United States
Environmental Protection
Agency
Atmospheric Research and
Exposure Assessment Laboratory
Research Triangle Park, NC 27711
Research and Development
EPA/600/SR-93/101 September 1993
vyEPA Project Summary
Field Test of Generic Method for
Halogenated Hydrocarbons
J.F. McGaughey, J.T. Bursey, R.G. Merrill, Jr.
Validation of a method for a particu-
lar analyte or group of analytes means
that the performance of the sampling
and analytical methodology for these
analytes has been established and dem-
onstrated through field tests at the type
of source category of interest: that is,
the precision and bias of the method
have been established experimentally.
In examination of the available method
validation data for organic compounds
listed in Title III of the Clean Air Act
Amendments (CAAA) of 1990, the lack
of overall method validation data is
readily apparent. In some cases, ana-
lytical methods have been validated for
a number of analytes, but there is no
validation information for the sampling
methodology. Full validation for sam-
pling and analytical methods, for both
field and laboratory operations, is avail-
able for fewer than 10 % of the analytes
listed in Title III of the CAAA at any
source category. Field validation may
be performed by side-by-side compari-
son of a candidate method to a vali-
dated method to establish comparable
performance for the same analytes in
the same matrix (same source cat-
egory). Another procedure for valida-
tion of a method is to perform spiking
operations in the field so that the pre-
cision and bias of the method can be
demonstrated from sample collection
through analysis. Both dynamic and
static procedures for the validation of
a method are permitted in EPA's Vali-
dation Protocol in Method 301.
This Project Summary was developed
by EPA's Atmospheric Research and
Exposure Assessment Laboratory, Re-
search Triangle Park, NC, to announce
key findings of the research project
that is fully documented in a separate
report of the same title (see Project
Report ordering information at back).
Introduction
The United States Environmental Pro-
tection Agency (EPA), under the authority
of Title III of the Clean Air Act Amend-
ments (CAAA) of 1990, requires the iden-
tification and/or validation of sampling and
analytical methods for the halogenated
volatile and semivolatile organic com-
pounds which are listed (Table 1 and Table
2). The candidate methods for testing the
volatile organic compounds are VOST
(SW-846 Sampling Method 0030 and SW-
846 Analytical Methods 5040 or 5041),
and for testing the semivolatile organic
compounds, SemiVOST (SW-846 Sam-
pling Method 0010 and SW-846 Analytical
Method 8270) is used. The VOST and
SemiVOST methods were first evaluated
in a laboratory environment, and dynamic
spiking procedures were also developed
and evaluated. The results of the labora-
tory study were reported in an earlier docu-
ment.
After the laboratory evaluation, the next
step was to attempt to validate the two
candidate test methods at a coal-fired
power plant that does not routinely emit
high levels of these hazardous air pollut-
ants (HAPs). The absence of high levels
of the HAPs was determined by analyzing
samples collected during a pretest sur-
vey. A field test was planned to further
verify the analyte spiking methodology in
a non-laboratory environment and to as-
sess the added effect of sampling a com-
1^ A) Printed on Recycled Paoer
-------
bustion matrix (stack gas). Minimizing the
source contribution of the HAPs in the
sample matrix simplified the evaluation of
the results for the effectiveness of the
spiking procedures. A source with signifi-
cant levels of all the HAPs shown in Tables
1 and 2 could not be located.
Results and Discussion
Validation of VOST and SemiVOST was
accomplished by performing sampling and
analysis following the EPA methods ex-
cept for the use of a quadruple (QUAD)
probe system required by EPA Method
301. Validation procedures for a method
include protocols for determining and docu-
menting the quality of data generated by
that method. The bias (systematic error)
and precision (reproducibility of measure-
ment) are determined in a statistically valid
manner. The procedures for validating a
method for a given analyte or set of
analytes require introducing known con-
centrations of the analyte(s) into the sam-
pling train or comparing the candidate
method against a validated test method.
