Hiroaki Furumai

Hiroaki Furumai
The University of Tokyo | Todai · Faculty & Graduate School of Engineering

Doctor of Engineering

About

348
Publications
32,813
Reads
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5,232
Citations
Additional affiliations
April 2006 - February 2016
The University of Tokyo
Position
  • Professor, Research Center for Water Environment Technology
April 2006 - February 2016
The University of Tokyo
Position
  • Professor, Research Center for Water Environment Technology
April 2006 - February 2016
The University of Tokyo
Position
  • Professor, Research Center for Water Environment Technology

Publications

Publications (348)
Article
Nontuberculous mycobacteria (NTM) infection is estimated as the most serious waterborne infectious disease. NTM are ubiquitous in drinking water supply systems, which could be one of the possible exposure pathways for NTM disease, posing a serious concern to human health. Characteristics of NTM, such as exposure via inhalation, disinfectant resista...
Article
Full-text available
Antimicrobial resistance (AMR) is a serious public health concern. Many countries have implemented AMR surveillance programs for humans and animals, but a scheme for monitoring AMR in the environment has not yet been established. Class 1 integrons, which can acquire antimicrobial resistance genes (ARGs) to gene cassettes, were proposed as a candida...
Article
Full-text available
In premise plumbing, microbial water quality may deteriorate under certain conditions, such as stagnation. Stagnation results in a loss of disinfectant residual, which may lead to the regrowth of microorganisms, including opportunistic pathogens. In the present study, microbial regrowth was investigated at eight faucets in a building over four seas...
Article
Concurrence of pharmaceuticals and personal care products (PPCPs), pathogenic viruses, metals and microbial pollution along with their seasonal variations in the water environment are overarching in the context of existing pandemic, especially for tropical countries. The present study focuses on the seasonal influence on the vulnerability of urban...
Article
Full-text available
Many urban flood models employ coarse grids to reduce the computational cost of real‐time forecasting. Such a coarse grid, however, may result in poor predictions of the discharge rate of surface water because of difficulties in representing the detailed features of drainage facilities. In the present study, an urban flood model that consists of a...
Article
Full-text available
Microbial regrowth in premise plumbing is a threat to water safety. Disinfectant residuals are often diminished during water transportation and stagnation, leading to the regrowth of opportunistic pathogens. Although microbial regrowth potential is mostly determined by water treatment, little is known about how each treatment step affects two key f...
Article
Full-text available
Porous carbons are well-known efficient adsorbents for a variety of organic and inorganic pollutants; however, they have difficulty in virus removal. In this study, novel porous carbons (NPCs) (NPC-A, NPC-B, and NPC-C) derived from rice husks were compared with commercially available activated carbons (ACs) for their ability to remove MS2 bacteriop...
Article
Full-text available
We measured microplastics [(MPs): 10 μm–5 mm] in untreated and secondary-treated sewage, highway runoff, and estuarine water in Tokyo, Japan, during both dry and wet weather. MPs smaller than 200 μm were predominant, making up>60% of the total number, in all our water samples. The abundance of the MPs was 420 pieces/L in the influent and 8.7 pieces...
Article
Fecal indicator bacteria (FIB) are commonly used to evaluate the pollution impact of combined sewer overflows (CSOs) in urban rivers. Although water quality assessment with FIB has a long tradition, recent studies demonstrated that FIB have a low correlation with pathogens and therefore are not accurate enough for the assessment of potential human...
Article
Integrated flood models have been previously developed to simulate diverse inundation situations and combined with models of storm surges and river floods. However, drainage systems, ground elevation, and surface information of human settlements have only been digitized in large cities. Digitization of surface information is essential for developin...
Article
As rainfalls exceeding the designed level have increased, so has damage associated with pluvial flooding. Typhoon Hagibis, which swept Japan in 2019, left 140 municipalities in 15 prefectures scarred from flooding. The sewage networks damaged by the typhoon affected civic life by paralyzing urban functions, raising concerns in urban flood risk and...
