Gregory V Korshin

University of Washington | UW · Department of Civil and Environmental Engineering

This study explores the GAC adsorption of perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS), that stands out as the most frequently produced and detected compounds belonging to the class of poly- and perfluoroalkyl substances (PFAS). Experiments were performed on three distinct wastewaters (WW-1, WW-2, WW-3) employing rapid smal...

The presence in seawater of low-molecular-weight polyethylene (PE) and polydimethylsiloxane (PDMS), synthetic polymers with high chemical resistance, has been demonstrated in this study for the first time by developing a novel methodology for their recovery and quantification from surface seawater. These synthetic polymer debris (SPD) with very low...

Greenhouse gases (GHGs) emissions due to increasing energy demand have raised the need to identify effective solutions to produce clean and renewable energy. Biotechnologies are an effective platform to attain green transition objectives, especially when synergically integrated to promote health and environmental protection. In this context, micro...

The next generation of the self-forming dynamic membrane, referred to in this study as the “Living Membrane (LM)”, is a new patented technology based on an encapsulated biological layer that self-forms on a designed coarse-pore size support material during wastewater treatment and acts as a natural membrane filter. Integrating electrochemical proce...

N-Nitrosodimethylamine (NDMA) is a disinfection by-product and a probable human carcinogen formed during water treatment processes. While its generation in engineered systems has been extensively explored, its formation in natural environments is inadequately understood. This study demonstrates that compounds with dimethylamine (DMA) functionality...

Bromide (Br–) and nitrite (NO2–) can be transformed to brominated and nitrophenolic byproducts, respectively, in sulfate radical (SO4·–)-based oxidation processes, which has raised growing concern. In the present work, we examined the byproducts in the heat-activated persulfate oxidation system with the copresence of Br– and NO2–, finding that Br–...

Natural organic matter (NOM) is critical for the biogeochemical cycles of energy and many elements in terrestrial and aquatic ecosystems, and protonation-active functional groups in NOM molecules, notably carboxylic and phenolic groups often mediate these critical environmental functions. Molecular heterogeneity, polydispersity and dynamic behavior...

Hydrogen sulphide (H2S) removal from biogas is of high relevance as it damages combustion engines used for heat and power generation and causes adverse public health and environmental effects. Biological processes have been reported as a cost-effective and promising approach to desulfurize biogas. This review presents a detailed description of the...

This study delves into the microbial community complexity and its role in self-forming dynamic membrane (SFDM) systems, designed to remove nutrients and pollutants from wastewater, by means of the analysis of Next-Generation Sequencing (NGS) data. In these systems, microorganisms are naturally incorporated into the SFDM layer, which acts as a biolo...

Electrochemical oxidation (EO) is an attractive option for treatment of dissolved organic matter (DOM) in landfill leachate but concerns remain over the energy efficiency and formation of oxidation byproducts ClO3- and ClO4-. In this study, EO treatment of landfill leachates was carried out using representative active and nonactive anode materials,...

The current ex situ analytical methods to determine concentrations of dissolved organic carbon (DOC) are largely inadequate to form a dynamic understanding of the global carbon cycling, especially given the urgent need to understand how the oceans are responding to increasing concentrations of atmospheric CO2 and climate change. Here we establish a...

Tetrabromobisphenol S (TBBPS) is a brominated flame retardant and a contaminant of emerging concern. Several studies found that sulfate radical (SO4•–) oxidation is effective to degrade TBBPS. Here, we demonstrate that the presence of nitrite (NO2–) at environmentally relevant levels causes dramatic changes in the kinetics and pathways of TBBPS deg...

This work provides a brief overview of the application of Sewage Sludge-Derived Biochar (SSBC) for the removal of micropollutants from aqueous solutions and wastewater. A particular emphasis is placed on the adsorption efficiency of SSBC regarding the Priority Substances defined under the scope of the EU Water Framework Directive

The XANES/EXAFS data and quantum chemical simulations presented in this study demonstrate several features of the chemistry of arsenic compounds found in the condensates and solids generated in landfill gas (LFG) processing carried out for renewable natural gas (RNG) production. The XANES data show the decrease in the position of the absorption edg...

Antibiotics are ubiquitous in wastewater and surface water and their presence is of grave concern. Chlorination, an important disinfection process used in wastewater treatment plants and waterworks, causes antibiotics to be degraded. However, interactions of antibiotics with chlorine result in the generation of multiple transformation products (TPs...

