PB85-189918
EPA/600/4-85/020
April 1985
DETERMINATION OF VOLATILE PESTICIDES IN
INDUSTRIAL AND MUNICIPAL WASTEWATERS
by
J.S. Warner, T.M. Engel, P.J. Mondroa, and M.C. Landes
Battelle Columbus Laboratories
Columbus, Ohio 43201
Contract No. 68-03-2956
Project Officer
Thomas Press ley
Physical and Chemical Methods Branch
Environmental Monitoring and Support Laboratory
Cincinnati, Ohio 45268
ENVIRONMENTAL MONITORING AND SUPPORT LABORATORY
OFFICE OF RESEARCH AND DEVELOPMENT
U.S. ENVIRONMENTAL PROTECTION AGENCY
CINCINNATI, OHIO 45268

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TECHNICAL REPORT DATA
(Ptcczc read fnstnja:ons on the reverse before completing)
1. REPORT NO. 2
EPA/600/4-85/020
3. RECIPIENT'S ACCESSION NO.
PB8 5 18 9918 /AS
4. TITLE AND SUBTITLE
Determination of Volatile Pesticides in Industrial
and Municipal Wastewaters
S REPORT OATE
April 1985
6. PERFORMING ORGANIZATION CODE
7. AUTMOH(SI
J.S. Warner, T.M. Engel, P.J. Mondron
and M.C. Landes
B. PERFORMING ORGANIZATION REPORT NO.
9 PERFORMING ORGANIZATION NAME AND ADDRESS -
Battelle Columbus Laboratories
505 King Avenue
Columbus, Ohio 43201
tO. PROGRAM ELEMENT NO.
CBEBIC
11 CONTRACT/GRANT NO.
68-03-2956
12. SPONSORING AGENCY NAME AND ADDRESS
U.S. Environmental Protection Agency
Environmental Monitoring and Support Laboratory
Cincinnati, Ohio 45268
13. TYPE OF REPORT AND PERIOD COVERED
14. SPONSORING AGENCY CODE
EPA/600/06
15. SUPPLEMENTARY NOTES
16. ABSTRACT
A method was developed for the determination of two volatile pesticides,
chloropicrin and ethylene dibromide, in wastewaters. The methods development
program consisted of; a literature review; determination of the extraction
efficiency for each compound from water into cyclohexane; and determination of
suitable gas chromatographic analysis conditions.
The final method was applied to two representative wastewaters spiked at
appropriate levels in order to determine precision and accuracy of the method. For '
a wastewater sample spiked with 5 gg/L of chloropicrin and ethylene dibromide, the
recoveries were 98 ± 12 percent and 69 ± 6.7 percent, respectively. For a
wastewater spiked at 50 yg/L of chloropicrin and ethylene dibromide, the recoveries
were 98 ± 3.3 percent and 108 ± 4.8 percent, respectively. Method detection limits
(MDLs) for the two compounds in distilled water were 0.34 gg/L for chloropicrin and
0.20 Ug/L for ethylene dibromide.. MDLs in wastewaters may be higher due to
interfering compounds.
This report was submitted in partial fulfillment of Contract No. 68-03-2956 by
Battelle Columbus Laboratories under the sponsorship of the U.S. Environmental
Prelection Aaencv. This report covers the oeriod from .lune 1. 1981 r to ,1nnp "W,
il?81, and was completed as of Q§tot^bsLv'd.B82wMENTanalysis
a. DESCRIPTORS
b. 1DENTIF IE RS/GPEN ENDED TERMS
c. COSATI Field/Croup



le. DISTRIBUTION STATEMENT
Release to Public
19. SECURITY CLASS (TIiu Report)
Unclassi fied
21. NO. OP PAGES
49
20 SECURITY CLASS (This page)
Unclassified
22. PRICE
CPA Form 2220*1 (R«v. 4«-H) previous edition is obsolete
i

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DISCLAIMER
The information in this document has been funded wholly or in part by
the United States Environmental Protection Agency under contract 68-03-
2956 to Battelle Columbus Laboratories. It has been subject 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.
ii

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FOREWORD
Environmental measurements are required to determine the quality of
ambient waters and the character of wEste effluents. The Environmental
Monitoring and Support Laboratory - Cincinnati, conducts research to:
.o Develop and evaluate methods to measure the presence and
concentration of physical, chemical, and radiological pollutants in
water, wastewater, bottom sediments, and solid wastes.
o Investigate methods for the concentration; recovery, and
identification of viruses, bacteria and other microbiological
organisms in water; and, to determine the responses of aquatic
organisms to water quality.
o Develop and operate an Agency-wide quality assurance program to
assure standardization and quality control of systems for monitoring
water and wastewater.
o Develop and operate a computerized system for instrument automation
leading to improved data collection, analysis, and quality control.
This report is one of a scries that investigates the analytical behavior
of selected pesticides and suggests a suitable test procedure for their
measurement in wastewater. The method was modeled after existing EPA
methods being specific yet as simplified as possible.
Robert L. Booth, Acting Director
Environmental Monitoring and Support
Laboratory - Cincinnati

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ABSTRACT
A method was developed for the determination of two volatile
pesticides, chloropicrin and ethylene dibromide, in wastewaters. The
methods development program consisted of a literature review;
determination of the extrprtion efficiency for each compound from water
into cyclohexane; and determination of suitable gas chromatographic
analysis conditions.
In order to determine precision and accuracy, the final method was
applied to two representative wastewaters spiked at appropriate levels.
For a wastewater sample spiked with 5 pg/L of chloropicrin and ethylene
dibromide, the recoveries were 98 ± 12 percent and 69 ± 6.7 percent,
respectively. For a wascewater spiked at 50 pg/L of chloropicrin and
ethylene dibromide, the recoveries were 98 ± 3.3 percent and 108 ± 4.8
percent, respectively. Method detection limits (MDLs) for the two
compounds in distilled water were 0.84 pg/L for chloropicrin and 0.20
pg/L for ethylene dibromide. The MDLs in wastewaters may be higher due
to interfering compounds.
This report was submitted in partial fulfillment of Contract Ho.
68-03-2956 by Battelle Columbus Laboratories under the sponsorship of the
U. S. Environmental Protection Agency. This report covers the period
from June 1, 1981, to June 30, 1983, and was completed as of October 1,
1983.
iv