Article
The series of annual flood disasters that struck Japan in recent years pose challenges to urban stormwater management. Japan has been implementing nation-wide hydrometeorological observation through a dense network of rain gauges. Since the recent decade, ground radars have been deployed to observe heavy rainfall with high spatiotemporal resolution...
Article
Full-text available
The Sumida river estuary of Tokyo bay is often affected by fecal contamination from combined sewer overflows (CSOs). This study monitored the surface water quality from the upstream of the Sumida river to the estuary in October 2017, June 2018, and July 2018 after three long-duration rainfall events. Several types of sewage markers, including fecal...
Article
This study aimed to classify the possible molecular formulas of precursors for disinfection by-products (DBPs) in raw, coagulated, and chlorinated water samples from the U-Tapao Canal, Songkhla, Thailand. The molecular formulas of DBPs in chlorinated water were investigated. Polyaluminum chloride (PACl) was employed as a coagulant. Orbitrap Fourier...
Article
Full-text available
Capsid integrity (RT-)qPCR has recently been developed to discriminate between intact forms from inactivated forms of viruses, but its applicability to identifying integrity of viruses in drinking water has remained limited. In this study, we investigated the application of capsid integrity (RT-)qPCR using cis-dichlorodiammineplatinum (CDDP) with s...
Article
Isolation of complex dissolved organic matter (DOM) from environmental water is a major challenge for unknown screening analysis by high-resolution mass spectrometry. In this study, DOM in process water during advanced drinking water treatment was fractionated sequentially by three solid-phase extraction (SPE) cartridges based on the polarity and c...
Article
To verify a statistical model for predicting urban pollutant runoff developed in our previous research, newly obtained runoff data were compared with those predicted by the model. The proposed model previously was a regression model using parameters representing geological, rainfall, and hydrological characteristics. The targeted pollutants were CO...
Article
Fecal pollution caused by combined sewer overflows has been observed at urban waterfronts after rainfall and results in fecal pollution levels exceeding bathing water quality standards. To guarantee the swimmablility of urban waterfronts, it is necessary to predict the situation of fecal contamination to ensure safe bathing. Therefore, we aimed to...
Article
This study developed a fate model of pharmaceuticals and personal care products (PPCPs), including acetaminophen, caffeine, and crotamiton, derived from combined sewer overflow (CSO) in the Tokyo coastal area. The target PPCPs were proposed as promising sewage markers having different persistency during treatment processes and in the environmental...
Article
Full-text available
Current challenges in the anaerobic bioremediation of benzene are the lack of capable cultures and limited knowledge on the biodegradation pathway. Under methanogenic conditions, benzene may be mineralized by syntrophic interactions between microorganisms, which are poorly understood. The present study developed an optimized formula for anoxic medi...
Article
Full-text available
The primary concentration and molecular process are critical to implement wastewater-based epidemiology for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, the previously developed methods were optimized for nonenveloped viruses. Few studies evaluated if the methods are applicable to the efficient recovery of enveloped viruse...
Article
In this review, we present the environmental perspectives of the viruses and antiviral drugs related to SARS-CoV-2. The present review paper discusses occurrence, fate, transport, susceptibility, and inactivation mechanisms of viruses in the environment as well as environmental occurrence and fate of antiviral drugs, and prospects (prevalence and o...
Article
Nitrification is a key function of biological activated carbon (BAC) filters for drinking water treatment. It is empirically known that the nitrification activity of BAC filters depends on water temperature, potentially resulting in the leakage of ammonium from BAC filters when the water temperature decreases. However, the ammonium removal capacity...
Article
Full-text available
Aims: A continuous quench-flow (CQF) reactor was developed to collect samples at the reaction times of less than one second. The reactor is applied to determine ozone disinfection kinetics of poliovirus and to study whether EMA-qPCR can assess the viral infectivity after ozone disinfection. Methods: Ozone disinfection of poliovirus was conducted...
Article
Escherichia coli normally cannot grow in the environment. One environmental stress that prevents E. coli growth may be the competition for growth substrates with co‐existing microorganisms. In this study, the growth substrates of E. coli were screened by high resolution mass spectrometry and compared with those of indigenous bacteria in river water...
