Characteristics, fate, and risk of antibiotics in on-site hospital wastewater treatment plants of three types of hospital

Abstract

Abstract Antibiotics have received increasing attention because of their ecological impact and risk to human health. Hospitals are a major source of antibiotic pollution. This study investigated the emission characteristics, removal efficiency, and environmental risk of antibiotics in wastewater from on-site treatment plants in three different types of hospitals: a general hospital (GP), a traditional Chinese medicine hospital (TCM), and a cardiac hospital (CP) in Beijing, China. The total antibiotic concentration of TCM effluent was 4996.7 ± 692.4 ng/L, higher than GP effluent (3483.0 ± 328.4 ng/L) and CP effluent (2627.2 ± 267.1 ng/L). TCM had the highest antibiotic concentration in influents (7566.9 ± 495.3 ng/L) and effluents, while the GP influent contained the greatest variety of antibiotics. Macrolides (MAs) and quinolones (QUs) were the main antibiotics in the studied effluents, with the sum of the two contributing to 75.2%, 63.1%, and 57.7% of the GP, TCM, and CP effluents, respectively. Clarithromycin (CLA), azithromycin (AZM), ofloxacin (OFL), and ciprofloxacin (CIP) were the main antibiotics detected in both the influents and effluents in all three types of hospitals. The overall removal efficiencies of the three hospitals were low at 30.8%, 34.0%, and 42.2% for GP, TCM, and CP, respectively. The removal efficiencies of different antibiotics in the treatment facilities of the three hospitals were different. High RQ of roxithromycin (ROX), a regional antibiotic detected only in China, OFL, and erythromycin (ERY) were found in all treatment facilities. In MBR treatment systems, the micro-environment of bacteria is exposed to high environmental risk from antibiotics, potentially inhibiting its removal efficiency on other pollutants. In this investigation, a glimpse of the antibiotic emission characteristics in the hospital wastewater of different types of hospitals in Beijing, China, was given, which will benefit the formulation of new medical guidelines, development of treatment technology, and revision of emission standards.