Fate of Macrolide Antibiotics with Different Wastewater Treatment Technologies

Abstract

Graphical abstract This comprehensive study addressed the occurrence, seasonal changes, removal efficiencies, and environmental risk assessments of three macrolide antibiotics in five wastewater treatment plants (WWTPs) with conventional and different additional treatment processes. A 1-year monitoring study was conducted, and influents and effluents were collected from Guangzhou (GZ), Shenzhen (SZ), Tai Po (TP), Shatin (ST), and Stonecutters Island (SI) WWTPs. Solid phase extraction and HPLC-MS/MS were used for the pretreatment and determination. The detection limits for azithromycin (AZI), erythromycin (ERY), and roxithromycin (ROX) ranged from 0.80 to 2.13 ng/L for the influent and effluent water samples. AZI was the most abundant antibiotic found in the influents, with average concentrations ranging from 571 ng/L to 1046 ng/L at all the target WWTPs. The seasonal average AZI concentration was the highest in all five WWTPs with the concentration of 984 ng/L in autumn, 849 ng/L in winter, 741 ng/L in summer, and 533 ng/L in spring. The seasonal AZI removal rates in the WWTPs were similar, with an average removal rate above 63.3% from spring to winter. All the treatments in the five WWTPs showed removal abilities for AZI, ERY, and ROX, regardless of the three phase treatments, namely, the UV disinfection process and conventional or chemically enhanced process within the WWTPs. For ERY and ROX, the average total removal rates were significantly decreased in the spring among all five WWTPs, at 53.1% and 57.8%, respectively. The GZ and SZ WWTPs displayed better removal rates than the TP, ST, and SI WWTPs, because the activity underlying the modified A2/O process in the GZ and SZ WWTPs has important effects on the antibiotic removal because the bacteria could produce compact granules and make the antibiotics settle faster in the wastewater. The additional UV disinfection in the SZ WWTP improved the removal efficiencies of the target antibiotics; it enhanced the biodegradability of residual organic pollutants in the WWTP effluent. Moreover, the corresponding environmental risks have been assessed and are viewed as a necessary component of future research. Supplementary Information The online version contains supplementary material available at 10.1007/s11270-021-05053-y.

Global Distribution and Diversity of Prevalent Sewage Water Plasmidomes

“…A high percentage of antibiotics are not fully metabolized in humans, and macrolides have been detected in wastewater, although wastewater treatment plants lower their abundances ( 16 , 78 ). The prevalence of various antibiotics in aquatic environments has recently been reviewed ( 79 ).…”

“…In recent years, urban sewage has been used as a comparable matrix to successfully study the global occurrence of antimicrobial resistance, the virome, and human populations ( 13 – 15 ). AMR in sewage reflects both the selective pressure in the general environment from which the sewage runs off, and the selective pressure caused by the presence of ARGs in the sewage (e.g., the usage of macrolide antibiotics leads to the presence of macrolide antibiotics in the sewage water itself) ( 16 ). We recently applied long read sequencing to explore the occurrence and diversity of the small plasmidome in 24 globally obtained sewage samples and assembled 165,302 contigs (159,322 circular), of which 58,429 carried genes encoding plasmid-related proteins and 11,222 carried genes encoding virus-related or phage-related proteins ( 17 ).…”

Management of Macrolide Antibiotics (Erythromycin, Clarithromycin and Azithromycin) in the Environment: A Case Study of Environmental Pollution in Lithuania

“…In assessing the effluents of pharmaceutical residues to surface waters via wastewater treatment plants (WWTPs), a wastewater treatment efficiency of 78.6% for AZI, 53.3% for ERY and 54% for CLA was accepted. The average rates were estimated on the scientific research base of target antibiotics already performed at WWTPs [22,[29][30][31][32]. The target macrolide antibiotics part that was removed from the effluents is considered in sludge.…”

“…The removal (Rj), excretion (Ej) factors and predicted no-effect concentration (PNEC) values were obtained from the literature and reported in Table 4. [29,22,30,31,32]; 3 [19,43,44].…”

Global distribution and diversity of prevalent sewage water plasmidomes

“…It was recently indicated that methicillin resistance emerged in Staphylococcus aureus in hedgehogs as an adaptation to beta-lactam-producing dermatophyte 79 highlights the coevolution among microbes in natural habitats as important sources of AMR emergence. A high percentage of antibiotics are not fully metabolized in humans, and macrolides have been detected in wastewater 80,81 , though wastewater treatment plants lower their abundance 81,82 .…”