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Numerous reports have elucidated different statistical approaches to identify temporal trends in atmospheric persistent organic pollutant (POP) time series. However, the correlation of industrial activity with concentrations of atmospheric POPs in Japan has not yet been determined. Herein, a panel data analysis of a 16-year monitoring program (2003–2018) conducted by the Japanese Ministry of Environment was used to investigate a range of POPs in the atmosphere above Japan. This work focuses on polychlorinated biphenyls (PCBs), polychlorinated naphthalenes (PCNs), polybrominated diphenyl ethers (PBDEs), hexachlorobenzene (HCB), and pentachlorobenzene (PeCBz) collected each year at 53 sites across Japan. The panel analysis revealed that PCB, PCN, and PBDE concentrations were influenced by a combination of factors including year, industrial activity (municipal and industrial waste incinerators, cement kilns, steel industry, and secondary zinc production), population, temperature, and atmospheric boundary layer. However, HCB and PeCBz were not significantly affected by these factors. Industrial activity showed stronger positive correlations with all homologues of PCBs, PCNs, and PBDEs as compared to those demonstrated by population. Significant decreasing trends were identified for the atmospheric ∑ P B D E s (half-life t1/2 = 9.4 years), ∑ P C N s (t1/2 = 8.9 years), and ∑ P C B s (t1/2 = 13.5 years) concentrations, while HCB and PeCBz showed slightly increasing or steady levels. As a statistical tool, panel data analysis can contribute to the assessment of spatial and temporal trends of POPs at a national scale, while elucidating different behavioral responses to numerous environmental variables.

We estimated the in-use stocks of polybrominated diphenyl ethers (PBDEs) in Japan using a population balance model. The estimation is based on the domestic demand of PBDEs and the assumed survival rate of these products. Two cases relevant to the future regulation of commercial deca-BDE are considered, namely (1) deca-BDE declines at the same rate as the current rate of decline, and (2) deca-BDE is discontinued after 2020. The estimates of the decreasing rates of in-use penta-, octa-, and deca-BDE stocks were proportional with the measured decreases in the atmospheric concentrations of these substances. The in-use penta- and octa-BDE stocks could be depleted in the near future (500 and 60 tonne in 2013, and an estimated 20 and

In this study, we aim to determine the correlation between the height of the atmospheric boundary layer (ABL) and the concentrations of polybrominated diphenyl ether (PBDE) congeners, in an effort to improve comprehension of the atmospheric behavior of PBDEs. We used the PBDE data in air (n = 298), which were measured by the Japan Ministry of Environment (JMOE) at 50 sites across Japan during the period 2009-2012. The height of the ABL, which directly affects the PBDE concentrations in the near-surface air, was estimated by employing data retrieved from the Japanese global reanalysis (JRA-55) database, using the parcel and Richardson number method. The ABL has shown a strong inverse relationship with BDE-47 and BDE-99 (p0.01). In contrast, there was less correlation between BDE-209 and the ABL (p = 0.258). These differing behaviors could be explained by differences in particle size distribution of PBDEs, where BDE-47 and BDE-99 are associated with gas phases and fine particles and BDE-209 is associated with coarse particles. To our knowledge, this paper represents the first large-scale analysis of correlations between the ABL and the concentrations of PBDEs in the air.

This study analyzed polyhalogenated compounds (PHCs) such as brominated flame retardants (BFRs) in indoor air and dust samples from two modern homes in Japan. Concentrations of polychlorinated biphenyls (PCBs) and 2,4,6-tribromophenol (2,4,6-TBP) in exhaust and indoor air of two houses were detected at 10(2)-10(3)pgm(-3) order, which were well above those in outdoor air. For dust samples, the detected polybrominated diphenyl ether (PBDE) and polybrominated dibenzo-p-dioxins/furan concentrations resembled values found in our past study. Interestingly, compared to PBDE concentrations, two orders of magnitude higher concentration (13000 ng g(-1)) was observed for hexabromocyclododecanes (HBCDs) in a dust sample from one house. Based on the calculation of air/dust partition ratio values (Kad), low Kad values (log Kad

We used polybrominated diphenyl ether (PBDE) data in air at 38 sites across Japan (2009-2012), which were measured by the Japan Ministry of Environment (JMOE), to elucidate the time trend and seasonality of atmospheric PBDEs. In order to address few (7% for BDE-47) to many (63% for BDE-153 and 183) non-detect data, Tobit model, also called a censored regression model was used. The model revealed that the concentrations of PBDE congeners were influenced by a combination of year, temperature, rainfall rate, and population density. Greater declines were observed for BDE-47, -99, -153 and -183 (-21, -25, -17, -23%/year, p < 0.05) than for BDE-209 (-6%/year, p = 0.065). These trends were consistent with the estimated trends of penta-, octa- and deca-BDE contained in in-use products based on domestic demand for PBDEs in Japan and product lifespan. Seasonal patterns were opposite for light congeners (BDE-47 and -99), which increased with temperature, and heavy congeners (BDE-183, and -209), which decreased with temperature. Temperature-dependent emission (evaporation) for light congeners and temperature-independent emission (abrasion) for heavy congeners, coupled with seasonality of atmospheric boundary layer height, might explain these seasonal patterns. Human population density showed a positive correlation with all PBDE congener concentrations, whereas PBDEs showed negative correlation with rainfall rate.