The bias of the method can be evaluated
by determining the recovery of the known
quantity of analyte which has been spiked
into the sampling train or by comparison
of the results obtained by the candidate
method to the results obtained by the vali-
dated method. In order to determine the
precision of the test method, multiple or
collocated simultaneous samples are taken
and analyzed. If dynamic spiking tech-
niques are used, it is essential that the
analyte be introduced into the sampling
train as near to the end of the probe as
possible, and that the analyte be intro-
duced continuously for the duration of the
sampling operation.
Bias may result from analytical interfer-
ences, errors in calibration, or inefficien-
cies in the collection of the analyte. When
the bias of the method is determined for a
given analyte, a correction for the bias
may be made. The EPA Method 301 al-
lows for this correction within a range of
70 to 130%. Bias values outside this range
may require the rejection of the candidate
method.
Precision is the variability in the data
that is obtained from the entire measure-
ment system (both sampling and analysis)
as determined from the multiple or collo-
cated sampling trains. Following the EPA
Method 301 procedures, two paired sam-
pling trains were used to determine the
precision of the entire system. Use of
QUAD trains with four collocated sam-
pling probes allows operation of two spiked
trains and two unspiked trains. EPA
Method 301 requires that the precision
not be greater than 50 % relative stan-
dard deviation for the method to be valid.
To determine bias and precision in the
field, a total of 24 samples using qua-
druple collocated sampling trains was col-
lected. For quadruple trains, six complete
sampling runs constitute the minimum
Method 301 requirement.
The halogenated compounds listed in
the CAAA of 1990 for which method vali-
dation is required and for which labora-
tory testing has been performed are shown
in Tables 1 and 2. Pesticides, polychlori-
nated biphenyls, 2,3,7,8-tetrachlorodi-
benzo-p-dioxin, and dibenzofurans were
excluded from this study, since special-
ized methods are available for these
analytes Not all of the candidate analytes
for the VOST and SemiVOST performed
successfully in those methods. Four com-
pounds could not be analyzed by the
VOST of SemiVOST methods either in
the laboratory or in the field:
• Bis(chloromethyl) ether, chloromethyl
methyl ether, and epichlorohydrin
could not be analyzed by the VOST
analytical method. Since these com-
pounds are water-soluble and react
with water, the failure of the VOST
analytical methodology was antici-
pated.
• Chloroacetic acid could not be ana-
lyzed in the SemiVOST analytical
method because of its unstable and
reactive nature.
The laboratory evaluation included the
following components:
• Determination of chromatographic re-
tention times for both volatile and
semivolatile compounds using gas
chromatography/mass spectrometry
(GC/MS);
• Determination of recoveries from sor-
bents for both volatile and semivolatile
compounds;
• Determination of analytical method de-
tection limits for both volatile and
semivolatile halogenated organic com-
pounds; and
• Design, construction, and evaluation
of dynamic spiking equipment and
techniques for use in the field spiking
of volatile and semivolatile haloge-
nated organic compounds.
The fied validation of the VOST and
SemiVOST was accomplished by dynami-
cally spiking the trains with the specific
halogenated organic compounds while si-
multaneously sampling emissions from a
combustion source. During each QUAD
sampling run, only two of the four sam-
pling trains were dynamically spiked; the
other two unspiked trains were used to
establish the background level of any tar-
get compounds in the stack gas. A sam-
pling scheme to meet the requirements of
method validation was designed statisti-
cally to ensure the collection of appropri-
ate numbers of samples for each method.
Samples were analyzed according to SW-
846 Method 5041 and SW-846 Meth-
od 8270, with statistical evaluation of data.
Results are summarized in Tables 3 and
4.