Article
Rapid urbanization induces organic pollution in closed water bodies and accelerates eutrophication. Dissolved organic matter (DOM), a major fraction of organic matter, causes various problems in water use. DOM sources in lakes are diverse. Moreover, DOM properties can be altered biologically and physicochemically during retention time. However, DOM...
Article
Isotope dilution techniques (IDT) and sequential extraction procedures (SEPs) were compared to apprehend the differences between two techniques in determining metal exchangeability and vulnerability to pollute the urban groundwater. For this purpose, soil (n = 2), “soakaway” sediment deposited in the artificial infiltration facilities (AIF) (n = 4)...
Article
Recreational activities in coastal waters that are polluted by enteric viruses can result in gastroenteritis etc. In this study, the pollution profiles of enteric viruses were examined in the coastal area of Tokyo Bay, Japan, by collecting 57 water samples from three different depths (0.5 m, 3.0 m, and 5.0 m) during and after a series of heavy rain...
Book
Full-text available
This book talks about the dynamics of the surface water-groundwater contaminant interactions under different environmental conditions across the world. The contents of the book highlight trends of monitoring, prediction, awareness, learning, policy, and mitigation success. The book provides a description of the background processes and factors cont...
Article
Dissolved organic matter (DOM) causes organic pollution in lakes, resulting in the occurrence of off-flavour etc. when lake water is used for drinking water source. In this study, DOM in 11 major lakes in Japan was characterised by high-resolution Orbitrap mass spectrometry. Molecular formulas were assigned to 845–1,451 components per sample. Among...
Article
Assays based on the polymerase chain reaction (PCR) are widely applied to quantify enteric viruses in aquatic environments to study their fates and potential infection risks. However, inhibitory substances enriched by virus concentration processes can result in inaccurate quantification. This study aimed to find a method for improving virus quantif...
Article
Full-text available
Polymeric materials are widely used in premise plumbing. To assess the potential of pipe materials to promote microbial regrowth in drinking water, we incubated drinking water in a new cross-linked polyethylene pipe (N-PEX), a new steel pipe lined with powdered polyethylene (N-SPE), and an old steel pipe lined with powdered polyethylene (O-SPE). As...
Article
It is important to determine the infectivity of viruses in waters and foodstuffs so that the risk of viral infection can be assessed. The use of viability markers such as propidium monoazide (PMA), ethidium monoazide (EMA) and more recently cis-dichlorodiammineplatinum (CDDP) has been applied to discriminate between infectious and inactivated virus...
Article
Minato City has developed a forecasting system to determine the safety period of bathing at Odaiba Seaside Park using the database of model-calculated E. coli concentration change for each categorized rainfall. However, there are challenges to improve E. coli concentration prediction. Therefore, we revised the characteristics for categorizing rainf...
Article
Effects of sunlight and salinity inactivation on the fate of three types of fecal indicator bacteria (E. coli, Fecal coliform, and Enterococcus) and two types of potential viral indicators (F-specific bacteriophage and Somatic coliphage) in raw sewage were examined by laboratory experiments. F-specific bacteriophage was inactivated by salinity and...
Article
Full-text available
It is important to evaluate the removal of enteric viruses by drinking water treatment processes so that viral infection risk can be assessed and managed. However, evaluating the removal of enteric viruses by full-scale treatment processes can be challenging due to the low numbers of viruses and the presence of substances in the water samples that...
Article
Full-text available
VULNERABILITY AND RESILIENCE of urban waters, under the shifting paradigm of climate change and urbanization, needs to be evaluated from both quantitative and qualitative perspectives. We evaluated the vulnerability of urban waters of Guwahati, the largest city in Northeastern India, and Colombo, the coastal National Capital Territory of Sri Lanka,...
Conference Paper
Inundation hazard is one of the severest natural hazards nowadays, especially in the urbanized coastal lowland area. Real-time predication of urban inundation is highly demanded for disaster preparedness due to the increasing frequency of extreme weather events. In this study, an assimilation model and a databank-based assimilation method were deve...
