.3
78.2
70.1
76.3
77.9
11.0
47.8
ND
122
122
6.9
11.6
76.1
82.0
3.7
ND
* 1-g silica cartridges (J.T. Baker lot 51505) were used in this experiment Each cartridge was conditioned with 4 mL hexane prior to
use. Fraction 1 was eluted with 5 mL hexane. Fraction 2 was eluted with 5 mL hexane with 25 percent toluene. Spiking level was
0.4 fig of derivatized phenols per cartridge.
bND--Not delected.
a
w
-------
TABLE 38. METHOD REPRODUCIBILITY USING THE ASPEC ROBOTIC SYSTEM*
OCPs only
OCPs and Aroclor 1260
Compound
alpha-BHC
gamma-BHC
beta-BHC
Heptachlor
delta-BHC
Aldrin
Heptachlor epoxide
Endosulfan I
4,4 '-DDE
Dieldrin
Endrin
4,4 '-DDD
Endosulfan II
4,4 '-DDT
Endrin aldehyde
Endosulfan sulfate
4,4 '-Methoxychlor
Average
recovery
46.8
89.8
88.5
0
88.0
0
91.6
88.8
0
86.7
106
25.4
74.9
0
35.3
78.5
89.2
Percent
RSD
6.2
2.9
3.6
~
3.2
—
7.6
3.8
~
3.4
4.5
8.6
3.4
--
5.4
4.3
8.2
Average
recovery
89.1
91.1
90.4
0
89.5
0
89.1
88.8
0
88.6
110
72.7
76.6
17.2
32.7
77.4
86.8
Percent
RSD
1.6
4.4
4.7
—
5.4
«
5.0
5.3
—
5.4
5.8
5.5
5.3
96
7.5
5.6
6.3
a0.5-g silica cartridges (J. T. Baker) were used for this experiment. Each cartridge was
conditioned with 4 mL hexane (speed 5; air volume 100 /*L). Standard in hexane
(1 mL) was added to the cartridge (height 0, speed 4, air volume 100 /iL). The
cartridge was washed with 5 mL hexane (speed 5, air volume 100 /iL) and eluted with
3.5 mL hexane with 50 percent diethyl ether (speed 4, air volume 200 pL). Finally, to
clean the lines, the cartridge was rinsed with 1 mL hexane with 50 percent diethyl
ether (speed 8) and the rinse was discarded. Spiking level was 1 fig per cartridge for
the OCPs and 10 /ig per cartridge for Aroclor 1260. Number of determinations was 4.
60
-------
TABLE 39. METHOD REPRODUCIBILITY USING THE ASPEC ROBOTIC SYSTEM8
Average recovery (percent RSD)
OCPs only
OCPs and Aroclor 1260
Compound
alpha-BHC
gamma-BHC
beta-BHC
Heptachlor
delta-BHC
Aldrin
Heptachlor epoxide
Endosulfan I
4,4 '-DDE
Dieldrin
Endrin
4,4 '-ODD
Endosulfan II
4,4 '-DDT
Endrin aldehyde
Endosulfan sulfate
4,4 '-Methoxychlor
Fraction
1
0
0
0
83.7 (3.6)
0
82.6 (4.8)
0
0
86.2 (5.7)
0
0
0
0
67.8 (12.3)
0
0
0
Fraction
2
84.7 (2.6)
87.1 (2.5)
84.4 (1.4)
0
81.5 (2.5)
0
82.2 (3.0)
82.0 (3.3)
0
78.8 (3.2)
88.7 (3.0)
82.4 (2.8)
80.5 (2.8)
15.4 (93)
21.2 (8.8)
73.2 (4.6)
78.5 (3.2)
Fraction
1
0
0
0
71.4 (7.8)
0
79.9 (1.4)
0
0
80.5(3.3)
b
b
0
b
82.9 (2.2)
b
b
b
Fraction
2
84.0 (1.7)
85.6 (1.3)
82.2 (1.1)
21.4 (49)
79.4 (2.6)
0
83.0 (2.5)
84.1 (2.5)
8.5 (85)
80.8 (2.6)
91.5 (3.2)
81.6 (1.3)
79.6(1.7)
b
17.7 (2.9)
43.4 (2.2)
80.4 (2.0)
a0.5-g silica cartridges (J. T. Baker) were used for this experiment. Each
cartridge was conditioned with 4 mL hexane (speed 5; air volume 100 0L).
Standard in hexane (1 mL) was added to the cartridge (height 0, speed 4, air
volume 100 /iL). The cartridge was eluted with 3.5 mL hexane (Fraction 1,
speed 4, air volume 200 /iL) followed by 3.5 mL hexane with 50 percent diethyl
ether (Fraction 2, speed 4, air volume 200 /tL). Finally, to clean the lines, the
cartridge was rinsed with 1 mL hexane with 50 percent diethyl ether (speed 8)
and the rinse was discarded. Spiking level was 1 /Jg per cartridge for the OCPs
and 10 /ig per cartridge for Aroclor 1260. Number of determinations was 4.
blnterference from Aroclor 1260.
61
-------
TABLE 40. METHOD REPRODUCIBILITY USING
THE ASPEC ROBOTIC SYSTEM*
Compound
alpha-BHC
gamma-BHC
beta-BHC
Heptachlor
delta-BHC
Aldrin
Heptachlor epoxide
Endosulfan I
4,4 '-DDE
Dieldrin
Endrin
4,4 '-ODD
Endosulfan II
4,4 '-DDT
Endrin aldehyde
Endosulfan sulfate
4,4'-Methoxychlor
Average
recovery
86.1
87.1
81.9
86.1
83.8
86.2
86.0
85.3
85.4
86.3
108
84.0
84.6
84.7
52.9
58.1
79.4
Percent
RSD
3.0
2.9
3.3
3.2
3.2
3.2
3.3
3.6
3.4
3.3
4.5
3.7
3.3
3.6
4.9
10
4.6
a0.5-g diol cartridges (Supelco, Inc.) were used for
this experiment. Each cartridge was conditioned
with 4 mL hexane with 10 percent acetone (speed 5,
air volume 100 /iL). Standard in hexane (1 mL) was
added to the cartridge (height 0, speed 4, air volume
100 /iL). The cartridge was eluted with 3.5 mL
hexane with 10 percent acetone (speed 4, air
volume 200 ML). Finally, to dean the lines, the
cartridge was rinsed with 1 mL hexane with
10 percent acetone (speed 8) and the rinse was
discarded. Spiking level was 1 jig per cartridge. All
fractions were adjusted to 5 mL final volume.
Number of determinations was 19.
62
-------
TABLE 41. EVALUATION OF MATRIX INTERFERENTS USING THE ASPEC
ROBOTIC SYSTEM'
Percent recovery
Compound
alpha-BHC
gamma-BHC
beta-BHC
Heptachlor
delta-BHC
Aldrin
Heptachlor epoxide
Endosulfan I
4,4 'DDE
Dieldrin
Endrin
4,4 '-DDD
Endosulfan II
4,4 '-DDT
Endrin aldehyde
Endosulfan sulfate
4,4 '-Methoxychlor
Corn oil Diesel hydrocarbons1*
93.2
95.0
80.2
95.6
87.4
92.8
91.6
89.6
89.0
89.6
117
85.6
82.0
82.6
42.6
47.4
78.4
98.8
100
85.4
101
92.2
98.6
97.0
94.8
94.4
94.6
126
91.2
86.8
88.0
42.8
39.0
84.2
90.0
93.8
78.4
94.4
87.0
92.2
92.8
91.8
93.4
91.0
132
89.8
85.2
86.2
43.0
44.0
80.0
Aroclor 1260
and sulfur
108
112
85.5
110
97.4
104
96.7
93.7
106
107
89.4
93.4
97.7
127
54.1
43.7
101
110
113
87.5
113
99.0
107
98.3
95.7
111
110
91.0
94.7
99.7
130
54.1
41.3
102
a 0.5-g diol cartridges (Supelco Inc.) were used for this experiment. Each cartridge was
conditioned with 4 mL hexane with 10 percent acetone (speed 5, air volume 100 /iL).
Standards in hexane (1 mL) containing OCPs at 1 /ig/mL and corn oil at 500 /Jg/mL or diesel
hydrocarbons at 500 Jig/mL or Aroclor 1260 at 0.66 Mg/mL or elemental sulfur at 166 lig/rnL
were added to the cartridge (height 0, speed 4, air volume 100 fiL). The cartridge was eluted
with 3.5 mL hexane with 10 percent acetone (speed 4, air volume 200 /iL). Finally, to clean
the lines, the cartridge was rinsed with 1 mL hexane with 10 percent acetone (speed 8) and the
rinse was discarded.
b Duplicate experiments were also performed in this case but one fraction was lost.
63
-------
TABLE 42. PERCENT RECOVERIES OF 17 ORGANOCHLORINE
PESTICIDES SPIKED INTO SS-2 SOIL EXTRACT*
Compound
alpha-BHC
gamma-BHC
beta-BHC
Heptachlor
delta-BHC
Aldrin
HeptachJor epoxide
Endosulfan I
4,4 '-DDE
Dieldrin
Endrin
4,4 '-DDD
Endosulfan II
4,4 '-DDT
Endrin aldehyde
Endosulfan sulfate
4,4 '-Methoxychlor
Diazinon
Ethion
Ziram
Carbaryl
Unspiked
sample
(WJ/kg)
<170
<170
<170
<170
<170
<170
<170
<170
1,100
<170
<170
2,800
<170
2,200
<170
<170
<170
320
210
4,100
20
Percent
Fraction 1
82.1
81.2
76.7
73.8
40.2
88.7
79.4
68.1
b
76.7
92.2
b
80.4
b
25.2
64.5
80.0
c
c
c
c
recovery
Fraction 2
0
0
0
0
52.8
0
0
0
0
0
0
0
0
0
38.9
0
0
c
c
c
c
a Spiking level is equivalent to 330 /Jg/kg of sample. 0.5-g diol
cartridges (Burdick and Jackson) were used for this experiment.
Each cartridge was conditioned with 4 mL hexane (speed 5, air
volume 100 fiL). Sample extract (1 mL) was added to the
cartridge (height 0, speed 4, air volume 100 fiL). The cartridge
was eluted with 3 mL hexane for Fraction 1 and 3.5 mL hexane
with 10 percent acetone for Fraction 2 (speed 4, air volume
200 fiL). Finally, to dean the lines, the cartridge was rinsed with
1 mL hexane with 10 percent acetone (speed 8) and the rinse
was discarded. Single determination.
bNot able to determine recovery because the amount spiked is
lower than the background level.
°Not spiked.
