Abstract—This study evaluated the occurrence, removal
efficiency, and environmental risks of ten commonly used
antibiotics in two Municipal Wastewater Treatment Plants
(WWTPs) in Ho Chi Minh City, Vietnam, one of the most densely
populated urban areas in Southeast Asia. Fluoroquinolones were
the most frequently detected antibiotics in influent samples, with
concentrations reaching the μg/L range, followed by sulfonamides
and trimethoprim. In contrast, macrolides were detected at low or
undetectable levels in raw wastewater. Although overall antibiotic
concentrations were significantly reduced after treatment,
residual fluoroquinolones persisted in the effluent, and macrolide
concentrations unexpectedly increased. Ecological risk
assessment of receiving waters indicated moderate risks
associated with azithromycin, levofloxacin, and ciprofloxacin.
These findings underscore the limitations of conventional
treatment technologies in fully mitigating antibiotic pollution and
raise concerns about the potential for the propagation of
antimicrobial resistance and long-term ecological harm. Further
research is recommended to assess antibiotic residues in
dewatered sludge, which may serve as a persistent environmental
reservoir, particularly where sludge is reused or disposed of on
land.
Keywords—antibiotics, fluoroquinolones, macrolides,
wastewater treatment plants, risk assessment
Cite: Do Thi Thuy Quyen, Tran Thi Yen Nhi, and To Thi Hien, "Antibiotic Contamination in Wastewater Treatment Plants of a Highly Urbanized City in Vietnam: Occurrence, Removal, and Environmental Risks," International Journal of Environmental Science and Development vol. 17, no. 2, pp. 117-125, 2026.
Copyright © 2026 by the authors. This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited (CC BY 4.0).