Publications by authors named "Teruyuki Umita"

9 Publications

  • Page 1 of 1

Degradation of the endocrine-disrupting 4-nonylphenol by ferrate(VI): biodegradability and toxicity evaluation.

Environ Sci Pollut Res Int 2022 Mar 27;29(13):18882-18890. Epub 2021 Oct 27.

Course of Civil and Environmental Engineering, Department of System Innovation Engineering, Faculty of Science and Engineering, Iwate University, Ueda 4-3-5, Morioka, 020-8551, Japan.

4-Nonylphenol (4-NP) is an endocrine-disrupting and persistent chemical and is partially degraded in conventional wastewater treatment processes. Ferrate(VI) can be used as an environment-friendly oxidizing agent to mediate 4-NP degradation. Thus, this paper evaluates the biodegradability of 4-NP and its degradation products after the addition of ferrate(VI). The biodegradability was examined using NP labeled with C as a tracer and activated sludge microorganisms as an inoculum. The addition of ferrate(VI) to the 4-NP solution spiked with the tracer resulted in no remarkable decrease in the concentration of C, indicating incomplete mineralization of 4-NP and formation of degradation products. The degradation products from 4-NP with Fe(VI) were estimated based on mass spectra, which detected a unique peak at m/z 223 at low intensity. Four hydrogen atoms might have been added to 4-NP by degradation with Fe(VI). In addition, the effect of ferrate(VI) concentration on the estrogenic activity of 4-NP in an aqueous solution was investigated using a yeast bioassay. The results show that estrogenic activity was significantly decreased at a mass ratio of Fe(VI) to 4-NP greater than or equal to 2.5.
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http://dx.doi.org/10.1007/s11356-021-17167-1DOI Listing
March 2022

Removal of nonylphenol and nonylphenol monoethoxylate from water and anaerobically digested sewage sludge by Ferrate(VI).

Chemosphere 2019 Dec 18;236:124399. Epub 2019 Jul 18.

Course of Civil and Environmental Engineering, Department of System Innovation Engineering, Faculty of Science and Engineering, Iwate University, Morioka, 020-8551, Japan.

Nonylphenol (NP) and nonylphenol monoethoxylate (NP1EO) have toxic and persistent characteristics, and are incompletely degraded in conventional wastewater treatment processes. These compounds are present in sewage sludge that can be reused as fertilizers or soil conditioners. Accordingly, NP and NP1EO should be properly removed before being discharged in the environment. In this study, potassium ferrate (KFeO) containing hexavalent iron (Fe(VI)) was used as an environment-friendly oxidizing agent to mediate NP and NP1EO degradation. The aim of this study was to investigate the effects of pH and Fe(VI) dosage on the degradation of NP and NP1EO in water and anaerobically digested sewage sludge samples. In water samples, under conditions examined in this study, maximum removal efficiencies for NP and NP1EO were 98% and 92%, respectively. For digested sewage sludge samples, the maximum removal efficiencies of NP and NP1EO were 58% and 96%, respectively. The results demonstrated that Fe(VI) can potentially degrade NP and NP1EO in water and digested sewage sludge samples. However, organic matter as a matrix in the sludge sample would inhibit the degradation of NP and NP1EO by Fe(VI). The pH values before and after adding KFeO to the samples had an obvious influence on the removal of NP and NP1EO.
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http://dx.doi.org/10.1016/j.chemosphere.2019.124399DOI Listing
December 2019

Determination of tylosin excretion from sheep to assess tylosin spread to agricultural fields by manure application.

Sci Total Environ 2018 Aug 28;633:399-404. Epub 2018 Mar 28.

Faculty of Science and Engineering, Iwate University, Ueda 4-3-5, Morioka, Iwate 020-8551, Japan.

Antibiotics administered to livestock are partly excreted with urine and feces. As livestock excrement is used as manure on agricultural fields, soil may be contaminated by excreted antibiotics, potentially resulting in the development of antibiotic-resistant bacteria. Therefore, it is necessary to determine the amount of antibiotic administered to livestock that could spread to agricultural fields through manure application. This study reveals the excretion ratio of tylosin from sheep. After developing an analysis procedure for tylosin in urine and feces from sheep, a tylosin excretion study was performed with two sheep. Tylosin was excreted in urine and feces for four days, after which its concentrations dropped below the limits of quantification (urine: 0.5μg/kg, feces: 2.4μg/kg). The total excretion ratio was 11% on average. The results of our study can provide useful knowledge for treating excrement in order to prevent the spread of antibiotics to agricultural fields through manure application.
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http://dx.doi.org/10.1016/j.scitotenv.2018.03.216DOI Listing
August 2018

Cesium and strontium loads into a combined sewer system from rainwater runoff.

