Associations of building characteristics and lifestyle behaviors with home dampness-related exposures in Shanghai dwellings

• Home damp-related indicators are quantitatively described in Shanghai residences.
• Children's mother report notably more indicators than father and other respondent.
• Associations among children with or without asthma had no notable difference.
• Condensation on windows did not effectively indicate home dampness in Shanghai.
• Living on the ground or top floor and fish-keeping are risk factors for home damp.

A total of 15,266 questionnaires from 1 to 8 year-old children was used to investigate the prevalences of home dampness-related indicators and their associations with the respondent's residential characteristics and lifestyle behaviors in Shanghai, China. Most of the questionnaires were filled out by one of the child's parents (69.0% by mother and 24.9% by father). The prevalence of visible mold (VMS) was 7.9%, visible damp stains (VDS) 15.2%, windows pane condensation (WPC) 54.9%, water damage (WD) 11.9%, damp clothing and/or bedding (DCB) 42.0%, and moldy odor (MO) 11.9%, respectively. Questionnaires submitted by the child's mother noted significantly more dampness-related indicators than those submitted by the father and other respondents. Residences on the ground floor or top floor were strongly and positively associated with VMS and VDS in comparison with residences on the other floors of the dwelling building. Keeping fish in the current residence also had significant and positive associations with VDS, WPC, and WD. Having exhaust fan in the bathroom and/or opening the windows of the child’ bedroom, and frequently cleaning rooms was strongly associated with reduced dampness-related indicators in the child’ bedroom. Most of these associations among families without asthmatic children were similar to among the whole samples. Therefore, we concluded that studies regarding to home dampness-related evaluation by questionnaire should carefully considered report bias. Living on the ground floor or top floor and fish-keeping are risk factors for home dampness-related exposures. Improving home ventilation and increasing frequency of home cleaning could effectively reduce these exposures.