64
-------
TABLE 43. PERCENT RECOVERIES OF 17 ORGANOCHLORINE
PESTICIDES SPIKED INTO SS-5 SOIL EXTRACT"
Compound
alpha-BHC
gamma-BHC
beta-BHC
Heptachlor
delta-BHC
Aldrin
Heptachlor epoxide
Endosulfan I
4,4 '-DDE
Dieldrin
Endrin
4,4 '-ODD
Endosulfan II
4,4 '-DDT
Endrin aldehyde
Endosulfan sulfate
4,4 '-Methoxychlor
Benomyl
Carbophenothion
Ethion
Unspiked
sample
(Mg/kg)
<170
<170
<170
<170
<170
<170
<170
<170
780
<170
<170
2,200
210
1,300
<170
260
<170
200
1,400
650
Percent
Fraction 1
85.4
83.6
80.1
77.6
42.8
70.4
84.0
69.2
b
76.6
90.3
b
65.3
b
25.4
50.8
72.5
c
c
c
recovery
Fraction 2
0
0
0
0
53.8
0
0
0
0
0
0
0
0
0
42.4
14.8
0
c
c
c
a Spiking level is equivalent to 330 MgAg of sample. 0.5-g diol
cartridges (Burdick and Jackson) were used for this experiment.
Each cartridge was conditioned with 4 mL hexane (speed 5, air
volume 100 ML). Sample extract (1 mL) was added to the
cartridge (height 0, speed 4, air volume 100 0L). The cartridge
was eluted with 3 mL hexane for Fraction 1 and 3.5 mL hexane
with 10 percent acetone for Fraction 2 (speed 4, air volume
200 0L). Finally, to clean the lines, the cartridge was rinsed with
1 mL hexane with 10 percent acetone (speed 8) and the rinse
was discarded. Single determination.
bNot able to determine recovery because the amount spiked is
lower than the background level.
°Not spiked.
65
-------
TABLE 44. PERCENT RECOVERIES OF 17 ORGANOCHLORINE
PESTICIDES SPIKED INTO SS-7 SOIL EXTRACT"
Compound
alpha-BHC
gamma-BHC
beta-BHC
Heptachlor
delta-BHC
Aldrin
Heptachlor epoxide
Endosulfan I
4,4 '-DDE
Dieldrin
Endrin
4,4 '-DDD
Endosulfan II
4,4 '-DDT
Endrin aldehyde
Endosulfan sulfate
4,4 '-Methoxychlor
Carbaryl
Diazinon
Ethion
Ziram
Unspiked
sample
(wz/kg)
<170
<170
<170
<170
<170
<170
<170
<170
720
<170
<170
470
300
680
<170
<170
<170
130
260
130
2,100
Percent
Fraction 1
80.1
76.4
72.4
72.4
40.1
65.7
94.4
63.8
b
98.2
110
b
38.3
b
52.1
73.5
89.3
c
c
c
c
recovery
Fraction 2
0
0
0
0
46.7
0
0
0
0
0
0
0
0
0
38.8
18.3
12.3
c
c
c
c
3 Spiking level is equivalent to 330 Jig/kg of sample. 0.5-g diol
cartridges (Burdick and Jackson) were used for this experiment.
Each cartridge was conditioned with 4 mL hexane (speed 5, air
volume 100 /*L). Sample extract (1 mL) was added to the
cartridge (height 0, speed 4, air volume 100 /iL). The cartridge
was eluted with 3 mL hexane for Fraction 1 and 3.5 mL hexane
with 10 percent acetone for Fraction 2 (speed 4, air volume
200 /iL). Finally, to clean the lines, the cartridge was rinsed with
1 mL hexane with 10 percent acetone (speed 8) and the rinse
was discarded. Single determination.
bNot able to determine recovery because the amount spiked is
lower than the background level.
cNot spiked.
66
-------
TABLE 45. PERCENT RECOVERIES OF 17 ORGANOCHLORINE
PESTICIDES SPIKED INTO SS-8 SOIL EXTRACT
Compound
alpha-BHC
gamma-BHC
beta-BHC
Heptachlor
delta-BHC
Aldrin
Heptachlor epoxide
Endosulfan I
4,4 '-DDE
Dieldrin
Endrin
4,4 '-ODD
Endosulfan II
4,4 '-DDT
Endrin aldehyde
Endosulfan sulfate
4,4 '-Methoxychlor
Benomyl
Carbaryl
Carbophenothion
Diazinon
Malathion
Ziram
Unspiked
sample
0*g/kg)
<170
<170
<170
<170
<170
<170
<170
<170
860
<170
<170
<170
<170
1,130
<170
<170
<170
200
480
3,800
135,000
230
1,200
Percent
Fraction 1
83.4
81.3
75.8
73.5
42.0
68.1
101
110
b
107
95.7
76.0
77.2
b
51.8
45.8
60.6
c
c
c
c
c
c
recovery
Fraction 2
0
0
0
0
48.9
0
0
0
0
0
0
0
0
0
0
40.9
17.3
c
c
c
c
c
c
* Spiking level is equivalent to 330 Mg/kg of sample. 0.5-g diol
cartridges (Burdick and Jackson) were used for this experiment.
Each cartridge was conditioned with 4 mL hexane (speed 5, air
volume 100 jiL). Sample extract (1 mL) was added to the
cartridge (height 0, speed 4, air volume 100 /iL). The cartridge
was eluted with 3 mL hexane for Fraction 1 and 3.5 mL hexane
with 10 percent acetone for Fraction 2 (speed 4, air volume
200 /iL). Finally, to clean the lines, the cartridge was rinsed with
1 mL hexane with 10 percent acetone (speed 8) and the rinse
was discarded. Single determination.
bNot able to determine recovery because the amount spiked is
lower than the background level.
c Not spiked.
67
-------
hexane, then proceeded to the next solvent which was hexane with 50 percent diethyl ether.
Another modification made to the cartridge procedure affected the volume of solvent needed
to elute the compounds from the cartridge. The ASPEC system cannot handle fractions larger
than approximately 3.5 mL because the capacity of the collection vials is 4 mL. Nonetheless,
compound recoveries are good for both hexane with 50 percent diethyl ether (Table 39) and
hexane with 10 percent acetone (Table 40) and the method reproducibility is acceptable.
Additional work is needed to fully evaluate the ASPEC system.
68
-------
REFERENCES
1. Test Methods for Evaluating Solid Waste; Laboratory Manual — Physical/Chemical
Methods, SW-846, 3rd Edition, Vol IB, U.S. Environmental Protection Agency,
Washington, DC, November 1986.
2. Lee, H. B., Weng, L. D., and Chau, A.S.Y., "Chemical Derivatization Analysis of Pesticide
Residues, IX, Analysis of Phenol and 21 Chlorinated Phenols in Natural Waters by
Formation of Pentafluorobenzyl Ether Derivatives," J. Assoc. Off. Anal. Chem. 67, 1086-
1090, 1984.
3. Lopez-Avila, V., Schoen, S., Milanes, J., and Beckert, W. F., "Single-Laboratory Evaluation
of EPA Method 8080 for Determination of Chlorinated Pesticides and Polychlorinated
Biphenyls in Hazardous Wastes," J. Assoc. Off. Anal. Chem. 41, 375-387, 1988.
4. Viar and Co., Protocol for SAS 4214-QC, November 1988.
5. Lopez-Avila, V., Constantino, F., Milanes, J., and Gale, R., "Single-Laboratory Evaluation
of Method 8060 Phthalate Esters," Final Report for EPA Contracts 6803-3226 and
68-03-3511, Work Assignments 2-14, 3-16, and 0-11, November 1989.
6. Junk, G. A., Avery, M. J., and Richard, J. J., "Interferences in Solid-Phase Extraction Using
C16 Bonded Porous Silica Cartridge," Anal. Chem. 60, 1347-50, 1988.
69
-------
Appendix A
EVALUATION OF SAMPLE EXTRACT
CLEANUP USING SPE CARTRIDGES
LITERATURE REVIEW
-------
TABLE OF CONTENTS
Section Page
1 INTRODUCTION A-1
2 SPE CARTRIDGE TECHNOLOGY A-2
2.1 SPE CARTRIDGES A-2
2.2 APPARATUS FOR HANDLING MULTIPLE SPE CARTRIDGES A-4
2.3 AUTOMATED DEVICES A-4
3 SPE TECHNIQUE A-10
4 APPLICATIONS A-15
REFERENCES A-26
ill
-------
FIGURES
Number
A-l SPE cartridge
A-2 Analytichem International SPS24 and original VacElut manifold. Figure taken
from Analytichem International brochure on SPE cartridges ............... A-5
A-3 J&W SPE vacuum manifold. Figure taken from J&W Scientific brochure on
SPE cartridges ................................................. A-6
A-4 Visiprep vacuum manifold. Figure taken from 1989 Supelco chromatography
catalog 27 [[[ A-7
A-5 VacElut SPS24. Figure taken from Analytichem International brochure on
SPE cartridges ................................................. A-8
A-6 Building method file and BenchMate Workstation. Figure taken from Zymark
brochure on the BenchMate system ................................. A-9
A-7 SPE technique ................................................. A-10
A-8 Types of interactions between the analyte and adsorbent. Figure taken from
Reference 18 .................................................. A-14
A-9 Separation of standard compounds on silica cartridges (3 mL). Figure taken
from Reference 3 .............................................. A-21
A-10 Separation of standard compounds on C18-cartridge (3 mL). Figure taken
-------
TABLES
Number Page
A-l Guide to Selecting SPE Cartridges for a Particular Application A-12
A-2 Summary of Extract Cleanup Procedures that Employ SPE Cartridges A-16
A-3 Recoveries of Pesticides from Lake Sediment Using Extraction Solvent and SPE
Cartridge Combinations A-18
A-4 Percent Recoveries of the Aroclors Using Florisil and Silica Cartridges A-19
A-5 Recoveries of Pesticides from Different Sediment Types Using Acetonitrile as
Extraction Solvent and the Cis SPE Cartridges with the Methylene Chloride/
Acetonitrile/Hexane (50:3:47) Elution Mixture A-20
A-6 Percent recoveries of 21 Organophosphate Pesticides from Diol Cartridges .... A-24
A-7 Extraction and Cleanup of Triazines from Soil, Muscle Tissue, and Corn Oil . . A-25
-------
SECTION 1
INTRODUCTION
This literature review report summarizes the relevant literature published recently on
the use of solid-phase extraction (SPE) cartridges in environmental analysis. The literature
review was performed using the computerized Chemical Abstracts search. Furthermore, issues
of Analytical Chemistry, the Journal of Chromatography, the Journal of Chromatographic
Science, the Association of Official Analytical Chemists Journal, the Journal of High Resolution
Chromatography, the LC»GC Magazine, and the Chromatographia, from 1984 to 1989, were
searched to gather references that were not retrieved during the Chemical Abstracts search.
Fourteen articles (References 1 through 14) were judged to be scientifically relevant to
the objectives of this study and were retrieved from the literature. Other references
(References 15 through 28) were also retrieved, because they were dealing with the use of SPE
cartridges in preconcentrating organics from water samples or other applications. However, they
were not summarized in this literature review when the information presented in these
references did not deal specifically with extract cleanup/fractionation.
The literature review summary presented in this report addresses the following:
• The SPE cartridge technology and apparatus needed for sample processing using
the SPE cartridge
• The SPE technique
• Applications.