An advanced concept of aerobic membrane bioreactors (MBRs) for highly efficient wastewater treatment has been disclosed by introduction of an electro and encapsulated self-forming dynamic biomembrane (e-ESFDM). The biological filtering membrane is intercalated between two woven polyester fabrics as supports that assist the formation and protect the...

This study compared effects of conventional ozonation and electrochemical oxidation (EO) on the formation of aldehydes and aliphatic carboxylic acids produced via the oxidation of natural organic matter (NOM) present in a low-mineralized surface water with a relatively low NOM concentration. Conventional ozonation and EO were effective in degrading...

Wastewater-based epidemiology (WBE) is a powerful tool that has the potential to reveal the extent of an ongoing disease outbreak or to predict an emerging one. Recent studies have shown that SARS-CoV-2 concentration in wastewater may be correlated with the number of COVID-19 cases in the corresponding population. Most of the recent studies and app...

Recent studies found that both nitrite (NO 2 −) and ammonium (NH 4 +) lead to nitrophenolic byproducts in SO 4 •− oxidation processes, during which NO 2 • generated through the oxidation of the inorganic nitrogen by SO 4 •− is the key nitrating agent. This study demonstrates that the formation of phenoxy radicals to which NO 2 • can be incorporated...

Membrane bioreactors (MBRs) for wastewater treatment are being extensively studied and optimized to achieve the following: (a) higher pollutant removal efficiency, (b) better fouling control, (c) lower energy consumption, or (d) higher energy production in MBRs. These efforts have led to the development of a number of alternative advanced configura...

A hierarchically ordered macroporous RuO2 electrode (HOM-RuO2) was fabricated to enhance in situ active chlorine production in an electrochemical system intended for treatment of pharmaceutical active compounds (PhACs). The unique structure of HOM-RuO2 resulted in a decrease of the chlorine evolution potential, a large electro-active area available...

Methylated arsenic species are ubiquitous in the environment and resistant to removal by conventional treatment technologies. This study addressed this challenge based on the examination of the removal of dimethylarsinic acid (DMA) in a system that combines zerovalent iron (ZVI) and powdered activated carbon (PAC). The removal of DMA in the ZVI/PAC...

Chlorination is the most common disinfection technology used to treat wastewater effluent discharged into receiving aquatic environments. Effluent organic matter (EfOM) abundant in wastewater is a well-known photosensitizer and it greatly affects phototransformations of antibiotics in water. However, effects of chlorination on the characteristics a...

In this study, we have identified 6-L-biopterins and their glucosides as candidate structures for the consistently occurring algae-derived humic-like fluorophores (Em 440−460 nm) using a combination of fluorescence excitation-emission matrixes, size exclusion chromatography with fluorescence detector and ultra-high performance liquid chromatography...

The binding between dissolved organic matter (DOM) and micro-pollutants (MPs) results in significant impacts on their migration, transformation and degradation. However, the role of the DOM/MP binding on their oxidative transformation remains poorly studied. The binding of MPs by DOM, in combination with DOM's roles as a photosensitizer and/or a co...

Exposure to ultrafine combustion aerosols such as particulate matter (PM) from residential woodburning, forest fires, cigarette smoke, and traffic emission have been linked to adverse health outcomes. Excitation-emission matrix (EEM) spectroscopy presents a sensitive and cost-effective alternative for analysis of PM organic fraction. However, as wi...

Concentrations of several toxic disinfection by-products (DBP), notably haloacetonitriles (e.g., trichloroacetonitrile, TCAN) and haloketones (e.g., di- and trichloropropanone, DCPN and TCPN, respectively) are affected by chlorination conditions and the inherent instability of these DBPs. In this study, effects of temperature, chlorine dose and rea...

Introduction Self-forming dynamic membrane (SFDM) technology has been gaining significant interest due to its potential advantages, notably lower capital and operational cost and easier fouling control, over conventional membranes used in membrane bioreactors. SFDM technology utilizes inexpensive support material integrated with a dynamic membrane...

Considerable attention has been recently given to possible transmission of SARS-CoV-2 via water media. This review addresses this issue and examines the fate of coronaviruses (CoVs) in water systems, with particular attention to the recently available information on the novel SARS-CoV-2. The methods for the determination of viable virus particle an...

