Oxytetracycline and Suphamethazine residues in marketed beef in Zambia

A cross-sectional study was conducted to determine levels of oxytetracycline and sulphamethazine residues and assess compliance with maximum residue limits in beef from selected provinces of Zambia. 224 samples were collected from abattoirs in; Central, Copperbelt, Lusaka and Southern provinces. Samples were analyzed using high-performance liquid chromatography- Diode Array Detector. Results showed that 34.4% (95% CI: 28.4-40.9) and 17.4% (95% CI: 12.9-22.9) of samples contained residues of oxytetracycline (Range: 27.26 - 481.61 ng/g, mean = 199.6 ± 46 ng/g) and sulphamethazine (Range: 11.92 - 259.98 ng/g, mean = 86.5 ± 8.7 ng/g), respectively.45.5% and 12.8% of samples contained oxytetracycline and sulphamethazine residues that were above the Codex Alimentarius Commission's MRL. Similarly, 76.6% and 33.3% samples contained oxytetracycline and sulphamethazine residues above the European Union MRL. The higher levels of residues detected were due to failure by farmers to observe drug withdraw periods and posed a threat of development of antimicrobial resistance in foodborne pathogens and risk to human health.