A trace analysis of oxytetracycline and tetracycline residues in pasteurized milk supplied in Tehran: a one-year study (April 2011-March 2012)

Rasooli, Ali; Amani, Zahra; Bahonar, Alireza; Shams, Gholamreza; Abdolmaki, Zohreh

doi:10.22059/ijvm.2014.51409

A trace analysis of oxytetracycline and tetracycline residues in pasteurized milk supplied in Tehran: a one-year study (April 2011-March 2012)

Authors

Ali Rasooli ¹

Zahra Amani ¹

Alireza Bahonar ²

Gholamreza Shams ¹

Zohreh Abdolmaki ¹

¹ Department of Pharmacology, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran

² Department of Food Hygiene and Quality Control, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran

10.22059/ijvm.2014.51409

Abstract

BACKGROUND: Tetracyclines (TCs) are broad-spectrum
antibiotics that are widely used in veterinary medicine. The
presence of TCs residues in milk is a public health concern all
over the world. OBJECTIVES:This study aimed to determine TCs
residuals in pasteurized milk marketed by some dairy companies
in Tehran from April 2011 to March 2012. METHODS: 432
pasteurized milk samples were purchased from supermarkets
supplying the milk products of 12 major dairy companies in
Tehran (3 samples from each company every month), and they
were stored at -20 0C until analysis. Oxytetracycline (OTC) and
Tetracycline (TC) residues in each sample were extracted by a
liquid - liquid phase procedure and quantitated using a high
performance liquid chromatographic (HPLC) method. Chromatographic
conditions included a mobile phase as oxalic acid
buffer- acetonitril (80: 20) with a flow rate of 1mL/min and UVdetection
at 355 nm. RESULTS: TCs residuals in most milk
samples were lower than 100 ppb, maximum residue level
(MRL); however, in seven samples (1.62%) the total residues of
OTC and TC were more than MRL. In the latter milk samples, the
median total TCs residue was 625 ppb, ranging between 274 and
1270 ppb. CONCLUSIONS: Because of the presence of TC
residues above the MRL level in a limited number of milk
samples, it is concluded that more studies and supervision of
health authorities are needed in this field.

Keywords

HPLC

Milk

residue

tetracyclines