Oxytetracycline residues in retail chicken eggs in Ibadan, Nigeria

Oxytetracycline residues in chicken eggs from five markets within Ibadan metropolis were determined by high-performance liquid chromatography following solid-phase extraction. Recovery of oxytetracycline was 80.5%-87.8%, whereas 75.2% of the samples contained detectable oxytetracycline with an overall mean residue concentration of 479.0 µg kg(-1). Residue concentrations from Iwo Road, Apata, Challenge, Ojoo and Bodija markets were 421, 460, 468, 568 and 476 µg kg(-1), respectively. Eggs from Ojoo market had the highest levels, whereas 68.8% of the samples contained residues above the Codex Alimentarius Commission maximum residue limit. The results are of public health interest as they indicate that a greater proportion of eggs being consumed in Ibadan could contain residues above the maximum residue limit, for which unregulated access and indiscriminate use of antibiotics by poultry farmers could be responsible. National surveillance of eggs and other animal products for antibiotic residue and appropriate regulation of antibiotic is recommended to ensure food safety for consumers.