Indoor fungus contamination in temporary houses in Sendai city

The Great East Japan Earthquake generated on March 11, 2011 brought damage to much of the northeast area of Japan. The required number of temporary houses is more than 50,000. Many disaster victims have to reside in temporary houses for the near- to long-term future. Fungus contamination is expected to be an ongoing problem, especially given increased residential humidity resulting from dew condensation which originates insufficiently insulation. This paper describes the results obtained by a survey of 40 temporary houses in Sendai city, Miyagi in August and October, 2011, March and September, 2012. We report that in 40 temporary houses, the highest fungal concentrations rose up to 46,420cfu/m³. Moreover, almost 100% of surveyed houses in summer exceeded AIJ standard 1,000cfu/m³. On the other hand, as the I/O ratio is over 1 greatly, and genera of airborne fungi and settled fungi are almost same, it became clear that settled fungi is major indoor pollution source. Thus, it is necessary to perform evaluation including settled fungus to elucidate the actual condition of fungus contamination in residential environment.