Determination of 0xytetracycline and Sulphamethazine Residues In Marketed Beef From Selected Parts of Zambia To Assess Compliance With Maximum Residual Limits

Abstract

A cross-sectional study was conducted to determine the levels of oxytetracycline (OTC) and sulphamethazine (SMZ) antimicrobial residues and assess compliance with maximum residual limits (MRL) in beef from selected provinces of Zambia. A total of 224 muscle samples were randomly collected from abattoirs/butcheries from; Central (n = 48),Copperbelt (n = 64), Lusaka (n = 82) and Southern (n = 30) provinces. Samples were analyzed using high performance liquid chromatography (HPLC) coupled with a Diode Array Detector (DAD). Results showed that 77 (34.4%; 95% CI: 28.4 - 40.9) and 39 (17.4%; 95% CI: 12.9 - 22.9) of samples contained detectable antimicrobial residues of OTC (Range: 27.26 – 481.61 ng/g, mean = 199.6 ± 46 ng/g) and SMZ (Range: 11.92 – 259.98 ng/g, mean = 86.5± 8.7 ng/g), respectively. About 45.5 percent and 12.8 percent of the samples contained OTC and SMZ residues, respectively, that were above the Codex Alimentarius Commission’s MRL. Similarly, 76.6 percent and 33.3 percent of the samples contained OTC and SMZ residues, respectively, above the European Union MRL. The higher levels of the drug residues detected were probably due to failure by farmers to observe the drug withdraw period and posed a threat of development of antimicrobial resistance in foodborne pathogens and probable risk to human health.