Effects of gender and dormitory environment on sick building syndrome symptoms among college students in Tianjin, China

• Study association between gender and SBS symptoms.
• Discover the association between dorm environmental factors and SBS symptoms.
• Higher indoor air temperature and relative humidity was associated with a decrease of SBS symptoms.
• Lower air change rate was associated with a slightly increment of general and skin SBS symptoms.

A study of “dorm environment and college students' health” was carried out in Tianjin, China, 2006–2007. It consisted of two phases. In Phase I, 3712 students in 1569 dorm rooms reported sick building syndrome (SBS) symptoms. One out of three students reported general SBS symptoms, and one out of four reported mucosal or skin problems. Males and females represented the same age group; had the same kind of dwellings in the same geographical area; and led similar student lifestyles. Nonetheless, female students reported slightly more SBS symptoms than males. A “moldy odor” or “dry air” was perceived by occupants in 31% and 76% dorm rooms respectively. The adjusted odds ratio (AOR) of perceived moldy odor for general SBS symptoms was 2.4, for mucosal symptoms 2.2, and for skin symptoms 2.0. A sensation of “dry air”, was a significant risk factor for general and skin symptoms. In Phase II, 238 dorm rooms were inspected and measured. Local moldy odor around room corners or under radiators was reported by inspectors in 26% dorm rooms. The median air change rate, indoor air temperature and relative humidity in winter were 0.7 h−1, 21 °C and 40%, respectively. Local moldy odor perceived by inspectors was a significant risk factor for nose irritation (AOR 2.8). In winter, higher air change rate was associated with a slight decrement of general and skin SBS symptoms, while higher indoor air temperature and relative humidity were slightly associated with reduced SBS symptoms.