Assessment of Enrofloxacin residues in table eggs obtained from open markets and supermarkets in Lusaka province of Zambia

Abstract

Globally, table eggs represent a vital dietary source. Unfortunately, antibiotic residue (AR) contamination in eggs remains a substantial food safety and public health concern. While the presence of antibiotic residues in poultry products is a known problem, there is still limited data, particularly with regard to the use of antibiotics that are prohibited in the production of poultry eggs. Herein, we used High-Performance Liquid Chromatography (HPLC) to determine the proportional distribution of branded and unbranded table eggs from supermarkets (regulated retail outlets) and open markets (traditional, informal markets) in Lusaka province that would contain enrofloxacin residues. Of the total samples tested, 31.7% (95% CI: 20.3-44.9%) contained enrofloxacin residues ranging from 0.16 to 1.52 µg/g. A higher proportion of the enrofloxacin residues were detected in open markets, 84.2% (95% CI: 60.4-96.6%), compared to supermarkets, 15.8% (95% CI: 3.4- 39.6%). Similarly, the majority of enrofloxacin residues were detected in unbranded eggs, 89.5% (95% CI: 66.9-98.7%), compared to branded eggs, 10.5% (95% CI: 1.3-33.1%). Given the high risk of AR in Zambia and many other countries globallywhich is associated with extensive use of antibiotics in poultry, our data contributes to a fundamental knowledge gap and is relevant in generating hypotheses that will guide future research and developing targeted public health interventions to minimise human exposure to antibiotic residues.