title: Occupational exposures and the risk of amyotrophic lateral sclerosis.
abstract: To examine the associations of specific occupations and occupational exposures with the risk of amyotrophic lateral sclerosis (ALS) in the Swedish population.
  
  
  
  A nested case-control study was conducted in Sweden. Patients with ALS diagnosed during 1991-2010 (n=5020) were identified from the National Patient Register and 5 controls per case (n=25 100) were randomly selected from the general Swedish population, individually matched to cases by birth year and sex. Occupational history was obtained from the Swedish censuses in 1970, 1980 and 1990. The Nordic Occupational Cancer Study Job Exposure Matrix was used to identify exposures related to individual occupations. Conditional logistic regression was used to estimate ORs and their 95% CIs.
  
  
  
  Higher risk of ALS was associated with precision-tool manufacturing (OR 1.68, 95% CI 1.11 to 2.52) and glass, pottery and tile work (OR 1.76, 95% CI 1.03 to 3.00), whereas lower risk was associated with textile work (OR 0.44, 95% CI 0.21 to 0.91). None of the examined occupational exposures were associated with ALS risk overall. However, among individuals younger than 65 years of age, an association with a higher risk of ALS was found for formaldehyde (OR 1.29, 95% CI 1.00 to 1.65), and an association with a lower risk of ALS was found for methylene chloride (OR 0.49, 95% CI 0.26 to 0.93).
  
  
  
  We identified several occupations and occupational exposures that may be associated with the risk of ALS in Sweden. Occupational history obtained from censuses every 10 years remains a limitation of the study.
authors.affiliation: Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden.|Epidemiology Branch, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina, USA.
authors.forename: Tracy L
authors.initials: TL
authors.lastname: Peters
authors.affiliation: Epidemiology Branch, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina, USA.
authors.forename: Freya
authors.initials: F
authors.lastname: Kamel
authors.affiliation: Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Cecilia
authors.initials: C
authors.lastname: Lundholm
authors.affiliation: Unit of Epidemiology, Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Maria
authors.initials: M
authors.lastname: Feychting
authors.affiliation: Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Caroline E
authors.initials: CE
authors.lastname: Weibull
authors.affiliation: Epidemiology Branch, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina, USA.
authors.forename: Dale P
authors.initials: DP
authors.lastname: Sandler
authors.affiliation: Unit of Occupational Medicine, Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Pernilla
authors.initials: P
authors.lastname: Wiebert
authors.affiliation: Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Pär
authors.initials: P
authors.lastname: Sparén
authors.affiliation: Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Weimin
authors.initials: W
authors.lastname: Ye
authors.affiliation: Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Fang
authors.initials: F
authors.lastname: Fang
mesh_terms: D000690:Amyotrophic Lateral Sclerosis / Q000139:chemically induced* / Q000453:epidemiology; D016022:Case-Control Studies; D004574:Electromagnetic Fields / Q000009:adverse effects; D006801:Humans; D016273:Occupational Exposure / Q000009:adverse effects*; D010575:Pesticides / Q000009:adverse effects; D018570:Risk Assessment; D012307:Risk Factors; D013548:Sweden / Q000453:epidemiology
chemical_list: D010575:Pesticides
keywords: Amyotrophic Lateral Sclerosis; Job Exposure Matrix; Occupation