We have developed an analytical method fbr trace amount of carbonyls in indoors and ourdoors. This method consists of sampling of carbonyls with passive sampler, solvent extraction, HPLC/spectrometer with large-volume-injection method. The method detection limits of 6 detected carbonyls(Formaldehyde, Acetaldehyde, Acetone, Propionaldehyde, Benzaldehyde, n-Hexanal)were 0.001-0.007μg/m³. We have also determined indoor and outdoor concentration of carbonyls using developed method. Sampling locations were 22 and 21 public facilities including libraries and schools, in 2005 and 2006, respectively. Forty one houses were also investigated. The six carbonyls were detected in this study. Formaldehyde concentrations of 11 out of 294 sampling points in the public facilities exceeded the indoor air quality guideline(100μg/m³)of Ministry of Health, Labour and Welfare, Japan. These of 13 out of 397 sampling points in the households exceeded the guideline. Acetaldehyde concentration of 19 out of 397 sampling points in the households exceeded the indoor air quality guideline(48μg/m³) of Ministry of Health, Labour and Welfare, Japan. In the public facilities, formaldehyde concentrations in winter is significantly lower than those in summer, but in households those in winter is not so much lower than those in summer. This is mainly because indoor temperatures in households were high in night time. No correlation between fbmlaldehyde and other aldehydes concentrations were found, but significant correlations were fbund among acetaldehyde, acetone and hexanal concentratlons.

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In modem living environments, humans are exposed to numerous types of pollutants in indoor air. However, secondary emission products generated through chemical reactions have not been fully concerned in relation to so-called Sick House Syndrome. In this study, we focused on formic acid suspected to have impact on human health such as chemical sensitivity due to its low irritant level. Gas to particle conversion is a possible way of decay of gaseous formic acid in indoor air due to lower vapor pressure of formate. Then, authors have developed a sampling apparatus, by serially connecting miniature diffusion scrubber, impinger and air pump, for the determination of gas-particle distribution of formic acid in indoor air. Ion chromatography was employed for the analysis of formate ion trapped in the aqueous potassium hydroxide in each sampling device. The collection efficiency of the gaseous formic acid by the first stage scrubber was 94% without back-diffusion of trapped formic acid and sink of particles in the scrubber. Collection amount of formate species by this system was equivalent to that by a previous impinger method. Field measurements were conducted at occupied houses. The results showed the formic acid was firstly generated as gaseous form and gradually changed to particulate form with time in indoor air of the houses. However, the conversion mechanism was still unknown, because the gas-particle ratio was not consistent by the day even in the same house.

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A questionnaire was used to survey schoolchildren (6-12 years of age) in Joetsu City for multiple chemical sensitivity-like symptoms (MCS-like symptoms), allergies and particularly offensive odor. The city has a school-age population of 12,045 children. The number of collected questionnaires was 10,348, representing 85.9% of the total number of schoolchildren. The children's parents or guardians were asked about the symptoms exhibited their children. The questionnaire was based on the MCS criteria for diagnosis adopted by the Allergy Committee of the Japanese Ministry of Health, Labour and Welfare (MHLW). The questionnaire included 14 items from the MCS criteria. The number of schoolchildren with MCS-like symptoms was 979 (9.5%) in the total survey population of 10,348 schoolchildren. The rate of pollinosis was 19.3%, allergy (including pollinosis) was 47.6% and particularly offensive odor was 32.7%.
MCS is considered different from the immunological mechanisms of an allergy. The schoolchildren with MCS-like symptoms, however, had many allergies at a rate of 63.7%. Schoolchildren who had not been selected as exhibiting MCS-like symptoms had an allergy rate of 46.3%. The difference in the allergy rate between the two groups of schoolchildren was significant. In addition, many schoolchildren with MCS-like symptoms had a particularly offensive odor at a rate of 60.5%. Schoolchildren who had not been selected as exhibiting MCS-like symptoms had a particularly offensive odor rate of 30.6%. Similarly, the difference in the particularly offensive odor rate between the two groups of schoolchildren was significant.
As age increased, the ratio of schoolchildren with MCS-like symptoms, allergies and particularly offensive odor increased. The results suggest that older schoolchildren were more sensitive to chemicals.

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The guideline concentrations of chemical compounds in the indoor environment were established in 2000 by the Ministry of Health, Labour, and Welfare, and their standard values were established in 2002 by the Ministry of Land, Infrastructure and Transport. Consequently, use of the controlled substances was prohibited, and various substituting nonregulated substances have been used.
To examine the status of concentrations of volatile organic compounds (VOC) in the indoor environment, the detection rates and concentration distributions of 6 controlled substances and 16 nonregulated substances (total, 22 substances) were examined in 3,039 institutions from December 2002 to March 2007. It was found that the detection rates of 1-butanol, trichloroethylene, trimethylbenzene, and decane were significantly increased after revision of the building standard law in 2003. When the total detectable amount of the 22 materials examined in this study was regarded as the total volatile organic compounds (TVOC), the maximal TVOC concentration of TVOC was 54,266μg/m³,the mean was 1,005 μg/m³, and the median was 215 μg/m³. In 39% of the samples, the TVOC concentration was higher than 400 μg/m³, which is the target value established by the Ministry of Health, Labour, and Welfare.

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On July 5, 2005, samples of airborne fungi growing in the house of a patient with pulmonary aspergillosis in Nagasaki city, Nagasaki prefecture were taken for investigation. Sampling of the airborne fungi was conducted by using an air sampler (SAS SUPER 100, PBI) in the living room of the first floor and the bedroom of the second floor. Samples from ten places in each room were taken using a DG-18 medium (100L suck).
As a result, the mean value of the airborne fungi density was 634±100.6 CFU/m³ in the living room, and 1220±1853.9 CFU/m³ in the bedroom. Both Cladosporium and Mycelia sterilia accounted for about 70% of the fungi in the living room as a result of identifying isolates, while in the bedroom about 70% of the fungi was Aspergillus. Moreover, the ratio of Aspergillus in which A. fumigatus was the causal fungi of pulmonary aspergillosis was close to 100%. These figures suggest that the resident is inhaling A. fumigatus on a daily basis.

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The evaluation tests on removing performance of airborne microbes were tried with a commercially available air cleaner. A simplified examination room with negative air-pressure was assembled in a room in a laboratory. The spores of fungi, Wallemia sebi or Penicillium glabrum, were spread in the examination room. An aerial ultrasound method was adopted for the spray. The spores floating in the air were trapped using gelatin filters, and the concentrations of viable spores in the air were measured. The time-lapse remaining rates of viable spores in the air were obtained at different operating conditions of a tested air cleaner, no operation, operation without ion emission, and operation with ion emission. Although the decreasing effect of airborne microbes by the filter of the cleaner was detected, the decreasing effect by the emission of ions at the air cleaner was not detected.

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Growth of molds in buildings can invade occupants tissue and cause infection. It is important to know the cases of mold contaminations in order to think about measures. In this report, some cases on mold problems are introduced. The information sources are internet web site of U.S.A.

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