The first case of Coronavirus Disease 2019 (COVID-19), which is caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), in Europe was officially confirmed in February 2020. On 11 March 2020, after thousands of deaths from this disease had been reported worldwide, the WHO changed their classification of COVID-19 from a public health...

In this study, the model compound esculetin that has functional groups typical for natural organic matter (NOM) was used to ascertain the nature of the characteristic bands in the differential UV-visible absorbance spectra (DAS) associated with the formation of metal-NOM complexes. The binding of ten different metal ions (Cu(II), Ni(II), Co(II), Fe...

This study compared effects of pH, ionic strength and complexation with Mg²⁺ on the chromophores and fluorophores of aquatic and terrestrial NOM exemplified by the standard isolates Suwannee River fulvic and humic acid (SRFA and SRHA) and Pahokee Peat fulvic and humic acids (PPFA and PPHA) provided by the International Humic Substance Society (IHSS...

This study examined effects of aquatic and soil natural organic matter (NOM) exemplified by standard Suwannee River fulvic acid (SRFA) and Pahokee Peat fulvic acid (PPFA), respectively, on the electrochemical (EC) reactivity and mass transfer properties of the cationic organic probe toluidine blue (TB) that forms complexes with NOM. EC measurements...

This paper presents an updated and comprehensive review on the different methods used for detection and quantification of viruses in wastewater treatment systems. The analysis of viability of viruses in wastewater and sludge is another thrust of this review. Recent studies have mostly focused on determining the abundance and diversity of viruses in...

This study compared chlorination-induced changes of the properties of natural organic matter (NOM) represented by standard humic substances and NOM present in pristine and anthropogenically-affect reservoirs, rivers, groundwater and seawater. The chlorination-induced changes of NOM properties were quantified using the differential absorbance spectr...

Analysis of particulate matter (PM) is important for the assessment of human exposures to potentially harmful agents, notably combustion-generated PM. Specifically, polycyclic aromatic hydrocarbons (PAHs) found in ultrafine PM have been linked to cardiovascular diseases and carcinogenic and mutagenic effects. In this study, we quantify the presence...

Time-resolved monitoring of bromate and other by-products formed into effluents treated with ozone or advanced oxidation processes in wastewater treatment plants (WWTPs) is time-consuming and expensive. This study examined whether concentrations of bromate formed in wastewater after ozonation in the presence of widely varying bromide levels (from c...

Roxithromycin (ROX) is a widely used macrolide antibiotic and its environmental fate and ecotoxicity have attracted considerable attention. In this study, the phototransformation kinetics and products of ROX under the irradiation of simulated sunlight were investigated. The ecotoxicity of ROX before and after phototransformation were also examined...

p>Exposure to combustion generated aerosols such as PM from residential woodburning, forest fires, cigarette smoke, and traffic emission have been linked to adverse health outcomes. It is important to assess the chemical composition of PM to examine personal exposure. Excitation-emission matrix (EEM) spectroscopy has been shown as a sensitive and c...

The release of potentially toxic metal ions from corrosion scales formed on pipe surfaces is of great concern for water quality in drinking water distribution systems (DWDS). This study examined the effects of alkalinity, chloride, and sulfate on metal release from corrosion scales sampled from a corroded iron pipe. Jar tests and recirculation pipe...

The presence of galvanized pipe in drinking water distribution systems is known to be associated with heavy metal release, especially after the aging of zinc coating. This study examined release of lead and other heavy metals (e.g., cadmium, chromium) from galvanized steel coupons with a low-lead zinc coating. Metal release data were obtained in 12...

In this study, size exclusion chromatography with an array of absorbance, fluorescence, organic nitrogen and organic carbon detectors was used for characterizing property and treatability of effluent organic matter (EfOM) from 12 wastewater treatment plants. According to their apparent molecular weight (AMW), EfOM fractions were assigned to biopoly...

This study examined the kinetics of the binding of Al(III) ions by natural organic matter (NOM) exemplified by Suwannee River humic acid (SRHA). This processes was studied for a 5-8 pH range and environmentally relevant concentrations of the system components. Al(III)-NOM interactions were quantified using differential absorbance spectra whose inte...

Analysis of particulate matter (PM) is important in assessing an individual’s exposure to potentially harmful particles, such as aeroallergens, toxins, and emissions from combustion sources. Polycyclic aromatic hydrocarbons (PAHs) are a widespread class of environmental chemical pollutant found in combustion-generated PM. They are associated with c...