Article
Reverse osmosis (RO) membrane is widely used for household water treatment in areas with limited access to safe drinking water; however, some studies documented deterioration in the quality of RO permeate. Repeated pressurization from intermittent operation in households is suspected to have an adverse effect on RO. This study aimed to evaluate vir...
Article
Full-text available
Multi-drug resistant microbes, pathogenic viruses, metals, and pharmaceuticals and personal care products (PPCPs) in water has become the crux of urban sustainability issues. However, vulnerability due to pollutant concurrences, source apportionment, and identification of better faecal indicators needs to be better understood. The present study foc...
Article
We investigated semiquantitative changes in almost 1000 dissolved organic matter (DOM)features during oxidation with 1 mg of O 3 per liter (mg O 3 /L), 4 mg O 3 /L, or 4 mg O 3 /L + 2.5 mg of H 2 O 2 per liter (advanced oxidation process, AOP)by unknown screening analysis with Orbitrap mass spectrometry. The consequential effects on formation of un...
Article
Full-text available
This study is aimed to investigate biological oxidation of arsenic [As(III)] in sand component of arsenic–iron removal plant (AIRP). Water and sand samples were collected from the municipal and household AIRP units (MAIRP and HAIRPs) at Manikganj district, Bangladesh. These samples were analyzed using arsenic speciation cartridge with inductively c...
Article
Reverse osmosis (RO) membranes are commoditized and available for household water treatment (HWT) in areas where access to safe water is limited. The RO membranes for HWT (residential RO) are typically operated intermittently without a cleaning process. This suggests that a unique mechanism of membrane deterioration, membrane oxidation, as one of t...
Article
Full-text available
The presence of pathogenic viruses in drinking water is a major public health concern. Although viability RT-qPCR methods were developed to quantify infectious viruses, they may not always reflect viral infectivity, therefore leading to false-positive results. In this study, sodium deoxycholate (SD) pre-treatment was used to improve the efficiency...
Article
During runoff process, the urban road dust (URD) passes through the road-side gutters and detention tanks, where it gets hold for a certain period of time, hours to weeks, before making its way into the water bodies. A part of the water-exchangeable toxicants are leached by the water, and some strongly bound toxicants remain attached to the URD. To...
Article
In 2016, only 56.7% of the lakes and reservoirs in Japan complied with the standard of chemical oxygen demand determined by permanganate (CODMn). The dissolved organic matter (DOM) contributing to CODMn in lakes is heterogenous in nature; hence, DOM compositions in different lake waters are not well known. In this study, molecular components contri...
Article
Urban flood damage caused by heavy rainfall during storms has been increased and therefore the effective use of existing flood control facilities is important. However, we have limited understanding of how the sewer systems, which design is based on the rational formula, would work against the heavy rainfall which is not uniform in space and time....
Article
Water drained through sewer network installed in lower-lands shows complex behavior due to influence from pumping station and exhibits non-linearity in rainfall-runoff relation. Also validation of sewer network model is not sufficient due to lack of observed data. Present study validates urban inundation models by using water levels observed in sto...
Article
Full-text available
Granular activated carbon (GAC) has been widely introduced to advanced drinking water purification plants to remove organic matter and ammonium. Backwashing, which is the routine practice for GAC maintenance, is an important operational factor influencing the performance of GAC and its microbial biomass. In this study, the effects of backwashing on...
Article
Nitrification is a major ecological process occurring in biological activated carbon (BAC) filters used for advanced drinking water treatment. Ammonia oxidation is a rate-limiting step in nitrification that depends on the activity of ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB) associated with BAC. However, the growth compet...
Article
Molecular assays are currently the most widely used method to quantify pathogenic viruses in water; however, their performance is often disrupted by matrices present in environmental samples. The present study used ferrihydrite (Fh) treatment to mitigate inhibition of RT-qPCR virus detection from environmental water concentrates. Fh treatment was p...
Article
Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous in urban environments. Urban road dust (URD) generated by traffic is an important PAH accumulator. Twelve priority PAHs in < 2000 µm fraction of ten URD samples from Tokyo, Japan were characterized based on profile distributions, carcinogenicity, toxicity, and source apportionment by cluster an...
