title: High ambient Cladosporium spores were associated with reduced lung function in schoolchildren in a longitudinal study.
abstract: BACKGROUND
  In our previous longitudinal study, we found that exposure to current levels of ambient total fungal spores was related to a reduction of childhood lung function. However, the biological properties of various taxa of fungal spores varied greatly, as well as their health effects. In this study, we aimed to determine whether any specific fungal spores were responsible for observed changes in lung function.
  
  
  METHODS
  Measurement of lung function was conducted for 100 elementary and middle-school students on 5-10 occasions from October 2007 to November 2009 in New Taipei City, Taiwan. During the week of each lung function measurement, continuous daily concentrations of fungal spores were measured from Sunday to Saturday. The counts of fungal spores belonging to specific taxa were identified. A mixed-effect model with repeated measurements was used to analyze the association of lung function and exposure to each specific taxon of fungal spores. Forward stepwise regression was applied to determine which specific fungal spores were the most closely related to lung function changes. The non-linear relationship was examined using a generalized additive model. The piecewise linear regression was then applied to determine the threshold value.
  
  
  RESULTS
  A total of 824 measurements were obtained from 100 participants. Among all the species of fungal spores, only Cladosporium spores were found to be negatively associated with forced vital capacity (FVC) and forced expiratory volume in one second (FEV1) one day later. This association was stronger than the one between the total spore counts and lung function. The threshold of exposure where lung function effect became observable was approximately 1,500 spores/m(3).
  
  
  CONCLUSIONS
  This study showed that ambient Cladosporium was most strongly associated with the observed lung function changes among schoolchildren. Replication of these preliminary findings in other geographic areas with different populations would be warranted.
authors.affiliation: Department of Environmental and Occupational Medicine, National Taiwan University (NTU) College of Medicine and NTU Hospital, Taipei, Taiwan.
authors.forename: Bing-Yu
authors.initials: BY
authors.lastname: Chen
authors.affiliation: School of Public Health, Taipei Medical University, Taipei, Taiwan.
authors.forename: H
authors.initials: H
authors.lastname: Jasmine Chao
authors.affiliation: Institute of Occupational Medicine and Industrial Hygiene, NTU, Taipei, Taiwan.
authors.forename: Chang-Fu
authors.initials: CF
authors.lastname: Wu
authors.affiliation: Department of Epidemiology and Biostatistics, School of Public Health & Institute of Health and Environment, Seoul National University, Seoul, Republic of Korea.
authors.forename: Ho
authors.initials: H
authors.lastname: Kim
authors.affiliation: Environmental Epidemiology Group, School of Comprehensive Human Sciences, University of Tsukuba, Tsukuba, Japan.
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Honda
authors.affiliation: Department of Environmental and Occupational Medicine, National Taiwan University (NTU) College of Medicine and NTU Hospital, Taipei, Taiwan; Institute of Occupational Medicine and Industrial Hygiene, NTU, Taipei, Taiwan. Electronic address: leonguo@ntu.edu.tw.
authors.forename: Yue Leon
authors.initials: YL
authors.lastname: Guo
mesh_terms: D000391:Air Microbiology; D016902:Air Pollution, Indoor / Q000706:statistics & numerical data*; D002648:Child; D002963:Cladosporium / Q000254:growth & development*; D005260:Female; D005541:Forced Expiratory Volume; D006801:Humans; D019570:Inhalation Exposure / Q000706:statistics & numerical data*; D008137:Longitudinal Studies; D008297:Male; D012129:Respiratory Function Tests; D012140:Respiratory Tract Diseases / Q000453:epidemiology*; D013172:Spores, Fungal / Q000302:isolation & purification*; D014797:Vital Capacity
keywords: Children; Cladosporium; Forced expiratory volume in one second; Forced vital capacity; Fungal spores; Lung function