Identification of antibiotic residues in chicken meat samples in Bolivia, Ghana, Italy, and Nepal

Objectives: The study aimed to qualitatively determine the presence of antibiotic residues in retail chicken meat samples. Materials and Methods: A multicenter cross-sectional study was conducted in urban areas of Bolivia, Ghana, Italy, and Nepal, selecting chicken samples from the common sales outlets. The analysis was performed in two steps. First, a screening analysis using a rapid microbiological test. Subsequently, the positive samples, along with a randomly selected subset of screening-negative samples, were analyzed using analytical HPLC and ESI-MS spectrometry. Results: A total of 352 chicken breast samples were collected and analyzed. The initial screening detected antibiotic residues in seven samples from Bolivia (n = 7/76; 9.2% of Bolivia) and three from Nepal (n = 3/95; 3.2% of Nepal). The antibiotic residues in retail chicken meat samples in Ghana and Italy were below the detection limits. Subsequent qualitative HPLC analysis-based on retention time matching-identified amoxicillin and oxytetracycline, a finding confirmed by mass spectrometry. Some samples that tested negative in screening were found to contain residues during HPLC analysis, likely because their concentrations were below the assay's limit of detection. Conclusions: Effective surveillance systems are needed to detect antibiotic residues in foods of animal origin, alongside strategies to mitigate the health risks posed by antimicrobial resistance.