Relationship between sick building syndrome and indoor environmental factors in newly built Japanese dwellings

Abstract

Indoor air contaminants and dampness in dwellings have become important environmental health issues. The aim of this study is to clarify which factors are related to sick building syndrome (SBS) in newly built dwellings at Hokkaido, Japan, through a comprehensive evaluation of the indoor environment and validated sick building symptom questionnaires. The symptoms of 343 residents in 104 detached houses were surveyed by standardized questionnaires, and the concentrations of formaldehyde, acetaldehyde, volatile organic compounds (VOCs), airborne fungi, and dust mite allergen in their living rooms were measured. By summing the presence or absence of the five dampness indicators (condensations, mold growth, moldy odor, high air humidity of the bathroom, water leakage), a dampness index was calculated. SBS symptoms were found in 21.6% of surveyed individuals. In a fully adjusted multivariate logistic regression analysis, the dampness index [odds ratio (OR) = 1.50; 95% confidence interval (CI): 1.06-1.11], log formaldehyde (OR = 23.79, 95% CI: 2.49-277.65), and log alpha-pinene (OR = 2.87, 95% CI: 1.36-6.03) had significantly higher ORs for SBS symptoms. However, other VOCs, airborne fungi, and dust mite allergen did not have significantly higher ORs. Dampness, formaldehyde, and alpha-pinene were significantly related to SBS symptoms in newly built dwellings. We should, therefore, take measures to reduce the chemicals and dampness in dwellings.