title: Temporal Trend in Wood Dust Exposure During the Production of Wood Pellets.
abstract: Wood dust data collected in the production of wood pellets during 2001 to 2013 were evaluated to study a temporal trend in inhalation exposure.
  
  
  
  A linear mixed effects model of natural ln-transformed data was used to express the relative annual difference in inhalation wood dust exposure.
  
  
  
  There was an annual decrease of -20.5% of the geometric mean wood dust exposure during 2001 until 2013. The results were based on 617 inhalable dust samples collected at 14 different production units. The exposure to wood dust at the industrial premises investigated has decreased from a relatively high level of 6.4 mg m-3 in 2001 to 1.0 mg-3 in 2013. The Swedish Occupational Exposure Limit (SOEL) of 2 mg m-3 may still be exceeded.
  
  
  
  Analysis of the temporal trend in soft wood production units revealed declines in exposure of 20.5% per annum. It is important that precautions are taken to protect workers from a hazardous exposure to wood dust at the premises as the SOEL of 2 mg m-3 at some occasions is still exceeded. Additional measurements of wood dust exposure should be carried out on a regular basis in wood pellet production units in Sweden as well in other countries.
authors.affiliation: Department of Occupational and Environmental Medicine, Umeå University, Umeå SE90187, Sweden.
authors.forename: Kåre
authors.initials: K
authors.lastname: Eriksson
authors.affiliation: Department of Occupational and Environmental Medicine, Örebro University Hospital, Örebro SE70185, Sweden.
authors.forename: Ing-Liss
authors.initials: IL
authors.lastname: Bryngelsson
authors.affiliation: Department of Occupational and Environmental Medicine, Örebro University Hospital, Örebro SE70185, Sweden.
authors.forename: Katja
authors.initials: K
authors.lastname: Hagström
mesh_terms: D000395:Air Pollutants, Occupational / Q000032:analysis*; D004391:Dust / Q000032:analysis*; D004784:Environmental Monitoring / Q000379:methods; D006801:Humans; D007221:Industry; D019570:Inhalation Exposure / Q000032:analysis* / Q000706:statistics & numerical data*; D016273:Occupational Exposure / Q000706:statistics & numerical data*; D013548:Sweden; D014934:Wood / Q000032:analysis*
chemical_list: D000395:Air Pollutants, Occupational; D004391:Dust
keywords: analysis; dust; mixed; model; wood