Based on the work performed in the
laboratory and the field evaluation of the
VOST and SemiVOST methods, the fol-
lowing conclusions may be drawn from
the results shown in Tables 3 and 4:
• Using the criteria for acceptable per-
formance of recovery between 50 and
150 %, with a percent standard de-
viation of 50 or less, the VOST meth-
odology performed successfully in a
coal-fired boiler emission matrix at a
nominal concentration of 12 ng/liter
for the following compounds: cis-1,3-
dichloropropene, trans-1,3-dichloro-
propene, trichloroethene, methyl chlo-
roform (1,1,1-trichloroethane), carbon
tetrachloride, vinyl chloride, 1,1,2-tri-
chloroethane, tetrachloroethene, chlo-
robenzene, vinylidene chloride (1,1-
dichloroethene), chloroform, methyl-
ene chloride, ethylene dichloride (1,2-
dichloroethane), ethylidene dichloride
(1,1-dichloroethane), methyl iodide
(iodomethane), propylene dichloride
(1,2-dichloropropane), vinyl bromide,
methyl bromide (bromomethane), and
ethyl chloride (chloroethane).
• Using the criteria for acceptable per-
formance of recovery between 50 and
150 % with a percent relative stan-
dard deviation of 50 or less, the
SemiVOST methodology performed
successfully in a coal-fired boiler emis-
sions matrix at a nominal concentra-
tion of 6 |ig/ft3 for the following com-
pounds: hexachloroethane, benzyl
chloride, hexachlorobutadiene, 1,1,2-
trichloroethane, 2,4,5-trichlorophenol,
chlorobenzene, dichloroethyl ether,
benzotrichloride, bromoform, 1,2,4-tri-
chlorobenzene, ethylene dibromide
(1,2-dibromoethane), 1,1,2,2-tetra-
chloroethane, 1,4-dichlorobenzene, 2-
chloroacetophenone, tetrachloro-
ethene, and trans-1,3-dichloro-
propene.
-------
The VOST methodology did not per-
form acceptably .under the field con-
ditions for methyl chloride (chloro-
methane), chloroprene, ethylene di-
bromide (1,2-dibromoethane), and al-
lyl chloride (3-chloropropene).
The SemiVOST methodology did not
perform acceptably under the field
conditions for 2,4,6-trichlorophenol,
cis-1,3-dichloropropene, 1,2-dibromo-
3-chloropropane, hexachlorobenzene,
pentachloronitrobenzene, pentachlo-
rophenol, hexachlorocyclopentadiene,
chlorobenzilate, epichlorohydrin, 3,3'-
dichlorobenzidine, and bis(chloro-
methyl) ether.
Some compounds were tested in both
methodologies because they exhib-
ited volatility (boiling points) appropri-
ate for inclusion in either method. The
following compounds performed ac-
ceptably in both VOST and Semi-
VOST: tetrachloroethene, trans-1,3-
dichloropropene, 1,1,2-trichloroethane,
and chlorobenzene. Ethylene dibro-
mide (1,2-dibromoethane) performed
acceptably in the SemiVOST meth-
odology, but did not meet recovery
criteria for the VOST methodology.
cis-1,3-Dichloropropene performed ac-
ceptably using the VOST methodol-
ogy but did not meet the criteria for
successful performance in the
SemiVOST methodology.
Table 1. Halogenated Compounds for Which Laboratory Testing Has Determined the Applicability of the VOST Method.
Compound
Boiling point fC)
Comments
Allyl chloride
bis(chloromethyl) ether
Carbon tetrachloride
Chlorobenzene
Chloroform
Chloromethyl methyl ether
Chloroprene
1 , 3-Dichloropropylene
Epichlorohydrin
Ethyl chloride
Ethylene dibromide
Ethylene dichloride
Ethylidene dichloride
Methyl bromide
Methyl chloride
Methyl chloroform
Methylene chloride
Methyl iodide
Propylene dichloride
Tetrachloroethylene
1, 1,2-Trichloroethane
Trichloroethylene
Vinyl chloride
Vinyl bromide
Vinylidene chloride
44-46
106 '
77
132'
60.5-61.5
55-57
59.4
1 05-106 2
115-177'
123
131-132 '
83
57
43
-24.2 3
74-76
39.8-40
41-43
95-96
121 '
110-115'
86.9
-13.43
164
30-32
Acceptable performance in laboratory
Decomposes in water; cannot be analyzed
Recovery too high in laboratory study
Acceptable performance in laboratory
Acceptable performance in laboratory
Decomposes in water; cannot be analyzed
Acceptable performance in laboratory
Acceptable performance in laboratory
Decomposes in water; cannot be analyzed
Acceptable performance in laboratory
Acceptable performance in laboratory
Acceptable performance in laboratory
Acceptable performance in laboratory
Recovery unacceptable high in laboratory
Erratic and unacceptable n laboratory
Recovery too high in laboratory study
Recovery too high in laboratory study
Acceptable performance in laboratory
Acceptable performance in laboratory
Acceptable performance in laboratory
Acceptable performance in laboratory
Acceptable performance in laboratory
Acceptable performance in laboratory
Acceptable performance in laboratory
Acceptable performance in laboratory
Above the maximum VOST boiling point of 100°C; Included in the testing because compounds in the range of 100-132°C are frequently tested by the VOST method.
