Global perspectives on residual antibiotics: environmental challenges and trends

Extensive and indiscriminate use of different classes of antibiotics in hospitals, animal husbandry, veterinary, and aquaculture practices release substantial amounts of residual antibiotics into the environment, posing a potential hazard to the public and environmental health. This review aims to scrutinize the fate and impact of residual antibiotics on the environment and public health using global data trends on antibiotic usage and consumption. We highlight how different sources contribute to the release of residual antibiotics in the environment and countries that have the highest level of sources-wise residual antibiotics contamination. The World Health Organisation (WHO) report also highlights the changes in global antibiotic consumption patterns from 2016 to 2021 and gives an estimation of the increase in antibiotic use in 2030. This review looks at the fate and impact of residual antibiotics on the environment using global data trends on antibiotic usage and consumption, providing information on their levels in different ecosystems across the globe. The global data trends on antibiotic release, associated environmental risk, role in the development of antimicrobial resistance (AMR) and in the transfer of resistant genes through horizontal gene transfer (HGT) have also been elaborated. It is observed that countries like Vietnam, India, Italy, Pakistan, and Spain report relatively high levels of metronidazole, ciprofloxacin, ofloxacin, and moxifloxacin contamination in hospital effluents compared to other reported regions in the world. We assess the environmental impact and the global trend of antibiotic consumption from collected data and discuss areas for future research, improvements, and policy interventions.