INDOOR AIR-QUALITY AND HEALTH - VALIDITY AND DETERMINANTS OF REPORTEDHOME DAMPNESS AND MOLDS

Background. Questionnaire-based surveys from several countries have co nsistently detected adverse health associated with home dampness and m ould growth. Methods. To test the validity of questions commonly used to indicate the presence of indoor mould, questionnaires were administ ered in 403 homes where dust samples were taken for viable fungi and a ir samples for ergosterol. Results. Geometric mean concentrations of t he total viable fungi were 255 (SE 116) x 10(3) CFU/g when mouldy odou rs were reported and 155 (SE 55) when odours were not reported (P = 0. 01). Similarly, reported water damage was associated with a 50% increa se (P = 0.06). Geometric mean concentrations of the predominantly indo or-source fungi, Aspergillus plus Penicillium, were twice as high when mould or mildew was reported than when not mentioned (P = 0.01). The presence of reported mould or water damage was unrelated to the presen ce of detectable levels of ergosterol. There was evidence for reportin g bias: in the presence of low concentrations of viable fungi in dust, respondents reporting allergies were more likely to report visible mo uld growth (odds ratio [OR] = 1.8, 95% confidence interval [CI]: 0.9-3 .5, P = 0.10. In the presence of elevated concentrations of dust fungi , respondents who smoked were less likely to report visible mould grow th, (OR = 0.4, 95% CI : 0.2-0.7, P = 0.005). Conclusions. Reported mou ld, water damage, and mouldy odours were associated with elevated leve ls of indoor fungi. However, inaccuracy was high and there was evidenc e of a systematic reporting bias. Future research should concentrate o n developing accurate objective measures of exposure to fungi, and the n use this information to develop valid questionnaires. Currently, obj ective measures, not questionnaires, are recommended to clarify the he alth effects of indoor fungi.