RESUMEN
In recent years especially during COVID-19, the increased usage of antiviral drugs has led to increased interest in monitoring their presence in wastewater worldwide. In this study, it was examined the occurrence, fate and environmental risks of favipiravir which is used for COVID-19 treatment in two wastewater treatment plants (WWTPs) with different treatment processes in Istanbul, Turkey. Favipiravir was measured in WWTPs influent samples, effluent samples and sludge samples with maximum concentrations of 97 µg/L, 64.11 µg/L and 182.47 µg/g, respectively. Favipiravir had removal efficiency below 55 % for both WWTPs. Mass balance analysis showed that favipiravir removal in WWTPs mainly attributed to biodegradation/biotransformation. Statistical analysis revealed a significant correlation between favipiravir concentration and COVID-19 incidence in Istanbul. The microbial distribution analysis indicated that comparison of collected COVID-19 pandemic sludge and post-pandemic period sludge samples, a noteworthy reduction in the Chloroflexi and Actinobacteriota phyla at the phylum level was observed. Environmental risk assessment using risk quotients ranged from 168 to 704, indicating that the presence of this antiviral drug posed significant ecological risks to aquatic organisms. The study concluded that WWTPs were releasing antiviral drugs into the environment, thereby posing risks to both the aquatic ecosystem and public health. The results of this study demonstrate the persistence of favipiravir in WWTPs and offer crucial supporting data for further research into the advancement of wastewater treatment technology. Also, this study shows wastewater based monitoring is supplementary and early warning system for determining the occurrence of antiviral drugs.
Asunto(s)
Amidas , Antivirales , COVID-19 , Pirazinas , Aguas Residuales , Contaminantes Químicos del Agua , Pirazinas/análisis , Amidas/análisis , Contaminantes Químicos del Agua/análisis , COVID-19/epidemiología , Antivirales/análisis , Eliminación de Residuos Líquidos , Medición de Riesgo , Turquía , Monitoreo del Ambiente , SARS-CoV-2 , Tratamiento Farmacológico de COVID-19RESUMEN
This study aimed to address the gap in understanding how the microbial community present within quorum quenching-membrane bioreactor (QQ-MBRs) changes during the operations by investigating the behavior of two different types of QQ bacteria, Bacillus sp. T5 and Delftia sp. T6. The anti-biofouling effects of T5 and T6 in the QQ-MBR were 85% and 76%, respectively. According to the Illumina HiSeq results, when the QQ-MBR was operated with Gram-positive bacteria, T5, in the mixed liquor a reduction was observed in Gram-positive bacteria and Gram-negative bacteria population increased. In contrast, when the QQ-MBR was operated with Gram-negative bacteria, T6, Gram-negative bacteria population reduced and an increase in Gram-positive bacteria observed. As such, the outputs of the Illumina analysis revealed that use of Gram-negative QQ bacteria in the reactor induced a Gram-positive microbial community and vice versa. This indicates that a close interaction occurs between indigenous Gram-negative and positive bacterial phyla, and Bacillus sp. T5/Delftia sp. T6 is fundamental to the performance of MBRs. This is the first study demonstrating such a relationship and assistance selecting QQ bacteria/strategy in an effective way.