University of Tehran Iranian Journal of Veterinary Medicine 2251-8894 8 2 2014 08 01 A trace analysis of oxytetracycline and tetracycline residues in pasteurized milk supplied in Tehran: a one-year study (April 2011-March 2012) ردیابی کمّی بقایای اکسی تتراسایکلین و تتراسایکلین در شیرهای پاستوریزه مصرفی شهر تهران در طول سال 1390 119 123 51409 10.22059/ijvm.2014.51409 EN Ali Rasooli Department of Pharmacology, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran 0000-0001-6591-2404 Zahra Amani Department of Pharmacology, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran Alireza Bahonar Department of Food Hygiene and Quality Control, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran Gholamreza Shams Department of Pharmacology, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran Zohreh Abdolmaki Department of Pharmacology, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran Journal Article 2013 12 18 BACKGROUND: Tetracyclines (TCs) are broad-spectrum<br />antibiotics that are widely used in veterinary medicine. The<br />presence of TCs residues in milk is a public health concern all<br />over the world. OBJECTIVES:This study aimed to determine TCs<br />residuals in pasteurized milk marketed by some dairy companies<br />in Tehran from April 2011 to March 2012. METHODS: 432<br />pasteurized milk samples were purchased from supermarkets<br />supplying the milk products of 12 major dairy companies in<br />Tehran (3 samples from each company every month), and they<br />were stored at -20 0C until analysis. Oxytetracycline (OTC) and<br />Tetracycline (TC) residues in each sample were extracted by a<br />liquid - liquid phase procedure and quantitated using a high<br />performance liquid chromatographic (HPLC) method. Chromatographic<br />conditions included a mobile phase as oxalic acid<br />buffer- acetonitril (80: 20) with a flow rate of 1mL/min and UVdetection<br />at 355 nm. RESULTS: TCs residuals in most milk<br />samples were lower than 100 ppb, maximum residue level<br />(MRL); however, in seven samples (1.62%) the total residues of<br />OTC and TC were more than MRL. In the latter milk samples, the<br />median total TCs residue was 625 ppb, ranging between 274 and<br />1270 ppb. CONCLUSIONS: Because of the presence of TC<br />residues above the MRL level in a limited number of milk<br />samples, it is concluded that more studies and supervision of<br />health authorities are needed in this field. https://ijvm.ut.ac.ir/article_51409_42f48ee75844ae277cf0a5ac4b5bf8b1.pdf