Fate estimation of estrogenic substances in an urban river by flux calculation.

This study investigated the fate of estrogenic substances in an urban river receiving discharge from wastewater treatment plants (WTPs) by flux calculation, focusing on the middle reaches of the Tama River in Tokyo, which is one of the most urbanized rivers in Japan. The level of estrogenic activity flux was almost negligibly small at the upstream station. The level was considerably raised after inflows from the WTPs and then the level declined in the lower reaches of the river. When contributions of estrogenic substances to estrogenic activity were estimated, estrone (E1) was the primary contributor to the total estrogenic activity in all the sampling stations, followed by estradiol (E2). The contribution of nonylphenol to estrogenic activity was small. The E1 and E2 accounted for approximately 90% or more of estrogenic activity in the Tama River. As for the total fluxes of the estrogenic substances in the study area in the Tama River, the proportion of flux associated with WTP discharge was approximately 100% of the total fluxes, and the effects of the tributaries flowing into the river were almost negligible. When the reduction ratios of estrogenic activity were calculated by the flux, the ratios were found to increase toward the lower reaches of the river. Similar changes were observed for E1. Meanwhile, the change of reduction ratios for E2 was different from that observed for estrogenic activity.     

Utilization of regenerated iron oxide for treatment of organotin compounds in seawater

We examined the removal and degradation efficiencies of regenerated amorphous iron oxide on tributyltin (TBT) and triphenyltin (TPT) in seawater. It was confirmed that following contact with iron oxide at 20 and 60?°C, the half-lives of TBT and TPT were shortened. These half-lives were from one-thousandth to one-tenth for natural environment conditions. Dibutyltin and benzene were identified as the reaction products from TBT and TPT, respectively, indicating that the degradation pathways were mainly dealkylation and dephenylation. These results indicate that the treatment method by natural energy will enable the economical and rapid reduction of organotin compounds (OTCs). For OTCs in seawater will be adsorbed on the iron oxide by the ebb and flow of the tide and solar energy will be heat source for degradation when iron oxide is prepared in coastal locations.     

Variation in estrogenic activity among fractions of a commercial nonylphenol by high performance liquid chromatography

Estrogenic activity by recombinant yeast screen assay of the commercial NP was considerably higher when compared with that of n-nonylphenol (n-NP). Fractionation of the commercial NP by high performance liquid chromatography (HPLC) afforded seven isomers: 4-(1,3-dimethyl-1-propyl-butyl)-phenol, 4-(1,1,3-trimethyl-hexyl)-phenol, 4-(1,1-dimethyl-3-ethyl-pentyl)-phenol, 4-(1,1,4-trimethyl-hexyl)-phenol, 4-(1-methyl-1-propyl-pentyl)-phenol, 4-(1,1,2-trimethyl-hexyl)-phenol and 4-(1-ethyl-1-methyl-hexyl)-phenol. The structures of these isomers were determined by GC-MS and nuclear magnetic resonance spectroscopy (NMR). All of these isomers possessed tertiary alpha-carbon in their chemical structures. Another tertiary NP, 4-(1,1-dimethyl-heptyl)-phenol was synthesized in the present study and this synthetic NP also exhibited the estrogenic activity. One fractionated compound was identified as one of decylphenol, 4-(1-ethyl-1,4,4-trimethyl-pentyl)-phenol. The isomer, 4-(1,1,4-trimethyl-hexyl)-phenol exhibited the highest estrogenic activity corresponding to 1/10000 that of 17beta-estradiol (E2). The activity of n-NP was the least. This suggests that it may be possible to develop a technical NP mixture with relatively low estrogenic activity.     

Sources of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and coplanar polychlorinated biphenyls (Co-PCBs), and their bioaccumulation through the marine food web in Sendai Bay,Japan

The concentrations of PCDD/F and Co-PCB congeners in seawater, sediment, Pacific oyster, Japanese anchovy, marbled sole, and Japanese flounder samples from Sendai Bay, Japan, were analyzed. The compositions of total PCDD/F and total Co-PCB concentrations in sediment and Pacific oyster reflected that in seawater--the compositions of total PCDD, PCDF, and Co-PCB concentrations were approximately 60, 10, and 30%, respectively. The compositions in Japanese anchovy, marbled sole, and Japanese flounder were different from those in seawater and sediment-the ratio of total Co-PCB concentration to total PCDD/F plus Co-PCB concentrations in Japanese anchovy, marbled sole, and Japanese flounder was above 90%. Tetrachlorinated PCDDs (T4CDDs), such as 1,3,6,8- and 1,3,7,9-T4CDD, were the predominant congeners in seawater and sediment; the total T4CDD concentrations in seawater and sediment were approximately 46 and 48% of the total PCDD concentration. Furthermore, shipments of the herbicide 1,3,5-trichloro-2-(4-nitrophenoxy)benzene to Miyagi Prefecture, the so-called granary of Japan, were the highest in Japan over the last 12 years. The major sources of PCDD/Fs and Co-PCBs in Sendai Bay, which is in Miyagi Prefecture, are impurities in chlorinated herbicides. The order of concentration of PCDD/Fs was Pacific oyster > Japanese anchovy = marbled sole > Japanese flounder; the concentration in Japanese flounder, which is a higher-trophic-level consumer in the marine food web, was lower than that in shellfish (Pacific oyster) and Japanese anchovy, which are lower-trophic-level consumers. The order of concentration of Co-PCBs was Pacific oyster < Japanese anchovy = marbled sole < Japanese flounder; the concentrations in the higher-trophic-level consumers were higher than the concentrations in the lower-trophic-level consumers. Different PCDD/F congeners tended to bioaccumulate in different organisms. On the other hand, all species of Co-PCB congener tended to bioaccumulate in all organisms.     

