Bioactivation of Quinolines in a Recombinant Estrogen Receptor Transactivation Assay Is Catalyzed by N-Methyltransferases.

Hydroxylation of polyaromatic compounds through cytochromes P450 (CYPs) is known to result in potentially estrogenic transformation products. Recently, there has been an increasing awareness of the importance of alternative pathways such as aldehyde oxidases (AOX) or N-methyltransferases (NMT) in bioactivation of small molecules, particularly N-heterocycles. Therefore, this study investigated the biotransformation and activity of methylated quinolines, a class of environmentally relevant N-heterocycles that are no native ligands of the estrogen receptor (ER), in the estrogen-responsive cell line ERα CALUX.

Systematic evaluation of a dynamic sewer process model for prediction of odor formation and mitigation in large-scale pressurized sewers in Hong Kong.

To evaluate and mitigate odor formation and emission in sewers, several sewer models have been developed. Although these models can predict the immediate effects of chemical dosing on odor emission control, the long-term effects due to the variation of biofilm dynamics were generally underestimated. Therefore, in this study, we developed a dynamic model to simulate sewer processes initiated by sewer.

Nutrients recovery from treated secondary mainstream in an urban wastewater treatment plant: A financial assessment case study.

This study presents the financial assessment for implementing an ammonium and phosphate simultaneous recovery process based on the use of calcium activated synthetic zeolites in a large urban Waste Water Treatment Plant (WWTP) located in the Metropolitan Area of Barcelona. A calcium activated synthetic zeolites was selected, after a benchmarking analysis, as it reported capability for simultaneously recover ammonium and phosphate by a combined mechanism of ion exchange for ammonium and formation of insoluble mineral phase for phosphate. The loaded sorbent, rich in ammonium and phosphate, can be used as slow-release fertilizer.

Aerobic metabolic trichloroethene biodegradation under field-relevant conditions.

Chloroethenes belong to the most widely distributed groundwater contaminants. Since 2014, it has been known that trichloroethene (TCE) can be degraded aerobically and metabolically as growth substrate by a mixed bacterial enrichment culture (named SF culture). In this study, the degradation capabilities under a range of field-relevant conditions were investigated in fixed-bed reactors as well as in batch experiments.

Elucidating the effects of starvation and reactivation on anaerobic sulfidogenic granular sludge: Reactor performance and granular sludge transformation.

In biological wastewater treatment, the bacteria starvation always challenges the stability of system operation. Yet, the effects of starvation and possibility of reactivation are less understood for anaerobic sulfidogenic system. Sulfidogenic systems use sulfate as electron acceptor for organic chemical oxygen demand (COD) degradation, so it will encounter two kind of starvations: (i) complete stoppage of wastewater flow (named complete food starvation) and (ii) remaining organic COD but with very low level sulfate in the influent (named sulfate starvation).

Recent advances in dissimilatory sulfate reduction: From metabolic study to application.

Sulfate-reducing bacteria (SRB) are a group of diverse anaerobic microorganisms omnipresent in natural habitats and engineered environments that use sulfur compounds as the electron acceptor for energy metabolism. Dissimilatory sulfate reduction (DSR)-based techniques mediated by SRB have been utilized in many sulfate-containing wastewater treatment systems worldwide, particularly for acid mine drainage, groundwater, sewage and industrial wastewater remediation. However, DSR processes are often operated suboptimally and disturbances are common in practical application.

Economical lipid production from Trichosporon oleaginosus via dissolved oxygen adjustment and crude glycerol addition.

The effect of dissolved oxygen concentration on lipid accumulation in Trichosporon oleaginosus has been investigated. The experiment was performed in 15 L fermenters. The dissolved oxygen concentration varied by adjusting the agitation and aeration.

Food waste treatment by anaerobic co-digestion with saline sludge and its implications for energy recovery in Hong Kong.

Potential of methane production by co-digestion of food waste with saline sludge produced from sewage receiving seawater toilet flushing was investigated to determine its suitability for food waste management in Hong Kong by making use of excess design capacity of sludge digesters. High salinity of saline sludge (12.8 mS/cm) affected degradation of organic compounds resulting in an increase in sCOD by 135% as compared to an increase by 283% in treatments with non-saline sludge (4.