A-l
-------
SECTION 2
SPE CARTRIDGE TECHNOLOGY
2.1 SPE CARTRIDGES
A typical SPE cartridge consists of a polypropylene syringe body with a barrel-type
cartridge, two polyethylene frits (20-/im pores) or stainless steel frits, and the adsorbent material
(Figure A-l). Typical volumes are 1 mL, 3 mL, and 6 mLthat accommodate 100 mgto 2000 mg
adsorbent material. The average capacity is approximately 5 percent of adsorbent mass, or
5 mg/100 mg of adsorbent. A Luer tip allows easy attachment of the cartridge to adapters,
stopcocks, and vacuum manifolds or workstations. Large reservoir capacity (LRC) columns are
available for processing larger-volume samples. Figure A-l shows various types of cartridges
that are available commercially.
Silica-gel-filled cartridges and silica-based bonded-phase cartridges seem to dominate
the market, but polymeric cartridges are also getting quite popular. Interaction Chemicals of
Mountain View, California, has developed a line of polymeric materials known as Polysorb
MP-1, MP-2, MP-3 polymers that are spherical, porous, and crosslinked and are based on
styrene-divinyl benzene or vinyl pyridine. The MP-1, MP-2, and MP-3 can be used to remove
large amounts of fats, waxes, hydrocarbons, and surfactants from complex matrices. MP-2 and
MP-3 can be used in either charged or noncharged mode; thus, their capacity depends upon
solvent pH. Polysorb packings have 35-fim particles and have a narrow particle size distribution.
Their capacity is approximately 100 /ig per 100 mg packing. The polymer can be used over a
pH range of 0 to 14. Solvents such as methanol, acetonitrUe, and tetrahydrofuran can be used
in any amount to condition, process, or elute samples. Hydrocarbons and chlorinated solvents
can also be used, but these may swell the polymer, causing slightly slower elution times. Finally,
one other advantage of these polymeric materials is that they can be reused. These polymers
are chemically stable and can be washed with strong acid or base to completely remove any
materials left on the cartridge. The number of times the cartridges can be reused depends on
the sample matrix and the instrument sensitivity.
A unique SPE phase Cyclobond I was developed by Astec, Whippany, New York. This
adsorbent material is prepared by covalent coupling of /3-cyclodextrin to 40-/im silica particles.
The /3-cyclodextrin has a toroid structure with seven glucose units; the primary and secondary
hydroxyls are outside the cavity, while the internal void is hydrophobia The hydrophobia part
of the analyte enters this cavity and is held by electrostatic attraction. No preconditioning of
the Cyclobond I cartridge is needed because the surface is hydrophilic.
The SPE cartridges are available from various manufacturers (e.g., J. T. Baker Inc.,
Supelco, Burdick & Jackson, AUtech, Analytichem International, J&W Scientific Inc., etc.).
Additional information can be found in Reference 1.
A-2
-------
RESERVOIR — HIGH QUALITY. MEDICAL —
GRADE POLYPROPYLENE MINIMIZES
INTERFERENCE FROM PLASTICIZERS.
BONDESL (SEPRALYTE) SORBENT —
HIGH CAPACITY. GO ANGSTROM
POROSITY BONDED SILICA SORBENTS.
40 MICRON MEAN PARTICLE SIZE FOR -
OPTIMAL FLOW RATES.
UPPER AND LOWER FRITS — 20 (un
POROSITY POLYETHYLENE
• STURDY DOUBLE-RIDGED LIP
PROVDES A CONSISTENT SEAL
WHEN USED WITH ROBOTIC
WORK STATIONS
WIDE 5/8-INCH OPENING FOR
EASE OF AUTOMATED ALIGNMENT
AND SAMPLE INTRODUCTION
• LARGE 10 mL POLYPROPYLENE
RESERVOIR
LUER TF — EASIY ATTACHED TO -
ADAPTERS, STOPCOCKS AND VAC
ELUT OR VAC ELUT SPS 24 SAMPLE
PROCESSING STATION.
-RESERVOIR
ANALYTICHEM CARTRIDGE
BONDESIL (SEPRALYTE) SORBENTS
STANDARD FRITS ARE POLYETHYLENE
20 |im POROSITY
LUER TIP IS EASILY ATTACHED TO
ADAPTERS. STOPCOCKS AND SAMPLE
PROCESSING STATIONS
UPPER
FRIT
SPE
PACKING
LOWER
FRIT
POLYPROPYLENE
HOUSING
INTERACTION
CHEMICALS CARTRIDGE
FEMALE
LUER
NLET
MALE
LUER
OUTLET
POLYTHYLENE
FRIT
PACKING
MATERIAL (0.5 mL)
ALLTECH CARTRIDGE
Figure A-l. SPE cartridge.
-------
22 APPARATUS FOR HANDLING MULTIPLE SPE CARTRIDGES
Several devices are available for handling multiple cartridges. They include the VacElut
SPS24 (Analytichem International) that can handle up to 24 cartridges simultaneously, the
original VacElut from Analytichem International that handles up to 10 cartridges (Figure A-2),
J&W's SPE Vacuum Manifold for 20 cartridges (Figure A-3), the Visiprep Vacuum Manifold
from Supelco Inc. for 12 cartridges (Figure A-4), Alltech's 12-port manifold, Adsorbex SPU
24-port vacuum manifold from EM Science, the Baker-10 SPE and SPE-21 systems (J. T. Baker),
and Spe-ed Mate-10 or Spe-ed Mate-30 of Applied Separations.
In general, a vacuum manifold consists of a heavy-duty glass basin that will not discolor,
fog, or dissolve when exposed to organic solvents such as tetrahydrofuran. The Analytichem and
the EM Science devices have two operating positions that allow a switch to be made between
the waste and the collect steps in a matter of seconds. Replaceable stainless steel sample
delivery tips provide the cleanest possible extracts, and a series of collection racks allows use of
the appropriate collection vials. A built-in vacuum bleed valve and gauge is part of the manifold
and a vacuum trap consisting qf a 500-mL or larger vacuum flask, 1/4-inch vacuum tubing, and
a vacuum source are needed to operate the system. Individual valves on the Visiprep vacuum
manifold cover allow precise control of the flow through the cartridges.
Another interesting device that is available commercially is the Visidry Drying
Attachment from Supelco Inc. This device is attached to the vacuum manifold and can dry up
to 12 cartridges simultaneously, or it can evaporate solvent from up to 12 fractions at one time
in the same containers. Gas flow to each tube can be independently adjusted, preventing sample
loss through splashing.
A detailed diagram of a vacuum manifold is shown in Figure A-5.
23 AUTOMATED DEVICES
We had the opportunity to see three of the automated devices that are available
commercially for processing samples prior to analysis. These devices include: the Millilab
Workstation (Waters), the BenchMate (Zymark Corp), and the ASPEC (Gilson Medical
Electronics Inc). Each of these devices will be described in detail below. Another system, the
Advanced Automated Sample Processor (AASP), was developed by Analytichem International
and is currently marketed by Varian Associates. This is the first device for automated SPE;
however, the system is considered only semiautomated because the sample is loaded off line.
Ten cassettes consisting of 10 sample cartridges each can be processed with this system at a time.
When the cartridge is clamped in a compression chamber, it becomes part of the HPLC
flowstream and is placed on line with the HPLC column.
The Millilab workstation consists of two modules, a transport system, and a fluidics
module (15). The transport module consists of a robotic arm moving in the x, y, and z directions
and has a probe with a double-walled tube joined by an inflatable tip. The tip fits into a female
Luer fitting on the cartridge, taking hold or releasing the cartridge by inflating or deflating.
Cartridges, samples, and receiving tubes are positioned on the work surface of the transport
module in racks with preset coordinates that are retained in the memory of the control system.
The fluidics module provides the necessary solvents, sensor controls, and the external
communication interfaces. Two standard test tube sizes are used with this workstation: 16 mm x
100 mm with a capacity up to IS mL, and 10 mm x 75 mm with a capacity up to 4 mL. Racks
are available that hold 84 of the larger size or 120 of the smaller size tubes.
A-4
-------
\ \ \
JT_rh_rT—rh_rt_7n
-n
In the '\\ASTE' position.
column conditioning and
waste solvents flou
through a I'NIQl'E
WASTE DIVERSION
FUNNEL to an external
vacuum trap, keeping (he
sample collection area clean.
Place thumbs on tabs and
lift lid with ringers.
Rotate lid to the
'COLLECT' position.
In the'COLLECT
position, the sample
delivery tips direct the
purified eluant into the
sample collection tubes
with NO CROSS-
CONTAMINATION.
Figure A-2. Analytichem International SPS24 and original VacElut manifold. Figure taken
from Analytichem International brochure on SPE cartridges.
A-5
-------
A variety of reservoirs,
stopcocks and adapters
are available
^ ^
p p
Removable stainless steel
olvent guides
f
A rugged
polypropylene
basin
Two position coyer
simplifies extraction
and elution steps
Built-in vacuum gauge
and bleed valve
Clear, chemical resistant
window allows visual
inspection during
extraction
Figure A-3. J&W SPE vacuum manifold. Figure taken from J&W Scientifk brochure on SPE
cartridges.
A-6
-------
Smart Sup*icH»"Tub«!
Configurations for Using Sup«lclean Tubes
with the Visiprep" Vacuum Manifold*
A Supelclean tub* can M
,o.n«d to a 20ml (Cat No
5-7021) Of 60ml (Cat No
5-7022) reservoir, a 1ml
(Cat No 5-7023) Of 3rrt
(Cat No 5-7024) Wtrition
tube, or another Supetctoan
tube via an adaptor (Cat No
5-70201
Visidry
Drying Attachment*
(Cat No. 5-7100)
V«ipr«p Solid Phase
E "traction Vacuum Manifold
tCai No 5-7030)
»Pa«M Pending *US Pit No D 289.861
Figure A-4. Visiprep vacuum manifold. Figure taken from 1989 Supelco chromatography catalog 27.
A-7
-------
Position Indicator
\ Stainless Steel Delivery Tips
8. ] Lift Tab
Lift Tab
Upper Lid
13.) Silicone Ud Seal
(Upper Ud Seal)
7.) 24-Place Molded Cover
©
WASTE COLLECT
Waste Funnel
18.) Foam Base Seal
(Lower Ud Seal)
Collection Vials
5.) Collection Rack
r*"i
/
\
—
.
1— i
~
IJ
— I
/
20.) Waste Tower
^v
21.] Elastic Lid Fastener
©
Vacuum Release Knob
3.) Glass Vacuum Basin —
2. j Lid Fastener Anchors.
Vacuum Hose Fitting
NAC ELUT SP5 24
I
WARNING: If glass is
damaged m any way. do not
use Contact Analytichem or
your distributor
[22.) Vacuum Control/
Needte Valve
Figure A-5. VacElut SPS24. Figure taken from Analytichem International brochure on SPE
cartridges.
A-8
-------
The BenchMate Workstation Model B220 with liquid management system, membrane
filtration, solid-phase extraction, and HPLC injection is similar to the Millilab Workstation. The
system can use up to six solvents and works only with syringe-barrel-type cartridges. Delivery
of liquids is achieved by precision syringes through a unique 12-port valving technology. The
capacity of the BenchMate is 50 tubes/rack x 4 racks (tube size 16 x 100-mm). It can be used
with 200-mg and 500-mg cartridges.