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CONTENTS
Foreword		Ill
Abstract. 			iv
Figures		vi
Tables		vii
1.	Introduction		1
2.	Conclusions 		2
Extraction 		2
Chromatography 		2
Validation Studies 		2
3.	Experimental		3
Extraction 		3
Chromatography 		3
Validation Studies 		3
4.	Results and Discussion		5
Extraction 		5
Chromatography 		5
Validation Studies 		6
References		8
Appendices
A. Volatile Pesticides 		15
v

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FIGURES
Number	Page
1	GC--ECD Chromatogram of 200 ng Chloropicrin and Ethylene
Dibromide (Column 1)		8
2	GC-ECD Chromatogram of 400 ng Chloropicrin and Ethylene
Dibromide (Column 2)		9
3	Analytical Curve for Chloropicrin 		10
A Analytical Curve for Ethylene Dibromide 		11
5	GC-ECD Chromatogram of Cyclohexane Extract of Low Level
Wastewater (a) Unspiked and (b) Spiked With 5 ug/L of
Chloropicrin and Ethylene Dibromide ..... 		13
6	GC-ECD Chromatogram of cyclohexane Extract of High Level
Wastewater (a) Unspiked and (b) Spiked With 50 vig/L of
Chloropicrin and Ethylene Dibromide 		14
vi

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TABLES
Number	Page
1	Recovery of Fumigants from Water		5
2	Data from Minimum Detection Limit Determinations. . .	6
3	Data from Generation of Analytical Curve. ......	7
U	Recovery of Chloropicrin and Ethylene Dibromide from
Wastewaters 		7
vii

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SECTION 1
INTRODUCTION
Chloropicrin and ethylene dibromide are insecticides used for
fumigation of soils and stored grains. The CAS registry number for
chloropicrin is 76-06-02, and its IUPAC name is trichloronitromethane. Its
common synonyms include "Bromofunie", "Dowfume N-8", "Iscobrome D",
"SoiIfume", Aadibroom", "Dowfume W 85", "Nefis", "Sanhyum". The CAS
registry number for ethylene dibroinide is 106-93-4, and its IUPAC name is
1,2-dibromomethane. Its common synonyms include "Acquinite", "Larvacide"
"Microlysin", and "Picfume".
Chloropicrin is produced by the action of hypochlorites on nitronethane
to give a colorless liquid with a molecular weight of 161.4 and a boiling
point of 112.4°C. The compound decomposes violently at high temperatures.
It is nonflammable and chemically inert; its solubility at 0°C is 2.27 g/L
of water. Chloropicrin is a lachrymator and has an LD50 of 250 mg/kg in
rats. A literature survey provided a gas chromatographic (GC) analysis
method using 2% OV-101 and a thermal conductivity detector and a purge and
trap gas chromaographic-mass spectrometric (GC-MS) procedure using a Tenax
GC trap and a Tenax GC column (1). Some electron impact-mass spectrometry
information was found (2). Extraction solvents described included hexane,
ethyl ether, and pentane (3). A spectrophotometry method has also been
used to analyze for this compound (4).
Ethylene dibroraide is produced by the bromination of ethane to give a
colorless liquid with a molecular weight of 187.9 and a boiling point of
131.5°C. It is stable and nonflammable and has a solubility at 30°C of 4.3
g/L of water. The LD50 for this compound is 117-146 mg/kg in rats. Dermal
applications will cause severe burning. A literature survey provided
several extraction solvents: ethyl acetate (5), hexane (6), and benzene (7).
Various analytical methods such as sweep co-distillation, and steam
distillation, were used (8). Gas chromatography-electron capture detector
(GC-ECD) analysis methods were described using a 153! Ucon oil LB-550-X
colunn (5, 9), a 301 DC-200 column (3), and columns of 52 didecyl phthalate ,
52 Carbowax 20M-TPA, and 3% OV-225 (6). Ethylene dibromide has been reacted
with alkali and the resultant brcmide ion was determined by Volhard
titration (7).
Because of the volatilities and solubilities of these compounds, the
selected approach for solvent extraction was similar to that currently being
used by the EPA for determining trihalomethanes in drinking water (10).
Minimum mdifications were required.
1

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SECTION 2
CONCLUSIONS
Chloropicrin and ethylene dibromide are volatile compounds and are not
amenable to standard Kuderna-Danish (K-D) concentration procedures. For
this reason no concentration methods were developed. Since adsorption
column cleanup procedures would involve dilution of the sample, this step
was also eliminated. The final method is included as Appendix A of this
report.
EXTRACTION
A modified version of the EPA Method 501.2 for trihalomethanes in
drinking water gives acceptable results for these compounds and is
familiar to other laboratories. It is, therefore, the extraction method of
choice for chloropicrin and ethylene dibromide.
CHROMATOGRAPHY
Good separation and quantification can be achieved by using GC-ECD and
either of two columns: 1% SP-1000 on Carbopak B or 302 OV-17 on Gas Chroo Q.
Since the IZ SP-1000 on Carbopak B column is already used for two US EPA
methods, 601 and 624, this was chosen as the primary column for the analysis
of these compounds. The 30% OV-17 was presented in the method as a
secondary column.
VALIDATION STUDIES
The MDLs for both compounds were at or below the required 1 vig/I, level.
Analytical curves were constructed for each compound from 10-1000 vg/L;
these were linear over the entire range. Recovery studies were performed on
two relevant wastewaters: one with a high-level background and one with a
low-level background. Neither of the compounds of interest was detected in
these waters. Satisfactory recoveries from both low arid high level spikes
of the chloropicrin and from the high level spikes of the ethylene dibromide
were achieved. Recoveries from the low level spike of the ethylene
dibromide were less than 85 percent, presumably due to some chemical
characteristic of the wastewater used.
2

