Table 5. Set 3, trial 3. Mean and standard deviations of triplicate
analyte concentrations of spiking solution (g) and of analyte
concentrations (g/g) for preserved and unpreserved samples
stored at 22 and 4C.
Treatment aliquot
Treatment aliquot
(g)
(g)
Analyte
Analyte
120.7
3.40.2
CDCE
iso-PB
8.90.1
2.80.2
C-tet
n-PB
130.3
4.40.1
1,2 DCP
1,3 DCB
7.41.0
0.810.21
Styrene
n-BB
Storage period
0†
Analyte
Day
Day 3
Day 6
Day 13
Day 28
A. 22C--unpreserved (g/g)
110.4
110.6
9.70.7
7.71.0
7.20.3
CDCE
8.20.4
7.90.5
7.30.7
6.81.0
6.11.5
C-tet
120.4
120.6
120.3
9.10.6
100.5
1,2 DCP
5.90.2
Styrene
ND
ND
ND
ND
2.40.2
0.070.07
iso-PB
ND
ND
ND
1.70.2
0.040.03
n-PB
ND
ND
ND
2.70.1
2.10.2
2.10.1
1.60.1
1.90.1
1,3 DCB
0.300.09
0.030.02
n-BB
ND
ND
ND
B. 4C--unpreserved (g/g)
110.4
110.2
110.5
110.3
110.2
CDCE
8.20.4
7.80.5
8.00.1
8.00.2
7.80.6
C-tet
120.4
120.2
120..2
120.4
130.3
1,2 DCP
5.90.2
5.30.1
5.50.1
4.60.1
Styrene
ND
2.40.2
2.10.1
2.10.1
1.90.1
iso-PB
ND
1.70.2
1.40.1
1.50.1
1.20.1
n-PB
ND
2.70.1
2.30.1
2.40.1
2.30.1
2.40.1
1,3 DCB
0.300.09
0.210.01
0.230.01
0.160.01
0.020.02
n-BB
C. 22C--preserved with NaHSO 4 (g/g)
130.4
130.6
120.5
120.4
120.2
CDCE
8.80.2
8.50.3
8.40.3
8.40.6
8.50.2
C-tet
140.1
140.6
140.3
130.2
140.6
1,2 DCP
2.40.8
0.500.12
0.570.10
0.330.12
0.120.12
Styrene
2.50.1
2.20.3
2.30.1
2.20.1
2.10.1
iso-PB
1.80.1
1.50.2
1.60.1
1.50.1
1.40.1
n-PB
2.60.1
2.20.3
2.20.1
2.10.1
2.00.1
1,3 DCB
0.280.04
0.220.03
0.220.01
0.230.01
0.200.01
n-BB
* ND = not detected, less than 0.02 g of VOC/g
† Same set used for day 0 values for unpreserved samples.
ous extraction in preparation for static HS/GC
theory, a second experiment with the set 1 ana-
lytes was performed, but a two-day period of
analysis. Losses of similar magnitude (<35%) may
refrigerated (4C) storage was allowed between
also have occurred for the aromatic hydrocarbons
in these first three trials.
treatment and the initial analysis. This additional
holding period allowed the analytes to equilibrate
All of the soil samples prepared in this study
(sorb) with the organic carbon present in the soil.
had a moisture content of 24% after treatment and
were exposed to approximately 2.5 cm3 of air dur-
Comparing Tables 3 and 6 (Fig. 46 vs. 79) shows
that while there is often a decreasing trend of the
ing storage in the 2-mL glass ampoules. This mois-
trichloroethylene (TCE) and perchloroethylene
ture and oxygen content is sufficient to allow for
(PCE) concentrations in trial 1, this did not occur
the aerobic microbial degradation of the VOCs
in trial 4. Based on this finding, the decreases in
(Atlas 1981). Correspondingly, the soil subsam-
ples held at room temperature (22C), showed a
analyte concentrations for the chlorinated com-
pounds in trials 1 through 3 can be partly attributed
complete (>95%) loss of the aromatic hydrocarbons
to slow sorption by the organic matter in soil.
within nine days (Fig. 4, 10 and 11). Indeed, among
This process is not readily reversed by aque-
the analytes in the first three sets, with the excep-
7
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