Harada K.H.,Kyoto University |
Takasuga T.,Shimadzu Techno Research Incorporated |
Hitomi T.,Kyoto University |
Wang P.,Peking University |
And 2 more authors.
Environmental Science and Technology | Year: 2011
Short-chain chlorinated paraffins (SCCPs) persist in the environment and bioaccumulate in biota and are under review by the Stockholm Convention on persistent organic pollutants. SCCP levels were measured semiquantitatively in pooled 24 h food composite samples from Chinese (n = 10), Korean (n = 10), and Japanese (n = 40) adults in the 1990s and 2007-2009. In Japan, SCCPs were detected in 14 of 20 pooled samples in the 1990s and 13 of 20 pooled samples in 2009. Between these two time points, the geometric mean (GM) of the dietary intake of total SCCPs per body weight was comparable in Japan (54 ng kg-bw -1 day -1 in the 1990s and 54 ng kg-bw -1 day -1 in the 2000s). In Beijing, SCCP levels were elevated by 2 orders of magnitude from 1993 to 2009 (GM: 620 ng kg-bw -1 day -1 in 2009). The 95th percentile estimate of the dietary intake was 1200 ng kg-bw -1 day -1 (>1% of tolerable daily intake). In Seoul, no samples in 1994 contained detectable SCCP levels and only one sample in 2007 showed trace levels of SCCPs. Preliminary evidence on the significant increase in SCCP exposure in Beijing in 2009 warrants urgent investigations to refine dietary intake estimates by targeting food types and source identification. © 2011 American Chemical Society.
Ide Y.,Japan International Center for Materials Nanoarchitectonics |
Ide Y.,Waseda University |
Nagao K.,Waseda University |
Saito K.,Waseda University |
And 6 more authors.
Physical Chemistry Chemical Physics | Year: 2016
The activity of Au nanoparticle-loaded P25 TiO2 (Au/P25) plasmonic photocatalysts, evaluated by the oxidative decomposition of formic acid in water under visible light irradiation, was enhanced up to 3 times by simply mixing Au/P25 with photocatalytically inactive h-BN nanosheets as a result of electron transfer from photoexcited Au/TiO2 to the h-BN nanosheets and retardation of the charge recombination. © the Owner Societies 2016.
Taniyasu S.,Japan National Institute of Advanced Industrial Science and Technology |
Kannan K.,New York State Department of Health |
Wu Q.,New York State Department of Health |
Kwok K.Y.,City University of Hong Kong |
And 8 more authors.
Analytica Chimica Acta | Year: 2013
The ISO 25101 (International Organization for Standardization, Geneva) describes a new international standard method for the determination of perfluorooctanesulfonate (PFOS) and perfluorooctanoate (PFOA) in unfiltered samples of drinking and surface waters. The method is based on the extraction of target analytes by solid phase extraction, solvent elution, and determination by high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). For the determination of the performance of this method, more than 20 laboratories from 9 different countries participated in an inter-laboratory trial in 2006. In addition, inter-laboratory trials were conducted in 2008 and 2009 for the analysis of perfluoroalkylsubstances (PFASs), including PFOS and PFOA, in water samples by following the protocols of Japanese Industrial Standard (JIS). Overall, the repeatability coefficients of variation (i.e., within-laboratory precision) for PFOS and PFOA in all water samples were between 3 and 11%, showing a adequate precision of the ISO and JIS methods. The reproducibility coefficients of variation (i.e., between-laboratory precision) were found to vary within a range of 7-31% for surface water and 20-40% for wastewater. The recoveries of PFOS and PFOA, as a measure of accuracy, varied from 84 to 100% for surface water and from 84 to 100% for wastewater among the samples with acceptable criteria for internal standards recovery. The determined concentrations of PFASs in samples compared well with the " true" values. The results of the inter-laboratory trial confirmed that the analytical methods are robust and reliable and can be used as a standard method for the analysis of target compounds in water samples. © 2013 Elsevier B.V.
Han Z.-J.,Tokyo University of Science |
Yamagiwa K.,Tokyo University of Science |
Yabuuchi N.,Tokyo University of Science |
Son J.-Y.,Japan Synchrotron Radiation Research Institute |
And 7 more authors.