The BenchMate can be operated either in Autostart or Personal Computer (PC) control
mode. In the Autostart mode, the method is set up and saved to a disk on an off-line PC; the
disk is then loaded into the BenchMate Workstation, and the Autostart button is depressed. In
the PC control mode, an IBM-compatible PC is connected to the workstation, and the method
is set up on the PC. To set up a method to run on the BenchMate Workstation, a series of
menu screens prompt for information such as the type of operations, their sequence, number of
samples, transfer volumes, solvent addition volumes, etc. Figure A-6 exemplifies how to build
a method with the BenchMate Workstation.
Another workstation, ASPEC from Gilson, also uses an x, y, and z robot-like arm for
adding samples, conditioning cartridges (100 mg and 500 mg), and collecting fractions. The
system uses positive pressure (2 to 3 psi) to push solvent through the cartridge. The system is
compatible with most standard disposable cartridges, can process a maximum of 108 samples
without operator intervention, and can accommodate up to 5 different solvents for maximum
selectivity. ASPEC software allows the selection of the proper volume and flowrate for each
solvent used in cartridge preconditioning, elution, rinsing, etc., and can choose between a
sequential and a batch mode of operation.
The complexity of the systems that are available commercially appears to have slowed
their acceptance rate. The few laboratories we have talked to indicated that considerable capital
investment, setup time, and need for a skilled chemist to operate this type of equipment are
required, and that these factors make the use of these systems very expensive. Nonetheless, we
feel that automation of the labor-intensive sample preparation step is much needed.
TUM en*>TCN
™«®Br
WTMOOi .
04 Can
BUI1TOCOU1CT
j mwMifiowrt
!•>< <&»**• mt~m*iimm*<*t:T
Figure A-6. Building method file and BenchMate Workstation. Figure taken from Zymark
brochure on the BenchMate system.
A-9
-------
SECTION 3
SPE TECHNIQUE
The SPE technique utilizes the principle of selective retention of compounds from a
liquid matrix onto a solid adsorbent. The elution conditions for the SPE cartridges are typically
chosen so that the target analytes are retained onto the adsorbent while the coextracted
materials are washed off from the cartridge with the eluent. Alternatively, the coextracted
materials are retained while the target analytes are eluted from the cartridge. Figure A-7
outlines the steps involved in this process.
The SPE technique is useful in two general areas: in the removal of matrix interferents
that might interfere with the determination of the target analytes, and in trace enrichment. The
former application which has had very limited evaluation is of interest to this study; the latter
application has been dealt with for some time, and there are numerous reports on this subject
IT
V
v
• •
V
V
V
CONDITIONING
Conditioning the
sorfaentpriorto
sample application
ensures repro-
ducible retention
of the compound
of interest (the
isolate)
RETENTION
• Adsorbed isolate
• Undesired matrix
constituents
A Other undesired
matrix
components
RINSE
A Rinse the
columns
to remove
undcsired
matrix
components
ELUTION
> Undesired
components
remain
I Purified and
concentrated
isolate ready
foranalvsis
Figure A-7. SPE technique.
A-10
-------
matter (16-27). Applications reported for the removal of matrix interferents include those using
Florisil, alumina, and silica gel. Applications reported for trace enrichment include mostly
bonded-phase silicas, of which C18-bonded silica has had the largest number of applications.
Cartridges available commercially for trace enrichment are shown in Table A-l.
Junk et at. (28) performed procedural blanks on the SFE cartridges to establish the
background levels of organic contaminants. Experimental data reported by Junk et al. (28)
indicated the presence of alkanes, alkenes, various plasticizers and antioxidants; the levels of
these contaminants varied from lot to lot. Hence, these cartridges must be checked for
background contamination prior to use.
Some of the potential pitfalls with the SPE technique are associated mainly with the
adsorbent material, although the eluent cannot be totally ignored. Differences in bonded-phase
materials purchased from different manufacturers can cause changes in compound elution
patterns and recoveries. If a method is not rugged then conditions should be chosen that may
allow some leeway in both solvent and bonded-phase composition (23).
Essentials of the SPE technique are:
• Conditioning of the cartridge prior to the application of the sample is needed to
remove contaminants due to packaging and handling processes and to activate the
packing. Conditioning will leave the adsorbent material in a state that is
compatible with the loading solvent and the analytes of interest. To ensure that
the packing does not get dry between conditioning and sample addition, about
1 mm of the conditioning solvent should remain on the upper frit. If the packing
gets dry, the conditioning procedure must be repeated.
• In the loading step, the sample is passed through the cartridge, and the analytes
of interest are retained by the adsorbent material. For the analytes to be retained
by a polar adsorbent, the solvent in which they are dissolved must be relatively
nonpolar. For example, in case of alumina, Florisil or silica cartridges, which
contain polar materials, the analytes are dissolved in hexane, which is a nonpolar
solvent. In the case of C^-bonded silica, which is a nonpolar adsorbent, the
analytes must be dissolved in an aqueous solution in order for the C18-bonded
silica to retain them.
• In the rinsing step, undesirable sample components are washed off, leaving the
target analytes on the cartridge. This step is not always performed, especially
for multiresidue analysis, since some target compounds may be washed off with
undesirable sample components.
• Cartridge elution is typically performed with 5 to 10 bed volumes of solvent. The
bed volume per 100 mg adsorbent of 40-pm particles with 60-A pores is
approximately 120 liL. Therefore, the optimal solvent volume for a 500-mg
cartridge is 0.6 to 12 mL. The solvent volume should be kept to a minimum to
minimize elution of undesirable sample components. This means that solvent
polarity should also be taken into consideration. Furthermore, when different
solvents are considered for cartridge elution, each solvent that is passed through
the cartridge must be miscible with the prior solvent.
A-ll
-------
TABLE A-l. GUIDE TO SELECTING SPE CARTRIDGES FOR A PARTICULAR APPLICATION
10
Nonpolar
extraction
PoUr
extraction
Cation exchange
extraction
Anion exchange
extraction
CovaletH
extraction
Bondelut
C18 -- Octadecyl
C8-Odyl
C2 ~ Ethyl
CH - Cyclohexyl
PH - Phenyl
CN - Cyanopropyl
CN — Cyanopropyl (endcapped)
CN — Cyanopropyl
20H-Dk>l
SI -- SUica
NH2 - Aminopropyl
PSA - Primary/secondary amine
SCX ~ Benzenesulfonic acid
(Strong)
PRS ~ Propylsulfonic acid
(Stong)
CBA ~ Carboxylic add (weak)
SAX - Quaternary amine
(Strong)
PSA - Primary/secondary amine
NH2 — Aminopropyl (weak)
DBA - Diethylaminopropyl (weak)
PDA - Phenyiboronic acid
Analyte
functional
groups
Hvdrophohic groups
Aromatic rings
Alkyl chains
Hydrophilk groups
Hydroxyls
Amines
Heteroatoms (S,O,N)
Cations
Amines
Pyrimidines
Anions
Carboxylic acids
Sulfonic acids
Phosphates
Vicinal diols
Matrix
Aqueous
Water
Buffers
Biological fluids
Nonpolar
Hexane
Oils
Chloroform
Lipids
Aqueou^
Water
Acidic buffers
Biological fluids
Auueous
Water
Alkline buffers
Biological fluids
Aqueous
Alkaline buffers
Biological fluids
Typical
edition
solvents
Methanol
Acetonitrile
Ethyl acetate
Chloroform
Acidic methanol
Hexane
Methanol
Isopropanol
Acetone
Alkaline buffer
High ionic
strength buffer
Acidic buffer
High ionic
strength buffer
Acidic methanol
Typical
applications
Drugs of abuse
PepliJcs
Pesticides
Therapeutic
Drug monitoring
Vitamin D
Metabolites
LJpid separations
Oil additives
Carbohydrates
Phenols
Catecholamines
Herbicides
Pharmaceuticals
Organic acids
Vitamins
Fatty acids
Phosphates
Nucleolides
Nucleosides
Carbohydrates
Calecholamines
•Data taken from Anarytkhem International brochure on SPE cartridges.
-------
In developing a method involving the SPE technique, consideration must be given
to the properties of the analyte, the adsorbent, and the sample matrix. The
analyte could interact with the adsorbent through hydrogen bonding, electrostatic
interaction, and van der Waals forces. Hydrogen bonding may occur when
functional groups such as carbonyl, amino, and hydroxyl are present. Electrostatic
interaction may occur when there are sulfonates, carboxylates, and amines present.
van der Waals forces or dispersive interactions occur among altyl and aromatic
groups. Figure A-8 outlines some of these interactions.
The matrix plays a very important role in the method development. The overall
characteristics of the matrix need to be defined (e.g., is it aqueous or organic
solvent; major constituents such as lipids, surfactants, pigments, etc. need to be
identified.) Once the major constituents are identified, then the particular
adsorbent that will differentiate between the interferents and the analyte needs
to be selected.
A-13
-------
NON-POLAR INTERACTIONS
Sortents Interactions
C8.
PH:
CH:
PRS.
SAX:
t * *
ODO
VANDERWAALS
VANDERWAALS
VAN DER WAALS
CN: V—I
NH,:
20H: j—I
POLAR INTERACTIONS
Sorbcnt* Interaction*
DIPOLE/DIPOLE
HYDROGEN-BONDING
HYDROGEN-BONDING
IONIC INTERACTIONS
Sorbcnt* Interaction*
^ * ELECTROSTATIC
C8A: SI •
ELECTROSTATIC
ELECTROSTATIC
sex.
"
MULTIPLE INTERACTIONS
Interaction*
ELECTROSTATIC.
Non-POLAR
All bonded sUieu otfiibrt polv inttrsctions
due to tr» polar iMea «*«»»
Figure A-8. Types of interactions between the analyte and adsorbent Figure taken from
Reference 18.
A-14
-------
SECTION 4
APPLICATIONS
Table A-2 summarizes the various applications of the SPE cartridge technology for
extract cleanup as reported in the listed references.
The SPE technique was applied to the cleanup of sediment and fish tissue extracts
containing organochlorine pesticides and organophosphorus pesticides (2). Cartridges containing
500 mg Florisil, C18-bonded silica, or silica were employed. Florisil cartridges were used in the
cleanup of lake sediment extracts in hexane, and C18-bonded silica cartridges were used in
cleanup of lake sediment extracts in acetonitrile. The results shown in Table A-3 indicate that
hexane in combination with Florisil cleanup is a poor choice, since recoveries of gamma-BHC,
chlorpyrifos, dieldrin, DDE, and DDT are less than 32 percent. Methylene chloride-acetonitrile-
hexane (50:3:47) was the solvent of choice in eluting the organochlorine pesticides from the C18-
cartridge (Table A-4), and there seemed to be no matrix effects when extracts of loamy fine
sand, organic detritus, or very fine sand were processed through the cartridge (Table A-5).
Both silica and Clg-bonded silica were used to fractionate petroleum hydrocarbons
according to their polarity (3). Very polar oil components, such as asphaltenes, were retained
on the silica cartridges when hexane, dichloromethane, and isopropanol were used as the eluting
solvents. The separation characteristics of the C18-bonded silica are different from those of the
silica. For example, the aromatic compounds are eluted from the silica cartridges in the first
fractions, and the aliphatic compounds are eluted later (Figures A-9 and A-10). The C18-phases
are sensitive to substituent effects. For example, one to two additional methyl groups have about
the same increasing effect on the retention as has an additional ring annellation (3).
