Agriculture Reference
In-Depth Information
O
CH
O
3
CH
3
S
S
2-ITX
4-ITX
H
3
C
CH
3
CH
2
O
H
2
C
O
CH
3
O
P
O
H
3
C
O
CH
3
O
H
3
C
CH
3
O
O
H
3
C
CH
3
O
CH
3
Irgacure
H
3
C
TRP
Figure 4.4.
Chemical structures of photoinitiators found in food.
using reversed-phase chromatography on a C18 column (e.g., Hypersil BDS C18
column (5
2 mm)) with a gradient of water to acetonitrile containing formic
acid. The sensitivity levels of the ABSCIEX 3200 QTRAP
LC
m, 100
×
μ
MS/MS system
(a midrange system) were high enough to detect migrants at 0.01mg/kg in extracts
from packaging material by direct injection of the extracts [43].
Contamination of infant formula not only occurs via labeling but also comes from
chemical migration from baby bottle teats. The contaminants of this group include
N
-
nitrosamines that originate from the various dialkyl amines that are used as accel-
erators and stabilizers in the vulcanization process of the rubber used for the teats.
These compounds have been shown to have signi
-
cant health effects on infant
ingestion. Traditional methodology used detection by GC analysis [44], but this
approach suffers from several drawbacks, the most signi
cant being the inability to
identify the peak of interest due to coeluting or masking matrix peaks. Therefore,
methods have been developed to detect these contaminants by LC
MS/MS. Several
different
N
-nitrosamines have been reportedly found in rubber teats and they include
N
-nitrosomethylethylamine and
N
-nitrosodimethylamine (Table 4.1). In this case,
detection is done by APCI in negative mode and the HPLC separation is again by
reversed-phase chromatography. Because APCI was used, no HPLC modi
-
ers are
needed to boost sensitivity and a simple methanol gradient can be employed [45].
The MRM transitions used are shown in Table 4.1 and detection levels at low
g/kg
μ
can be easily achieved.
Probably the largest group of migrants is phthalates. The issue of phthalates in food
was brought to the attention of the Directorate General for Health and Consumers (DG
SANCO) in 2007 [46]. Phthalates (1,2-benzenedicarboxylic acid esters) are a group of
