Abstract
Due to the Great East Japan earthquake and related disasters, many people are forced to evacuate from their own houses to temporally housing areas. About 72,000 of the temporally houses are being or has been built after the disaster in the prefectures of Miyagi, Fukushima, Iwate and so on. Meanwhile, there are some foreign reports on victims who unfortunately became chemical intolerance because of exposure to formaldehyde in indoor air of temporally houses after hurricane or earthquake attacks. To prevent such secondary disaster, Miyagi prefecture obligates builders to report indoor air concentrations of formaldehyde, toluene, xylene, ethylbenzene and styrene with a frequency of one house per one order, corresponding to one house per 50-60 houses. However, detailed and in-depth survey should be required for the prevention of indoor air pollution problem, because chemicals other than the five compounds potentially cause adverse health disorders. Then, authors have voluntary conducted a field survey on the indoor air concentrations of chemicals at 6 sites in 5 houses of one temporally housing area at Miyagi in 20 June 2011, under the cooperation of Miyagi prefectural government. Target substances were 3 carbonyl compounds, 43 Volatile Organic Compounds (VOCs) and TVOC (Total VOCs). The results showed the indoor air concentrations of chemicals whose indoor air guidelines were previously set were below the guideline levels at all sampling sites. However, TVOC concentrations ranged from 1700-3000μg/m3, 4-7.5 fold higher than the tentative guideline for TVOC. Unregulated chemicals by the governmental countermeasures contributed to such extraordinary high concentrations of TVOC in the tested temporally houses.