Florisil and C18-bonded silica cartridges were used successfully to clean up extracts of
plant material containing chlorthalonil, endosulfan I, endosulfan II, and captan (4). Of the two
types of cartridges, Florisil gave the higher recoveries under the conditions used.
C18-bonded silica and aminopropyl-bonded silica were used in tandem to clean up
extracts obtained from marine sediment and animal tissue (5). The C^-bonded silica retained
lipids and long-chain hydrocarbons, while the aminopropyl cartridge retained amines and organic
acids. The effect of column order was not evaluated; however, the authors reported that the ion
exchange capacity of the aminopropyl-bonded silica was reduced by any nonpolar material in the
sample extract if it preceded the C18-cartridge.
A quick cleanup method for waste solvents was reported by Pedersen and Higgins (6).
A sample of a waste solvent was diluted with hexane and applied to a 350-mg Florisil column.
A major portion of the PCBs and most organochlorine pesticides passed through. Dieldrin,
endosulfan, and endrin were retained on the Florisil column and were recovered with
hexane/methyl-isobutyl ketone (94:6).
A-15
-------
TABLE A-2. SUMMARY OF EXTRACT CLEANUP PROCEDURES THAT EMPLOY SPE
CARTRIDGES
o
Compound Matrix Extraction solvent
gamma-BHC Sediment Acctonitrile
chloropyrifos Fish tissue Hexane
Dieldrin
DDE
DDT
AUcanes Crude oil Hexane
Alkenes
Benzenes
2-Ring aromatics
3-Ring aromatics
4-6 Ring aromatics
Asphaltenes Hexane
Cholesterol
Fatty acid esters
Phthalate esters
Chlofthalonil Plant material Acetone
EndosulfanI
Endosulfan II
Captan
PAHs Marine sediment Acetonitrile
Organochlorine pesticides Animal tissue
Organochlorine pesticides Waste solvent Hexane or hexane/methyl
isobutyl ketone (50:50)
PCBs Transformer oil Isooctane
SPE cartridge
C,,-bondcd silica
Florisil
Silica
C,,-bonded silica
Florisil
C,,-bonded silica
C,,-bonded silica
in series with
aminopropyl-bonded
silica
Florisil
Florisil
Eluting solvent
Meihylcnc chloride/ acetonitrile/hexanc
(50:3:47)
Hexane
Methylene chloride/hexane
Methylene chloride/ isopropanol
Acetonitrile/water (9:1)
Isopropanol/acetonitrile
Isopropanol/hexane
Hcxanc/diethyl ether (1:1)
Acetonitrile
Acetonitrile
Hexane/methyl isobutyl ketone (94:6)
Isooctane
Reference
2
3
3
4
4
5
6
7
(continued)
-------
TABLE A-2. (Concluded)
Compound
Pentachlorophenol
Porybrominated biphenyls
Chlorinated hydrocarbons
phthalate esters
Carbofuran
Metalaxyl
Simazine
Organophosphorus
pesticides
Triazines
Matrix
Adipose tissue
Adipose tissue
Sandy loam
sediment
NBS standard
reference
materials (pine
needles, river
sediment, citrus
leaves, coal, coal
flyash)
Soil
-
Soil
Muscle tissue
Corn oil
Extraction solvent SPE cartridge
Hexane Silica
Hexane C,,-bondcd silica
Florisil
Hexane Florisil
Acetone. HCI-KCI buffer, Silica
partitioning with
methylene chloride;
solvent exchange to
benzene
Diol
See Table A-7 SCX
C..-silica
Diol
Elutlng solvent
Hexane/chloroform
Acctonit rile/hexanc
Hexane/diethyl ether (1:1)
Hcxane/acetone (9:1)
Hexane/methylene
chloride (various combinations)
Hcxane/acetone (19:1) Hexane/acetone (1:1)
Hexane
Hcxane/acetone (9:1) Hexane/acetone (8:2)
Acetonitrile/0.1 M K,HPO<
(50:50)
Reference
8
9
10
11
12
13
Organochlorine pesticides Sludge
Methylene
chloride/acetone (50:50)
Florisil
Hexane/diethyl ether (50:50)
14
-------
TABLE A-3. RECOVERIES OF PESTICIDES FROM LAKE SEDIMENT USING
EXTRACTION SOLVENT AND SPE CARTRIDGE COMBINATIONS"
Compound
gamma-BHC
Chlorpyrifos
Dieldrin
DDE
DDT
gamma-BHC
Chlorpyrifos
Dieldrin
DDE
DDT
Extraction solvent Column Eluting solvent
Hexane Florisil Methylene chloride/
acetronitrile/hexane
(50:3:47)
Acetonitrile C18-bonded silica Methylene chloride/
acetonitrile/hexane
(50:3:47)
Percent
recovery
32.3
17.2
20.0
10.5
20.8
87.4
48.6
79.3
76.7
90.8
Data taken from Reference 2.
A-18
-------
TABLE A-4. PERCENT RECOVERIES OF THE AROCLORS
USING FLORISIL AND SILICA CARTRIDGES*
Compound
gamma-BHC
Chlorpyrifos
Dieldrin
DDE
DDT
gamma-BHC
Chlorpyrifos
Dieldrin
DDE
DDT
gamma-BHC
Chlorpyrifos
Dieldrin
DDE
DDT
Eluting solvent
Acetonitrile
Methylene chloride/
acetonitrile/hexane
(50:3:47)
Hexane
Percent
recovery
52.1
17.1
21.6
9.3
30.2
87.4
48.6
79.3
76.7
90.8
81.4
37.3
5.0
78.1
51.3
"Data taken from Reference 2.
A-19
-------
TABLE A-5. RECOVERIES OF PESTICIDES FROM DD7FERENT
SEDIMENT TYPES USING ACETONTTRILE AS
EXTRACTION SOLVENT AND THE C18 SPE CARTRIDGES
WITH THE METHYLENE CHLORIDE/ACETONITRILE/
HEXANE (50:3:47) ELUTION MIXTURE*
Sediment sample Compound
Percent recovery
Loamy
fine
sand
Organic
detritus
Very fine
sand
gamma-BHC
Chlorpyrifos
Dieldrin
DDE
DDT
gamma-BHC
Chlorpyrifos
Dieldrin
DDE
DDT
gamma-BHC
Chlorpyrifos
Dieldrin
DDE
DDT
87.4
48.6
79.3
76.7
90.8
64.5
37.9
58.6
47.3
51.8
75.1
46.1
62.2
66.6
67.3
aData taken from Reference 2.
A-20
-------
Compound class
Alkanes
Alkenes
Benzenes
2-Ring aromatics
3-Ring aromatics
4-6-Ring aromatics
Asphaltenes
Cholesterol
Fatty acid esters
Phthalates
•Cartridge Fl
3-mL column 2 mL
hexane
1-mL column 0.5 mL
hexane
Fl
xxxxxx
xxxxxx
F2 F3
F4 F5
P
w
UJ
xxxxxx
xxxxxx
xxxxxx
xxxxxx
F2
2 mL 10%
methylene
chloride
0.5 mL
hexane
F3
2 mL 20 %
methylene
chloride
1 mL 10%
methylene
chloride
retained
xxxxxx
xxxxxx
xxxxxx
F4 F5
2mL 2mLl:l
methylene methylene chloride/
chloride isopropanol
1 mL lmLl:l
methylene methylene chloride/
chloride isopropanol
Figure A-9. Separation of standard compounds on silica cartridges (3 mL).
Figure taken from Reference 3.
Compound class
I
n
Fl
F2
F2a
Fl
F2
F3
F3
P
o
W
UJ
1-2-Ring arom. with alkyl than above
>6-Ring arom.
xxxxxx
xxxxxx
xxxxxx
xxxxxx
xxxxxx
xxxxx..
xxxxxx.
^n-^12
n-Cj2 to n-C^
>n-C20
Phthalates
"Elution system
I
n
Fl
3.5 mL 9:1
acetonitrile/water
3mL
acetonitrile
depending
F2
3mLl:9
isopropanoV
acetonitrile
3mLl:4
isopropanoV
acetonitrile
xxxxx
xxxxxx
on sidechain
F2a
3 mL 1:1
isopropanoV
acetonitrile
xxxxx
F3
4mLl:l
isopropanoV
hexane
4mL 1:1
isopropanoV
hexane
Figure A-10. Separation of standard compounds on Cls-cartridge (3 mL).
Figure taken from Reference 3.
A-21
-------
The SPE technique was applied successfully to the determination of PCBs in transformer
oil (7). A 0.2-g transformer oil sample was applied to a 500-mg Florisil cartridge prewetted with
500 fiL isooctane. Without this prewetting, approximately 20 percent of PCBs present in the sample
were found to bind irreversibly to Florisil. PCBs were eluted from the Florisil cartridge with five
2-mL portions of isooctane. Dilution of the transformer oil with isooctane prior to loading it to the
Florisil cartridge did not result in improved recoveries. On the contrary, this required additional
silanized glassware (7).
Ansari and Hendrix (8) reported that pentachlorophenol can be separated from human
adipose tissue using silica gel cartridges (300 to 500 mg) and hexane (17 mL). With an
intermediate elution step (hexane/chloroform 1:1,5 mL), recovery of pentachlorophenol increased
to 97 percent; however, more fat was also removed from the cartridge (8). The C18-cartridge was
also evaluated for this application; however, pentachlorophenol could not be resolved from fat when
methanol/water (9:1) was used to elute the C18-cartridge (8).
A similar application was reported by Hu et al. (9) for the cleanup of adipose tissue
extracts containing polybrominated biphenyls. Removal of fat was four times as high with the
C18-cartridge than with the Florisil cartridge. Sequential extraction of adipose tissue extracts
through both cartridges in either sequence removed 94 to 96 percent of the fat and gave recoveries
of 96 to 99 percent for polybrominated biphenyls. In this case, the cartridges were eluted with
40 mL acetonitrile or 10 mL hexane.
Disposable cartridges containing 1 g Florisil were investigated for the cleanup of extracts
obtained from various environmental matrices (10). Elution patterns and recoveries were
determined for 22 chlorinated hydrocarbons and 16 phthalate esters in the presence of interferents
such as corn oil, diesel hydrocarbons, organochlorine pesticides, and chlorinated phenols. Hexane
(5 mL) recovered 18 chlorinated hydrocarbons from the 1-g Florisil cartridge. Collection of a
second fraction from the Florisil cartridge by elution with hexane/diethyl ether (1:1) helped recover
the four BHC isomers that could not be recovered with hexane; however, their elution patterns
were difficult to reproduce, especially when interferents were present. When hexane/acetone (9:1)
was used as eluent, recoveries of the 22 compounds were > 90 percent, except hexachlorobenzene
at 78 percent. The cleanup procedure developed by Lopez-Avila et al. (10) was tested for
chlorinated hydrocarbons with nine environmental matrices, including relatively clean matrices such
as a sandy loam soil and highly contaminated matrices such as Detroit River sediment and Bloody
Run Creek sediment. The results indicated that the cleanup procedure works, regardless of the
complexity of the matrix, and more than two-thirds of the measurements showed recoveries
>75 percent.