Thermodynamic and kinetic aspects of the formation of trihalomethanes and haloacetic acids determined based on the quantum chemical (QC) simulations were compared in this study with the experimental data generated using the differential spectroscopy approach in chlorination and chloramination. The ratios of the slopes of the correlations between -D...

The inhalation of particulate matter (PM) is a significant health risk associated with reduced life expectancy due to increased cardio-pulmonary disease and exacerbation of respiratory diseases such as asthma and pneumonia. PM originates from natural and anthropogenic sources including combustion engines, cigarettes, agricultural burning, and fores...

p> Analysis of particulate matter (PM) is critical for the assessment of human exposures to potentially harmful agents, notably combustion-generated PM; specifically polycyclic aromatic hydrocarbons (PAHs) found in them and associated with carcinogenic and mutagenic effects. In this study, we quantify the presence and concentrations of PAHs with l...

The inhalation of particulate matter (PM) is a significant health risk associated with reduced life expectancy due to increased cardio-pulmonary disease and exacerbation of respiratory diseases such as asthma and pneumonia. PM originates from natural and anthropogenic sources including combustion engines, cigarettes, agricultural burning, and fores...

Arsenite is a highly toxic compound present in many water sources around the world. The removal of arsenite from water requires its oxidation to arsenate which is much more amenable to treatment using well attested technologies. Prior research has shown that the oxidation of arsenite by hydroxyl radicals is significantly accelerated in the presence...

This study examined effects of charges of molecules of natural organic matter (NOM) on its interactions with organic cations represented by toluidine blue (TB). NOM was exemplified in this study by Suwannee River (SR) and South Platte (SP) NOM. TB/NOM interactions were probed in the range of pH 3 to 11, DOC concentrations 0-10.6 mg L-1 and ionic st...

This study compared the binding of europium by soil and aquatic natural organic matter (NOM) exemplified by Pahokee Peat humic acid (PPHA) and Northern Reservoir NOM, respectively. NOM/Eu3+ interactions were measured based on the differential absorbance approach. The experimental results show that the binding of Eu3+ by humic acid isolated from agr...

The degradation of roxithromycin (ROX) by hydroxyl radical (·OH) generated by UV/H2O2 was systematically investigated in terms of degradation kinetics, effects of water chemistry parameters, oxidation products, as well as toxicity evaluation. The degradation of ROX by UV/H2O2 with varying light irradiation intensity, initial ROX concentration, and...

This study examined the formation of fouling films deposited on the surface of a polyethersulfone (PES) membrane during the filtration of alginate solutions with various ionic strengths. Membrane fouling was characterized by changes of the transmembrane pressure (TMP) and ex situ measured attenuated total reflectance (ATR) Fourier-transform IR (FTI...

This study focused on developing surrogate indicators for predicting oxidation of phenolic groups in dissolved organic matter (DOM), suppression of halophenols' formation potential and abatement of estrogenic activity during ozonation of water and wastewater. The evolution of pH-dependent differential absorbance spectra suggests that O3 preferentia...

Lead(IV) oxide PbO2 is one dominant solid phase in lead corrosion scales of drinking water distribution systems. Understanding the colloidal dispersion of PbO2 is important for lead control in drinking water, especially under scenarios of switching residual disinfectant from chlorine to chloramine. This study investigated changes of lead release an...

This study aimed to elucidate the intrinsic mechanisms of PS activation by carbon nanotubes (CNTs). Singlet oxygen generation ( ¹ O 2 ) and direct CNTs-mediated electron transfer were hypothesized to be two major pathways of the oxidation of 2,4-dichlorophenol (2,4-DCP) by PS in the presence of both unmodified and modified CNTs. For the first time,...

This study compared the experimental and theoretically calculated differential absorbance spectra (DAS)of quercetin, which is a typical model compound of natural organic matter (NOM)that is found in biochemical and environmental systems. Absorbance spectra of quercetin, which has five exchangeable protons, were generated at each state of deprotonat...

Chlorination of coastal (CS) and deep ocean (DO) seawater was accompanied by a prominent decrease (of up to 70%) of the intensity of its emission which was measured using a 315 nm excitation wavelength. Deconvolution of the emission spectra of CS and DO seawater showed that these spectra comprised three Gauss-shaped bands. The intensities of two of...