Boiling temperature at 730 mm Hg.
Below the common lower temperature limit of 30°C usually used for VOST.
Boiling temperature at 750 mm Hg.
Table 2. Halogenated Compounds for which Laboratory Testing has Determined the Applicability of the SemiVOST Method.
Compound
Boiling po
Comments
Benzotrichloride
Benzyl chloride
bis(Chloromethyl) ether4
Bromoform
Chloroacetic acid
Chlorobenzene4
2-Chloroacetophenone
Chlorobenzilate
1,2-Dibromo-3-chloropropane
219-223
177-181
106
150-151
189
132
244-245
147
196
Acceptable performance in laboratory
Acceptable performance in laboratory
Unacceptably low recovery in laboratory
Acceptable performance in laboratory
Cannot be analyzed by SemiVOST method
Acceptable performance in laboratory
Acceptable performance in laboratory
Unacceptably low recovery in laboratory
Acceptable performance in laboratory
-------
Table 2. Halogenated Compounds for which Laboratory Testing has Determined the Applicability of the SemiVOST Method (continued).
Compound
Boiling point (°C)
Also tested in VOST methodology.
Boiling temperature at 740 mm Hg.
Boiling temperature at 730 mm Hg.
Boiling temperature at 15 mm Hg.
Table 3. Results of VOST Field Validation
Comments
1 ,4-Dichlorobenzene
3,3'-Dichlorobenzidine
Dichloroethyl ether
1 , 3-Dichloropropene
Epichlorohydrin '
Ethylene dibromide '
Hexachlorobenzene
Hexachlorobutadiene
Hexachlorocyclopentadiene
Hexachloroethane
Pentachloronitrobenzene
Pentachlorophenol
1, 1,2,2-Tetrachloroethane
Tetrachloroethylene '
7, 2, 4- Trichlorobenzene
1,1,2-Trichloroethane '
2,4, 5- Trichlorophenol
2, 4, 6- Trichlorophenol
173
MP=165
6567"
105 106 3
115-117
131-132
323-326
210-220
239
186
328
3095
147
121
214
110-115
248 2
246
Acceptable performance in laboratory
Erratic performance in laboratory
Acceptable performance in laboratory
Unacceptably low recovery in laboratory
Acceptable performance in laboratory
Acceptable performance in laboratory
Unacceptably low recovery in laboratory
Acceptable performance in laboratory
Erratic performance in laboratory
Acceptable performance in laboratory
Unacceptably low recovery in laboratory
Unacceptably low recovery in laboratory
Acceptable performance in laboratory
Unacceptably low recovery in laboratory
Acceptable performance in laboratory
Acceptable performance in laboratory
Erratic performance in laboratory
Unacceptably low recovery in laboratory
Compound
Percent recovery
Percent RSD
Methyl chloride (chloromethane)
Ethylidene dichloride (1, 1 -dichloroethane)
Chlorobenzene
Vinyl chloride
Vinylidene chloride (1, 1-dichloroethylene)
Chloroform
Propylene dichloride (1,2-dichloropropane)
Methyl bromide (bromomethane)
Ethyl chloride (chloroethane)
Methylene chloride
Methyl chloroform (1, 1, 1-trichloroethane)
Carbon tetrachloride
Ethylene dichloride (1,2-dichloroethane)
Trichloroethylene
cis- 1, 3-Dichloropropene
trans - 1 , 3-Dichloropropene
1, 1,2-Trichloroethane
Tetrachloroethene
Methyl iodide (iodomethane)
Allyl chloride (3-chloropropene)
Ethylene dichloride (1,2-dibromoethane)
Chloroprene
Vinyl bromide
937.0
75.7
88.2
110.4
88.0
81.8
67.2
53.7
50.3
77.7
109.6
106.7
76.6
125.5
136.8
134.9
98.0
97.7
72.8
29.9
34.9
40.1
60.7
53.8
13.7*
22. 02
27.32
31.32
14.82
9.6?
