2,2,4-Trimethyl-1,3-pentanediol monoisobutyrate (TMPD-MB, typical product name: Texanol) and 2,2,4-trimethyl-1,3-pentanediol diisobutyrate (TMPD-DB, typical product name: TXIB) are mainly used as a surface stabilizer for water-based paints and adhesives and as a plasticizer, respectively. They are compounds for which the Ministry of Health, Labour and Welfare in Japan is considering formulating guideline values for indoor air concentrations. It has been reported domestically and internationally that these compounds are associated with sick building syndrome and allergic diseases. Knowledge concerning the amounts of these compounds taken into the body is very important in order to prevent the adverse health effects by exposure to them on general population in living environments, but there is almost no information available.
In the present study, Japanese 132 children (6 to 15 years old) who were more vulnerable to the effects of chemicals than adults were targeted, and the intake of these compounds through all exposure pathways at home was estimated by measuring their urinary metabolites. The metabolites were found in all of the subjects' urine, suggesting that internal contamination with these compounds was widespread among Japanese children. The daily intake per body weight as TMPD-MB or TMPD-DB was estimated to be approximately 1 μg/kg b.w. as median, and 10 μg/kg b.w. as maximum assuming that the children were at home all day. This was at the same level as those for p-dichlorobenzene, naphthalene and several phthalates in the children at home.
The results of this study can be used as useful data for the future researches on exposure-effect assessment and for administrative measures to prevent adverse health hazards by exposure to these compounds.

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Since children have immature bodily functions, they may be more susceptible to damage from chemical exposure accidents than adults. In this study, we investigated accidents related to indoor chemical exposure in children using major domestic product accident databases and tried to classify them using the National Electronic Injury Surveillance System codes. In body parts, it was found that the parts of head and neck was the highest fraction of 33.8% of injuries in 0–19 age group. As for the type of injury, the most common type of injury was the skin disorder, including dermatitis and chemical burns, and the fraction was 61.1% in 0–19 age group. Besides, it was found that the product fields with many accidents were cosmetics and pharmaceuticals, architecture and furniture, and toys. Additionally, the estimate incidence for poisoning, dermatitis, and chemical burns for 0–19 age group, related to the extracted product codes, were approximately in the range of 1E-6 to 1E-5 (incidence / population / year). The expected risk values were generally in the range of 1E-11–1E-10 (lost-years per person / year), with no significant differences among diagnosis and product codes. A comparison of each age group showed that the codes related to toys and fabric treatment products for poisoning had 15 times and 9 times higher incidence and 6 times and 3 times higher expected risk values in the 1–4 age group, than those for all age group. This indicated that this age group and the corresponding diagnosis/product codes are of higher risk in indoor chemical exposure accidents.

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We focused on amphiphilic polymers that have both a hydrophilic region (dimethylaminoethyl methacrylate, DAM) and a hydrophobic region (ethyl methacrylate, EMA). We synthesized a new functional polymer with a ratio of 60:40 and investigated its antifungal effect against Aspergillus brasiliensis, Cladosporium cladosporioides, and Fusarium oxysporum. In the mycelial growth inhibition test, low concentrations of the polymer were highly effective against all molds tested, and the minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) against A. brasiliensis were both 1.25 wt%. These results revealed that this polymer is effective as a fungicidal agent. Furthermore, as a result of observing the effect of polymer addition on hyphal growth using slide culture, it was observed that the formation of conidial heads and septa was inhibited, and furthermore, the amount of ergosterol was increased. Therefore, it was inferred that excessive synthesis or accumulation of ergosterol causes inhibition of hyphal elongation and conidia formation. Based on the above, this polymer may have a new mechanism of action that is not an ergosterol inhibitor, and the possibility of its use as a novel antifungal agent that can be applied to indoor environments has increased.

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We measured permeation degrees of three different types of respirators by using an original testing system. The first type of respirator is a non-woven mask constructed from three layers of one thick non-woven fabric sandwiched by two thin non-woven fabric and bacteriophage permeation degree is 10 percent. Second, particulate respirator (N95) does not permeate any of bacteriophage. Lasty, its permeation degree of the gauze mask layered 9 of double sheet gauzes is 56 percent. Everything of these respirators hesitated comfortable breathing. The respirator comfortable breathing and preventable permeation of virus is hoped in the future. We used four different kinds of activated carbons and each charcoal crushed after carbonizing five kinds of woods to analyze materials that works effectively for bacteriophage capturing. The high capturing percentages were showed in an activated carbon and in each crushed charcoal of particle size of 0.1-0.3 mm carbonized Japanese cedar, Pine or Japanese oak. The reason why the higher capturing effectiveness was gained in these crushed charcoals was estimated by measuring of the pore volume and specific surface area with the big size, and the specific construction of the particle surface by the scanning electron microscope (SEM) pictures. Especially, the 0.1-0.3 mm size charcoal of Japanese cedar is light-weight, and will produce superior effectiveness of the capturing in small volume, the 5 mm layer of the material in the holder could maintain highly the capturing percentage in long time test of capturing too. The same charcoal of 0.1-0.3 mm size will be used for virus capturing material for the new type mask.

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