Sludge flotation, its causes and control in granular sludge upflow reactors.

Sludge flotation is a commonly reported and long-standing issue hindering not only the widespread implementation of upflow anaerobic sludge bed (UASB)-type bioreactors in wastewater treatment but also the development of novel anaerobic/anoxic treatment processes such as anammox, partial denitrification, and biological sulfate reduction. This review attempts to address the instability of UASB-type bioreactors due to sludge flotation. Possible causes of sludge flotation are classified into intrinsic and extrinsic ones.

Time series study of weather, water quality, and acute gastroenteritis at Water Safety Plan implementation sites in France and Spain.

Water Safety Plans (WSPs), recommended by the World Health Organization since 2004, can help drinking water suppliers to proactively identify potential risks and implement preventive barriers that improve safety. Few studies have investigated long-term impacts of WSPs, such as changes in drinking water quality or public health; however, some evidence from high-income countries associates WSP implementation with a reduction in diarrheal disease. To validate the previously observed linkages between WSPs and health outcomes, this time series study examined site-specific relationships between water-related exposures and acute gastroenteritis rates at three locations in France and Spain, including the role of WSP status.

Quantitative characterization and analysis of granule transformations: Role of intermittent gas sparging in a super high-rate anaerobic system.

Knowledge of leveraging biomass characteristics is essential for achieving a microbial community with a desired structure to optimize anaerobic bioreactor performance. This study investigates the successive granule transformations in a high-rate anaerobic system with intermittent gas sparging and sequential increases in organic loading rates (OLRs), by establishing the correlations between the granule microstructures and reactor operating parameters. Over the course of a 196-day lab-scale trial, the granules were visualized in various stages using scanning electron microscopy, and digital image processing was applied for further quantifying their surface properties.

Effects of metoprolol on aquatic invertebrates in artificial indoor streams.

Aquatic organisms are impacted by various biotic and abiotic stressors such as current, inter- and intraspecific competition for food resources and habitat, neobiota as well as an increasing number of chemicals. The latter also include pharmaceuticals, which are increasingly being detected in surface waters due to their growing use. The aim of our study was to determine effect data for metoprolol as a model compound for beta-blockers under an environmentally realistic exposure scenario on aquatic invertebrates inhabiting lotic environments.

Simultaneous ammonium and phosphate recovery and stabilization from urban sewage sludge anaerobic digestates using reactive sorbents.

The use of low-cost inorganic sorbents as a new sustainable strategy to enhance the valorization of nutrients (N-P-K), from the urban water cycle (e.g., side streams from sewage sludge anaerobic digestion), in agriculture applications is presented.

Application of a moving-bed biofilm reactor for sulfur-oxidizing autotrophic denitrification.

Sulfur-oxidizing autotrophic denitrification (SO-AD) was investigated in a laboratory-scale moving-bed biofilm reactor (MBBR) at a sewage temperature of 22 °C. A synthetic wastewater with nitrate, sulfide and thiosulfate was fed into the MBBR. After 20 days' acclimation, the reduced sulfur compounds were completely oxidized and nitrogen removal efficiency achieved up to 82%.

Characterization of a new continuous gas-mixing sulfidogenic anaerobic bioreactor: Hydrodynamics and sludge granulation.

Continuous gas recirculation (CGR) was demonstrated in this study to be an effective method to mitigate the persistent problem of sludge flotation in high-rate sulfate-reducing upflow sludge bed (SRUSB) reactors that do not produce much gas. The effects of hydraulic- and CGR-mixing on the mixing regime of the SRUSB reactors were investigated over a period of 45 d at the average shear rates of 0.9, 1.

Development of biochemical sulfide potential (BSP) test for sulfidogenic biotechnology application.

The determination of organics biodegradability and corresponding biodegradation kinetics provides valuable information on the optimal design and operation of anaerobic biotechnology especially for sulfidogenesis. This study proposes a deterministic method, i.e.

Understanding the effects of bulk mixing on the determination of the affinity index: consequences for process operation and design.

The main objective of this study is to demonstrate the importance of mixing conditions as a source of inconsistencies between half-saturation indices in comparable systems (e.g. conventional activated sludge, membrane bioreactor) when operated at different conditions or different scales.