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SECTION' 3
EXPERIMENTAL
Since chloropicrin and ethylene dibromide are volatile compounds,
K-D concentration and adsorption chroma jgraphy cleanup procedures were
not developed. Literature surveys indicated that both compounds are
stable in water, so stability studies were not performed.
EXTRACTION
The extraction procedure employed was similar to the US EPA Method
501.2 for the determination of triha lomethanes in drinking water. The
sample was poured into a 40-mL centrifuge tube equipped with a
Teflon-lined screw cap to a predetermined 20-mL nark, and its pH adjusted
to 6-8 by addition of 6fi sodium hydroxide or 6N sulfuric acid. Then
four mL of cyclohexane was measured with a four-tnL graduated pipette and
added to the centrifuge tube. The tube was shaken vigorously for one
minute, and the layers were allowed to separate for at least 10 minutes.
Centrifugation was sonetimes necessary to facilitate phase separation. An
aliquot of the cyclohexane layer was withdrawn and analyzed by GC-ECD.
Recovery studies were performed by spiking the reagent water with the
analytes over a range of concentrations, in triplicate at each level, and
determining the percent recovery.
CHROMATOGRAPHY
Five different packed columns were evaluated: 1% SP-2100 on 100/120
mesh Supelcoport, IX SP-1240 DA on 100/120 mesh Sepelcoport, 3% OV-17 on
100/120 mesh Gas Chron Q, 302 OV-17 on 100/120 mesh Gas Chrom o, and 1%
SP-1000 on Carbopak B.
VALIDATION STUDIES
The HDL for both compounds was determined by spiking them into reagent
water at a concentration two times the estimated detection limit of 1 ug/L
in weter. Seven replicate extractions at analyte concentration of 2 pg/L in
water were performed. The amount recovered was determined by external
standard calibration, and froa these data the MDL was calculated.
3

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An analytical curve was generated to determine the linearity of
recovery of the fumigants from reagent water. Reagent water was spiked in
duplicate to give analyte concentrations of 10, 50, 100, 500, and 1000 ug/L
in water. The water was extracted and plots were constructed of amount
recovered vs. amount spiked.
Recovery studies from two relevant wastewaters were also performed.
Two wastewaters were analyzed; one was a deep well injection brine from a
plant that manufactures ethylene dibromide, and the other was an untreated
effluent from a plant thct manufactures chloropicrin. The wastewaters were
extracted unspiked; seven replicate extractions were performed for each
wastewater. It was determined that the brine from the ethylene dibromide
manufacturing plant exhibited the higher background and was therefore
designated a high-level wastewater. The effluent from the chloropicrin
manufacturing plant was designated a low-level wastewater. None of the
extracts showed peaks at the retention times for chloropicrin or ethylene
dibromide.
Recovery studies were performed by spiking the low-level wastewater at
analyte concentrations of 5 ug/L and the high-level wastewater at analyte
concentrations of 50 ug/L. Seven replicate extractions were performed for
each spiked wastewater.
4

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SECTION 4
RESULTS AND DISCUSSION
EXTRACTION
The extraction solvent used in the method development and validation
U89 cyclohexane. Other solvents such as hexane, heptane, or isooctane can
also be used. However, many lots of solvents contain electron-capturing
interferences. For this reason, a solvent lot must be analyzed by GC-ECD
prior to use to determine its suitability for use with this method.
Recoveries of analytes spiked into reagent water are presented in Table
1. The recoveries were all very good except at the lower concentration
levels (one to two pg/L), and these recoveries were within the acceptable
range. The relative standard deviations were always less than 10 percent.
TABLE 1. RECOVERY OF FUMICANTS FROM WATER
Chloropicrin	Ethylene Dlbroa de
Spike Level* Average Recovery, Relative Standard Average Recovery, Relative Standard
liR/L
*(a>
Deviation, %
t(a)
DjviatIon
1000
109
4.7
97
3.7
100
98
0.6
96
1.6
40
95
3.1
100
2.8
20
90
2.3
95
3.2
10
90
2.6
300
4.7
4
85
3.5
100
5.7
2
80
5.1
95
4.8
1
78
7.7
84
10
(a) Average of triplicate analyses.
CHROMATOGRAPHY
Of the five columns evaluated, three (1% SP-2100, 1% SP-1240 DA and 32
OV-17) were unacceptable. The chloropicrin and ethylene dibrociide were not
well resolved from the solvent front and peak shapes were not acceptable.
The 302 OV-17 and 12 SP-1000 columns both gave good peak shapes and good
resolution even at low concentration levels. The 1% SP-1000 colunn is
already used for two US EPA Methods, 601 and 624. For these reasons, the 12
SP-1000 column was chosen as the primary column and used for method
validation. The 302 OV-17 column was chosen as the secondary column.
5

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The retention times for chloropicrin and ethylene dibromide on the
primary column (1% SP-1000 on Carbopak B) were 5.6 minutes and 9.9 minutes
respectively. The retention times on the secondary column (30% OV-17) were
2.25 minutes for chloropicrin and 3.3 minutes for ethylene dibromide.
Chromatograms of standard solutions of the two compounds on each column are
presented in Figures 1 and 2 respectively. The extraneous peaks present are
electron-capturing contaminants in the cyclohexane used to prepare the
standards.
The specific GC conditions used were:
Gas Chromatograph:
Detector:
Temperature Injector:
Detector Temperature:
Column Temperature:
Carrier Gas:
Varian Model 3700
Electron capture,
200°C
320°C
135°C (SP-1000), 80°C (OV-17);
isothermal
Nitrogen with flow rate of 30 mL/rain.
VALIDATION STUDIES
The MDLs for chloropicrin and ethylene dibromide were determined
to be 0.84 yg/'L and 0.20 yg/L respectively. For any further
validations based on the MDLs a "working" value of 1 ppb was used for
both compounds. Data from the MDL determination are presented in Table
2.
TABLE 2. DATA FROM MDL DETERMINATIONS
Conpound
Spike Level. Amount Recovered, Standard
	ug/L	r / L (a)	Deviation
MDL
Chloropicrin
Ethylene
Dibromide
2.00
2.CO
2.46
1.92
0.27
0.06
0.84
0.20
(a) Average of seven analyses.
The analytical curves	(amount	recovered vs. amount spiked) generated
are presented in Figures 3 and A.	The recoveries were close to linear over
the concentration range of	10-1000 Pg/L. Data used to generate these plots
are in Table 3.
6

