United States
Environmental Protection
Agency
Environmental Sciences Division
P.O. Box 93478
Las Vegas, NV 89193-3478
March 1999
OFFICE OF RESEARCH AND DEVELOPMENT
TECHNOLOGY SUPPORT PROJECT
vvEPA Mobile
Mass
Spectrometry
Environmental
Technology
Verification
GC/MS in
the Field
The Study
Verification
The U.S. Environmental
Protection Agency, through its
Environmental Technology
Verification (ETV) Program,
works on accelerating the
acceptance and use of
improved methods for envi-
ronmental analysis. Recent-
ly, scientists at the EPA
National Exposure Research
Laboratory, Environmental
Sciences Division (ESD) in
Las Vegas, conducted two
studies to evaluate the per-
formance of field-portable gas
chromatograph/mass
spectrometer (GC/MS)
equipment.
Working with instrument
developers and an indepen-
dent testing organization (in
this case, Sandia National
Laboratory, Albuquerque),
ESD scientists designed an
evaluation study wherein the
two candidate technologies
were evaluated against an
approved reference method.
The accuracy, precision, and
comparability of each
instrument was assessed
based on results obtained for
performance evaluation (PE),
spiked, and environmental
samples.
GC/MS is an EPA recom-
mended method for the
analysis of volatile and
semivolatile organic com-
pounds. This proven analy-
tical technique identifies and
quantifies organic compounds
on the basis of molecular
weight, characteristic
fragmentation patterns, and
retention time of the
chromatographic column.
Until relatively recently, it was
not feasible to bring a GC/MS
instrument to a hazardous
waste site because of its size
and weight, the need for strict
control of temperature and
humidity, and the effect of
vibration during transport.
With the growing demand for
field-portable instrumentation
in environmental analysis,
rugged, smaller units, like the
two in this study, have been
developed.
Field-transportable GC/MS is
a versatile technique that can
be used to provide rapid
screening data or laboratory
quality confirmatory analyses.
In most systems, the
instrument configuration can
be quickly changed to
accommodate different inlets
for media such as soil, soil
gas, and water.
Two sites were selected for
evaluating the instruments for
measurement of several
compounds: the U.S.
Department of Energy
Savannah River Site in South
Carolina (for trichloroethene
and tetrachloroethene), and
Wurtsmith Air Force Base in
Michigan (for benzene,
toluene, xylenes, and
chlorinated organic solvents).
In addition to the different
contaminants present, these
sites also provided different
climatic and geological
conditions to test the
ruggedness and versatility of
the instruments.
The two portable GC/MS
instruments evaluated in this
verification study were: the
Viking SpectraTrak™ 672 and
the Bruker-Franzen EM640™.
The reports cited at the end of
this fact sheet provide details
of the studies and their
results.
Six features were considered
for each of the instruments:
throughput
(samples/increment of time),
completeness (% of target
compounds detected),
precision (relative percent
difference for series of
duplicates from each
medium), accuracy (proximity
to the known concentration),
comparability (against
contract laboratory results),
and deployment (field
ruggedness, setup time, and
other ease-of-use factors).
Specific results for each of the
instruments is available in the
reports cited below.
197CMB98.FS-24 • Rev. 4/8/99
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References W. Einfeld, S. F. Bender, M. R. Keenan, S. M. Thornberg, and M. M. Hightower, EPA/600/R-97/148,
U.S. Environmental Protection Agency, Washington, D.C., 1997. (Viking Instruments Corporation
SpectraTrak™672)
W. Einfeld, S. F. Bender, M. R. Keenan, S. M. Thornberg, and M. M. Hightower, EPA/600/R-97/149,
U.S. Environmental Protection Agency, Washington, DC, 1997. (Bruker-Franzen Analytical
Systems, Inc., EM640™)
For Further For technical information regarding field-
Information portable GC/MS, or for information about the
Environmental Technology Verification
Program, contact:
Dr. Stephen Billets, Jr.
U.S. Environmental Protection Agency
National Exposure Research Laboratory
Environmental Sciences Division
P.O. Box 93478
Las Vegas, NV 89193-3478
Tel: (702) 798-2232
For information about the Technology Support
Center at the ESD, contact:
Mr. J. Gareth Pearson, Director
U.S. Environmental Protection Agency
National Exposure Research Laboratory
Environmental Sciences Division
P.O. Box 93478
Las Vegas, NV 89193-3478
Tel.: (702) 798-2270
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The Technology Support Center fact sheet series is developed and written by Clare L. Gerlach, Lockheed
Martin, Las Vegas.
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