20.22
28. T2
27.1*
43. S2
47.2s
33.02
15.62
26. 02
38. 12
22. 12
21.92
37.6
19.5
31.6
22.4
34.32
1 Chloromethyl methyl ether, bis(chloromethyl) ether, and epichlorohydrin could not be analyzed by the VOST methodology.
2 Acceptable performance by the analyte in the VOST method, using acceptability criteria of 50-150% recovery, with Percent Relative Standard Deviation of 50 or less.
-------
Table 4. Results of SemiVOST Field Validation
Compound Percent recovery Percent RSD
bis(Chloromethyl) ether
Epichlorohydrin
cis- 1, 3-Dichloropropene
trans- 1 , 3-Dichloropropene
1, 1,2-Trichloroethane
1 ,2-Dibromoethane
Tetrachloroethene
Chlorobenzene
Bromoform
1, 1,2,2-Tetrachloroethane
Dichloroethyl ether
1 ,4-dichlorobenzene
Benzyl chloride
Hexachloroethane
1 , 2-Dibromo-3-chloropropane
1,2,4- Trichlorobenzene
Hexachlorobutadiene
Benzotrichloride
2- Chloroace tophenone
Hexachlorocyclopentadiene
2,4, 6- Trichlorophenol
2,4, 5- Trichlorophenol
Hexachlorobenzene
Pentachlorophenol
Pentachloronitrobenzene
Chlorobenzilate
3, 3 '-Dichlorobenzidine
0.0
6.0
49.1
52.0
56.4
58.9
53.2
63.3
59.8
64.1
60.9
56.1
60.1
74.0
44.8
59.5
65.4
60.1
56.0
42.3
49.8
62.7
44.6
42.4
43.4
40.7
4.4
128 1
37.5
352s
37 T2
369*
372*
35 12
37 62
35. 32
34.7s
352s
36 S2
369s
360
35 T2
43. 12
36 S2
40 T2
61 8
470
432*
339
41 5
379
506
1649
Chloroacetic acid could not be analyzed by the SemiVOST methodology.
Acceptable performance by the analyte in the SemiVOST method, using acceptability criteria of 50-150% recovery, with Percent Relative Standard Deviation of 50 or less.
. GOVERNMENT PRINTING OFFICE: 1993 - 750-071/80076
-------
-------
-------
J.F. McGaughey, J.T. Bursey, and R.G. Merrill, Jr., are with Radian Corporation,
Research Triangle Park, NC 27709.
Merrill D. Jackson is the EPA Project Officer (see below).
The complete report, entitled "Field Test of a Generic Method for Halogenated
Hydrocarbons," (Order No. PB93-212181AS; Cost: $36.50, subject to change)
will be available only from:
National Technical Information Service
5285 Port Royal Road
Springfield, VA 22161
Telephone: 703-487-4650
The EPA Project Officer can be contacted at:
Atmospheric Research and Exposure Assessment Laboratory
U.S. Environmental Protection Agency
Research Triangle Park, NC 27711
United States
Environmental Protection Agency
Center for Environmental Research Information
Cincinnati, OH 45268
Official Business
Penalty for Private Use $300
BULK RATE
POSTAGE & FEES PAID
EPA
PERMIT NO. G-35
EPA/600/SR-93/101
------- |