Physical Chemistry Chemical Physics | Year: 2015
Poly(acrylic acid) (PAH), which is a water soluble polycarboxylic acid, is neutralized by adding different amounts of LiOH, NaOH, KOH, and ammonia (NH4OH) aqueous solutions to fix neutralization degrees. The differently neutralized polyacid, alkali and ammonium polyacrylates are examined as polymeric binders for the preparation of Si-graphite composite electrodes as negative electrodes for Li-ion batteries. The electrode performance of the Si-graphite composite depends on the alkali chemicals and neutralization degree. It is found that 80% NaOH-neutralized polyacrylate binder (a pH value of the resultant aqueous solution is ca. 6.7) is the most efficient binder to enhance the electrochemical lithiation and de-lithiation performance of the Si-graphite composite electrode compared to that of conventional PVdF and the other binders used in this study. The optimum polyacrylate binder highly improves the dispersion of active material in the composite electrode. The binder also provides the strong adhesion, suitable porosity, and hardness for the composite electrode with 10% (m/m) binder content, resulting in better electrochemical reversibility. From these results, the factors of alkali-neutralized polyacrylate binders affecting the electrode performance of Si-graphite composite electrodes are discussed. © the Owner Societies 2015.
PubMed | Kyoto Bunkyo Junior College, Kyoto Koka Women's University, Kyoto University and Shimadzu Techno Research Incorporated
Type: Journal Article | Journal: PloS one | Year: 2016
Neonicotinoids, which are novel pesticides, have entered into usage around the world because they are selectively toxic to arthropods and relatively non-toxic to vertebrates. It has been suggested that several neonicotinoids cause neurodevelopmental toxicity in mammals. The aim was to establish the relationship between oral intake and urinary excretion of neonicotinoids by humans to facilitate biological monitoring, and to estimate dietary neonicotinoid intakes by Japanese adults.Deuterium-labeled neonicotinoid (acetamiprid, clothianidin, dinotefuran, and imidacloprid) microdoses were orally ingested by nine healthy adults, and 24 h pooled urine samples were collected for 4 consecutive days after dosing. The excretion kinetics were modeled using one- and two-compartment models, then validated in a non-deuterium-labeled neonicotinoid microdose study involving 12 healthy adults. Increased urinary concentrations of labeled neonicotinoids were observed after dosing. Clothianidin was recovered unchanged within 3 days, and most dinotefuran was recovered unchanged within 1 day. Around 10% of the imidacloprid dose was excreted unchanged. Most of the acetamiprid was metabolized to desmethyl-acetamiprid. Spot urine samples from 373 Japanese adults were analyzed for neonicotinoids, and daily intakes were estimated. The estimated average daily intake of these neonicotinoids was 0.53-3.66 g/day. The highest intake of any of the neonicotinoids in the study population was 64.5 g/day for dinotefuran, and this was <1% of the acceptable daily intake.
Takazawa Y.,Japan National Institute of Environmental Studies |
Takasuga T.,Shimadzu Techno Research Inc. |
Doi K.,Chiyoda Corporation |
Saito M.,Chiyoda Corporation |
Shibata Y.,Japan National Institute of Environmental Studies
Environmental Pollution | Year: 2016
Hexachlorocyclohexanes (HCHs), chlordanes (CHLs), and dichlorodiphenyltrichloroethanes (DDTs) in air-mass outflows from East Asia were recorded monthly from April 2009 to March 2014 at Cape Hedo in Japan. These organochlorine pesticides (OCPs) were collected by a high volume air sampler equipped with a quartz fiber filter, a polyurethane foam plug, and activated carbon fiber and analyzed by using a gas chromatograph-high resolution mass spectrometer. The overall (and geometric mean ± SD) concentration over the period was 4.9-43 pg m-3 (15 ± 7.8 pg m-3) in HCHs (sum of α-/β-/γ-/δ-HCH), 1.5-83 pg m-3 (8.8 ± 11 pg m-3) in CHLs (sum of cis-/trans-chlordane, cis-/trans-nonachlor, and oxychlordane), and 0.71-16 pg m-3 (2.5 ± 2.0 pg m-3) in DDTs (sum of o,p'-/p,p'-DDD, o,p'-/p,p'-DDE, and o,p'-/p,p'-DDT). Clear seasonal changes, i.e. higher in summer and lower in winter, were observed in HCHs and CHLs, suggesting the dominant effect of temperature-dependence, secondary sources in these OCPs. DDT concentration as well as the ratio of (o,p'-DDT + p,p'-DDT) to total DDTs, on the other hand, showed clear a declining trend during the five year sampling period, suggesting the decrease of input of newly produced DDTs in the regional environment by reflecting recent activities in the East Asian region to eliminate production and use of DDTs under the Stockholm Convention. © 2016 Elsevier Ltd.