J Environ Manage 2016 Dec 28;183(Pt 3):1041-1049. Epub 2016 Sep 28.

Dept. of Science and Engineering, Iwate University, Ueda 4-3-5, Morioka, Iwate, 020-8551, Japan.

In this study, combined sewage samples were taken with time in several rain events and sanitary sewage samples were taken with time in dry weather to calculate Cs and Sr loads to sewers from rainwater runoff. Cs and Sr in rainwater were present as particulate forms at first flush and the particulate Cs and Sr were mainly bound with inorganic suspended solids such as clay minerals in combined sewage samples. In addition, multiple linear regression analysis showed Cs and Sr loads from rainwater runoff could be estimated by the total amount of rainfall and antecedent dry weather days. The variation of the Sr load from rainwater to sewers was more sensitive to total amount of rainfall and antecedent dry weather days than that of the Cs load.
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http://dx.doi.org/10.1016/j.jenvman.2016.09.067DOI Listing
December 2016

Fate of radiocesium in sewage treatment process released by the nuclear accident at Fukushima.

Chemosphere 2013 Oct 6;93(4):689-94. Epub 2013 Jul 6.

Department of Civil and Environmental Engineering, Iwate University, Ueda 4-3-5, Morioka, Iwate 020-8551, Japan. Electronic address:

The nuclear accident at the Fukushima Daiichi Nuclear Power Plant (FDNPP) which occurred after the Great East Japan Earthquake on March 11, 2011 resulted in releases of radionuclides such as (134)Cs (half-life:T1/2=2.06 yr), (137)Cs (T1/2=30.04 yr) and (131)I (T1/2=8.05 d) to the environment. For this paper, we observed the monthly variations of radiocesium ((134)Cs and (137)Cs) and stable Cs concentrations in influent, effluent, sewage sludge, and sludge ash collected from a sewage treatment plant 280 km north of the FDNPP from July to December, 2011. Using the stable Cs results, we concluded the mass balance of Cs in the sewage treatment plant showed that about 10% of the Cs entering the sewage treatment plant would be transferred to the sewage sludge, and then Cs in the sewage sludge was totally recovered in the sludge ash. The behavior of Cs was similar to that of Rb, but it was not similar to that of K in the sewage treatment process.
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http://dx.doi.org/10.1016/j.chemosphere.2013.06.012DOI Listing
October 2013

Fate of stable strontium in the sewage treatment process as an analog for radiostrontium released by nuclear accidents.

J Hazard Mater 2013 Sep 29;260:420-4. Epub 2013 May 29.

Department of Civil and Environmental Engineering, Iwate University, Ueda 4-3-5, Morioka, Iwate 020-8551, Japan.

Radionuclides were widely released into the environment due to the nuclear accident at the Fukushima Daiichi Nuclear Power Plant. Some of these radionuclides have flowed into municipal sewage treatment plants through sewer systems. We have observed the fate of stable Sr in the sewage treatment process as a means to predict the fate of radiostrontium. Concentrations of stable Sr were determined in sewage influent, effluent, dewatered sludge, and incinerated sewage sludge ash collected from a sewage treatment plant once a month from July to December 2011. In the mass balance of Sr in the sewage treatment plant, 76% of the Sr entering the plant was discharged to the receiving water on average. Additionally, 14% of the Sr flowing through the plant was transferred to the sewage sludge and then concentrated in the sludge ash without being released to the atmosphere. We also investigated Sr sorption by activated sludge in a batch experiment. Measurements at 3 and 6h after the contact showed Sr was sorbed in the activated sludge; however, the measurements indicated Sr desorption from activated sludge occurred 48 h after the contact.
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http://dx.doi.org/10.1016/j.jhazmat.2013.05.038DOI Listing
September 2013

Biological oxidation of arsenite in synthetic groundwater using immobilised bacteria.

Water Res 2012 Oct 20;46(15):4825-31. Epub 2012 Jun 20.

Department of Frontier Materials and Function Engineering, Iwate University, Ueda 4-3-5, Morioka 020-8551, Japan.