Lopez-Avila et al. (10) also reported a Florisil cartridge procedure for the separation of
phthalate esters from organochlorine pesticides with hexane containing 26 percent methylene
chloride. The phthalate esters were retained on the Florisil cartridge while the organochlorine
pesticides were eluted; the phthalate esters were then recovered with hexane/acetone (9:1).
A method for the cleanup of soil extracts containing carbofuran, metalaxyl and simazine
was reported by Getzin et al. (11). In this method, pesticide residues were extracted from soil
with acetone/aqueous buffer (9:1) at pH 2, and then partitioned into methylene chloride/carbonate
buffer (pH 10.7). The solvent was then exchanged to benzene. The benzene extract was passed
through a silica cartridge already preconditioned with benzene. Interfering compounds were washed
off with hexane/acetone (19:1), and the pesticides were 'eluted with hexane/acetone (1:1).
A-22
-------
Elution patterns and recoveries of 21 organophosphorus pesticides from a diol cartridge
were reported by Hatcher et al. (12). Seven organophosphorus pesticides, chlorpyrifos, demeton,
disulfoton, fenthion, ethylparathion, phorate, and ronnel were eluted from the diol cartridge with
hexane. Hexane/acetone (9:1) was used to recover azinphos methyl, bolstar, coumaphos, ethoprop,
EPN, malathion, merphos, methyl parathion, and sulfotepp. Dimethoate and fensulfothion required
a more polar solvent (e.g., hexane/acetone 8:2), while monocrotophos and TEPP were not
recovered at all from the diol cartridge (Table A-6).
Triazines were selectively eluted from three different types of cartridges (SCX,
Cjg-bonded-silica, and diol), depending on the sample matrix (13). The procedures are outlined
in Table A-7. A strong cation exchange cartridge (SCX) was used for the soil matrix because soil
contains a large number of charged species that can be selectively retained or eluted by the
benzene-sulfonylpropyl packing. To retain the triazines on the SCX cartridge, they were first
protonated by the addition of 1 percent acetic acid to the extract. The extract was then transferred
to the cartridge. The sulfonyl group of the SCX material is negatively charged and therefore retains
the protonated atrazine. After rinsing the cartridge with 1 percent acetic acid, acetonitrile, water,
and 0.1 M K2HPO4 to eliminate matrix interferents, triazines were eluted with acetonitrile/0.1 M
K2HPO4 (50:50). In the case of the C18-bonded-silica, the lipids were strongly retained by the C18-
chain while the triazines were eluted with methanol. In the case of corn oil cleanup on the diol
cartridge, which is very polar, the triazines will be retained by hydrogen bonding and can be later
eluted with methanol.
Cleanup of sludge samples spiked with organochlorine pesticides was reported by Supelco
researchers (14). The adsorbent material, LC-Florisil, was conditioned with methylene
chloride/acetone (50:50) prior to use, and the packing material was allowed to dry under gentle
vacuum (15 mm Hg) for 3 min. The sludge extract in acetone (with traces of methylene chloride)
was applied to the cartridge and allowed to pass through under gravity only. This was followed by
vacuum drying of the cartridge. The organochlorine pesticides were recovered using three 1-mL
portions of hexane/diethyl ether (50:50). Compounds were recovered quantitatively (recovery
>93 percent), and method precision varied from 4.4 to 12 percent for 12 determinations.
A-23
-------
TABLE A-6. PERCENT RECOVERIES OF 21 ORGANOPHOSPHATE PESTICIDES
FROM DIOL CARTRIDGES*
Compound
Azinphos methyl
Bolstar
Chlorpyrifos
Coumaphos
Demeton
Dimethoate
Disulfoton
Ethoprop
EPN
Fensulfothion
Fenthion
Malathion
Merphos
Monocrotophos
Parathion-ethyl
Parathion-methyl
Phorate
Ronnel
Sulfotep
TEPP
Tetrachlorvinphos
Hexane
4.2
100
123
95
2.5
12
101
29
NDb
100
95
101
ND
Hexane/acetone
(9:1)
100
102
105
107
98
3.0
116
75
101
116
100
Hexane/acetone
(8:2)
55
1.9
60
"Data taken from Reference 12. A 500-mg diol cartridge was used for this
experiment.
bND - not detected.
A-24
-------
TABLE A-7. EXTRACTION AND CLEANUP OF TRIAZINES FROM
SOIL, MUSCLE TISSUE, AND CORN OIL*
Soil:
Extraction:
Precondition:
Load:
Rinse:
Elution:
Muscle tissue:
Extraction:
Precondition:
Load:
Rinse:
Elution:
Corn oil:
Extraction:
Precondition:
Load:
Rinse:
Elution:
500 mg SCX cartridge
100 g soil shaken in 90% acetonitrile
5 mL 1% acetic acid
5 mL filtered extracted diluted with 25 mL 1% acetic acid
2 mL 1% acetic acid
1 mL acetonitrile
1 mL water
1 mL 0.1M K2HPO4
2 mL acetonitrile/0.1 M K2HPO4(50:50)
500 mg Cu cartridge
100 g tissue homogenized in 100 mL methanol
5 mL methanol
5 mL water
5 mL filtered extracted diluted with 50 mL water
2 mL water
2 mL methanol
500 mg diol cartridge
None
5 mL methanol
5 mL hexane
5 mL corn oil diluted with 50 mL hexane
2 mL hexane
2 mL methanol
"Data taken from Reference 13.
A-25
-------
REFERENCES
1. Majors, R. E., "New Devices and Instrumentation for Sample Preparation in Chromatog-
raphy," LC-GC 7(2), 92-96, 1989.
2. Marble, L. K., and Delfino, J. J., "Extraction and Solid Phase Cleanup Methods for
Pesticides in Sediment and Fish," American Laboratory 22-32, November 1988.
3. Theobald, N., "Rapid Preliminary Separation of Petroleum Hydrocarbons by Solid-Phase
Extraction Cartridges," Analytica Chimica Acta 204, 135-144, 1988.
4. Bicchi, C, D'Amato, A., Tonutti, I., and Barbina, M. T., "Use of Prepacked Cartridges in
the Clean-up of Plant Material in Residual Pesticide Analysis," Chromatographia 20 (4),
219-222, 1988.
5. Ozretich, R. J., and Schroeder, W. P., "Determination of Selected Neutral Priority Organic
Pollutants in Marine Sediment Tissue, and Reference Materials Utilizing Bonded-Phase
Sorbents," Anal. Chem. 58, 2041-2048, 1986.
6. Pedersen, B. A., and Higgins, G. M., "A Novel Cleanup Technique for Organochlorine
Pesticides and PCBs in a Complex Organic Matrix," LOGC 6(11), 1017-1018, 1988.
7. The Supelco Reporter, "Solid Phase Extraction of PCBs from Transformer Oil,"
Volume VII, No. 4, July 1988.
8. Ansari, G. A. S., and Hendrix, P. Y., "Rapid and Convenient Separation of
Pentachlorophenol from Human Fat Using Silica Sep-Pak Cartridges," J. Chrom. 346,435-
439, 1985.
9. Hu, L. A., Ansari, G. A. S., Treinen Moslen, J., and Reynolds, E. S., "Efficient Clean-up
of Fat Samples by Sep-Pak Cartridges for Polybrominated Biphenyl Analysis," J. Chrom.
241, 419-422, 1982.
10. Lopez-Avila, V., Milanes, J., and Beckett, W. F., "Cleanup of Environmental Sample
Extracts Using Florisil Solid-Phase Extraction Cartridges," J. Chrom. ScL 27,209-215,1989.
11. Getzin, L. W., Cogger, C G., and Bristow, P. R., "Simultaneous Gas Chromatographic
Determination of Carbofuran, Metalaxyl, and Simazine in Soils," J. Assoc. Off. Anal.
Chem. 72, 361-364, 1989.
12. Hatcher, M., Marsden, P., and Taylor, V., "Analysis of Organophosphorus Pesticide by
Capillary GC/FPD and GC/MS," Proceedings of the U.S. EPA Symposium on Waste
Testing and Quality Assurance, Vol. n, p. G-70, 1988.
A-26
-------
13. J & W Scientific, "Extraction of Triazines Using Solid Phase Extraction Cartridges," The
Separation Times 3(1), 4-9, 1989.
14. The Supelco Reporter, "Reliable Solid Phase Extraction Procedure for Low Levels of
Pesticides in Sludge Samples," Vol. Vm, No. 4, 1989.
15. Chladek, E., and Marano, R. S., "Use of Bonded Phase Silica Sorbents for Sampling of
Priority Pollutants in Wastewaters," J. Chrom. Sci. 22, 313-319, 1984.
16. Fallick, I.G., "A New Streamlined Approach to Automated Filtration and Solid Phase
Extraction for Automated Sample Preparation Workstation," J. Anal. Purific. 24-27,
February 1987.
17. Andrews, J. S., and Good, T. J., Trace Enrichment of Pesticides Using Bonded-Phase
Sorbents," American Laboratory 14, 73-75, 1982.
18. Harris, P. A., "Rationale of Method Development," The Second Annual International
Symposium on Sample Preparation and Isolation Using Bonded Silicas, January 14-15,
1985, Philadelphia, PA.
19. Barber, T., "The Use of Bonded and Unbonded Silica for the Rapid Separation of
Additives from Complex Mixtures," The Second Annual International Symposium on
Sample Preparation and Isolation Using Bonded Silicas, January 14-15,1985, Philadelphia,
PA.
20. Wells, M. J. M., and Michael, J. L., "Reversed-Phase Solid-Phase Extraction for Aqueous
Environmental Sample Preparation in Herbicide Residue Analysis," J. Chrom. Sci. 25,
345-350, 1987.
21. Baker, J. T., "Solid Phase Extraction Sample Preparation," 1988.
22. Wolkoff, A. W., and Creed, C, "Use of Sep-Pak CIS Cartridges for the Collection and
Concentration of Environmental Samples," J. Liquid Chrom. 4(8), 1459-1472, 1981.
23. Ferris, I. G., and Haigh, B. M., "A Rapid and Sensitive HPLC Procedure for the
Determination of Atrazine Residues in Soil-Water Extracts," J. Chrom. Sci. 25, 170-173,
1987.
24. Hurst, W. J., "Bonded Solid-Phase Extraction Columns for the Sample Preparation of
Food Materials," LC-GC 6(3), 216-218, 1988.
25. Bardalaye, P. C., and Wheeler, W. B., "Solid-Phase Extraction and Capillary Gas
Chromatographic Determination of Triazine Herbicides in Water," Intern. J. Environ.
Anal. Chem. 25, 105-113, 1986.
26. The Supelco Reporter, "Highly Reproducible Sample Recovery Using Solid Phase
Extraction," Vol. VD, No. 5, September 1988.
27. Sherma, J., "Determination of Organochlorine Insecticides in Waters by Quantitative TLC
and C-18 Solid Phase Extraction," J. Liquid Chrom. 11(9 & 10), 2121-2130, 1988.
A-27
-------
28. Van Home, K. C, "Method Development—Sample Matrix Considerations," The Second
International Symposium on Sample Preparation and Isolation Using Bonded Silicas,
January 14-15, 1985, Philadelphia, PA.