Elucidating the stimulatory and inhibitory effects of dissolved sulfide on sulfur-oxidizing bacteria (SOB) driven autotrophic denitrification.

Autotrophic denitrification has been widely studied for odor mitigation, corrosion control and nitrogen removal in recent years. This paper examines the response of sulfur-oxidizing bacteria (SOB) driven autotrophic denitrification under short-term stress of dissolved sulfide. A series of batch tests were conducted to investigate the effect of different sulfide concentrations (0-1600 mg-total dissolved sulfide (TDS)/L) on autotrophic denitrification and sulfide oxidation by SOB-enriched sludge.

Realizing high-rate sulfur reduction under sulfate-rich conditions in a biological sulfide production system to treat metal-laden wastewater deficient in organic matter.

Biological sulfur reduction can theoretically produce sufficient sulfide to effectively remove and recover heavy metals in the treatment of organics-deficient sulfate-rich metal-laden wastewater such as acid mine drainage and metallurgic wastewater, using 75% less organics than biological sulfate reduction. However, it is still unknown whether sulfur reduction can indeed compete with sulfate reduction, particularly under high-strength sulfate conditions. The aim of this study was to investigate the long-term feasibility of biological sulfur reduction under high sulfate conditions in a lab-scale sulfur-reducing biological sulfide production (BSP) system with sublimed sulfur added.

Self-accelerating sulfur reduction via polysulfide to realize a high-rate sulfidogenic reactor for wastewater treatment.

Sulfur reduction is a promising alternative to sulfate reduction as it can generate sulfide at a low cost for the precipitation of heavy metals or autotrophic denitrification in wastewater treatment. However, the extremely low water solubility of elemental sulfur limits its bioavailability and results in a low sulfur-reduction rate. Polysulfide, which is naturally generated through reactions between sulfur and sulfide, can enhance the bioavailability of sulfur and thus contribute to high-rate sulfur reduction.

The characteristics of household food waste in Hong Kong and their implications for sewage quality and energy recovery.

Food waste (FW) is a worldwide environmental issue due to its huge production amount. FW separation from municipal solid waste followed by different treatment strategies has been widely accepted. Food waste disposer (FWD) is a promising approach to separate and collect household food waste (HFW), which has been widely applied in many countries.

Does wastewater treatment plant upgrading with activated carbon result in an improvement of fish health?

In the present study, the efficiency of a wastewater treatment plant (WWTP) upgraded with a powdered activated carbon unit for the reduction of micropollutants and the related advantages for fish health have been analyzed by means of different biomarkers, i.e. histopathological investigations, analyses of glycogen content and stress proteins, as well as by chemical analyses in different matrices.

A Phosphorous Flow Analysis in Spain.

Phosphorus (P) is a vital macronutrient required to improve the agricultural yields but its excessive use as a fertilizer has resulted in pollution of water bodies leading to eutrophication. With no reserves of phosphorus source in Spain, increased dependence on phosphorus in agriculture have not only increased dependence on imports but also has raised concerns on its future availability as a resource. A Phosphorous Flow Analysis (PFA) was conducted for Spain for the year 2012 focusing on the food production and consumption systems.

Valorisation of N and P from waste water by using natural reactive hybrid sorbents: Nutrients (N,P,K) release evaluation in amended soils by dynamic experiments.

The removal of nutrients (nitrogen (N), phosphorous (P)) from waste water has become a resource recovery option in recent regulations worldwide, as observed in the European Union. Although both of these nutrients could be recovered from the sludge line, >70-75% of the N and P is discharged into the water line. Efforts to improve the nutrient recovery ratios have focused on developing low-cost technologies that use sorption processes.

The role of sulfate in aerobic granular sludge process for emerging sulfate-laden wastewater treatment.

Sulfate-rich wastewaters pose a major threat to mainstream wastewater treatment due to the unpreventable production of sulfide and associated shift in functional bacteria. Aerobic granular sludge could mitigate these challenges in view of its high tolerance and resilience against changes in various environmental conditions. This study aims to confirm the feasibility of aerobic granular sludge in the treatment of sulfate containing wastewater, investigate the impact of sulfate on nutrient removal and granulation, and reveal metabolic relationships in the above processes.