Lime plaster is renowned for its hygroscopic capacity, ability to capture formaldehyde and other volatile organic compounds (VOCs), and antimicrobial properties. However, these properties are primarily documented in studies on thick plaster used in traditional buildings, with limited data on the thin applications used in modern housing. Furthermore, information on the fungal resistance of lime plaster is scarce despite the significant health risks posed by indoor fungi, such as allergies. This study investigates the fungal resistance of thinly applied "modern lime plaster" and its varying effectiveness against different fungal species. Fungal resistance tests were conducted on lime plaster samples with different concentrations of slaked lime, using Aspergillus niger and Cladosporium sphaerospermum as test organisms. The findings indicate that "modern lime plaster" exhibited high alkalinity and exerted strong fungal resistance despite its thinner application than traditional lime plaster. In particular, formulations containing over 30% slaked lime effectively inhibited fungal growth. Additionally, the antifungal efficacy was greater against A. niger than C. sphaerospermum, reflecting differences in alkaline tolerance among fungal species. Therefore, lime plaster is a highly effective wall material with inherent fungal resistance, and may contribute to residents’ health through improve indoor air quality.

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Recently, the odor of scented products, such as cosmetics and detergents, has been frequently concerned as a factor in the onset and development of multiple chemical sensitivity (MCS). The experiences and memories exposed to those products may influence the olfactory perception of patients with MCS. Here, we conducted an olfactory test in seven patients with MCS and seven controls to clarify the effects of odor identification performance and type notification on odor evaluation for olfactory perception characteristics of patients with MCS. There was no difference in odor intensity of the presented odors between patients with MCS and controls. However, if comparing with and without odor type notification, odor intensity tended to be higher with the notification than that without the notification. Regarding the hedonic scales of the presented odors, patients with MCS showed more unpleasant than controls. For odor type notification, the hedonic scale was changed to pleasant side in four and two odors presented to the patients with MCS and controls, respectively. Changes to the unpleasant side were observed in one odor presented to the patients with MCS and three odors in controls. The changed odor types were different between patients with MCS and controls. Although no significant difference was observed in the number of correct answers for the twelve types of odors in the odor identification test, the number of correct answers was higher in controls than in patients with MCS.

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To improve comfort, research is being conducted from various perspectives such as heat, light, and sound. One of the factors that should be considered to achieve even higher levels of comfort is individual differences, such as sensitivity to heat or cold. Individual differences are a particularly problematic factor in environments where many individuals exist, such as in offices. By clarifying individual differences in how individual comfort is determined, we can contribute to the challenge of creating comfortable spaces for individuals. In this study, we clarified the cognitive structure of comfort in the office and remote work using a questionnaire survey, evaluation grid method, and experience sampling method. Although thermal factors have a large influence on subjective comfort in the office and remote work, it has been suggested that factors other than thermal factors such as humidity, light, sound, and internal factors also have an influence. Additionally, cluster analysis revealed that individuals can be classified into three types based on the degree of influence "inside type", "balanced type", and "thermal type". The existence of this individual difference indicates that factors that increase comfort differ depending on the individual. The preliminary experiment and the main experiment with a larger sample size in office work demonstrated the robustness of these results. Similar trends were observed at remote work. Therefore, it was suggested that the obtained results are applicable to a wide range of work environments.

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We measured an indoor formaldehyde (HCHO) concentration in Sendai-around area using a passive analytical chip combining a porous glass and β-diketone, during the summer and the winter in 2023. The average temperature in 2023 summer was 2 °C higher than that for the past 10 years. The HCHO concentration was calculated both from the absorbance changes at 414 nm of the analytical chip before and after exposure to an indoor air and from exposure time. In the measurements, HCHO concentration and questionnaire results were obtained from 142 and 144 rooms and the obtained HCHO average concentration was 37 ppb and 19 ppb in summer and winter, respectively. Room temperature has a large contribution to HCHO concentration, and the measurement results showed that the concentration increases 1.09 times for a 1 °C increase in temperature. It was also found that opening the windows was the most effective way to reduce HCHO concentration of the indoor air, and in the case of condominium, opening the windows for 30 minutes was estimated to reduce the HCHO concentration by 60%. We also have measured the adsorption ability of the materials, such as a wallpaper, igusa sheet for tatami, and diatomaceous earth, which were used in construction of house. The best adsorption performance was obtained for diatomaceous earth and it was 23.0 ng/g in 1 L of air with 160 ppb of formaldehyde. Although the indoor concentration of HCHO tends to be lower, the summer temperature will be higher than we have never experienced, and the indoor concentration of HCHO assumed to be higher, therefore to check indoor air condition become more important. In that case, the developed analytical chip is expected to function effectively.

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