... (2010)— Review —AReview of Indoor Air Pollution and Health Problems from the Viewpoint of Environmental Hygiene: Focusing on the Studies of Indoor Air Environment in Japan Compared to Those of Foreign ... OCs)refers to total concentrations of multiple indoor air pollutants. It is used as a complementary indica-tor to decrease indoor pollution level in total and achieve healthy indoor air environment. 109) The ... 20–28 (in Japanese).113)Sakai, K., Kamijima, M., Sh ib ata, E., Ohn o, H. and Nakajima, T. (2009) Annual transition and seasonalvariation of indoor air pollution levels of 2-ethyl-1-hexanol in...