Page 34 - Volume 5, Issue 2, July 2012

© Benaki Phytopathological Institute
Dithiocarbamates and inorganic bromide residues in plant products 63
centrations of Br were determined, almost
twice the MRL of 50mg/kg.
Conclusions
Dithiocarbamate fungicides belong to the
most extensively used fungicides in agricul-
ture. Because of poor solubilities of dithio-
carbamates in common organic and aque-
ous solvents and, additionally, the lack of
stability during homogenization of plant
samples, the acid treatment of the whole
sample (or large segments), evolving CS2 as
analyte in the process of gas chromatogra-
phy determination with flame photometric
detector (FPD) with sulphur filter seems to
be most effective.
Inorganic bromide is the degradation
product of fumigants or other pesticides
used for post-harvest treatment. Not many
laboratories analyse plant products for this
compound. High bromide concentrations
were determined in rice samples obtained
from the market. Rice is a product that has
been through processing before reaching
the shelf and the detection of bromide resi-
dues in a processed product justifies the ne-
cessity for elaborating the validation of such
a specialized analytical method.
The two methods are characterized by
good accuracy, precision and sensitivity and
are considered as suitable for routine analy-
sis in accordance to the requirements of Eu-
ropean Commission. Our findings contribute
to our goal to develop and validate the vast
majority of single residue methods in order
to monitor domestic and imported samples
for analytes that are not able to be detected
with the multi residue methods usually ap-
plied by most laboratories and thus ensure
food safety and quality.
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