title: Occupational exposure and amyotrophic lateral sclerosis in a prospective cohort.
abstract: To prospectively study suspected occupational risk factors for amyotrophic lateral sclerosis (ALS).
  
  
  
  For this case-cohort analysis within the prospective Netherlands Cohort Study, 58 279 men and 62 573 women aged 55-69 years at enrolment in 1986 were followed up for 17.3 years on ALS mortality. Information on occupational history and potential confounders were collected at baseline through a self-administered questionnaire and entered for a random subcohort (2092 men and 2074 women) and ALS deaths (76 men and 60 women). Occupational exposure to solvents, pesticides, metals, extremely low frequency magnetic fields (ELF-MFs) and electrical shocks was estimated by means of job exposure matrices (JEMs). Associations between ever/never occupationally exposed and cumulative exposure and ALS mortality were analysed by gender using Cox regression.
  
  
  
  Occupational exposure to ELF-MF showed a possible association with ALS mortality among men: HR for ever holding a job with high exposure versus background 2.19 (95% (CI): 1.02 to 4.73) and HR for the highest tertile of cumulative exposure versus background 1.93 (95% CI 1.05 to 3.55).
  
  
  
  These results strengthen the evidence suggesting a positive association between ELF-MF exposure and ALS. We did not replicate earlier positive findings for other occupational exposures.
authors.affiliation: Division of Environmental Epidemiology, Institute for Risk Assessment Sciences, Utrecht University, Utrecht, The Netherlands.
authors.forename: Tom
authors.initials: T
authors.lastname: Koeman
authors.affiliation: Division of Environmental Epidemiology, Institute for Risk Assessment Sciences, Utrecht University, Utrecht, The Netherlands.
authors.forename: Pauline
authors.initials: P
authors.lastname: Slottje
authors.affiliation: Department of Epidemiology, GROW School for Oncology and Developmental Biology, Maastricht University Medical Centre, Maastricht, Netherlands.
authors.forename: Leo J
authors.initials: LJ
authors.lastname: Schouten
authors.affiliation: Division of Environmental Epidemiology, Institute for Risk Assessment Sciences, Utrecht University, Utrecht, The Netherlands.|Department of Neurology and Neurosurgery, Brain Center Rudolf Magnus, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: Susan
authors.initials: S
authors.lastname: Peters
authors.affiliation: Division of Environmental Epidemiology, Institute for Risk Assessment Sciences, Utrecht University, Utrecht, The Netherlands.
authors.forename: Anke
authors.initials: A
authors.lastname: Huss
authors.affiliation: Department of Neurology and Neurosurgery, Brain Center Rudolf Magnus, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: Jan H
authors.initials: JH
authors.lastname: Veldink
authors.affiliation: Division of Environmental Epidemiology, Institute for Risk Assessment Sciences, Utrecht University, Utrecht, The Netherlands.
authors.forename: Hans
authors.initials: H
authors.lastname: Kromhout
authors.affiliation: Department of Epidemiology, GROW School for Oncology and Developmental Biology, Maastricht University Medical Centre, Maastricht, Netherlands.
authors.forename: Piet A
authors.initials: PA
authors.lastname: van den Brandt
authors.affiliation: Division of Environmental Epidemiology, Institute for Risk Assessment Sciences, Utrecht University, Utrecht, The Netherlands.|Julius Centre for Public Health Sciences and Primary Care, University Medical Center, Utrecht, The Netherlands.
authors.forename: Roel
authors.initials: R
authors.lastname: Vermeulen
mesh_terms: D000368:Aged; D000690:Amyotrophic Lateral Sclerosis / Q000453:epidemiology / Q000209:etiology*; D004574:Electromagnetic Fields / Q000009:adverse effects*; D005260:Female; D006801:Humans; D008297:Male; D008670:Metals / Q000009:adverse effects; D008875:Middle Aged; D009426:Netherlands / Q000453:epidemiology; D009784:Occupational Diseases / Q000453:epidemiology / Q000209:etiology*; D016273:Occupational Exposure / Q000009:adverse effects*; D010575:Pesticides / Q000009:adverse effects; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012307:Risk Factors; D017678:Sex Distribution; D012997:Solvents / Q000009:adverse effects; D011795:Surveys and Questionnaires
chemical_list: D008670:Metals; D010575:Pesticides; D012997:Solvents
keywords: Amyotrophic Lateral Sclerosis; Electromagnetic fields; metals; occupation; pesticides