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TABLE 3. DATA FROM GENERATION OF ANALYTICAL
CURVE
Amount Spiked,	Amount Recovered. ug/L(a)	
	Ug/L	Chloroplcrln	Ethylene Dlbromide
10	9.90	9.40
50	48.5	53.4
100	92.0	101
500	555	507
1000	975	985
(a) Average of duplicate analyses.
Chromatograas of extracts of the unspiked and spiked wastewaters are
presented in Figures 5, 6. The average percent recoveries and the relative
standard deviations for the spiked extractions are presented in Table 4.
Recoveries were acceptable for the high and low level spikes of chloropicrin
and for the high level spike of ethyene dibromide. The recovery of ethylene
dibromide at the low spike level five vg/L was below 85 percent. Since
recoveries of greater than 85 percent were achieved from distilled water at
concentrations lower than five pg/L, this poor recovery may be due to some
characteristic of the wastewater used for the low level spike study.
TABLE 4. RECOVERY OF CHLOROPICRIN AND ETHYLENE DIBRC-MIDE FROM WASTEWATERS
	Chloropicrin	 	Ethylene Dlbroalde	
Spike Level, Average Recovery, Relative Standard Average Recovery, Relative Standard
i^b/1	*(a)	Deviation. %	2(a)	Deviation, 'i
5	98	11.6	69	6.7
50	98.1	3.3	108	4.8
(a) Average of seven analyses.
7

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REFERENCES
1.	Moilanen, K.W., et al. Vapor-Phase Photodecomposition
of Chloropicrin (Trichloronitromethane). Tetrahedron,
34: 3345-3349, 1978.
2.	Lingg, R.D., et al. Quantitative Analysis of Volatile
Organic Compounds by GC-MS. Journal of American
Waterworks Assoc., 69 (11 part 1):605-612, 1977.
3.	Saito, N., Y. Ogino, and M. Nagoo. Analysis of Environmental
Chemical Substances. Okayama-ken Kankyo Hoken Senta Newpo,
3:173-174, 1979.
4.	Kroeller, K. Determination of Chloropicrin Residues in
Beverages. Deut. Lebensm.-Rumsch.t 67(5):150-152 1971.
5.	Heuser, S.G., and K. A. Scudmore. Determination of Ethylene
chlorohydren, Ethylene Dibromide and Other Volatile Fumigant
Residues in Fluor and Whole Wheat. Chem. Ind. (London),
37:1557-60, 1967.
6.	Going, J.E., and J.L. Spigarelli. Sampling and Analysis
of Selected Toxic Substances Task IV-Ethylene Dibromide.
EPA 560 16-76-021, U.S. Environmental Protection Agency,
Washington, D.C., 1976, 170 pp.
7.	Sidhu, J.S., M. Mutu , and G. S. Bains. A Study of 1,2-Dibromoethane
Residues in Wheat and Milled Products. Pestic. Sci., 6:451-455,
1975.
8.	Malone, B. Analysis of Grains for Multiple Residues of
Organic Fumigants Journal of the AOAC, 52(4):800-805,
1969.
9.	Thompson, R.H., et al. The Determination of Residues of
Volatile Fumigants in Grain. Analyst, 99:570-576, 1974.
10.	"The Analysis of Trihalomethanes in Drinking Water by Liquid-
Liquid Extraction - Method 501.2", U.S. Environmental
Protection Agency, Environmental Monitoring and Support
Laboratory, Cincinnati, Ohio, 45268, November 6, 1979.
8

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Retention Time, Min.
Figure 1. GC-ECD Chromatogram of 200 ng Chloropicrin and Ethylene Dibromide
(Column 1).

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Chloropicrin
Ethylene Dibromitle
0 1 2
Retention Time, Min.
Figure 2. GC-ECD Chronatogram of 400 ng Chloropicrin and Ethylene
Dibromide (Column 2).
10

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2B Oct 133
mi i-
62.1 j-
s&j t-
Amount Recovered^
Ug/L	:
2EI
/
ami ih aiFFiriEW. 195745
T MO:	C.483
SIM:
0.933
. I. ..1.. J. .. 1 u A 1 . J , I .
lfiB 2m m <&8 52.1 600.9 733.0
Amount Spiked, yg/L
I ^._l
a 8 lasa
Figure 3. Analytical Curve for Chloropicrin.
11

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29 Oct 19B3
Mi
Amount Recovered,
V g/L
L
V
/
me i-
2E0 -
i
i
mn *-
/
/

l&e za s me tag
CHaATIffl C3EFFICIEKT:
r KitECEPT:	1752
SLCPEi	8.586
. .1	I . . I .L 1 	I
I 728.2 6818 20.8 iblb
Amount Spiked, ug/L
Figure U. Analytical Curve for Ethylene Dibromide.
12

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Figure 5. GC-ECD Chromatogran of Cyclohexane Extract of Low
Level Wastewater (a) Unspiked and (b) Spiked With
.5 wg/L of Chloropicrin and Ethylene Dibromide.
13

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Figure 6. GC-ECD Chronatogram of Cyclohexane Extract of High
Level Wastewater (a) Unspiked and (b) Spiked Kith
50 yg/L of Chloropicrin and Ethylene Dibromide.
14

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METHOD 618 DETERMINATION OF VOLATILE PESTICIDES IN
MUNICIPAL AND INDUSTRIAL WASTEWATERS BY
GAS CHROMATOGRAPHY
1. Scope and Application
1.1	This method covers the determination of certain volatile pesti-
cides. The following parameters can be determined by this method:
Parameter	CAS No.
Chloropicrin	76-06-2
Ethylene dibromide	105-93-4
1.2	This is a gas chromatogrpahic (GC) method applicable to the
determination of the compounds listed above in municipal and
industrial discharges.
1.3	The method detection limit (HDL, defined in Section 15) for
each compound is listed in Table 1. The MDL for a specific
wastewater may differ from those listed, depending upon the
nature of interferences in the sample matrix.
1.4	This method is restricted to use by or under the supervision of
analysts experienced in the use of gas chromatography and in the
Interpretation of gas chromatograms. Each analyst must
demonstrate the ability to generate acceptable results with this
method using the procedure described in Section 8.2.
15

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1.5 When this method 1s used to analyze unfamiliar samples for any or
all of the compounds above, compound Identifications should be
supported by at least one additional qualitative technique. This
method describes analytical conditions for a second gas
chromatographic column that can be used to confirm measurements
made with the primary column. Section 14 provides gas
chromatograph/mass spectrometer (GC/MS) criteria appropriate for
the qualitative confirmation of compound identifications.
Summary of Method
2.1 A measured volume of sample, 20 mL, Is extracted with cyclohexane.
The cyclohexane extract 1s analyzed with no additional treatment.
Gas chromatographic conditions are described which permit the
separation of the compounds In the extract and their measurement
by an electron capture detector.
Interferences
3.1 Method interferences may be caused by contaminants 1n solvents,
reagents, glassware and other sample processing apparatus that
lead to discrete artifacts or elevated baselines in gas
chromatograms. All reagents and apparatus must be routinely
demonstrated to be free from interferences under the conditions of
the analysis by runr.lng laboratory reagent blanks as described in
Section 8.5.

