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Wastewater, aeration gas, dewatered sludge, and incineration ash and flue gas (from dewatered sludge) were collected from 9 sewage treatment plants (STPs) located in Saitama Prefecture, Japan, and analyzed for seven cyclic and linear volatile methylsiloxanes (VMSs) namely, D3, D4, D5, D6, L3, L4, and L5. The mass loadings and distribution of VMSs in STPs were estimated based on measured concentrations in liquid, solid, and gaseous samples, including incinerated dewatered sludge. Mass loading of ΣVMS varied widely from 21 kg y−1 to 3740 kg y−1, depending on the volume of wastewater treated in each STP. Mass % of ΣVMS distributed in aeration gas was 15% and that in activated sludge was 78%. Approximately 6.6% of ΣVMS remained in the final effluent. Overall, partitioning onto the activated sludge was the dominant removal mechanism for D4, D5, and D6, whereas volatilization was also an important removal mechanism for D4. Incineration was effective to degrade VMSs in dewatered sludge, with a reduction rate of >99%. Activated carbon treatment removed >99% of VMSs from the aeration gas. In Saitama Prefecture, total emission of ΣVMS via STPs was estimated at 434 kg y−1, 86 kg y−1, and 0.065 kg y−1, to aquatic, atmospheric, and terrestrial environments, respectively, which accounted for 83%, 17%, and 0.01% of the total environmental emissions. Our results indicate that majority of VMSs in dewatered sludge can be removed by incineration and emission of VMSs through incineration ash landfill is negligible.

The large production volume of methylsiloxanes (MSs), combined with their high mobility/volatility and persistence, is a matter of concern from the atmospheric pollution perspective. Therefore, we evaluated of the concentrations and emission sources of MSs, including 7 cyclic methylsiloxanes (D3–D9; CMSs, the number refers to the number of Si–O bonds) and 13 linear methylsiloxanes (L3–L15; LMSs) in ambient air collected from Saitama, Japan. This is a first study regarding the evaluation of 20 methylsiloxanes in the Japanese atmosphere. We improved the air sampling methodology by determination the stability of D5 during a 7-d air sampling and arbitrary sample storage period using polystyrene-divinyl benzene copolymer sorbent (Sep-Pak plus PS-2). We analyzed air samples for MSs seasonally collected from nine locations in Saitama, including urban, suburban, rural, and mountainous areas. The mean CMS and LMS concentrations were 358 ng m−3 and 13.4 ng m−3, respectively. The D5 concentrations were distributed widely, with high concentrations in urban/suburban populous areas and dispersed at low concentrations in surrounding areas (north and mountainous areas). We analyzed 7-d air samples collected every week over a year and found apparent seasonal and periodic trends in the CMS concentrations. In the diurnal sampling campaign, we observed periodic fluctuations in ambient CMSs, with an inverse relationship with the atmospheric boundary layer development during the day. Backward trajectories and the prevailing wind direction during the sampling period indicated that the specific profiles of D4 observed in fall/winter weeks and north of Saitama could be ascribed to northwestward air-mass advection. We employed a novel approach in estimating CMSs emission sources and source apportionment by using non-negative matrix factorization (NMF). The concentration matrix was divided successfully into two factors (emission sources) namely, personal care and household products and industrial activities.

Surface waters including river water and effluent from sewage treatment plants (STPs) were collected from Tokyo Bay watershed, Japan, and analyzed for seven cyclic and linear volatile methylsiloxanes (VMSs), i.e., D3, D4, D5, D6, L3, L4, and L5 by an optimized purge and trap extraction method. The total concentrations of seven VMSs (ΣVMS) in river water ranged from

39th International Symposium on Halogenated Persistent Organic Pollutants；2019.8.25-30；Kyoto

During the process of treating and recycling Municipal Solid Waste Incinerators (MSWIs) fly ash, polychlorinated dibenzo-p-dioxins (PCDD/Fs) and polychlorinated dibenzofurans (dl-PCBs) in fly ash may potentially mobilize in the atmosphere and be widely distributed in the environment because of the inevitable re-suspension. Thus, this work presents the distributions of PCDD/Fs and dl-PCBs in inhalable coarse particles (Dp10-2.5 (particle diameter in μm)), fine particles (Dp

