The behavior of antibacterial triclosan, insect-repellent diethyltoluamide (DEET), anticonvulsant carbamazepine, and antipruritic crotamiton was investigated at two sewage treatment plants (STPs) to clarify their complete mass balance. Twenty-four-hour flow-proportional composite samples were collected from the influent and effluent of primary and final sedimentation tanks, a biofiltration tank and disinfection tanks. Sludge samples (i.e., activated and excess sludge) and samples of the return flow from the sludge treatment process were collected in the same manner. The analytes in both the dissolved and particulate phases were individually determined by a gas chromatograph equipped with mass spectrometer. Triclosan was dominantly detected in the particulate phase especially in the early stage of treatment (up to 83%) and was efficiently removed (over 90%) in STPs, mainly by sorption to sewage sludge. Limited removal was observed for DEET (55±24%), while no significant removal was demonstrated for crotamiton or carbamazepine. The solid-water distribution coefficients (Kd, n=4) for triclosan (log Kd: 3.7–5.1), DEET (1.3–1.9) and crotamiton (1.1–1.6) in the sludge samples are also determined in this study. These findings indicate the limitations of current sewage treatment techniques for the removal of these water-soluble drugs (i.e. DEET, carbamazepine, and crotamiton).
This study investigated the fate of estrogenic substances in an urban river receiving discharge from wastewater treatment plants (WTPs) by flux calculation, focusing on the middle reaches of the Tama River in Tokyo, which is one of the most urbanized rivers in Japan. The level of estrogenic activity flux was almost negligibly small at the upstream station. The level was considerably raised after inflows from the WTPs and then the level declined in the lower reaches of the river. When contributions of estrogenic substances to estrogenic activity were estimated, estrone (E1) was the primary contributor to the total estrogenic activity in all the sampling stations, followed by estradiol (E2). The contribution of nonylphenol to estrogenic activity was small. The E1 and E2 accounted for approximately 90% or more of estrogenic activity in the Tama River. As for the total fluxes of the estrogenic substances in the study area in the Tama River, the proportion of flux associated with WTP discharge was approximately 100% of the total fluxes, and the effects of the tributaries flowing into the river were almost negligible. When the reduction ratios of estrogenic activity were calculated by the flux, the ratios were found to increase toward the lower reaches of the river. Similar changes were observed for E1. Meanwhile, the change of reduction ratios for E2 was different from that observed for estrogenic activity.
In recent years, antibiotics resident in sewage and in the water environment have become an emerging public concern in many developed countries. However, limited knowledge is available on the occurrence of antibiotics in sewage and discharge from wastewater treatment plants (WWTPs) in Japan. Moreover, little is known on the significance of their occurrence in the water environment from the viewpoints of biological adverse effects. The objectives of this research were, therefore, to determine the occurrence of selected antibiotics, namely levofloxacin (LVFX) and clarithromycin (CAM). That are commonly used in Japan, in discharge from WWTPs and then to evaluate their possible effects on algal growth. Therefore, we developed a novel analysis method for LVFX and CAM in wastewater by LC/MS/MS whose detection limits and recovery ratios are 2-3ng·l-1 and 53-87%, respectively. We also conducted algal growth inhibition tests using Pseudokirchneriella subcapitata, and results showed that the EC50s of LVFX and CAM are 1200μg·l-1 and 11μg·l-1, LOECs are 630μg·l-1 and 6.3μg·l-1, and NOECs are 310μg·l-1 and 3.1μg·l-1, respectively, LVFX and CAM concentrations in secondary effluent of five WWTPs that use the activated sludge process ranged from 152-323ng·l-1 and 303-567ng·l-1, respectively, which indicates that the PEC/PNEC ratio of LVFX is less than one but that of CAM exceeds two at the maximum secondary effluents if a safety factor of ten is considered. This suggests a possibility of algal growth inhibition due to CAM in WWTP discharge in the case of insufficient dilution of the receiving waters.
Abstract Wastewater surveillance is an effective tool for monitoring community spread of covid-19 and other diseases. Quantitative PCR (qPCR) analysis for wastewater surveillance is more susceptible than binary PCR analysis for clinical surveillance to mutations in target genome regions. The SARS-CoV-2 concentrations in wastewater estimated by N1 and N2 qPCR assays started to diverge around July 2022 in data from different sampling sites, analytical methods, and analytical laboratories in Japan. On the basis of clinical genomic surveillance data and experimental data, we demonstrate that the divergence is due to two mutations in the N1 probe region, which can cause underestimation of viral concentrations. We further show that this inaccuracy can be alleviated if the qPCR data are analyzed with the second derivative method or the Cy0 method instead of the crossing point method.
Degradation of Free Estrogens and their Conjugates in Wastewater Treatment ProcessThis paper describes degradation characteristics of free estrogens and their conjugates in simulated membrane bioreactor (MBR). Hydraulic retention time (HRT) of aerobic section was set at 8 hours and aerobic solids retention time (A-SRT) was set at 60 days. Target substances were 17β-estradiol (E2), estrone (E1), 17α-ethynylestradiol (EE2), estriol (E3), estrone-3-sulfate (E1-S),...Author(s)Yuji OkayasuKoya KomoriMakoto YasojimaYutaka SuzukiSourceProceedings of the Water Environment FederationSubjectSession 5: Occurrence and Treatment of Emerging ContaminantsDocument typeConference PaperPublisherWater Environment FederationPrint publication date Jan, 2005ISSN1938-6478SICI1938-6478(20050101)2005:5L.291;1-DOI10.2175/193864705783977934Volume / Issue2005 / 5Content sourceTechnology ConferenceFirst / last page(s)291 - 297Copyright2005Word count127
Nonylphenol (NP) is known to be a byproduct of nonylphenol ethoxylates (NPnEO) which are used as detergents in industry. It is important that not only NP but also NPnEO and their related substances are analysed when behaviour of NP in the wastewater treatment process is surveyed. NPnEO are biodegraded to shorter ethoxylate (EO) chain NPnEO or nonylphenol carboxylates (NPnEC) under aerobic conditions, and then biodegraded to NP under anaerobic conditions. NP is one of the suspected endocrine disruptors (ED). Moreover, shorter EO chain NPnEO has greater toxicity than longer EO chain NPnEO. We conducted a field survey of NP and its related substances in 20 wastewater treatment plants (WWTP). The concentrations (median) of NP and its related substances in the WWTPs' influent ranged from 0.1 to 8.3 microg/L, showing NP concentration as the same level as those previously reported. The reduction of the long EO chain NPnEO in the WWTPs was almost complete, while the removal efficiency for the short EO chain NPnEO was less significant than the long EO chain NPnEO, suggesting that the degradation rate of the short EO chain NPnEO was lower than that of the long EO chain NPnEO in the wastewater treatment