Determination of antibiotic residues in bovine milk by HPLC-DAD and assessment of human health risks in Northwestern Himalayan region, India

Antibiotic residues in milk affects economics of dairy industry and poses health risks to consumers. This study aimed to assess health risks associated with presence of antibiotics in 173 raw and pasteurized milk sampled from northwestern Himalayan state of India. The oxytetracycline and amoxicillin were quantitatively analyzed using validated HPLC-DAD. Methods were selective and linear (R-2 > 0.99) with decision limit and detection capability of 1.4 and 0.9 mu g/kg and 2.5 and 1.5 mu g/kg for oxytetracycline and amoxicillin, respectively. Recoveries ranged from 88-98% with relative standard deviation < 10%. Oxytetracycline and amoxicillin were detected in 8.1% and 1.2% samples, with 1.7% and 1.2% samples exceeding the tolerance limits, respectively. Health risk assessment revealed that estimated daily intakes of antibiotics through milk were lower than acceptable daily intakes (ADI). However, children might receive 9-21% of determined ADI through milk consumption only. Therefore, continuous, sub-therapeutic and long term exposures of antibiotics can pose health risk to consumers. Hence, current findings elucidate the need for vigilant monitoring of antibiotics accompanied by educational programs to farmers for adopting good husbandry practices and adherence to withdrawal periods to meet the expectations of food safety and safeguarding human health.

Automated summary

This study assessed the health risks associated with antibiotic residues in 173 raw and pasteurized milk samples from northwestern Himalayan state of India. While overall estimated daily intakes of antibiotics through milk were lower than acceptable levels, children might receive a higher percentage of the acceptable daily intake only through milk consumption. Continuous monitoring of antibiotics and educational programs for farmers are essential to ensure food safety and safeguard human health.