We investigated the capability of microorganisms isolated from environments polluted with perfluoroalkyl adds (PFAAs) to conduct biotransformation of these emerging pollutants. Two different microbial consortia (chemoorganoheterotrophic bacteria and total yeast and molds) were isolated from two river sediments in Saitama and Osaka, Japan, known for long term pollution with perfluorooctane sulfonic acid (PFOS) and perfluorooctanoic acid (PFOA). The microbial consortia were incubated in the presence of added PFOS and PFOA, and decreases in concentrations of these compounds were between 46-69% and 16-36%, respectively. Decreases in concentrations were, in part, due to sorption on biomass, but defluorinated PFOS and PFOA products were not detected. However, untargeted analysis suggested the presence of several metabolites found only in samples from consortia with PFOS and PFOA but not in the control samples. Molecular formula candidates were narrowed down to two options, C18H28O5F and C21H27O4. It was assumed that these formulas were associated with unsaturated monofluorinated fatty acids and hydrocarbons with multiple unsaturated bonds or ring structures. (C) 2018 Elsevier B.V. All rights reserved. Supplementary material: [http://cherry.chem.bg.ac.rs/handle/123456789/3114]

MSWI fly ashes sampled from 15 large-scale commercial municipal solid waste incineration plants in China were analyzed for seventeen polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/PCDFs) as well as twelve dioxin-like polychlorinated biphenyls (dl-PCBs). The concentration of PCDD/PCDFs and dl-PCBs in fly ash samples ranged from 2.8 to 190 ng g−1, and 59.6 ng g−1 on average. The toxic equivalent (TEQ) ranged from 34 to 2500 ng WHO(2005)-PCDD/PCDF-PCB-TEQ kg−1, and 790 ng WHO(2005)-PCDD/PCDF-PCB-TEQ kg−1 on average. For PCDDs, hexa-chlorinated homolog was the dominant compound except two fly ash samples. Tetra-chlorinated homolog was dominant for PCDFs except one sample. The ratio of PCDDs/PCDFs ranged from 0.32 to 2.44 (average 0.97). The contribution of dl-PCBs to total concentration and TEQ was relatively minimal. Correlation between the concentration of three congeners and total TEQ values of fly ashes was also established. The findings obtained in this work provided overview information on the PCDD/PCDF-PCB content characterization of MSWI fly ash in China, which can be available for MSWI fly ash management in the environment.

An urban river, Kamo River, located at the southern part of Saitama Prefecture had been found to be seriously polluted by nonylphenol (NP). Concentrations of nonylphenolic compounds (NP, nonylphenol ethoxylates, nonylphenoxy acetic acids) in the effluents from and the chemical products used in a dyes production factory, an industrial laundry, four gas stations, two car washing stations and a rubber product manufacturing factory were determined, and their characteristics were evaluated. The concentration of nonylphenolic compounds were ranged from 3.2 to 1,600 μg/L in the effluents. Seven out of 33 chemical products (detergents, dispersants, waxes) used in the factories and the stations contained nonylphenolic compounds of 1.1 μg/g to 0.97g/g. An annual emission load of nonylphenolic compounds in the effluent from the rubber product manufacturing factory, whose nonylphenolic compounds detected was 1,600 μg/L, was estimated to be 105 kg. Whereas the factory was identified to be the major pollution sources of nonylphenolic compounds in the Kamo River, it was also found that gas stations and car washing stations widely distributed in the river basin were pollution sources. Moreover, it was suggested that the oligomer pattern of nonylphenolic compounds in an effluent reflected the situation of wastewater treatment of each business site.

A survey study for estrogens, nonylphenol (NP) and its precursors (nonylphenol ethoxylates and nonylphenol ethoxy acetates) was conducted for water and sediment of the Kamo River and its inflow waterways. 17β-estradiol (β-E2), estrone (E1) and 17α-estradiol were detected in river water and sediment up to the levels near their highest concentrations detected in the nationwide surveys. β-E2 concentration in water at almost all sampling sites was higher in winter and spring and lower in summer and autumn, suggesting more active decomposition of β-E2 by microorganisms at high water temperature. E1 showed the largest contribution to estrogenic activity of water among the examined compounds. However, NP accounted for a large part in estrogenic activity of sediment. The average emission loads of β-E2 and E1 estimated in the Kamo River basin were 12 and 75 nmol/cap/day, respectively. These values corresponded to a comparatively high amount estimated in the effluents from sewage treatment plants.

