Ecotoxicity assessment and detection of antimicrobial compounds in urban environments and AMR hotspots

This study found widespread antibiotic contamination in surface water, groundwater, and wastewater effluents in Bengaluru and Mysuru, India. Five common antibiotics—erythromycin, amoxicillin, ciprofloxacin, sulfamethoxazole, and trimethoprim—were detected, with ciprofloxacin and sulfamethoxazole present at nearly all 28 sampling sites, reaching concentrations up to 20.19 µg/L. Risk analysis showed high ecological threat levels for sulfamethoxazole, amoxicillin, and ciprofloxacin at most sites, with many locations showing combined high-risk exposure to multiple drugs. The low PNEC ENV/MIC ratios indicated a strong potential for antimicrobial resistance development. Overall, the results identify critical pollution hotspots and underline the urgent need for improved wastewater treatment, stricter pollution controls, and ongoing environmental monitoring.