Detection of cyromazine and melamine residues in poultry eggs
Abstract
Cyromazine (CYR) is an insect growth regulator for fly control at animal farms. It is used as a
feed additive in layer farms so that it gets excreted in the droppings of the birds and exert its larvicidal
activity in the manure. However, due to this practice, residues of CYR and its metabolite melamine
(MEL) also appear in the eggs. A new instrumental method was developed for separation and detection
of CYR and MEL on HPLC-UV system. The mobile phase comprised of ACN and 0.05% TFA at pH
2.5 was applied in gradient mode at a flow rate of 1 mL/min. A new method using anhydrous
magnesium sulfate, calcium silicate, celite 545 as adsorbents and acidified acetonitrile as extraction
solvent was developed for extraction and clean up of CYR and MEL residues in eggs which was found
to be quick, easy, cheap, effective, rugged and safe (QuEChERS). The LOD and LOQ of the method
was found to be 5.3 and 16.0 µg/kg for CYR and 11.4 and 34.7 µg/kg for MEL, respectively. The
accuracy of the method ranged between 84-103 % and precision of the method remained less than 5 %
RSD. Linearity studies of spiked sample showed the consistent performance of the method at various
concentrations (R²>0.996). A total of 110 egg samples were collected from 52 farms located in 5
different districts of Haryana (Panchkula, Ambala, Panipat, Sirsa and Hisar) and analyzed for the
presence of CYR and MEL by applying newly developed QuEChERS method. The mean concentration
of the CYR was found to be 42.71 µg/kg with a range of 16.88 -112.61 µg/kg. MEL was not detected
in any of the sample analyzed. Estimates of dietary exposure of CYR through consumption of eggs for
population in Haryana was found to be 33.40 µg/kg b.w./day which contributed 0.55 % of ADI of
CYR. A cross-sectional study was carried out in 52 layer farms situated in 5 districts (Panchkula,
Ambala, Panipat, Sirsa and Hisar) of Haryana, India to identify the risk factors associated with the
usage of CYR revealed that, factors such as cleanliness practices, number of birds kept at the farm and
fly density in the farm were significantly associated with the CYR usage in feed for the purpose of fly
control. The findings of the present study suggested that 57.69 % farmers had knowledge of CYR and
are adding it in the feed of layers as larvicidal agent. Further it was observed that 66.67 % farmers
(n=30) use CYR above the recommended levels. Data analysis revealed that factors such as cleanliness
practices at the farm (OR: 5.143, 95% CI: 1.403-18.858), number of birds kept at the farm (OR:
17.417, 95% CI: 4.307-75.146) and fly density in the farm (OR: 6.22, 95% CI: 1.836-21.090) were
significantly associated with CYR usage in the layer farms.