Intake fractions (iFs) for emissions to air, water, and soil for 17 PCDDs/DFs and 12 Co-PCBs were calculated with a level III multimedia model and a food-chain exposure model in succession. The two integrated models were tested by comparing the predicted and measured concentrations in the environment and by comparing intakes through food. Measurement-based iFs were also calculated and compared with the model-based iFs. The air concentrations predicted by the fate model were close to the median of the observed concentrations, whereas the predicted soil and water concentrations were one-third to one-tenth the observed concentrations. This difference was large in case of PCDDs and Co-PCBs, which was explained by the past pollution such as commercial PCB products and PCDD impurities in chloronitrofen (CNP) and pentachlorophenol (PCP). For fish, the predicted and observed exposures agreed well each other. For meat and milk, the predicted exposures were about 10 times the observed exposures for PCDDs/DFs, whereas the predicted and observed values agreed well for Co-PCBs. When the model was modified to consider feeding of fish meal to livestock and geographic bias in feed-grass production, the predicted congener profile was comparable to the measured profile. The comparison also suggested that chickens should be modeled separately from other terrestrial livestock. The model-based iFs for air emission of OCDD and 2378-TCDD were 0.001% and 0.1%, respectively. The iFs of most Co-PCBs were higher than those of PCDDs/DFs. These iF differences suggest the importance of the fate factor in assessing emissions of the 29 congeners.

今後大量に廃棄されると考えられる薬剤処理木材には, 各種化学物質が残存していると考えられる。廃木材リサイクリングルートにおけるそれらのヒト健康リスクを評価するため, 曝露ポイントとして, 廃木材の1) 切断作業, 2) 室内利用をあげ, 経気道・経口曝露ルートによるガス状・粒子状の重金属類 (Cr, Cu, As) , PCP (ペンタクロロフェノール) , PCDD/DFs (ダイオキシン類) 及びPAHs (多環芳香族炭化水素) の曝露解析を行った。その結果, 廃木材切断作業や室内利用に伴う経気道及び経口での化学物質曝露量が日常レベルを大きく上回るほか, 継続的な曝露がヒト健康へのリスクを発癌リスク10-4にまで高める可能性が示唆された。

ヘキサクロロベンゼン (HCB) 排出量の推定と動的環境挙動モデルによるHCBの運命予測を組み合わせ, 底質中HCB濃度トレンドを推定した。HCB発生源として農薬 (PCP, PCNB, TCTP) 不純物, テトラクロロエチレン蒸留残渣焼却, 都市ごみ焼却を考慮した。この底質トレンド推定結果を琵琶湖北湖東岸と大阪湾西宮沖の底質コア濃度実測値と比較した。底質到達への時間遅れにより, HCB排出量トレンドとHCB底質濃度トレンドの差違を部分的に説明できた。琵琶湖と大阪湾の底質トレンドの違いは, 発生源と流入経路の違いを反映したものと思われる。

A 67-year-old, hepatitis C virus (HCV)-positive woman was admitted to our hospital because of proteinuria and leg edema. Laboratory examination showed decreased serum albumin and complement activity and positive cryoglobulin. The HCV RNA genotype was 1b with high viral load. Kidney biopsy showed membranoproliferative glomerulonephritis (MPGN) with capillary deposition of C3, IgM, and IgG, indicating HCV-associated glomerulonephritis. In addition to interferon (IFN) therapy, double-filtration plasmapheresis (DFPP) was performed to reduce HCV RNA blood levels in the early stage of IFN therapy. This treatment greatly reduced the viral load and induced clinical remission of MPGN, suggesting that DFPP plus IFN combination therapy may represent a potentially effective modality for refractory-type HCV-associated glomerulonephritis.

Television (TV) set components are highly flame resistant, with their added brominated compounds such as polybrominated diphenyl ethers (PBDEs). These compounds might be released indoors via dust, which presents a potential exposure pathway for humans in the home environment. In this study, we collected dust from inside TV sets and TV set component samples (parts of housing front cabinets, rear cabinets and circuit boards) of five sets used in Japan. We measured BFRs (i.e., PBDEs, tetrabromobisphenol A (TBBPA) and hexabromocyclododecanes (HBCDs)) and polybrominated dibenzo-p-dioxins/dibenzofurans (PBDD/DFs). Analytical results of the TV components showed that the concentrations of PBDEs, TBBPA and PBDFs (48,000 microg/g, 19,000 microg/g and 9600 ng/g as mean values, respectively) were all highest in the rear cabinets. The SigmaPBDD concentrations (460 ng/g as a mean value) detected were highest in the circuit board samples. The respective SigmaPBDE and SigmaPBDF concentrations in the dust samples were 67-500 microg/g (mean 300 microg/g) and 180-650 ng/g (mean 410 ng/g). Such concentrations were 2-3 orders of magnitude higher than those previously reported for house dust samples, which suggests that the brominated compounds are transferred from TV components into dust. Comparison of congener patterns of the brominated compounds in the dust identified the components as the source of these BFRs.