Biological oxidation of arsenite (As(III)) in synthetic groundwater was examined by using arsenite oxidising bacteria (AOB) isolated from an activated sludge. The phylogenetic analysis indicated that the isolated AOB was closely related to Ensifer adhaerens. Batch experiments showed that for an As(III) oxidation with the isolated AOB the optimum ratio of nitrogen source (NH₄-N) concentration to As(III) concentration was 0.5 (52 mg/L-110 mg/L) and the isolated AOB preferred pH values ranging from 6 to 8, and water temperatures greater than 20 °C. Further continuous experiments were conducted using a bioreactor with immobilised AOB. With an initial As(III) concentration of 1 mg/L at a hydraulic retention time (HRT) of 1 h, an As(III) oxidation rate was around 1 × 10⁻⁹ μg/cell/min and an As(III) oxidation efficiency of 92% was achieved. Although the maximum oxidation rate measured at an HRT of 0.5 h was 2.1 × 10⁻⁹ μg/cell/min, the oxidation efficiency decreased to 87%. These results advocate that a biological process involving immobilised AOB may be useful as an economical and environmentally friendly pre-treatment step for As removal from groundwater.
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http://dx.doi.org/10.1016/j.watres.2012.06.013DOI Listing
October 2012

Biotransformation of arsenic species by activated sludge and removal of bio-oxidised arsenate from wastewater by coagulation with ferric chloride.

Water Res 2008 Dec 6;42(19):4809-17. Epub 2008 Sep 6.

Department of Civil and Environmental Engineering, Iwate University, Ueda 4-3-5, Morioka 020-8551, Japan.

The potential of activated sludge to catalyse bio-oxidation of arsenite [As(III)] to arsenate [As(V)] and bio-reduction of As(V) to As(III) was investigated. In batch experiments (pH 7, 25 degrees C) using activated sludge taken from a treatment plant receiving municipal wastewater non-contaminated with As, As(III) and As(V) were rapidly biotransformed to As(V) under aerobic condition and As(III) under anaerobic one without acclimatisation, respectively. Sub-culture of the activated sludge using a minimal liquid medium containing 100mg As(III)/L and no organic carbon source showed that aerobic arsenic-resistant bacteria were present in the activated sludge and one of the isolated bacteria was able to chemoautotrophically oxidise As(III) to As(V). Analysis of arsenic species in a full-scale oxidation ditch plant receiving As-contaminated wastewater revealed that both As(III) and As(V) were present in the influent, As(III) was almost completely oxidised to As(V) after supply of oxygen by the aerator in the oxidation ditch, As(V) oxidised was reduced to As(III) in the anaerobic zone in the ditch and in the return sludge pipe, and As(V) was the dominant species in the effluent. Furthermore, co-precipitation of As(V) bio-oxidised by activated sludge in the plant with ferric hydroxide was assessed by jar tests. It was shown that the addition of ferric chloride to mixed liquor as well as effluent achieved high removal efficiencies (>95%) of As and could decrease the residual total As concentrations in the supernatant from about 200 microg/L to less than 5 microg/L. It was concluded that a treatment process combining bio-oxidation with activated sludge and coagulation with ferric chloride could be applied as an alternative technology to treat As-contaminated wastewater.
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http://dx.doi.org/10.1016/j.watres.2008.08.027DOI Listing
December 2008

Influence of water and sediment quality on benthic biota in an acidified river.

Water Res 2005 Jul;39(12):2517-26

Department of Civil and Environmental Engineering, Iwate University, Ueda 4-3-5, Morioka 020-8551, Japan.

Water and sediment quality and benthic biota were investigated in all seasons during three years in the River Akagawa that receives the effluent from a mine drainage treatment plant at its upstream site. The upper reaches kept the low pH, the comparatively high concentrations of metals and a large amount of iron deposited on the riverbed. The predominant macroinvertebrates were Protonemura sp., Capnidae, Nemoura sp. and Chironomidae in the upper and middle reaches. In the lowest reaches, the community structure of the macroinvertebrate changed into Chironomidae, Trichoptera (Hydropsychidae) and Ephemeroptera (Baetis sp.) as the pH was increased. From the results of multivariate analyses, it was found that the restoration of pH and attached algae and the increase in the concentrations of nutrients and organic matter promoted the inhabitation of Chironomidae and Hydropsychidae, whereas the dissolved metals in the river water inhibited the inhabitation of these families. Moreover, the sedimentation of metals would cause a severe damage to the inhabitation of Hydropsychidae compared with that of Chironomidae.
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http://dx.doi.org/10.1016/j.watres.2005.04.047DOI Listing
July 2005
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