Formaldehyde solution is widely accepted as a liquid sterilizing agent for animal research and pharmaceutical facilities. After the fumigation by formaldehyde gas, the indoor air is contaminated by the residual gas at hundreds to thousands part-per-million, and hence the concentration levels should be reduced before evacuation into atmosphere to meet emission criteria. This study aimed to develop a novel air cleaning device for the removal of formaldehyde gas residue employing manganese dioxide as a major ingredient of the honey-comb air filter. A prototype device was tested in a full-scale and closed chamber (23 m³) with demonstrations of formalin fumigation. The results showed the device significantly decreased 500-3000 ppm of formaldehyde with a production of equimolar carbon dioxide in the chamber even at room temperature. Though the time courses of formaldehyde concentration depended on the initial concentration, levels of the residual gas decreased below the emission criteria within eight hours. These results suggested the possible use of this methodology for post-treatment of formalin fumigation.

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The standard measurement of formaldehyde in indoor air involves the use of a 2,4-DNPH cartridge collection and solvent extraction/HPLC. This method is adopted and widely used as the standard measuring method by WHO, U.S. EPA, and JIS. However, the reagent in this standard method has exhibited mutagenicity and carcinogenicity, and therefore, a new alternative method is now desired. In this study, a scavenger with 2,4-pentanedione impregnated silica gel, which was free of the harmfulness associated with the reagent, was produced, and it was used in an active sampler which filled the glass tube with this. Using this sampler, basic examination such as the following were carried out: collection efficiency test, determination of theoretical value and its comparison with the analytic value, the standard DNPH-based method carried out in residential environment, and relative measurement of this method of the extraction method. The results, show that the extraction method used the method for directly supplying the 2,4-pentanedione solution in the sampler. The repeatability in sampling formaldehyde gas of 0.03 ppm was 3.5 % in the relative standard deviation. Formaldehyde with a theoretical concentration of 0.066-0.190 ppm was produced using a polyester bag. The analytic measurement value obtained using this method, agreed within ±3.8% with the theoretical value. In addition, there was a significant correlation between the measured values obtained by simultaneous measurement using this and the standard DNPH-based methods, in residential environment. Thus, the practicability of this method was confirmed.

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In storerooms without air-conditioning or dehumidification systems, fungi tend to grow in summer, when the outdoor relative humidity is high enough for fungal growth in Japan. For the conservation of cultural assets in these storerooms, vapor-impermeable bags might be useful as containers. Nine kinds of test bags, which were heat-sealable, were prepared from different membrane materials commercially available. A fungal detector, that encapsulates spores of sensor fungi and nutrients, was put in each test bag and sealed up using a heat sealer for determination of a fungal index, which represents the environmental (climate) potential for fungal growth. Then, the test bag encapsulating the detector was exposed under a humid climate in a moisture chambers set at 25°C and 93.6% relative humidity. Fungal index was measured for evaluation of microclimates inside of each test bag after exposure of 2, 7, 14, 28, 56 or 182 days. The microclimates in the bags differed depending on the employed membrane materials. No growth of sensor fungi was observed even in 182-days exposure in the sealed bags of aluminum-laminated film (0.114 and 0.092 mm in thickness), and the fungal index values were less than 0.3. In contrast, the growth of sensor fungi was observed in 2-days exposure in the bag of polyethylene film (0.010 mm in thickness), and the fungal index value was more than 80. For this reason, the bag made of aluminum-laminated film is considered to be very useful for the conservation of cultural assets in the humid storerooms aforesaid. Fungal index must be a useful tool in the operation of IPM (Integrated Pest Management) at museums, libraries, and other buildings.

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A questionnaire survey was conducted of elementary school students (6-12 years of age) in Joetsu City for multiple chemical sensitivity-like symptoms (MCS-like symptoms) in July, 2005. In July, 2010, 5 years after the first survey, a resurvey of elementary and junior high school students (6-15 years of age) was carried out in order to assess any temporal changes. The number of valid responses was 14,024, representing 84.0% of the total number of students. The results showed that the number of students with MCS-like symptoms was 1,734 (12.4%) of the total number of resurvey respondents. The following results were highlighted: (1) The propotion of school students with MCS-like symptoms becomes greater with age. (2) The propotion of the total of elementary school students with MCS-like symptoms is greater than previously calculated. (3) Students from the third grade of elementary to the third grade of junior high schools with MCS-like symptoms tend to go to bed later than the other students.

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Since the new government has launched in 2011, Republic of the Union of Myanmar is stepping toward to democracy and economic reforms. This paper briefly introduces environmental circumstances of Myanmar under great changes from the view point of environmental chemistry, aiming to figure out several potential problems in near future.

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