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3.1.1	Glassware must be scrupulously cleaned.* Clean all
glassware as soon as possible after use hy thoroughly
rinsing with the last solvent used 1n 1t. Follow by
washing with hot water and detergent and thorough rinsing
with tap and reagent water. Drain dry, and heat In an
oven or muffle furnace at 400°C for 15 to 30 m1n. Do not
heat volumetric ware. Thorough rinsing with acetone may
be substituted for the heating. After drying and cooling,
seal and store glassware 1n a clean environment to prevent
any accumulation of dust or other contaminants. Store
inverted or capped with aluminum foil.
3.1.2	The use of high purity reagents and solvents helps to
minimize interference problems. Purification of solvents
by distillation in all-glass systems may be required.
3.2 Matrix interferences may be caused by contaminants that are
coextracted from the sample. The extent of matrix interferences
will vary considerably from source to source, depending upon the
nature and diversity of the Industrial complex or municipality
being sampled. Some samples may require a clean-up approach to
achieve the KDL listed in Table 1.
4. Safety
4.1 The toxicity or carcinogenicity of each reagent used in this
method has not been precisely defined; howeve", each chemical
compound should be treated as a potential health hazard.
17

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Chloropicrin produces severe sensory irritation in upper
respiratory passages. It has strong lacrimatory properties and
produces increased sensitivity after frequent exposures. Taken
orally, chloropicrin causes severe nausea, vomiting, colic, and
diarrhea. Chloropicrin is a potent skin irritant. Ethylene
dibromide liquid on the skin causes blisters if evaporation
is delayed. Inhalation of ethylene dibromide causes delayed
pulmonary lesions. Prolonged exposure may also result in liver
and kidney injury. Exposure to these chemicals must be reduced
to the lowest possible level by whatever means available. The
laboratory is responsible for maintaining a current awareness file
of OSHA regulations regarding the safe handling of the chemicals
specified in this method. A reference file of material data
handling sheets should also be made available to all personnel
involved in the chemical analysis. Additional references to
2-4
laboratory safety are available and have been identified for
the information of the analyst.
5. Apparatus and Materials
5.1 Sampling equipment, for discrete sampling.
5.1.1	Vial - 25-mL capacity or larger, equipped with a screw cap
with hole in center (Pierce No. 13075 or equivalent).
Detergent wash, rinse with tap and distilled water, and
dry at 105°C before use.
5.1.2	Septum - Teflon-faced silicone (Pierce No. 12722 or
18

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equivalent). Detergent wash, rinse with tap and distilled
water, and dry at 105°C before use.
5.2	Glassware (All specifications are suggested).
5.2.1	Centrifuge tube - 40 mL, with screw cap lined with Teflon.
5.2.2	Pipette - 4 mL graduated.
5.2.3	Graduated cylinder - 25 mL.
5.2.4	Volumetric flask -10 mL, ground glass stoppered.
5.3	Balance - Analytical, capable of accurately weighing to the
nearest 0.0001 g.
5.4	Gas chromatograph - Analytical system complete with gas
chromatograph suitable for on-column injection and all required
accessories including syringes, analytical columns, gases,
detector, and strip-chart recorder. A data system 1s recommended
for measuring peak areas.
5.4.1	Column 1 - 180 cm long x 2 mm ID glass, packed with 1%
SP-1000 on Carbopak B (60/80 mesh) or equivalent. This
column was used to develop the method performance
statements 1n Section 15. Alternative columns may be used
in accordance with the provisions described in Section
11.1.
5.4.2	Column 2 - 180 cm long x 2 mm ID glass, packed with 30%
0V-17 on Gas Chrom Q (100/120 mesh) or equivalent.
5.4.3	Detector - electron capture. This detector has proven
effective in the analysis of wastewaters for the compounds
listed in the scope and was used to develop the method
performance statements in Section 15. Alternative
detectors, including a mass spectrometer, may be used in
accordance with the provisions described in Section 12.1.
19

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Reagent water - Reagent water 1s defined as a water 1n which an
Interferent 1s not observed at the method detection limit of each
compound of Interest.
Cyclohexane - pesticide quality or equivalent. Because of the
frequent occurrence of electron-capturing contaminants 1n
solvents, several lots of solvent, or a different solvent^ e.g.
hexane, heptane, or isooctane, may have to be analyzed to find a
suitable extraction solvent.
Sodium hydroxide - 1n distilled water.
Sulfuric acid - 6f^ 1n distilled water.
Stock standard solutions (20 mg/ml) - Stock standard solutions can
be prepared from pure standard materials or purchased as certified
solutions. Prepare stock solutions in cyclohexane using assayed
liquids.
6.5.1 Place about 9.5 mL of pesticide-quality cyclohexane in a
10-mL volumetric flask. Allow the flask to stand,
unstoppered, for about 5 minutes or until all cyclohexane
wetted surfaces have dried. Weigh the flask to the
nearest 0.1 mg. Using a 250-uL syringe, immediately add
121 uL of chloropicrin (d^O = 1.66) and/or 92 ul of
ethylene dibromide (d^O = 2.18). The liquid must
fall directly into the cyclohexane without contacting the
neck of the flask. Reweigh, dilute to volume, stopper,
and mix by Inverting the flask several times. Calculate
the concentration 1n milligrams per milliliter (mg/mL)

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from the net gain 1n weight. Larger volumes can be used
at the convenience of the analyst. If compound purity 1s
certified at 96% or greater, the weight can be used
without correction to calculate the concentration of the
stock standard. Commercially prepared stock standards can
be used at any concentration 1f they are certified by the
manufacturer or by an Independent source.
6.5.2	Transfer the stock standard solutions Into Teflon-sealed
screw-cap bottles. Store at 4°C and protect from light.
Frequently check stock standard solutions for signs of
degradation or evaporation, especially just prior to
preparing calibration standards from them.
6.5.3	Stock standard solutions must be replaced after six
months or sooner if comparison with check standards
Indicates a problem.
7. Calibration
7.1	Establish gas chromatographic operating parameters equivalent to
those indicated in Table 1. The gas chromatographic system may be
calibrated using either the external standard technique (Section
7.2) or the Internal standard technique (Section 7.3).
7.2	External standard calibration procedure:
7.2.1 For each compound of interest, prepare calibration
standards at a minimum of three concentration levels by
adding accurately measured volumes of one or more stock
standards to a volumetric flask and diluting to volume
21

