Case-Control study for the Association Between Indoor Environmental Factors and Children’s Health Problems in Japan-Part1 a nationwide questionnaire study among 1664 primary school students.

Recent studies show the number of people affected by biological contaminants have increased every year in Japan. An epidemiological investigation on 4th and 5th grade primary school students was conducted in order to clarify the relationship between indoor environment and children’s health problems. A case-control study adopted ATS-DLD-American Thoracic Society-Division of Lung Diseases- questionnaire for evaluation of respiratory symptoms and allergies was conducted for 2574 primary school students (1664 responded) across Japan. The visible presence of mold both living room and children’s bedroom excluding window (such as wall, floor or closet) was observed to be significantly associated with bronchial hypersensitivity (OR=3.05 95% Cl: 1.38-6.73). Also, the occurrence of respiratory symptoms and allergic symptoms were significantly associated in homes using humidifier. These results showed that home environmental factors had serious risk factors for allergic symptoms. In particular, indoor mold and water stain were strongly influence on respiratory symptoms among children in Japan.