29. Junk, G. A., Avery, M. J., and Richard, J. J., "Interferences in Solid-Phase Extraction
Using C-18 Bonded Porous Silica Cartridges," Anal. Chem. 60(13), 1347-1350, 1988.
A-28
-------
Appendix B
METHOD 3670 - SAMPLE EXTRACT CLEANUP
USING SPE CARTRIDGES
DRAFT PROTOCOL
-------
METHOD 3670
SAMPLE EXTRACT CLEANUP USING SPE CARTRIDGES
1.0 SCOPE AND APPLICATION
1.1 This protocol specifies cleanup procedures using solid-
phase extraction cartridges that contain Florisil, alumina, diol
or silica. These materials are used for general column
chromatography prior to gas chromatographic analysis. Florisil, a
registered trade name of the Floridin Co., is a magnesium silicate
with acidic properties. Alumina is a highly porous and granular
form of aluminum oxide. It is available in three pH ranges (basic,
neutral, and acidic). Silica gel is an amorphous silica with weakly
acidic properties.
1.2 Specific applications: This method includes guidance for
cleanup of sample extracts containing the following analyte groups:
Methods 8080/8081 organochlorine pesticides and polychlorinated
biphenyls, Method 8060 phthalate esters, Method 8120 chlorinated
hydrocarbons, and Method 8040 phenols.
2.0 SUMMARY OF METHOD
2.1 Florisil, alumina, diol or silica solid-phase extraction
cartridges containing 40-um particles (60-A pores) are recommended
for use. These cartridges consist of serological-grade
polypropylene tubes, 6 mL in volume, each packed with 1 g of
adsorbent. The material is held between two polyethylene frits
(20-um pores). Each cartridge is prewashed with 4 mL hexane or
hexane with 10 percent acetone (as specified in this protocol for
various type of cartridges) immediately prior to use. Aliquots of
1 to 2 mL of sample extracts in hexane are loaded onto the
cartridges which are then eluted with suitable solvent(s). A
vacuum manifold is required in order to get reproducible results.
The collected fractions are further concentrated prior to gas
chromatographic analysis.
3.0 INTERFERENCES
3.1 A reagent blank should be performed for the compounds of
interest prior to the use of this method. The level of
interferences must generally be below the method detection limit
before this procedure is performed on actual samples. However,
phthalate esters were detected in Florisil cartridge method blanks
at levels ranging from 10 to 406 ng per cartridge, with 5 phthalate
esters in the 105 to 460 ng range. Complete removal of the
phthalate esters from Florisil and alumina cartridges does not seem
possible.
3.2 More extensive procedures than those outlined in this
method may be necessary for reagent purification.
B-l
-------
4.0 APPARATUS AND MATERIALS
4.1 Vacuum manifold, VacElute Manifold SPS-24 (Analytichem
International) or Visiprep (Supelco, Inc.) or equivalent,
consisting of glass vacuum basin, collection rack and funnel,
collection vials, replaceable stainless steel delivery tips, built-
in vacuum bleed valve and gauge. The system is connected to a
vacuum pump or water aspirator through a vacuum trap made from a
500-mL sidearm flask fitted with a one-hole stopper and glass
tubing.
4.2 Cartridges, Florisil, alumina, diol or silica (40-um
particles, 60-A pores), 1 g; cartridges consist of serological-
grade polypropylene tubes, 6 mL in volume; the adsorbent is held
between two polyethylene or stainless steel frits (20-um pores).
Cartridges of 0.5 g and 2.0 g are also available and could be used,
however, the compound elution patterns need to be verified when
cartridges are used the are different in size from those specified
in this method.
4.3 Kuderna-Danish (K-D) apparatus
4.3.1 Concentrator tube: 10 mL, graduated (Kontes K-
570050-1025 or equivalent). Ground-glass stopper is used to
prevent evaporation of extracts.
4.3.2 Evaporation flask: 500 mL (Kontes K-570001-0500
or equivalent). Attach to concentrator tube with springs.
4.3.3 Snyder column: Three-ball macro (Kontes K-503000-
0121 or equivalent).
4.3.4 Snyder column: Two-ball macro (Kontes K-569001-
0219 or equivalent).
4.4 Muffle furnace.
4.5 Water bath: Heated, with concentric ring cover, capable
of temperature control (±5°C) . The bath should be used in a hood.
4.6 Boiling chips: Solvent-extracted, approximately 10/40
mesh (silicone carbide or equivalent).
5.0 REAGENTS
5.1 Diethyl ether: Pesticide quality or equivalent.
5.1.1 Must be free of peroxides as indicated by EM Quant
test strips (available from EM Laboratories, Elmsford, NY 10523) .
5.1.2 Procedures recommended for removal of peroxides
are provided with the test strips. After cleanup, 20 mL ethyl
alcohol preservative must be added to each liter of diethyl ether.
B-2
-------
5.2 Hexane, acetone, methylene chloride, toluene: Pesticide
quality or equivalent.
6.0 SAMPLE COLLECTION, PRESERVATION, AND HANDLING
6.1 See the introductory material to this chapter, Organic
Analytes, Section 4.1.
7.0 PROCEDURE
7.1 Cartridge Set-up and Conditioning
7.1.1 Arrange the cartridges on the manifold in the
closed-valve position.
7.1.2 Turn vacuum pump on and set pump vacuum to 10
inches of mercury. Do not exceed the manufacturer's recommendation
for manifold vacuum. Flow rates can be controlled by opening and
closing cartridge valves.
7.1.3 Condition the cartridges by pipetting 4 mL hexane
onto each cartridge. Slowly open the cartridge valves to allow
hexane to pass through the sorbent beds to the lower frits. Allow
a few drops per cartridge to pass through the manifold to remove
all air bubbles. Close the valves and allow the solvent to soak the
entire sorbent beds for 5 min. Do not turn off the vacuum.
7.1.4 Slowly open cartridge valves to allow the hexane
to pass through the cartridges. Close the cartridge valves when
there is still at least 1 mm solvent above the sorbent bed. Do not
allow cartridges to get dry. If this happens, repeat the
conditioning step.
7.2 General extract cleanup procedure
7.2.1 Allow extract to reach room temperature if it was
in cold storage.
7.2.2 Inspect the extract visually to ensure that there
are no particulates or phase separations and that the volume is as
stated in the accompanying documents, and verify that the solvent
is compatible with the cleanup procedure. If crystals of sulfur are
visible or if the presence of sulfur is suspected, proceed with
Method 3660.
7.2.3 Pipet 2 mL of extract onto each cartridge. Open
the cartridge valves to allow the extracts to pass through the
cartridge beds at approximately 2 mL/min. When the entire extracts
have passed through the cartridges, but before the cartridges get
dry, rinse the sample vials with additional 0.5 mL solvent portions
and add the rinses to the corresponding cartridges. Close the
cartridge valves and turn off the vacuum after the solvent has
passed through, ensuring that the cartridges never get dry.
B-3
-------
7.2.4 Place clean 5-mL vials or volumetric flasks into
the sample rack corresponding to the cartridge positions.
7.2.5 Attach solvent-rinsed stainless steel solvent
guides to manifold cover and align with collection vials.
7.2.6 Add the first eluting solvent(s) to each
cartridge.
7.2.7 Turn vacuum pump on. Adjust pump pressure to 10
inches of mercury. Allow solvent to soak the sorbent beds for 1 min
or less. Slowly open the cartridge valves and collect eluates into
the collection vials (if the procedure calls for collection of
Fraction 1) or discard.
7.2.8 Close cartridge valves, replace collection vials,
and add the second eluting solvent(s) to each cartridge to collect
Fraction 2. Slowly open cartridge valves and collect eluates.
7.2.9 Bring the total volume of each fraction to 5 mL
by adding additional solvent. If this final volume is too dilute
for gas chromatographic analysis then the fractions collected have
to be concentrated to 1 mL or less, using either nitrogen blowdown
or a micro-Snyder column. Measure the final volumes of the
fractions collected with a syringe.
7.2.10 Transfer the fractions to autosampler vials for
gas chromatographic analysis.
7.3 Organochlorine pesticides
7.3.1 Reduce the sample extract volumes to 2 mL prior
to cleanup. The extract solvent must be hexane.
7.3.2 Use 1-g silica cartridges (whenever
polychlorinated biphenyls are known to be present) or diol
cartridges and perform the steps described in Section 7.1. Hexane
is used to condition the silica cartridges, and hexane with 10
percent acetone is used to condition the diol cartridges.
7.3.3 Add the extracts to the cartridges. Follow step
by step the instructions given in Section 7.2. Silica cartridges
are eluted first with 5 mL hexane to collect Fraction 1 and then
with 5 mL hexane with 50 percent diethyl ether to collect Fraction
2. Diol cartridges are eluted with 10 mL hexane with 10 percent
acetone. Adjust the volumes of the fractions collected to whatever
volume is required (see Method 8081) and analyze. Tables 1 and 2
show compound recoveries for the 1-g silica and the 1-g diol
cartridges, respectively.
B-4
-------
7.4 Phthalate esters
7.4.1 Reduce the sample extract volumes to 2 mL prior
to cleanup. The extract solvent must be hexane.
7.4.2 Use 1-g Florisil or alumina cartridges and perform
the steps described in Section 7.1. Hexane is used to condition
the cartridges.
7.4.3 Add the extracts to the cartridges. Follow step
by step the instructions given in Section 7.2. If organochlorine
pesticides are known to be present in the extract, use Florisil
cartridges. Elute the Florisil cartridges with hexane with 20
percent methylene chloride to remove the organochlorine pesticides.
The phthalate esters are recovered with 10 mL hexane with 10
percent acetone. Alumina cartridges are eluted with 10 mL hexane
with 20 percent acetone. Adjust the volumes of the fractions
collected to whatever volume is required (see Method 8061) and
analyze. Table 3 and 4 show compound recoveries for the 1-g
Florisil and the 1-g alumina cartridges, respectively.
7.5 Chlorinated hydrocarbons
7.5.1 Reduce the sample extract volumes to 2 mL prior
to cleanup. The extract solvent must be hexane.
7.5.2 Use 1-g Florisil cartridges and perform the steps
described in Section 7.1. Hexane is used to condition the Florisil
cartridges.
7.5.3 Add the extracts to the cartridges. Follow step
by step the instructions given in Section 7.2. Florisil cartridges
are eluted with 5 mL hexane with 10 percent acetone. Adjust the
volumes of the fractions collected to whatever volume is required
(see Method 8121) and analyze. Table 5 shows compound recoveries
for the 1-g Florisil cartridges.
7.6 Phenols
7.6.1 Reduce the sample extract volumes to 2 mL prior
to cleanup. The extract solvent roust be hexane.
7.6.2 Use 2-g silica cartridges and perform the steps
described in Section 7.1. Hexane is used to condition the silica
cartridges.
7.6.3 Add the extracts to the cartridges. Follow step
by step the instructions given in Section 7.2. Silica cartridges
are eluted first with 5 mL hexane which is discarded (Fraction 1).
The phenols are eluted with 5 mL hexane with 25 percent toluene.