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with cyclohexane. One of the external standards should be
representative of a concentration near, but above, the
method detection Hm1t. The other concentrations should
correspond to the range of concentrations expected 1n the
sample concentrates or should define the working range of
the detector.
7.2.2	Using Injections of 1 to 5uL of each calibration
standard, tabulate peak height or area responses against
the mass injected. The results can be used to prepare a
calibration curve for each parameter. Alternatively, the
ratio of the response to the mass injected, defined as the
calibration factor (CF), can be calculated for each
compound at each standard concentration. If the relative
standard deviation of the calibration factor 1s less
than 10% over the working range, the average calibration
factor can be used 1n place of a calibration curve.
7.2.3	The working calibration curve or calibration factor must
be verified on each working shift by the measurement of
one or more calibration standards. If the response for
any compound varies from the predicted response by more
than +_ 10%, the test must be repeated using a fresh
calibration standard. Alternatively, a new calibration
curve or calibration factor must be prepared for that
parameter.
22

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7.3 Internal standard calibration procedure. To use this approach,
the analyst must select one or more Internal standards similar In
analytical behavior to the compounds of Interest. The analyst
must further demonstrate that the measurement of the Internal
standard 1s not affected by method or matrix interferences. Due
to these limitations, no internal standard applicable to all
samples can be specified; however, bromoform has been shown to be
satisfactory 1n some cases.
7.3.1	Prepare calibration standards at a minimum of three
concentration levels for each compound of interest by
adding volumes of one or more stock standards to a
volumetric flask. To each calibration standard, add a
known constant amount of one or more internal standards,
and dilute to volume with cyclohexane. Orie of the
standards should be representative of a concentration
near, but above, the method detection limit. The other
concentrations should correspond to the range of
concentrations expected in the sample concentrates or
should define the working range of the detector.
7.3.2	Using injections of 1 to 5 uL of each calibration
standard, tabulate the peak height or area responses
against the concentration for each compound and internal
standard. Calculate response factors (RF) for each
compound as follows:
23

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RF » (AsC-js)/(A-|sCs)
where:
As ¦ Response for the compound to be measured.
Ajs » Response for the Internal standard.
Cjs * Concentration of the Internal standard 1n ug/L.
Cs ¦ Concentration of the compound to be measured in
ug/L.
If the RF value over the working range Is constant, less
than 10% relative standard deviation, the RF can be
assumed to be Invariant and the average RF can be used for
calculations. Alternatively, the results can be used to
plot a calibration curve of response ratios, As/Ajs
against RF.
7.3.3 The working calibration curve or RF must be verified on
each working shift by the measurement of one or more
calibration standards. If the response for any compound
varies from the predicted response by more than _+ 10%,
the test must be repeated using a fresh calibration
standard. Alternatively, a new calibration curve must be
preparedfor that compound.
Before using any cleanup procedure, the analyst must process a
series of calibration standards through the procedure to validate
elution patterns and the absence of interferences from the
reagents.
2U

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8. Quality Control
8.1	Each laboratory using this method 1s required to operate a formal
quality control program. The minimum requirements of this program
consist of an Initial demonstration of laboratory capability and
the analysis of spiked samples as a continuing check on perfor-
mance. The laboratory 1s required to maintain performance
records to define the quality of data that 1s generated.
8.1.1	Before performing any analyses, the analyst must
demonstrate the ability to generate acceptable accuracy
and precision with this method. This ability Is
established as described 1n section 8.2.
8.1.2	In recognition of the rapid advances occurring 1n chroma-
tography, the analyst 1s permitted certain options to
improve the separations or lower the cost of measurements.
Each tiire such modifications to the method are made, the
analyst is required to repeat the procedure In Section
8.2.
8.1.3	The laboratory must spike and analyze a minimum of 10% of
all samples to monitor continuing laboratory performance.
This procedure is described 1n Section 8.4.
8.2	To establish the ability to generate acceptable accuracy and
precision, the analyst must perform the following operations.
8.2.1 Select a representative spike concentration for each
compound to be measured. Using stock standards, prepare a
25

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quality control check sample concentrate 1n methanol such
that a 4-uL aliquot of the check sample concentrate 1n
20-mL of water gives the selected concentration.
8.2.2	Using a 10-uL syringe add 4 uL of the check sample
concentrate to each of a minimum of four 20-mL allquots of
reagent water. A representative wastewater may be used 1n
place of the reagent water, but one or more additional
allquots must be analyzed to determine background levels,
and the spike level must exceed twice the background level
for the test to be valid. Analyze the allquots according
to the method beginning 1n Section 10.
8.2.3	Calculate the average percent recovery (R), and the
standard deviation of the percent recovery (s), for the
results. Wastewater background corrections must be made
before R and s calculations are performed.
8.2.4	Using the appropriate data from Table 2, determine the
recovery and single operator precision expected for the
method, and compare these results to the values measured
1n Section 8.2.3. If the data are not comparable,
review potential problem areas and repeat the test.
8.3 The analyst must calculate method performance criteria and define
the performance of the laboratory for each spike concentration and
compound being measured.
26

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8.3.1 Calculate upper and lower control limits for method
performance as follows:
Upper Control Limit (UCL) ¦ R + 3 s
Lower Control Limit (LCL) ¦ R - 3 s
where R and s are calculated as 1n Section 8.2.3. The UCL
and LCL can be used to construct control charts^ that
are useful 1n observing trends In performance.
8.3.2 The laboratory must develop and maintain separate accuracy
statements of laboratory performance for wastewater
samples. An accuracy statement for the method 1s defined
as R + s. The accuracy statement should be developed by
the analysis of four allquots of wastewater as described
1n Section 8.2.2, followed by the calculation of R and s.
Alternately, the analyst may use four wastewater data
points gathered through the requirement for continuing
quality control 1n Section 8.4. The accuracy statements
should be updated regularly.5
8.4 The laboratory 1s required to collect in duplicate a portion of
their samples to monitor spike recoveries. The frequency of
spiked sample analysis must be at least 101 of all samples or one
sample per month, whichever is greater. One aliquot of the sample
must be spiked and analyzed as described 1n Section 8.2. If the
recovery for a particular compound does not fall within the
control limits for method performance, the results reported for
that compound in all samples processed as part of the same set
27

