Study on the potential relationships between indoor culturable fungi, particle load and children respiratory health in Xi'an, China

Abstract

Fungi and particles exposure have been closely linked to children's upper respiratory illnesses. To determine the relationships between culturable fungi, particle exposure and children's respiratory illnesses, culturable fungi, particle concentration and size distribution were examined in homes in Xi'an, China. Culturable fungi species were identified and the organic & element carbon of PM2.5 were tested. The study was performed in 24 homes classified as “children, health” (reference) and “children, illness” (case) according to Xi'an questionnaires. The results showed noticeable differences in the particle and culturable fungi pollution characteristics between the case and reference homes. The average geometric mean diameter of total culturable fungi was smaller in case homes than in reference homes, but the inhalable fraction of that was larger in case homes than in references homes. The species of predominant culturable fungi were similar in the two categories of homes. It was determined that the culturable fungi species within a specific diameter range were linked with different kinds of children's respiratory illness. Particle mass concentration (in terms of inhalable, thoracic, alveolic and PM10 PM2.5, PM1), the ratio of organic carbon and elemental carbon in PM2.5 and particle distribution were also different between the reference homes and the case homes, which might indicate factors affecting children's respiratory health status. In addition, culturable fungi and particle concentrations showed good positive correlations. This study provides practical information in the etiology of children's respiratory symptoms in home indoor environments.