The Chinese Government ratified the Stockholm Convention on Persistent Organic Pollutants (POPs) on 25 June 2004. As a party to the Convention, China is preparing its National Implementation Plan (NIP), which must be finished and submitted to the Conference of the Parties before November 11, 2006. The emission inventory and strategy for reducing unintentionally formed products is a very complex and difficult part of the NIP. In this paper, we analyzed the potential sources of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans in China and calculated their possible emissions. We included municipal solid waste incineration, hazardous and medical waste incineration, pulp bleaching, sodium pentachlorophenate production and usage, illegal electrical and electronic waste ("e-waste") recycling, and ferrous and non-ferrous metal production, and prepared a preliminary analysis of dioxin emissions in China. The results show that ferrous metal production (104.2-6648.3g TEQ), non-ferrous metal production (2.6-3389.8 g TEQ), and sodium pentachlorophenate production and usage (120-368.0 g TEQ) should be major potential sources of dioxins and furans. Moreover, municipal solid waste and hazardous and medical waste incineration (35.5 g TEQ) should also be considered high priority sources owing to a rapidly increasing incineration ratio anticipated for the near future.

To investigate the effect of biofiltration (BF) on the ability of blood to supply oxygen to the peripheral tissues, a 2 week crossover study was conducted with bicarbonate hemodialysis (BcHD) and BF using 5 male patients with diabetic renal failure as subjects. BcHD and BF were performed for 4 h and 3.5 h per session, respectively. Blood gases, the pH of red blood cells (RBC-pH), and 2.3-diphosphoglycerate in RBC (RBC-2.3DPG) were measured during each treatment. After a 2 week BF treatment, the plasma HCO3− at the beginning of BF was significantly higher than that of BcHD (p < 0.01), and the blood pH improved with an elevated plasma bicarbonate level (p < 0.05). The RBC-pH at the beginning of BF was higher than that of BcHD (p < 0.05) although the RBC-pH at the end of both therapies increased to similar levels. The RBC-2.3DPG during BcHD remained unchanged, but during BF significantly increased (p < 0.05). Metabolic acidosis was significantly improved by BF with its effect reaching to the RBC intracellular level. The improved metabolic acidosis might occur as a result of the increase in RBC-2.3DPG during BF. This increase in RBC-2.3DPG has the effect of reducing the affinity of oxygen for hemoglobin and allows more oxygen to be delivered to the peripheral tissues although the increase in RBC-pH by dialysis restricts the dissociation of oxygen from hemoglobin.

Irradiation with visible light induced a remarkable effect on the reactivity of a metal-carbon bond in (tetraphenylporphinato)aluminum methyl in the nucleophilic substitution reaction with protic compounds such as phenol. A similar photoacceleration effect was also observed in the reversible ligand exchange of (tetraphenylporphinato)aluminum phenoxide with phenol. As for the former reaction, comparable quantum yields were observed upon irradiation at the Soret band and at the Q-band. 22 refs., 5 figs.

Irradiation with visible light induced a remarkable effect on the reactivity of a metal-carbon bond in (tetraphenylporphinato)aluminum methyl in the nucleophilic substitution reaction with protic compounds such as phenol. A similar photoacceleration effect was also observed in the reversible ligand exchange of (tetraphenylporphinato)aluminum phenoxide with phenol. As for the former reaction, comparable quantum yields were observed upon irradiation at the Soret band and at the Q-band. 22 refs., 5 figs.

Photochemical fixation of carbon dioxide is of much interest in connection with biological photosynthesis by green plants as well as from the viewpoint of carbon resource utilization. One of the important steps in the assimilation of carbon dioxide is the carboxylation of a carbonyl compound into ketocarboxylic acid, where the reaction proceeds via an enolate species as reactive intermediate. For example, in four carbon (C{sub 4}) pathway and Crassulacean acid metabolism (CAM) processes, pyruvate is converted with the aid of ATP into phosphoenolpyruvate, which is subsequently carboxylated to give oxaloacetate by the action of pyruvate carboxylase. In relation to this interesting biological process, some artificial systems have been exploited for the synthesis of {beta}-ketocarboxylic acid derivatives from carbon dioxide and ketones using nucleophiles such as metal carbonates, thiazolates, phenolates, alkoxides, and strong organic as well as inorganic basis, which promote the enolization of ketones in the intermediate step. We wish to report here a novel, visible light-induced fixation of carbon dioxide with the enolate complex of aluminum porphyrin, giving {beta}-ketocarboxylic acid under mild conditions.