Table 15. MDLs (g/L) for some target
Combined use of GC-ECD and HPLC will pro-
analytes when 1-L water samples were
vide an improved method for analyte confirmation
preconcentrated to 4.0 mL acetonitrile
because chromatographic separations are based on
using cartridge and disk solid-phase ex-
different physical properties (vapor pressure and
traction.
polarity) and the detectors are based on different
principles (electronegativity and UV absorption).
Spiked
This method is under review by the EPA Office
conc.
MDLs* by GC-ECD
(g/L)
Cartridge
Disk
in Water by Gas Chromatography.
DNB
0.01
0.004
0.003
2,6-DNT
0.01
0.003
0.003
2,4-DNT
0.01
0.009
0.01
TNB
0.01
0.007
0.003
LITERATURE CITED
0.02†
TNT
0.01
0.01
0.02†
RDX
0.01
0.004
ATSDR (1997) U.S. Department of Health and Hu-
4-Am-2,6-DNT
0.01
0.003
0.003
man Services, Atlanta, Georgia, Agency for Toxic
2-Am-4,6-DNT
0.01
0.003
0.004
Substances and Disease Registry Database (http://
Tetryl
0.01
0.009
0.01
ATSDR1.ATSDR.cdc.gov:8080).
HMX
0.01
0.004
0.008
Belkin, F., R.W . Bishop, and M.V. Sheely (1985)
* Data in Table A2.
Analysis of explosives in water by capillary gas
† MDLs are greater than spiked concentration and
chromatography. Journal of Chromatographic Science,
therefore are not valid.
24: 532534.
phases, and the volume of water preconcentrated is
Burrows, E.P., D.H. Rosenblatt, W.R. Mitchell, and
more likely limited by practical considerations such
D.L. Palmer (1989) Organic explosives and related
as time or possible plugging of the solid phase.
compounds: Environmental and health considera-
tions. U.S. Army Biomedical Research and Develop-
ment Laboratory, Fort Detrick, Maryland, Report
CONCLUSIONS
Number 8901.
A gas chromatographic method for the deter-
Department of the Army (1984) Military Explosives.
mination of explosives in water was developed to
Washington, D.C., TM 9-1300-214.
serve as an alternative to and/or complement the
Feltes, J., K. Levsen, D. Volmer, and M. Spieker-
current HPLC SW-846 Method 8330. Water sam-
mann (1990) Gas chromatographic and mass spec-
ples are preconcentrated using SPE, and the aceto-
trometric determination of nitroaromatics in water.
nitrile extracts are directly injected onto a short (6
Journal of Chromatography, 518: 2140.
m) DB1 analytical column. High linear carrier
Grant, C.L., A.D. Hewitt, and T.F. Jenkins (1991) Ex-
gas velocities resulted in higher peak heights for
perimental comparison of EPA and USATHAMA
the nitramines and nitrate esters, the most ther-
detection capability estimators. American Laborato-
mally labile analytes. MDLs ranged from 0.04 to
ry, February, p. 1533.
0.4 g/L when 0.5 L of water samples was precon-
Grob, K. (1994) Injection techniques in capillary
centrated to 5.0 mL acetonitrile. Lower MDLs for
GC. Analytical Chemistry, 66(20): 1009A1019A.
some analytes, such as 2,6-DNT, were obtained by
Hable, M., C. Stern, C. Asowata, and K. Williams
preconcentrating a larger volume of water.
(1991) The determination of nitroaromatics and
Analysis of extracts from field samples showed
nitramines in ground and drinking water by wide-
good agreement between the GC-ECD and the
bore capillary gas chromatography. Journal of Chro-
standard HPLC method.
matographic Science, 29: 131135.
Potential advantages over the current HPLC
Hashimoto, A., H. Sakino, E. Yamagami, and S.
method include lower detection limits, improved
Tateishi (1980) Determination of dinitrotoluene iso-
chromatographic resolution, and the utilization of
mers in sea water and industrial effluent by high-
instrumentation most commonly found in envi-
resolution electron-capture gas chromatography
ronmental labs. Disadvantages of the GC method
with a glass capillary column. Analyst, 105: 787
include nonlinear calibration, limited dynamic
793.
range of the detector, and increased attention to
Hass, R., I. Schreiber, E.v. Lw, and G. Stork (1990)
instrument maintenance (i.e., frequent changes of
Conception for the investigation of contaminated
the injection-port liner). Also, the low concentra-
munition plants 2. Investigation of former RDX-
plants and filling stations. Fresenius' Journal of Anal-
frigeration to maintain analyte stability.
ytical Chemistry, 338: 4145.
17
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