In this study, we analyzed over 30 types of PFCs, including precursors in both the dissolved phase and particle solid phase, in 50 samples of river water collected from throughout the Tokyo Bay basin. PFCs were detected in suspended solids (SSs) at levels ranging from −1 (0.11–2470 ng g −1 dry weight). The concentrations of PFCs in the SS were one to two order(s) of magnitude lower than those of PFCs in the dissolved phase. Relatively high levels of PFCs (total of 35 PFCs) in SS were observed in urbanized areas. The concentration of PFCAs, including PFOA and PFNA, were significantly correlated with the geographic index as artificial area ( R 2 of the linear regression curve in a double logarithmic plot: 0.09–0.55). Conversely, PFOS and FOSA were significantly correlated with the arterial traffic area ( R 2 in a double logarithmic plot: 0.29–0.55). Those spatial trends were similar to the trends in dissolved PFCs. We estimated the loading amount of PFCs into Tokyo Bay from six main rivers and found that more than 90% of the total PFCs reached Tokyo Bay in the dissolved phase. However, 40.0–83.5% of the long chain PFCAs (C12–C15), were transported as particle sorbed PFCs. Rain runoff events might increase the loading amount of PFCs in SS. Overall, the results presented herein indicate that greater attention should be given to PFCs, especially for longer chain PFCs in SS in addition to dissolved PFCs.

Pollution from 35 perfluorinated compounds (PFCs) in the water of the Tokyo Bay basin was examined. The water in the basin contained relatively high levels of perfluorononanoate (PFNA), perfluorooctanoate (PFOA), and perfluorooctane sulfonate (PFOS) compared to the other PFCs, which were present at concentrations of 20.1 ng/L, 6.7 ng/L, and 5.8 ng/L, respectively. In contrast, the concentrations of their precursors and degradation products were an order of magnitude lower. Sewage treatment plant (STP) effluent in the area also contained high levels of PFNA compared with the river water samples (Mann-Whitney U-test, p0.0002). From a spatial aspect, increases in PFC pollution levels correlated with increased urbanization in the study area suggested that there are nonpoint source contributors to the PFC pollution in this area. Branched isomers of the PFCs were also quantified. Samples that contained high concentrations of perfluoroalkyl carboxylates (PFCA) showed lower proportions of its branched isomer. This indicates that the branched isomers are more prominent in the area with lower PFC pollution. This analysis was beneficial for estimating the individual contributions of different PFCA production processes. This survey provided new information on the sources, spatial distribution, and behavioral characteristics of PFC pollutants in this area.

The concentrations of nonylphenol (NP), nonylphenol ethoxylates (NPnEOs: n = 1-15) and nonylphenoxy acetic acids (NPmECs: m = 1-10) in river water and sediment were determined seasonally at four sampling sites in the Kamo River, which is a typical urban river and was already known to be polluted by NP. In the water, the concentrations of NP, NPnEOs and NPmECs ranged from 0.13 to 3.65 microg/L, from 1.0 to 22.4 microg/L, and from 0.6 to 8.5 microg/L, respectively. NP, nonylphenol monoethoxylate (NP1EO), nonylphenol diethoxylate (NP2EO), nonylphenoxy acetic acid (NP1EC) and nonylphenol monoethoxy acetic acid (NP2EC) were predominant in the water. In the sediment, the concentrations of NP, NPnEOs and NPmECs ranged from 69 to 10,747 microg/kg dry weight (dw), from 74 to 6,101 microg/kg dw, and from 24 to 673 microg/kg dw, respectively. NP, NP1EO and NP2EO were predominant in the sediment. The total concentrations of NP, NPnEOs and NPmECs in both river water and sediment were higher in winter and spring than in summer and autumn. In the river water, the ratio in concentration of the sum of NP, NP1EO, NP2EO, NP1EC and NP2EC to the whole nonylphenolic compounds was correlated with water temperature. The surveyed results suggested that some point emission sources of nonylphenolic compounds were located in the river basin between the first sampling site and the second sampling site.