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must be qualified as described In Section 13.3. The laboratory
should monitor the frequency of data so qualified to ensure that
1t remains at or below 5%.
8.5	Before processing any samples, the analyst should demonstrate
through the analysis of a 20-mL aliquot of reagent water that all
glassware and reagents Interferences are under control. Each time
a set of samples 1s extracted or there 1s a change 1n reagents, a
laboratory reagent blank should be processed as a safeguard
against laboratory contamination.
8.6	It Is recommended that the laboratory adopt additional quality
assurance practices for use with this method. The specific
practices that are most productive depend upon the needs of the
laboratory and the nature of the samples. Field duplicates may be
analyzed to monitor the precision of the sampling technique. When
doubt exists over the Identification of a peak on the chromato-
gram, confirmatory techniques such as gas chromatography with a
dissimilar column, specific element detector, or mass spectro-
meter must be used. Whenever possible, the laboratory should
perform analysis of quality control materials and participate in
relevant performance evaluation studies.
9. Sample Collection, Preservation, and Handling
9.1 Grab samples must be collected in glass containers having a total
volume of at least 25 mL. Fill the sample bottle just to
overflowing in such a manner that no air bubbles pass through the
28

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sample as the bottle Is being filled. Seal the bottle so that no
air bubbles are entrapped 1n it. Store the sample 1n an Inverted
position and maintain the hermetic seal on the sample bottle until
the time of analysis.
9.2 The samples must be Iced or refrigerated at 4°C from the time of
collection until extraction.
10.	Sample Extraction
10.1	Measure 20 mL of sample by pouring the sample Into a 40-mL
centrifuge tube equipped with a Teflon-Hned screw cap to a
predetermined 20-mL mark. Adjust pH of sample to 6-8 by addition
of 6_N sodium hydroxide or 6^ sulfuric acid. Measure 4.0 mL of
extraction solvent with a 4-mL graduated pipette and add to the
centrifuge tube.
10.2	Shake the tube vigorously for one minute. Allow the layers to
separate for at least 10 minutes. Centrifuge, if necessary, to
facilitate phase separation.
10.3	Withdraw an aliquot of the solvent layer and proceed with gas
chromatographic analysis.
11.	Cleanup and Separation
11.1 Cleanup procedures are not generally necessary. . If particular
circumstances demand the use of a cleanup procedure, the analyst
must determine the elutlon profile and demonstrate that the
recovery of each compound of interest is no less than 85X.
29

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12. Gas Chromatography
12.1	Table 1 summarizes the recommended operating conditions for the
gas chromatograph. Included 1n this table are estimated retention
times and method detection limits that can be achieved by this
method. Examples of the separations achieved by Columns 1 and 2
are shown 1n Figures 1 and 2, respectively. Other packed columns,
chromatographic conditions, or detectors may be used 1f the
requirements of Section 8.2 are met. Capillary (open-tubular)
columns may also be used If the relative standard deviations of
responses for replicate injections are demonstrated to be less
than 6% and the requirements of Section 8.2 are met.
12.2	Calibrate the system daily as described in Section 7.
12.3	If the internal standard approach is being used, the analyst must
not add the internal standard to sample extracts until immediately
before injection into the instrument. Mix thoroughly.
12.4	Inject 1 to 5 uL of the sample extract using the sol vent-flush
technique.® Record the volume injected to the nearest 0.05 uL,
and the resulting peak size In area or peak height units. An
automated system that consistently injects a constant volume of
extract may also be used.
12.5	The width of the retention time window used to make Identifica-
tions should be based upon measurements of actual retention time
variations of standards over the course of a day. Three times the
30

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standard deviation of a retention time can be used to
calculate a suggested window size for a compound. However,
the experience of the analyst should weigh heavily 1n the
Interpretation of chromatograms.
12.6	If the response for the peak exceeds the working range of the
system, dilute the extract and reanalyze.
12.7	If the measurement of the peak response 1s prevented by the
presence of Interferences, further cleanup 1s required.
13. Calculations
13.1 Determine the concentration of Individual compound'. 1n the sample.
13.1.1	If the external standard calibration procedure 1s used,
calculate the amount of material injected from the peak
response using the calibration curve or calibration factor
1n Section 7.2.2. The concentration In the sample can be
calculated as follows:
(A)(Vt)
Concentration, ug/L =
(*i)>
where:
A = Amount of material Injected, 1n nanograms.
V'i = Volume of extract Injected in uL.
Vt = Volume of total extract in uL.
Vs = Volume of water extracted in mL.
13.1.2	If the internal standard calibration procedure is used,
calculate the concentration 1n the sample using the
31

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response factor (RF) determined 1n Section 7.3.2 as
follows:
(AS)(IS)
Concentration, ug/l » 	
(Ais)(RF)(V0)
where:
As ¦ Response for the parameter to be measured.
Ajs ¦ Response for the Internal standard.
Is » Amount of Internal standard added to each extract
in ug.
V0 = Volume of water extracted, 1n liters.
13.2	Report results in micrograms per liter without correction for
recovery data. When duplicate and spiked samples are analyzed,
report all data obtained with the sample results.
13.3	For samples processed as part of a set where the laboratory spiked
sample recovery falls outside of the control limits in Section
8.3, data for the affected compounds must be labeled as suspect.
GC/MS Confirmation
14.1 It is recommended that GC/MS te-chniques be judiciously employed to
support qualitative Identifications made with this method. The
mass spectrometer should be capable of scanning the mass range
from 35 amu to a mass 50 amu above the molecular weight of the
compound. The instrument must be capable of scanning the mass
range at a rate to produce at least 5 scans per peak but not to
32