Exposure to airborne particulate matter (PM) from dissimilar sources such as cigarette smoking, combustion engines, agricultural, and forest fires can contribute to cardiovascular and respiratory diseases. Spectroscopic analysis of PAH compounds present in PM is used for source apportionment of potentially harmful particles, but this involves cumbe...

Solar irradiation of chlorine-containing waters enhances inactivation of chlorine-resistant pathogens (e.g., Cryptosporidium oocysts), through in situ formation of ozone, hydroxyl radical, and other reactive species during photolysis of free available chlorine (FAC) at UVB-UVA wavelengths of solar light (290–400 nm). However, corresponding effects...

Thermodynamic and structural aspects of the hydration of Pb(II) ions were explored based on DFT calculations combined with the supermolecular/continuum solvent model. Hydration of Pb(II) was considered as the formation of Pb(H2O)n2+ aqua complexes (n=6−9) from the gas phase Pb(II) ion. Hexa- and hepta-aqua Pb(II) complexes were shown to exhibit the...

Fluorescence of the hydrophobic acid fraction (HPOA) of Suwannee River natural organic matter and Tb³⁺ excitation spectra were measured in tandem using the instantaneous and time-resolved emission modes. The intensity of HPOA fluorescence decreased in the presence of Tb³⁺, while the intensity of the emission from Tb³⁺ cations bound by HPOA increase...

Iodinated contrast media (ICM) occur widely in the environment and are difficult to remove by conventional water treatment methods because of ICMs’ hydrophilicity and resistance to biodegradation. ICMs have also been shown to be precursors of toxic reaction products, notably iodine-containing trihalomethanes and haloacetic acids. This study examine...

Control of lead release from lead-containing materials galvanically coupled with copper or bronze represent a challenge for corrosion engineers and water treatment practitioners. Currently available data show that in some situations galvanically coupled lead remains passivated and releases little metal while in other cases, for instance those assoc...

Corrosion and metal release in drinking water systems are affected by the chemistry of ambient water (e.g., pH, concentrations of carbonate and other ions), stagnation/flow transitions associated with diurnal and seasonal changes of water consumption as well as the introduction of alternative water sources, for instance desalinated water. Control o...

This paper summarizes results of research on the electrochemical (EC) degradation of disinfection by-products (DBPs) and iodine-containing contrast media (ICMs), with the focus on EC reductive dehalogenation. The efficiency of EC dehalogenation of DBPs increases with the number of halogen atoms in an individual DBP species. EC reductive cleavage of...

This study examined the electrochemical (EC) reduction of iodinated contrast media (ICM) exemplified by iopamidol and diatrizoate. The method of rotating ring-disc electrode (RRDE) was used to elucidate rates and mechanisms of the EC reactions of the selected ICMs. Experiments were carried at varying hydrodynamic conditions, concentrations of iopam...

This review examines the potential of spectroscopic methods in online and real time water quality monitoring. Extensive research has shown that measurements of changes of absorbance and fluorescence of wastewater and drinking water during its treatment are predictive of the reduction of levels of trace-level organic contaminants (TrOC) or pathogens...

This study compared effects of chlorination and chloramination on the chromophores of dissolved organic matter (DOM) and attendant formation of disinfection by-products (DBPs) in raw and treated surface waters. Comparison of the differential absorbance spectra of chloraminated and chlorinated waters shows that interactions of chloramine with DOM ch...

The speciation, bioavailability and transport of Pb(II) in the environment are strongly affected by dissolved organic matter (DOM). Despite the importance of these interactions, the nature of Pb(II)-DOM binding is insufficiently attested. This study addressed this deficiency using the method of differential absorbance spectroscopy in combination wi...

This study investigated the applicability of fluorescence indexes based on the interpretation of excitation emission matrices (EEMs) by PARAFAC analysis and by selecting fluorescence intensities at a priori defined excitation/emission pairs as surrogates for monitoring the behavior of emerging organic compounds (EOCs) in two catchment basins impact...

This study examined the significance of changes of UV absorbance and fluorescence of dissolved organic matter (DOM) as surrogate indicators for assessing the formation of bromate and biodegradable dissolved organic carbon (BDOC) during the ozonation of surface water and wastewater effluent. Spectroscopic monitoring was carried out using benchtop UV...