title: Cross-shift study of exposure-response relationships between bioaerosol exposure and respiratory effects in the Norwegian grain and animal feed production industry.
abstract: OBJECTIVE
  We have studied cross-shift respiratory responses of several individual bioaerosol components of the dust in the grain and feed industry in Norway.
  
  
  METHODS
  Cross-shift changes in lung function and nasal congestion, as well as in respiratory and systemic symptoms of 56 exposed workers and 36 referents, were recorded on the same day as full-shift exposure to the inhalable aerosol fraction was assessed. Exposure-response associations were investigated by regression analysis.
  
  
  RESULTS
  The workers were exposed on average to 1.0 mg/m(3) of grain dust, 440 EU/m(3) of endotoxin, 6 µg/m(3) of β-1,3-glucans, 17×10(4)/m(3) of bacteria and 4×10(4)/m(3) of fungal spores during work. The exposure was associated with higher prevalence of self-reported eye and airway symptoms, which were related to the individual microbial components in a complex manner. Fatigue and nose symptoms were strongest associated with fungal spores, cough with or without phlegm was associated with grain dust and fungal spores equally strong and wheeze/tight chest/dyspnoea was strongest associated with grain dust. Bioaerosol exposure did not lead to cross-shift lung function decline, but several microbial components had influence on nose congestion.
  
  
  CONCLUSIONS
  Exposure to fungal spores and dust showed stronger associations with respiratory symptoms and fatigue than endotoxin exposure. The associations with dust suggest that there are other components in dust than the ones studied that induce these effects.
authors.affiliation: Department of Chemical and Biological Work Environment, National Institute of Occupational Health, Oslo, Norway.
authors.forename: Anne
authors.initials: A
authors.lastname: Straumfors
authors.affiliation: Department of Chemical and Biological Work Environment, National Institute of Occupational Health, Oslo, Norway.
authors.forename: Kari Kulvik
authors.initials: KK
authors.lastname: Heldal
authors.affiliation: Department of Chemical and Biological Work Environment, National Institute of Occupational Health, Oslo, Norway.
authors.forename: Wijnand
authors.initials: W
authors.lastname: Eduard
authors.affiliation: Faculty of Veterinary Medicine, Institute of Risk Assessment Sciences, Utrecht University, Utrecht, The Netherlands.
authors.forename: Inge M
authors.initials: IM
authors.lastname: Wouters
authors.affiliation: Department of Chemical and Biological Work Environment, National Institute of Occupational Health, Oslo, Norway.
authors.forename: Dag G
authors.initials: DG
authors.lastname: Ellingsen
authors.affiliation: Department of Occupational Medicine and Epidemiology, National Institute of Occupational Health, Oslo, Norway.
authors.forename: Marit
authors.initials: M
authors.lastname: Skogstad
mesh_terms: D000293:Adolescent; D000328:Adult; D000336:Aerosols; D000395:Air Pollutants, Occupational / Q000009:adverse effects* / Q000032:analysis; D000821:Animal Feed / Q000009:adverse effects*; D004391:Dust; D002523:Edible Grain / Q000009:adverse effects*; D004731:Endotoxins / Q000009:adverse effects / Q000032:analysis; D004784:Environmental Monitoring; D005260:Female; D006801:Humans; D007221:Industry; D019570:Inhalation Exposure / Q000009:adverse effects* / Q000032:analysis; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D009297:Nasal Mucosa / Q000382:microbiology; D009664:Norway / Q000453:epidemiology; D016273:Occupational Exposure / Q000009:adverse effects / Q000032:analysis; D012140:Respiratory Tract Diseases / Q000453:epidemiology* / Q000382:microbiology*; D012907:Smoking / Q000453:epidemiology; D013147:Spirometry; D011795:Surveys and Questionnaires; D055815:Young Adult
chemical_list: D000336:Aerosols; D000395:Air Pollutants, Occupational; D004391:Dust; D004731:Endotoxins
keywords: acoustic rhinometry; gas diffusion; microbial components; spirometry