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exceed 7 seconds per scan utilizing a 70 V (nominal) electron
energy in the electron Impact Ionization mode. A GC to MS
interface constructed of all-glass or glass-Hned materials 1s
recommended. A cortputer system should be Interfaced to the mass
spectrometer that allows the continuous acquisition and storage on
machine readable media of all mass spectra obtained throughout the
duration of the chromatographic program.
14.2	Gas chromatographic columns and conditions should be selected for
optimum separation and performance. The conditions selected must
be compatible with standard GC/MS operating practices. Chromato-
graphic tailing factors of less than 5.0 must be achieved.9
14.3	At the beginning of each day that confirmatory analyses are to be
performed, the GC/MS system must be checked to see that all
decafluorotriphenyl phosphine (DFTPP) performance criteria are
achieved.^
14.4	To confirm an identification of a compound, the background
corrected mass spectrum of the compound mist be obtained from the
sample extract and compared with a mass spectrum from a stock or
calibration standard analyzed under the same chromatographic
conditions. It is recommended that at least 25 nanograms of
material be injected into the GC/MS. The criteria below must be
met for qualitative confirmation.
33

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14.4.1	Al*. 1ons that are present above 10% relative abundance 1n
the mass spectrum of the standard must be present 1n the
mass spectrum of the sample with agreement to plus or
minus 10%. For example, If the relative abundance of an
1on 1s 30% 1n the mass spectrum of the standard, the
allowable limits for the relative abundance of that 1on 1n
the mass spectrum for the sample would be 20 to 40%.
14.4.2	The retention time of the compound 1n the sample must be
within 6 seconds of the same compound In the standard
solution.
14.4.3	Compounds that have very similar mass spectra can be
explicitly identified by GC/MS only on the basis of
retention time data.
14.5	Where available, chemical ionization mass spectra may be employed
to aid 1n the qualitative Identification process.
14.6	Should these MS procedures fail to provide satisfactory results,
additional steps may be taken before reanalysis. These may
Include the use of alternate packed or capillary GC columns or
additional cleanup (Section 11).
15. Method Performance
15.1 The method detection limit (MDL) is defined as the minimum
concentration of a substance that can be measured and reported
34

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with 99? confidence that the value 1s above zero.I® The MDL
concentrations listed 1n Table 1 were obtained using reagent
water.® Similar results were achieved using representative
wastewaters.
15.2	This method has been tested for linearity of recovery from spiked
reagent water and has been demonstrated to be applicable over the
concentration range from 10 x MDL to 1000 x HDL.
15.3	In a single laboratory, Battelle Columbus Laboratories, using
spiked wastewater samples, the average recoveries presented In"
Table 2 were obtained. Seven replicates each of two different
wastewaters were spiked and analyzed. The relative standard
deviations of the percent recovery of these measurements are also
Included 1n Table 2.
35

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REFERENCES
1.	ASTM Annual Book of Standards, Part 31, D3694, "Standard Practice for
Preparation of Sample Containers and for Preservation," American Society
for Testing and Materials, Philadelphia, PA, p. 679, 1980.
2.	"Carcinogens - Working with Carcinogens," Department of Health,
Education, and Welfare, Public Health Service, Center for Disease
Control, National Institute for Occupational Safety and Health,
Publication No. 77-206, Aug. 1977.
3.	"OSHA Safety and Health Standards, General Industry," (29 CFR 1910),
Occupational Safety and Health Administration, OSKA 2206 (Revised,
January 1976).
4.	"Safety 1n Academic Chenlstry Laboratories," American Chemical Society
Publication, Committee on Chemical Safety, 3rd Edition, 1979.
5.	"Handbook for Analytical Quality Control In Water and Wastewater
Laboratories," EPA-600/4-79-019, U.S. Environmental Protection Agency,
Environmental Monitoring and Support Laboratory - Cincinnati, Ohio 45268,
March 1979.
6.	Burke, J. A., "Gas Chromatography for Pesticide Residue Analysis; Some
Practical Aspects," Journal of the Association of Official Analytical
Chemists, 48, 1037 (1965).
7.	Elchelberger, J. W., Harris, L. E., and Budde, W. L., "Reference Compound
to Calibrate Ion Abundance Measurement 1n Gas Chromatography--Mass
Spectrometry", Analytical Chemistry, 47, 995 (1975).
8.	"Development of Methods for Pesticides in Wastewaters," Report from
Battelle's Columbus Laboratories for EPA Contract 68-03-2956 (in
preparation).
9.	McNair, H. M. and Bonelll, E. J., "Basic Chromatography", Consolidated
Printing, Berkeley, California, 52 (1969).
10. Glaser, J. A. et al., "Trace Analysis for Wastewaters", Enviromiental
Science and Technology, 15, 1426 (1981).
36

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TABLE 1. CHROMATOGRAPHIC CONDITIONS AND ESTIMATED
METHOD DETECTION LIMITS
Parameter
Retention Time (mln.)
Column 1 Column 2
MDL
(f9/L)
Chloroplcrln
5.60
2.03
0.8
Ethylene Dibromide
9.90
3.15
0.2
Column 1 conditions:
Carbopak B (60/80 mesh) coated with 1%
SP-1000 packed in a 1.8 m long x 2 mm ID
glass column with nitrogen carrier gas at a
flow rate of 30 mL/min. Column temperature,
isothermal at 135°C. An electron capture
detector was used with this column to determine
the MDL.
Column 2 conditions:
Gas Chrom Q (100/120 mesh) coated with 30S 0V-17
packed in a 1.8 m Jong by 2 mm ID glass column with
helium carrier gas at a flow rate of 25 mL/min.
Column temperature, isothermal at 95°C.
37

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TABLE 2. SINGLE LABORATORY ACCURACY AND PRECISION*4)
Spike Mean Standard	Number
Sample Background Level Recovery Deviation	of
Parameter Type'*5) ug/Llc) ug/L (I)	(X)	Replicates
Chloropicrln 1	KD	5	?8	12	7
2	ND	50	98	3.3	7
Ethylene 1	NO	5	69	6.9	7
Dlbromide 2	ND	50	108	4.8	7
(a)	Column 1 conditions were used.
(b)	1 = Low background relevant industrial effluent.
2 = High background relevant Industrial effluent.
(c)	ND = Not detected.
38

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FIGURE 1. GC-ECD CHROMATOGRAM OF 200 ng CHLOROPICRIN AND ETHYLENE OIBROMIDE IN
CYCLOHEXANE (COLUMN 1)

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Chloropicrin
Retention Time, Min.
FIGURE 2. GC-ECD CHROMATOGRAM OF 400 ng CHLOROPICRIN AND ETHYLENE
DIBROMIDE IN CYCLOHEXANE (COLUMN 2).
40

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