| Fungi are one of the indoor biocontaminants that can cause allergic symptoms and diseases. They can grow on almost any building material if there is enough moisture available. Therefore, water damage in buildings is often associated with mold problems. Epidemiological studies have shown that children living in mold/water-damaged houses exhibit more respiratory symptoms and diseases than children in non-problem houses. Indoor mold exposure has been assessed through parental questionnaire, visual inspection by trained personnel, short-term air sampling, or dust sampling. However, the relationship between the exposure level assessed by these methods and their association with health outcomes are not clearly understood. Moreover, fungal fragments are emerging as a potential allergenic airborne contaminant, but their health-related characteristics and methods for exposure assessment are poorly explored.On-site home visits, which included a questionnaire, visual observation and dust sampling, was conducted in 777 homes enrolled in the CCAAPS (Cincinnati Childhood Allergy and Air Pollution Study). The relationship between home characteristics and level of dustborne Alternaria allergen was investigated by using both concentration (mug/g) and loading (mug/m 2). Home characteristics that were most strongly associated with the Alternaria allergen levels were those affecting the transport and penetration of particles from outdoors to indoors: the presence of dogs, the season, and the type of the infants' primary activity room. This indicates that the major amount of indoor Alternaria originated from outdoor air. Another group of home characteristics was related with the indoor microclimate, which may affect mold growth and spore release: use of dehumidifier, cloth dryer venting into living quarters, high temperature, and low relative humidity. Visible mold was not associated with Alternaria allergen level. Allergen levels measured in concentration and loading units were associated with different home characteristics, and therefore, both of these units deserve to be included in the future studies. As multiple home characteristics, not including visible mold growth, affected allergen level, both visual observation and allergen sampling are needed for a more comprehensive exposure assessment.This study provides comprehensive information on current measurement strategies of indoor fungal exposure. None of the currently used methods is superior, and a combination of different methods is needed to obtain a more inclusive exposure profile for fungi and their allergens. A field-compatible method needs to be developed for the measurement and analysis of fungal fragments so that this overlooked exposure type can be included in future population-based studies. (Abstract shortened by UMI.)... |
