Detection of penicillin and tetracycline residues in pork and beef meat using ELISA

Public health concerns are raised by the increased use of antibiotics in livestock and antibiotic residues in animal-derived foods. The most likely reasons for drug residues are the indiscriminate and inappropriate drug use and failure to adhere to withdrawal periods. The aim of this research was to determine the levels of two groups of antibiotics (penicillins and tetracyclines) in pork and beef meat samples. A total of 80 raw pork and beef meat samples were collected from retail stores, processing plants and a slaughterhouse in different regions across Bulgaria and analysed by an enzyme-linked immunosorbent assay (ELISA). Penicillin was detected in 4.88% of pork samples and 7.69% of beef samples, with concentrations varying between 5.74 and 12.69 µg/kg for pork and 8.19 and 10.64 µg/kg for beef, respectively. Tetracycline was detected in 21.95% of pork samples and 5.13% of beef samples, with a range of 1.51 to 3.29 µg/kg for pork and 2.28 to 3.67 µg/kg for beef samples. None of the tested meat samples exceeded the legal limits for penicillin (50 µg/kg) and tetracycline (100 µg/kg). The results showed that meat from retail shops, processing plants and a slaughterhouse in Bulgaria contained low levels of penicillin and tetracycline and therefore posed a low risk to public health. However, the presence of veterinary drugs in animal foods is a major food safety issue and requires continuous regulation of antibiotic concentrations.