80
and placed in new vials filled to capacity with
blank reagent-grade water. The vials were in-
2ADNT
verted to ensure that solution contacted the cap
liner, and they were held under refrigeration for
2ADNT
36 days. At 7, 19, and 36 days, a small portion of
the water was withdrawn and analyzed. Detect-
60
able concentrations of the three isomers of ni-
4ADNT
trotoluene were found, and the concentrations
increased as exposure times increased (Table 7).
3,5-DNA
Cap liners from the 64-day acidified samples
4ADNT
were rinsed with reagent-grade water and placed
40
in new vials containing 2 mL of acetonitrile and
3,5-DNA
inverted to extract sorbed analytes. These sam-
ples were stored overnight in the dark at room
Control
temperature. Detectable concentrations of the
Acidified
three isomers of mononitrotoluenes, NB, and the
20
two isomers of the dinitrotoluenes were found
0
20
40
60
Storage Time (days)
(Table 7). The percentage recovery ranged from
21 to 70% of the mass lost from the water for the
Figure 12. Stability of 2ADNT, 4ADNT, and 3,5-DNA in
various compounds. Thus, sorption by the cap
fortified Connecticut River water as a function of storage
liners appears to be responsible for the slow
time for samples acidified to pH 2 or left unacidified.
losses of the nitrotoluenes and nitrobenzene ob-
served and accounts for the loss of the dinitro-
toluenes from acidified samples as well.
200
Control
Table 7. Recoveries of analytes from polyethyl-
Acidified
ene cap liners (0.44 cm3).
160
Mass of analytes recovered when caps (day 28) were
equilibrated with reagent-grade water for various lengths
of time.
4NT
Mass (g) recovered
Day 7
Day 19
Day 36
120
C/A*
C/A
C/A
2NT
0.18/0.15
0.18/0.19
0.19/0.21
3NT
0.15/0.11
0.17/0.15
0.21/0.19
4NT
0.31/0.37
0.55/0.57
0.65/0.64
80
* C/A--Control/Acidified
2NT
Mass of analytes recovered when caps (day 64) were ex-
tracted for 18 hours with ACN.
3NT
40
Mass of analyte lost
Mass of analyte recovered
NB
from solution (g)
from cap liners (g)
2NT
0.56
0.20
3NT
0.48
0.10
4NT
1.17
0.32
0
20
40
60
Storage Time (days)
NB
0.14
0.06
Figure 13. Stability of 2NT, 3NT, 4NT, and NB in fortified
2,4-DNT
0.10
0.06
Connecticut River water as a function of storage time for
2,6-DNT
0.10
0.07
samples acidified to pH 2 or left unacidified
15
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