Article
Real-time prediction of urban inundation during heavy rainfall is a challenging because a lot of computation time is necessary to analyze hydraulic condition in huge sewer networks. Therefore, a sewer network lumping method was proposed, in which the runoff process was properly expressed by adjusting the non-linear reservoir model parameter of catc...
Article
Due to increasing stringency of water legislation and extreme consequences that failure to detect some contaminants in water can involve, there has been a strong interest in developing electrochemical biosensors for algal toxins detection during last decade, evidenced by literature increasing from 2 journal papers pre-2009 to 24 between 2009 and 20...
Conference Paper
The issue of Global climate change has recently gained momentum due to its impacts on the environment and its components. Anthropogenic activities like deforestation, agricultural practices, burning of fossil fuels etc. have contributed to the rapid change in the global climate. Disruption of river flows, mobility, dilution of contaminants, effect...
Article
Molecular changes in dissolved organic matter (DOM) from treatment processes at two drinking water treatment plants in Japan were investigated using unknown screening analysis by Orbitrap mass spectrometry. DOM formulae with carbon, hydrogen and oxygen (CHO-DOM) were the most abundant class in water samples, and over half of them were commonly foun...
Article
In order to predict inundation in an urban river basin during heavy rainfall, numerical model analysis with consideration of sewer pipe networks is essential. However, it is too difficult to predict inundation phenomena in real-time because the numerical analysis is time-consuming due to the large number and complex nature of sewer pipe networks. T...
Article
Full-text available
To assess the potential risk of viral infection through drinking water, a rapid and effective method to quantify pathogenic viruses is necessary. Ethidium monoazide (EMA) combined with reverse transcription qPCR (EMA-RT-qPCR) is a currently widely accepted method to assess the integrity of viruses. However, this technique can be hampered by humic a...
Article
Water sampling was conducted in the coastal area of Tokyo following two rainfall events in October and November 2016. The coastal area receives, through urban rivers, a considerable amount of combined sewer overflow (CSO) pollutants from overflow chambers and pumping stations. Five pharmaceutical and personal care products (PPCPs) including acetami...
Article
It is important to consider wide-area water supply and asset management in an integrated manner to realize sustainable water supply systems. However, there is no established planning method for long-term operation and renewal of wide-area water supply systems which is adapted to temporal change of constraints such as water source availability, futu...
Article
On the rise of heavy rainfall that rivals storm rainfall management capacity in urban areas, there has been increasing demand to apply XRAN and high-resolution precipitation nowcasts for storm rainfall management. However, as drainage areas of swerage network is relatively small and flood concentration time is farely quick, one needs to aqequately...
Article
Under the increasing trend of the heavy rainfall with the magnitude exceeding the designed control level, it is necessary to comprehensively operate existing available stock of flood reduction measures such as flood control facilities in a river and a management system of sewer network. It is also necessary to evaluate how the drained water through...
Article
Coastal recreational areas in Tokyo such as Odaiba Seaside Park have been polluted by combined sewer overflows (CSOs). Surface water sampling was conducted from upstream of the Sumida River to the Odaiba coastal area after rainfall events in October and November 2017. Four types of fecal indicator bacteria (E. coli, Total coliform, Fecal coliform a...
Article
To assess the potential of pepper mild mottle virus (PMMoV) as a viral process indicator, its reduction through coagulation-sedimentation (CS) and rapid sand filtration (RSF) were compared with those of Escherichia coli, previously used viral indicators, and norovirus genotype II (NoV GII; enteric virus reference pathogen) in a bench-scale experime...
Article
Quantitative detection of pathogenic viruses in the environmental water is essential for the assessment of water safety. It is known that some of natural organic substances interfere with virus detection processes, i.e., nucleic acid extraction and reverse transcription-PCR. Such substances are carried over into a sample after virus concentration....
Article
Urbanized coastal low-lying area has vulnerability against flood and inundation, which are caused by multiple flood causing factors occurring in coast, river and urbanized areas. Integrated flood prediction model, “Seamless Model”, has been developed to simulate inundation caused by tsunami, storm surge, as well as river flood and urban inundation....