PubMed | Shimadzu Techno Research Inc., Japan National Institute of Environmental Studies and Chiyoda Corporation
Type: | Journal: Environmental pollution (Barking, Essex : 1987) | Year: 2016
Hexachlorocyclohexanes (HCHs), chlordanes (CHLs), and dichlorodiphenyltrichloroethanes (DDTs) in air-mass outflows from East Asia were recorded monthly from April 2009 to March 2014at Cape Hedo in Japan. These organochlorine pesticides (OCPs) were collected by a high volume air sampler equipped with a quartz fiber filter, a polyurethane foam plug, and activated carbon fiber and analyzed by using a gas chromatograph-high resolution mass spectrometer. The overall (and geometric meanSD) concentration over the period was 4.9-43pgm(-3) (157.8pgm(-3)) in HCHs (sum of -/-/-/-HCH), 1.5-83pgm(-3) (8.811pgm(-3)) in CHLs (sum of cis-/trans-chlordane, cis-/trans-nonachlor, and oxychlordane), and 0.71-16pgm(-3) (2.52.0pgm(-3)) in DDTs (sum of o,p-/p,p-DDD, o,p-/p,p-DDE, and o,p-/p,p-DDT). Clear seasonal changes, i.e. higher in summer and lower in winter, were observed in HCHs and CHLs, suggesting the dominant effect of temperature-dependence, secondary sources in these OCPs. DDT concentration as well as the ratio of (o,p-DDT+p,p-DDT) to total DDTs, on the other hand, showed clear a declining trend during the five year sampling period, suggesting the decrease of input of newly produced DDTs in the regional environment by reflecting recent activities in the East Asian region to eliminate production and use of DDTs under the Stockholm Convention.
PubMed | University Institute of Health Sciences, Central South University, Kyoto University and Shimadzu Techno Research Incorporated
Type: | Journal: Chemosphere | Year: 2015
Short-chain chlorinated paraffins (SCCPs) are emerging persistent organic pollutants. It has been found that dietary intakes of SCCPs in China have recently increased and are now higher than in Japan and Korea. The contribution of cooking oil to dietary exposure to SCCPs in China was evaluated by analyzing SCCPs in cooking oil, raw seeds used to produce cooking oil, and fried confectionery products collected in China in 2010 and 2012. Detectable amounts of SCCP homologs were found in 48 out of the 49 cooking oil samples analyzed, and the SCCP concentrations varied widely, from <9 to 7500 ng g(-1). Estimated dietary intakes of total SCCPs in cooking oil ranged from <0.78 to 38 g d(-1). The estimated dietary intake of SCCPs was relatively high (mean 14.8 g d(-1)) for residents of Beijing. Fried confectionery was found to contain SCCP concentrations of 11-1000 ng g(-1). Cooking oil might therefore be one of the sources of SCCPs to Chinese diets. SCCPs were also detected in raw seeds used to produce cooking oil, but the concentrations varied widely. The SCCP homolog patterns in the raw seed and cooking oil samples were different, implying that the seeds used to produce the oil (and therefore the soil on which the seeds were produced) were unlikely to be the sources of SCCPs in cooking oil. Further investigations are needed to determine the routes through which cooking oil becomes contaminated with SCCPs during the production and processing of the oil.
Yang Y.,Environmental Quality Management |
Nakada N.,Environmental Quality Management |
Nakajima R.,Shimadzu Techno Research Inc. |
Yasojima M.,Shimadzu Techno Research Inc. |
And 2 more authors.
Journal of Hazardous Materials | Year: 2013
The rapid increase in the production and use of fullerene C60 nanoparticles raise concerns about environmental risks and human health. Wastewater treatment plants are key barriers to their discharge into the environment. The aggregation behavior of aqueous suspensions of C60 nanoparticles (nC60) could affect their transport, bioavailability, and removal during wastewater treatment. We tested the aggregation of nC60 in wastewater at different values of pH, ionic strength, and dissolved organic matter (DOM). The nC60 remained relatively stable in filtered wastewater under environmentally relevant conditions up to 24h. But at pH 3 or at high ionic strength (>100mM NaCl), the aggregate size increased greatly, reaching micrometer scale after only 1h. However, the aggregation behavior varied among wastewater samples even at values of similar zeta potential, compared with that in filtered secondary effluent and aeration tank liquor, that in filtered primary effluent was obviously inhibited. This inhibition could be attributed to the steric stabilization due to the adsorption of DOM on nC60 aggregate in addition to electrostatic stabilization. The aggregation results also suggest that membrane filtration could be improved by adjustments to pH. © 2012 Elsevier B.V.
Araoka F.,Tokyo Institute of Technology |
Masuko S.,Tokyo Institute of Technology |
Kogure A.,Shimadzu Techno Research Inc. |
Miyajima D.,University of Tokyo |
And 2 more authors.
Advanced Materials | Year: 2013
The self-organization of ferroelectric columnar liquid crystals (FCLCs) is demonstrated. Columnar order is spontaneously formed in thin films made by the wet-process due to its liquid crystallinity. Electric-field application results in high optical quality and uniform spontaneous polarization. Such good processability and controllability of the wet-processed FCLC films provide us with potential organic ferroelectric materials for device applications. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.