Occurrence and health risk assessment of β-lactam antibiotic residues in chicken meat from Kiambu County, Kenya

Abstract

Antibiotic pharmaceuticals are used to treat bacterial diseases in both humans and livestock. In poultry farming, they are used not only to treat and prevent diseases but also to promote growth. However, their overuse increases antibiotic resistance, posing significant global concerns for both humans and the environment. In Kenya, humans' exposure levels to antibiotic residues from consuming animal products has been scarcely explored. This study determined the occurrence of penicillins and cephalosporins in chicken meat and evaluated the associated human health risks. A total of 100 chicken meat samples were collected from chicken farmers and vendors in Kiambu County, including 56 broilers, 24 ex-layers, and 18 indigenous samples. The samples were prepared for antibiotic analysis using the Quick-Easy-Cheap-Effective-Rugged-Safe (QuEChERS) method and quantified by Ultra-Performance Liquid Chromatography-Mass Spectrometry. Recoveries ranged from ‘72.5–98.9 %’. Among the penicillins, ampicillin residues were the most predominant, particularly, in broiler breast tissues, with concentrations of up to 263.76 μg kg⁻¹. Ampicillin also showed the highest frequency of residues above the recommended maximum residue limits. Detected cephalosporins were below 100 μg kg⁻¹ and showed their highest residue concentrations in broiler tissue samples. Calculated daily intake (CDI) and the hazard quotients (HQ) were used to assess human health risks. The CDI of ampicillin in broilers' breast muscles exceeded the Acceptable Daily Intake (ADI) and posed a medium risk (1 < HQ < 5) to adults. Meanwhile, the levels of ampicillin in both the thigh and breast muscles of broilers and ex-layer breast muscles exceeded the ADI for children indicating medium (1< HQ < 5) to high health risk (HQ > 5) to the youngsters. The study underscores the need for the continuous monitoring of antibiotics in chicken meat and addresses significant knowledge gaps on exposure levels and risks. This is valuable for policymaking to ensure food safety.