Numerous studies on ethylene and odors in household refrigerators have been presented, whilst few were reported on the airborne carbonyl compounds. The carbonyl compounds in household refrigerators may have possible impacts on human health and food freshness, because some of them are known to cause adverse health effects and to inhibit enzyme activity in vegetables. In this study, authors have attempted to determine the concentrations of carbonyl compounds in air of domestic refrigerators by using a 2,4-dinitrophenylhydrazibe(DNPH)-active sampling-High Performance Liquid Chromatography(HPLC) system. Air concentrations of six carbonyls, including formaldehyde, acetaldehyde, acetone, acrolein, propionaldehyde and butyladehyde, were determined for practically occupied refrigerator and vegetable rooms (n = 15). The higher level was found in the acetaldehyde concentrations ranging from 14 to 150μg/m³ with a mean of 59μg/m³, slightly greater than the Indoor Air Guideline in Japan. The air concentrations in refrigerators were then compared with those in indoor air of rooms where the refrigerators were practically placed. The comparison showed emission sources of acetaldehyde, acetone and acrolein might exist inside the refrigerators. To investigate the factors influencing these concentrations, a partitional clustering of 15 rooms were conducted using room volume, frequency of opening the door, temperature, number of occupants and contents (food and beverage) as variables. The cluster analysis showed the air concentrations of acetaldehyde and acrolein in refrigerators were mostly influenced by number of occupants and stored contents.

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An investigation of formaldehyde, VOC and SVOC was performed in both new and old apartment houses both before and after revision of Building Standard Law of Japan to examine a relation between them and aging changes, climate, air change rate and sampling condition. These results were considered gather with that in a pilot house from viewpoints which contributes to improvement of indoor air quality. Temperature/humidity characteristics of formaldehyde concentration, concentration decrease characteristics of each VOC species, evaluation of α -Pinene from wood-based materials and an evaluation method of TVOC were considered. Sampling condition of formaldehyde and reduction in amounts of tick pill used for tatami were proposed. Practical characteristics of a sanitary ventilator and the effect of sampling timing after window-shut on the measurement value of concentration were considered. Formaldehyde concentrations in resident houses were compared with that in nonresident house, and the influence to the formaldehyde concentration of the thermal condition was made clear to measure air of the top, middle and first floor in some multistory apartment houses.

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This study was carried out as a part of a project to identify the source(s) of Pb in indoor dust in dwellings in Japan. Because of unique features with regard to Pb in Japan - early phase-out of leaded gasoline and no tradition of painting the interior/exterior of houses - Japanese houses lack the definite Pb contamination sources (paint and leaded gasoline) that are known to occur in other developed countries. Indoor dust, outdoor dust and soil samples were collected from 41 households in Japan and Pb and Cd concentrations in the samples (<250 μm fraction) were measured by ICP mass spectrometry after HNO₃/HC1O₄/HF digestion. Median concentrations of Pb and Cd were 54.1 and 0.932 mg/kg, 31.7 and 0.563 mg/kg, and 153 and 1.74 mg/kg for indoor dust, soil and outdoor dust, respectively. The concentrations of Pb and Cd in indoor dust were lower than those previously and currently reported, indicating that dwellings in Japan are less contaminated with these metals than are those in other countries. Indoor dust Pb and Cd concentrations were only weakly correlated with outdoor metal concentrations and did not correlate with household variables (household type, presence/absence of smoker or pet, heating fuel and type of flooring). The results indicated that there were unknown factors that affect indoor dust metal concentrations in Japanese households.

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In response to heightened awareness of protecting the health of infants and fetuses, as shown by the Miami Declaration adopted in 1997 and the Dubai Declaration in 2006, various actions have been taken. The effect of exposure to toluene, which is a typical indoor air contaminant, on the cerebral nervous system of humans during development is now being studied, in addition to its well-known toxicity. When investigating the effects of volatile organic compounds such as toluene, it is essential to examine their dynamic behavior in the human body as well as their toxicity. However, such research on fetuses and newborns requires a simple method applicable to micro-samples. The solid phase micro extraction (SPME) method is one such technique and is effective. Detailed susceptibility studies on the vulnerability of immature individuals must be conducted in the future.

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It is well known that one third of the Japanese is suffered from a certain allergy. There are various things related to the allergen which is the causative agent of allergy, and mold is one kind of important allergen in indoor environment. Although it is necessary to reduce contamination by mold, since the“dose-response relationship”of almost all molds is unknown, it is actually difficult to enact the environmental standards about indoor mold based on healthy influence or risk assessment method.
In the first half of this paper the healthy influence and risk of human by mold and the establishment method of environmental standards based on dose-response relationship were introduced. In the second half, present conditions of the environmental standards on mold were described.

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First, basic knowledge of light and vision, photometry, history of daylighting and artificial lighting are shown in this article. Second, lighting requirements for indoor environment are described based on the parameters which are specified in JIS Z 9125“Lighting of Indoor Work Places”. Luminance distribution, illuminance, glare, directionality of light, color of light and color rendering are included. Moreover, daylight in indoor environment is discussed regarding change in its amount, spectral distribution, effect of direct sun light and psychological effects of daylight and windows. Finally“light and Low-carbon society”and“light and health”are presented. The effect of several strategies to reduce CO₂ emission due to indoor lighting is simulated, e. g. if all incandescent lamps are replaced by LED, reduction of CO₂ emission can reach 4 million ton which equals a target value. As health effect of light, suppression of melatonin secretion, which shows a circadian rhythm, by light was also discussed.

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Active samplers, passive samplers and dositube (gas detecting tube) are currently employed to measure indoor air pollutants such as VOCs and RCHO. It is, however, cumbersome for researchers to find out the most suitable method for capturing the air pollutants because of diverse nature of the pollutants and the sampling sites. In this study, a questionnaire survey intended for Japanese research institutes was conducted to investigate the status of use for the methods of air sampling, the reasons for the selection and the sampling frequency of the passive samplers. The questionnaire was sent to 175 institutions including local public institutions and the pharmaceutical association testing centers. The number of respondents of those surveyed was 135 (95 of the public institutions and 40 of the pharmaceutical association testing centers). Our analysis of the answers from the respondents revealed that the passive samplers could have the advantage of“simpler operation”over the active sampling methods, although the latter methods could have higher“analytical precision”and“reliability”when compared to the former. In addition, it was found that air pollutant chemicals were measured by the passive samplers only when those SR values were cited in the respective passive sampler manuals. Thus, it is recommended that information about the advantage of the passive samplers and the SR values of additional chemicals be provided in order to encourage broad use of the passive samplers.

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