Evaluation of Virus Reduction by Ultrafiltration with Coagulation–Sedimentation in Water Reclamation

The evaluation of virus reduction in water reclamation processes is essential for proper assessment and management of the risk of infection by enteric viruses. Ultrafiltration (UF) with coagulation–sedimentation (CS) is potentially effective for efficient virus removal. However, its performance at removing indigenous viruses has not been evaluated. In this study, we evaluated the reduction of indigenous viruses by UF with and without CS in a pilot-scale water reclamation plant in Okinawa, Japan, by measuring the concentration of viruses using the real-time polymerase chain reaction (qPCR). Aichi virus (AiV) and pepper mild mottle virus (PMMoV) were targeted in addition to the main enteric viruses of concern for risk management, namely, norovirus (NoV) genogroups I and II (GI and GII) and rotavirus (RoV). PMMoV, which is a plant pathogenic virus and is present at high concentrations in water contaminated by human feces, has been suggested as a useful viral indicator. We also investigated the reduction of a spiked model virus (F-specific RNA bacteriophage MS2) to measure the effect of viral inactivation by both qPCR and plaque assay. Efficiencies of removal of NoV GI, NoV GII, RoV, and AiV by UF with and without CS were >0.5 to 3.7 log₁₀, although concentrations were below the detection limit in permeate water. PMMoV was the most prevalent virus in both feed and permeate water following UF, but CS pretreatment could not significantly improve its removal efficiency (mean removal efficiency: UF, 3.1 log₁₀; CS + UF, 3.4 log₁₀; t test, P > 0.05). CS increased the mean removal efficiency of spiked MS2 by only 0.3 log₁₀ by qPCR (t-test, P > 0.05), but by 2.8 log₁₀ by plaque assay (t-test, P < 0.01). This difference indicates that the virus was inactivated during CS + UF. Our results suggest that PMMoV could be used as an indicator of removal efficiency in water reclamation processes, but cultural assay is essential to understanding viral fate.     

Effect of Manufacturing Process and Xanthan Gum Addition on the Properties of Cassava Starch Films

The objective of this work was to manufacture biodegradable films by two different processes (casting and extrusion), from different combinations of cassava starch and xanthan gum. These films were produced by casting and by extrusion from six different starch-xanthan gum combinations (0, 2, 4, 6, 8 and 10% w/w), containing glycerol as plasticizer (20% w/w) and were also characterized according to their microstructure, optical, mechanical, and barrier properties. Scanning electron microscopy of the starch-xanthan gum extruded films showed reticulated surface and smooth interior, suggesting that xanthan was driven to the surface and gelatinized starch to the interior of the films during extrusion. Films manufactured by casting were entirely homogeneous. In general, casted films presented lower opacity and water vapor permeability and higher stress at break than films manufactured by extrusion. Xanthan gum addition affected mechanical properties of starch films, improving their stress and strain at break, especially for extruded samples, but these properties did not show stability at different RH conditions.     

Optimization of separation and logistics for recycling materials from wallpaper hanging sites

It is of huge importance for sustainability to find a pragmatic solution for recycling of a variety of wastes emitted in small mass such as the case of wallpaper replacements. A combination of two-step sorting scheme and transportation of the wastes in collaboration with the wholesalers was proposed to enhance the efficiency of recycling. The two-step sorting consists of the first sorting at the wallpaper hanging sites to separate and group wastes in a way to avoid heavy additional burden on the hanging job. Secondary sorting is conducted at a Sorting Center to re-group wastes to send to an intermediate processing company for recycling. To minimize the costs for transportation, the grouped wastes emitted at the hanging sites are brought back by the hangers and kept temporally and then moved to the wholesaler(s) on the way to receive new materials. When the wastes at the wholesaler(s) become sufficiently large for economic transportation, a truck is arranged to collect the wastes to transport them to the Sorting Center. A feasibility study to test the practicality of the method confirmed that it could be operable and the cost would be comparable or lower than that currently incurred for disposal of the wastes.     

Development of extraction method of pharmaceuticals and their occurrences found in Japanese wastewater treatment plants

In this study, occurrence of 66 PPCPs (pharmaceuticals and personal care products) in liquid and solid phases of sewage sludge was elucidated. The extraction methods for the PPCPs from sludge were newly developed employing Pressurized Liquid Extraction (PLE) and Ultrasonic Solvent Extraction (USE). As an appropriate method, PLE using water (pH2), PLE using methanol (pH4), and USE using mixture of methanol and water (1/9,v/v, pH11) was found most effective because total recovery of most of the PPCPs indicated 40 to 130%. The developed extraction method with previously developed method for liquid phase analysis was applied to field survey at wastewater treatment plants (WWTPs) in Japan. 56 compounds were detected from the primary sludge and 61 compounds were detected from the excess sludge. The concentration was ranged between several ng/g and several μg/g. Solid-water distribution coefficient (Log K_d) ranged between 0.9 L/kg (Caffeine) and 3.7 L/kg (Levofloxacin) for primary sludge and between 1.4 L/kg (Sulpirid) and 4.3 L/kg (Mefenamic acid) for excess sludge.