Rising Tide Of Antibiotics And Antibiotic Resistance: Insights From Urban Environments And Hospital Effluents In Accra, Ghana

Abstract

Antibiotic overuse has led to the contamination of aquatic ecosystems and the disruption of bacterial communities. However, in resource- limited settings, few studies have examined environmentally driven antibiotic resistance, leaving significant gaps in understanding its environmental contribution. This study assessed the occurrence of seven antibiotics in surface waters and hospital and wastewater treat ment plant effluents and investigated the antibiotic resistance patterns and genomic profiles of Escherichia coli isolates from these environments. Water samples were processed using solid-phase extraction and analysed using high-performance liquid chromatography and photodiode array detection. The highest antibiotic concentrations detected in water samples were chloramphenicol (0.992 and 0.675 mg/L), followed by ampicillin (0.531 mg/L) and cefuroxime (0.127 mg/L). Hospital effluents contained trimethoprim (0.332 mg/L), ampi cillin (0.240 mg/L), amoxicillin (0.179–0.238 mg/L), and cefuroxime (0.127 mg/L). Ecological risk assessment indicated that trimethoprim and chloramphenicol may pose significant risks to aquatic organisms. E. coli isolates frequently exhibited resistance to ampicillin (63%), sulfa methoxazole–trimethoprim (42%), meropenem (47%), and azithromycin (46%). These findings suggest that antibiotic contamination in aquatic environments may contribute to the development, persistence, and spread of antibiotic resistance, posing ecological and public health risks. This study highlights the need for regular monitoring of antibiotic residues and resistance genes within a One Health framework.