Environmental Engineering Reference
In-Depth Information
Fig. 3
LC-MS/MS total ion chromatogram resulting from analysis of clean tissue spiked with
a mixture of pharmaceutical standards. Peak identifications are as follows: (1) acetaminophen-
d4, (2) acetaminophen, (3) atenolol, (4) cimetidine, (5) codeine, (6) 1,7-dimethylxanthine, (7)
lincomycin, (8) trimethoprim, (9) thiabendazole, (10) caffeine, (11) sulfamethoxazole, (12) 7
aminoflunitrazepam-d7
7
(
+
IS), (13) metoprolol, (14) propranolol, (15) diphenhydramine-d
3
,
(16) diphenhydramine, (17) diltiazem, (18) carbamazepine-d
10
, (19) carbamazepine, (20) tylo-
sin, (21) fluoxetine-d6,
6
, (22) fluoxetine, (23) norfluoxetine, (24) sertraline, (25) erythromycin,
(26) clofibric acid, (27) warfarin, (28) miconazole, (29) ibuprofen-
13
C
3
, (30) ibuprofen, (31)
meclofenamic acid (-IS), and (32) gemfibrozil.
Data source
Ramirez et al. (
2007
)
isocratic hold (93:7 formic acid-methanol) was added to the end of each run to
allow for column equilibration between injections. While the majority of analytes
were eluted as single peaks, erythromycin was consistently eluted as two partially
resolved peaks, which are attributed to differing retention characteristics for pre-
sumed Stereoisomers (Vanderford et al. 2003; Yang and Carlson 2004). In addition,
isotope effects on retention behavior were often observed for carbamazepine-
d
10
and
fluoxetine,
d
6
(peaks 18 and 19, Fig.
3
). The observed retention time for carbamaze-
pine-
d
10
(30.08 min) was shorter than that observed for carbamazepine (30.53 min)
by almost 30 s. Correspondingly, a 20-s difference in retention time was observed
for fluoxetine
d
6
(34.58 min) relative to that observed for fluoxetine (34.93 min),
although it is not evident in Fig.
3
due to coelution of norfluoxetine (35.13 min).
Finally, isotope effects were not observed for acetaminophen (peaks 1 and 2) and
diphenhydramine (peaks 15 and 16, Fig.
3
) due to a lower degree of deuterium sub-
stitution and decreased resolution at shorter retention times. Four compounds such as
diphenhydramine, diltiazem, carbamazepine, and norfluoxetine were detected in fish
environmental samples (affected by contaminants; Fig.
4
a), which were confirmed by
comparing the results of the fish samples unaffected by contaminants and spiked with
known amounts of their respective standards (Fig.
4
b). The concentrations of these
pharmaceuticals were 0.66-1.32 ng g
−
1
for diphenhydramine, 0.11-0.27 ng g
−
1
for
diltiazem, 0.83-1.44 ng g
−
1
for carbamazepine, and 3.49-5.14 ng g
−
1
for norfluox-
etine detected in 11 of 11 contaminated environmental fish samples.