If smaller cartridges are used, then Fraction 1 cannot be discarded
since it contains some of the phenols. Adjust the volumes of the
fractions collected to whatever volume is required ( see Method
B-5
-------
8041) and analyze. Table 6 shows compound recoveries for the 2-g
silica cartridges.
8.0 QUALITY CONTROL
8.1 Before any samples are cleaned up using the solid-phase
extraction cartridges, the efficiency of the cartridge must be
verified. A recovery check must be performed using standards of
the target analytes at known concentration. Only lots of
cartridges that do meet the recovery criteria for the spiked
compounds can be used to process the samples.
8.2 A check should also be performed on each individual lot
of cartridges and for every 300 cartridges of a particular lot.
9.0 REFERENCES
1. Lopez-Avila, V., Milanes, J., Dodhiwala, N.S., and Beckert,
W.F. "Cleanup of Environmental Sample Extracts Using Florisil
Solid-Phase Extraction Cartridges", J. Chrom. Sci. 27, 209-
215, 1989.
B-6
-------
TABLE 1. PERCENT RECOVERIES AND ELUTION PATTERNS FOR 17
ORGANOCHLORINE PESTICIDES FROM 1-g SILICA CARTRIDGES a
Compound
Fraction 1 Fraction 2
Average Percent Average Percent
recovery RSD recovery RSD
alpha-BHC
gamma-BHC
beta-BHC
Heptachlor
delta-BHC
Aldrin
Heptachlor epoxide
Endosulfan I
4,4' -DDE
Dieldrin
Endrin
4,4' -ODD
Endosulfan II
4,4' -DDT
Endrin aldehyde
Endosulfan sulfate
4,4' -Methoxychlor
Aroclor 1016
Aroclor 1221
Aroclor 1232
Aroclor 1242
Aroclor 1248
Aroclor 1254
Aroclor 1264
0
0
0
97.3 1.3
0
95.9 1.0
0
0
99.9 1.7
0
0
10.7 41
0
94.1 2.0
0
0
0
124
93.5
118
116
114
108
112
98.7
94.8
94.3
0
90.8
0
97.9
102
0
92.3
117
92.4
96.0
0
59.7
97.8
98.0
2.3
1.9
3.0
2.5
2.1
2.3
2.0
2.6
3.3
2.2
2.6
2.1
2.4
Silica cartridges (Supelco,Inc. lot SP0161) were used; each
cartridge was conditioned with 4 mL hexane prior to use. The
organochlorine pesticides were tested separately from PCBs. For
organochlorine pesticides, each experiment was performed in
duplicate at three spiking levels (0.2 ug, 1.0 ug, and 2.0 ug per
compound per cartridge). Fraction 1 was eluted with 5 mL hexane,
Fraction 2 with 5 mL hexane with 50 percent diethyl ether. PCBs
were spiked at 10 ug per cartridge and were eluted with 3 mL
hexane. The value given for PCBs is the percent recovery for
single determination.
B-7
-------
TABLE 2. PERCENT RECOVERIES AND ELUTION PATTERNS FOR 17
ORGANOCHLORINE PESTICIDES FROM 1-g DIOL CARTRIDGES6
Compound
Fraction 1 Fraction 2
Average Percent Average Percent
recovery RSD recovery RSD
alpha-BHC
gamma-BHC
beta-BHC
Heptachlor
delta-BHC
Aldrin
Heptachlor epoxide
Endosulfan I
4,4' -DDE
Dieldrin
Endrin
4,4* -ODD
Endosulfan II
4,4' -DDT
Endrin aldehyde
Endosulfan sulfate
4,4' -Methoxychlor
Aroclor 1260
101
95.0
86.7
96.2
75.9
93.5
98.1
100
97.3
95.2
95.9
97.8
86.0
96.7
19.9
0
90.7
90.0
8.3
8.4
8.5
8.4
8.2
8.1
8.5
9.0
8.3
8.2
9.0
8.9
8.2
8.3
21
8.2
20.4 45
15.4 30
58.9 3.7
80.1 3.9
10.0
Diol cartridges (Supelco, Inc. lot SP0216) were used; each
cartridge was conditioned with 4 mL hexane with 10 percent acetone
prior to use. The organochlorine pesticides were tested separately
from PCBs. For organochlorine pesticides, each experiment was
performed in duplicate at three spiking levels ( 0.2 ug, i.o ug,
and 2.0 ug per compound per cartridge). Each fraction was eluted
with 5 mL hexane with 10 percent acetone. Aroclor 1260 was spiked
at 80 ug per cartridge. The value given for Aroclor 1260 is the
percent recovery for single determination.
B-8
-------
TABLE 3. PERCENT RECOVERIES AND ELUTION PATTERNS FOR 16
PHTHALATE ESTERS FROM 1-g FLORISIL CARTRIDGES3
Fraction 2
Average Percent
Compound recovery RSD
Dimethyl phthalate
Diethyl phthalate
Diisobutyl phthalate
Di-n-butyl phthalate
Bis(4-methyl-2-pentyl) phthalate
Bis (2 -me thoxyethyl) phthalate
Diamyl phthalate
Bis (2 -ethoxyethyl) phthalate
Hexyl 2-ethylhexyl phthalate
Dihexyl phthalate
Benzyl butyl phthalate
Bis (2 -n-butoxyethyl) phthalate
Bis ( 2 -ethy Ihexyl ) phthalate
Dicyclohexyl phthalate
Di-n-octyl phthalate
Dinonyl phthalate
130
88.2
118
121
123
31.9
93.7
82.1
126
62.0
98.3
135
110
106
123
102
52
2.5
16
13
5.7
31
34
19
6.4
15
6.5
34
2.7
3.3
7.0
8.7
Florisil cartridges (Supelco, Inc.) were used; each cartridge was
conditioned with 4 mL hexane prior to use. Each experiment was
performed in triplicate. The spiking level was 500 ng per compound
per cartridge. Fraction 1 was eluted with 5 mL hexane with 20
percent methylene chloride, Fraction 2 with 5 mL hexane with 10
percent acetone. No phthalate esters were detected in Fraction 1.
B-9
-------
TABLE 4. PERCENT RECOVERIES AND ELUTION PATTERNS FOR 16
PHTHALATE ESTERS FROM 1-g ALUMINA CARTRIDGES3
Fraction 1
Average Percent
Compound recovery RSD
Dimethyl phthalate
Diethyl phthalate
Diisobutyl phthalate
Di-n-butyl phthalate
Bis(4-methyl-2-pentyl) phthalate
Bis (2 -methoxyethy 1) phthalate
Diamyl phthalate
Bis(2-ethoxyethyl) phthalate
Hexyl 2-ethylhexyl phthalate
Dihexyl phthalate
Benzyl butyl phthalate
Bis(2-n-butoxyethyl) phthalate
Bis (2-ethylhexyl) phthalate
Dicyclohexyl phthalate
Di-n-octyl phthalate
Dinonyl phthalate
108
129
92.6
107
88.3
92.2
100
101
93.2
113
104
99.5
101
97.2
103
110
4.6
6.6
7.3
5.6
9.8
5.0
6.4
6.3
13
5.4
3.9
4.7
6.1
6.2
7.5
5.2
Alumina cartridges (J.T.Baker) were used; each cartridge was
conditioned with 4 mL hexane prior to use. Each experiment was
performed in duplicate at three spiking levels (40 ug, 80 ug, and
120 ug per compound per cartridge). Fraction 1 was eluted with 5
mL hexane with 20 percent acetone.
B-10
-------
TABLE 5. PERCENT RECOVERIES AND ELUTION PATTERNS FOR 22
CHLORINATED HYDROCARBONS FROM 1-g FLORISIL CARTRIDGES3
Compound
Hexachloroethane
1 , 3-Dichlorobenzene
1 , 4 -Dichlorobenzene
1 , 2-Dichlorobenzene
Benzyl chloride
1,3, 5-Trichlorobenzene
Hexachlorobutadiene
Benzal chloride
1 , 2 , 4-Trichlorobenzene
Benzotrichloride
1 , 2 , 3-Trichlorobenzene
Hexachlorocyclopentadlene
1,2,4, 5-Tetrachlorobenzene
1,2,3, 5-Tetrachlorobenzene
1,2,3, 4-Tetrachlorobenzene
2 -Chloronaphthalene
Pentachlorobenzene
Hexachlorobenzene
alpha-BHC
gamma -BHC
beta-BHC
delta-BHC
Fraction
Average
recovery
95.4
101
100
102
101
98.4
94.8
99.2
99.2
90.0
97.2
103
98.0
98.0
99.2
94.8
104
78.4
100
99.0
95.4
96.8
1
Percent
RSD
2.0
2.3
2.3
1.6
1.5
2.2
2.0
0.8
0.8
6.5
2.0
3.3
2.3
2.3
1.3
1.4
1.5
1.1
0.4
0.7
1.8
2.7
5Florisil cartridges (Supelco, Inc.) were used; each cartridge was
conditioned with 4 mL hexane prior to use. Five replicate
experiments were performed. Spiking level was 1.0 ug per cartridge
for hexachloroethane,hexachlorobutadiene,hexachlorocyclo-
pentadiene, penta- and hexachlorobenzene; 10 ug per cartridge for
tri- and tetrachlorobenzenes, benzal chloride, benzotrichloride,
and the BHC isomers; 100 ug per cartridge for dichlorobenzenes and
benzyl chloride; and 200 ug per cartridge for 2-Chloronaphthalene.
Fraction 1 was eluted with 5 mL hexane with 10 percent acetone.
B-ll
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TABLE 6. PERCENT RECOVERIES AND ELUTION PATTERNS FOR 18 PHENOLS
FROM 2-g SILICA CARTRIDGES9
Fraction 2
Average Percent
Compound recovery RSD
Phenol
2 -Methy Iphenol
3 -Methy Iphenol
4 -Methylphenol
2 , 4-Dimethylphenol
2-Chlorophenol
2 , 6-Dichlorophenol
4-Chloro-3-methylphenol
2
2
2
2
2
2
2
2
2
r 4-Dichlorophenol
,4 6-Trichlorophenol
,3
,4
,3
r3
r3
,3
r3
6-Trichlorophenol
5-Trichlorophenol
5-Trichlorophenol
5 , 6-Tetrachlorophenol
4 , 6-Tetrachlorophenol
4 -Trichlorophenol
4 , 5-Tetrachlorophenol
Pentachlorophenol
74
84
86
82
91
88
90
94
94
97
95
92
92
97
97
72
95
96
.1
.8
.4
.7
.8
.5
.4
.4
.5
.8
.6
.3
.3
.5
.0
.3
.1
.2
5
5
4
5
5
5
4
7
7
6
7
8
8
5
6
8
6
8
.2
.2
.4
.0
.6
.0
.4
.1
.0
.6
.1
.2
.2
.3
.1
.7
.8
.8
asilica cartridges (Supelco, Inc.) were used; each cartridge was
conditioned with 4 mL hexane prior to use. Each experiment was
performed in duplicate at three spiking levels (0.05 ug, 0.2 ug,
and 0.4 ug per compound per cartridge). Fraction 1 was eluted
with 5 mL hexane and was discarded. Fraction 2 was eluted with
5 mL hexane with 25 percent toluene.
B-12
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