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The present study aims to examine the in vitro antifungal susceptibility patterns of Candida species isolated from hospital wastewater, and the efficacy of widely used disinfectants (sodium hypochlorite and benzalkonium chloride) against planktonic and biofilm cells were assessed. Susceptibility testing demonstrated that the two azoles were more effective against C. albicans than non-albicans isolates. When we determine the efficiency of disinfectants against the planktonic cells, benzalkonium chloride did not show any activity in all the studied strains under tested conditions except C. albicans-1. However, sodium hypochlorite showed ≥ 4 log 10 killing in viable cells for different contact times. On the other hand, while 0.1% and 1% concentrations of benzalkonium chloride showed fungicidal activity against biofilm cells, sodium hypochlorite at 1% only demonstrated fungicidal activity. Those results showed that surface water is a possible transmission path for fungi in the investigated hospital region and may be a health risk, especially for the immunocompromised host.

In this study, a lab-scale anaerobic sequencing batch reactor (AnSBR) was used for the acidification of a pharmaceutical wastewater sourced from etodolac chemical synthesis tanks. The effects of the organic loading rate (OLR), and etodolac and sulfate concentrations on the acidification rate and microbial community in AnSBR were investigated at 35 °C with a hydraulic retention time (HRT) of 37 h, a pH of 5, and OLRs up to 5.2 kgCOD/m 3 ·day. The AnSBR accomplished a 60% acidification ratio and 50-60% etodolac removal at OLRs up to 2.6 kgCOD/m 3 ·day. However, at OLR = 3.9 kgCOD/m 3 ·day, acidification was not achieved due to sulfite inhibition; pre-ozonation was applied to overcome this sulfite inhibition. Although etodolac and COD removals were improved, the wastewater was not successfully acidified. Real-time polymerase chain reaction (Q-PCR) and fluorescent in situ hybridization (FISH) analyses revealed that acidification was inhibited by the dominance of sulfate reducing bacteria (SRB) over acidification bacteria in the AnSBR. However, increasing the OLR to 5.2 kgCOD/m 3 ·day led to toxicity stress in the SRB due to increased sulfite concentrations. Sulfate load fundamentally affected acidification process and microbial community composition. The presence of etodolac with concentration up to 56 mg/L did not have a significant effect on VFA production and the microbial community., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

The aim of this study was to investigate the effect of high-influent-concentration suspended solids (SS) on the cultivation, structure and long-term stability of aerobic granular sludge (AGS). Cultivation and long-term stability of AGS were monitored in two pilot-scale sequencing batch reactors fed with raw (R1) and settled (R2) domestic wastewater, representing high and medium SS content, respectively. The real domestic wastewater had high chemical oxygen demand (COD) content (1100 ± 270 mg COD L -1 ). Aerobic granular sludge was cultivated in 44 days (R1) and 25 days (R2) under the conditions of high settling velocity (18 m h -1 ) and high organic loading rate (OLR) (2.1-2.4 kg COD m 3 day). The AGS in both reactors had similar structural properties during long-term operation and remained structurally and functionally stable during the last five months of operation. Comparative evaluation of the results indicated that the high influent SS content of the real domestic wastewater had a positive influence on maintaining significantly lower SVI 30 and relatively lower effluent SS concentration. Moreover, a higher influent SS content resulted in smaller mature granules during the stable period. Microbial community analyses helped to understand the aerobic granular sludge structure and showed that the sludge retention time and OLR affected the granular sludge population. The high influent SS increased biomass detachment from the granular sludge surface and caused wash-out of some bacteria colonizing the exterior of the granular sludge., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

The aim of the study was to present first preliminary characterization of Turkish hospital wastewaters, their environmental risk, and a method for toxicity assessment. The hospital wastewater samples were collected from two of the largest medical faculty hospitals and a training and research hospital in Istanbul, Turkey. The samples from the selected hospitals were taken as grab samples on March 2014. Overall, 55 substances including pharmaceuticals and their metabolites, pesticides, and corrosion inhibitors were analyzed in all hospital wastewaters. Analysis of toxicity and the antibiotic resistance bacteria were investigated in addition to the chemical analysis in the wastewater of one hospital. Hazard quotients (HQs) and toxic units (TUs) were calculated as basis of the environmental risk assessment. Fourteen pharmaceuticals in hospital wastewater (HWW) were classified as "high risk" with HQ > 10. HQ HWW values higher than 100 were determined for five antibiotics and one analgesic, namely, ofloxacin, clarithromycin, ciprofloxacin, sulfapyridine, trimethoprim, and diclofenac. Ofloxacin with an HQ HWW of 9090 was observed to be the most hazardous compound. HQ and TU values of the wastewater treatment plant (WWTP) effluent dropped significantly due to dilution in the sewer. Further elimination by biological degradation or adsorption was observed only in some cases. However, the decreased HQ WWTPeffluent values do not the change environmental load significantly. Therefore, advanced treatment processes should be applied to remove the persistent compounds. In combination with the results on antibiotic resistance, we would prefer on-site treatment of hospital wastewater. Toxicological assessment was performed using cytotoxic and mutagenic screening tests. The results of the Ames assay showed that the native hospital wastewaters had strongly mutagenic activity with a ≤10-fold increase relative to negative controls. The mutagenic potentials of the samples were generally concentration and metabolic activation dependent. Multiple antibiotic resistances were demonstrated with the tested isolates to ciprofloxacin, trimethoprim, and ceftazidime. This study demonstrates that the hospital wastewaters in Istanbul exhibit strong environmental and toxicological risks, as well as high multiple drug resistance to commonly used antibiotics.

In this study, the effects of organic loading rate (OLR) and the addition of powdered activated carbon (PAC) on the performance and membrane fouling of MBR were conducted to treat real pharmaceutical process wastewater. Over 145 days of operation, the MBR system was operated at OLRs ranging from 1 to 2 kg COD m(-3) day(-1) without sludge wasting. The addition of PAC provided an improvement in the flux, despite an increase in the OLR:PAC ratio. The results demonstrated that the hybrid PAC-MBR system maintained a reduced amount of membrane fouling and steadily increased the removal performance of etodolac. PAC addition reduced the deposition of extracellular polymeric substance and organic matter on the membrane surface and resulted an increase in COD removal even at higher OLRs with low PAC addition. Membrane fouling mechanisms were investigated using combined adsorption fouling models. Modified fouling index values and normalized mass transfer coefficient values indicated that predominant fouling mechanism was cake adsorption.