Many studies on pharmaceuticals in the environment have recently been conducted in Japan. However, there are few studies on synthetic fragrance materials and organic UV filters in the environment in Japan. They are widely used compounds in many personal care products, and are categorized as pharmaceuticals and personal care products (PPCPs) pollutants in America and European countries. Synthetic fragrance materials and organic UV filters are groups of structurally diverse chemicals whose physical and chemical properties are very broad and differ from many pharmaceuticals in terms of having characteristics such as a higher volatilization level and a higher hydrophobicity. Adding to that, there is no official database of the production or consumption amount of each chemical. In this review, we provide fundamental data of synthetic fragrance materials and organic UV filters and their national market volume estimated in Japan and also summarize and discuss the concentrations of such compounds in the environment, human and ecological risk assessment and problems for further study in Japan.

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The terrestrial plant Luffa cylindrica was applied to a surface-flow-constructed wetland (SFCW) to treat effluent from rice fields. To control the excessive growth of weeds that interfere with the maintenance of SFCWs, SFCWs with and without shading were constructed and the effect of shading was investigated. The average removal efficiencies of T-N and T-P for 135 day operation of the SFCW with shading were 57 and 53%, respectively, while in the case of those without shading were 44 and 41%, respectively. This result indicates that the nutrient removal efficiency was stimulated by shading. Although L. cylindrica completely dominated the SFCW with shading, the total plant biomass production including weeds was higher without shading. The total length of the roots in the SFCW with shading was, however, 2.2-fold that without shading. Consequently, it was suggested that the longer root length observed in SFCW with shading promoted the sedimentation of nutrients, resulting in a nutrient removal efficiency higher than that in the case without shading. These results demonstrate that shading is effective not only to control the growth of weeds but also to enhance the growth of roots in SFCWs, resulting in easier maintenance and a higher nutrient removal efficiency.

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The numbers of ammonia-oxidizing bacteria (AOB), Nitrospira and Nitrobacter in a municipal wastewater treatment plant were examined for five months using a real-time PCR quantification technique. The numbers of AOB and Nitrospira were in the ranges of 3.8×10¹⁰-2.0×10¹¹ and 4.7×10¹⁰-1.6×10¹¹ cell · l^-1, respectively. Additionally, the fractional percentages against the number of eubacteria were in the ranges of 2.1-7.6 and 2.6-7.0 %, respectively. Nitrobacter was less than 1 % as common as Nitrospira. On the other hand, the maximum ammonia- and nitrite-oxidizing rates obtained from aerobic batch tests ranged from 0.08 to 0.41 and from 0.10 to 0.27 mmol-N · l^-1 · hr^-1, respectively. No correlation between cell number and maximum rate was observed. The maximum cell-specific ammonia- and nitrite-oxidizing rates were then estimated to be in the range of 0.53-5.6 and 1.2-5.4 fmol-N·cell^-1 · hr^-1, respectively. In other words, even in the same wastewater treatment plant, these maximum cell-specific rates were not unique. To explore the factors controlling the maximum cell-specific ammonia-oxidizing rate, the relationship with in situ ammonia-oxidizing activity per cell was investigated. A fairly good correlation was obtained. The result indicates that the amount of ammonia oxidized per cell controls the maximum cell-specific ammonia-oxidizing rate and is the primary contributor to the variation. Meanwhile, the maximum cell-specific nitrite-oxidizing rate responded to the increase in the maximum cell-specific ammonia-oxidizing rate when the number of Nitrospira was less than that of AOB.

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In this study, norovirus-binding proteins (NoVBPs) were newly recovered from activated sludge culture using affinity chromatography. The C-terminal amino acid sequence (12 residues) of the Lordsdale virus, belonging to the dominant genotype (GII.4) of noroviruses throughout the world, was used as a ligand in the affinity chromatography. Two-dimensional electrophoresis analysis shows that the samples recovered by the affinity chromatography include a variety of proteins, which have a molecular weights between 60 and 10 kDa and isoelectric points between 3 and 6. The binding affinity of NoVBPs to the virus-like particle (VLP) of norovirus GII.4 was higher than that to the VLP of norovirus GI.1, which was indicated by ELISA. A determination of the N-terminal amino acid sequences revealed that several NoVBPs are relatives to a chaperonine protein, GroEL, which can interact with denatured hydrophobic proteins. The NoVBPs recovered in this study might be useful as versatile adsorbents for norovirus recovery or detection from environmental water samples.

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