title: Production of silicon alloys is associated with respiratory symptoms among employees in Norwegian smelters.
abstract: OBJECTIVE
  To develop a qualitative exposure classification of employees in Norwegian smelters and to investigate the relationship between respiratory symptoms and occupational exposure using this classification.
  
  
  METHODS
  The 3,924 participants completed a standardised questionnaire including questions of respiratory symptoms, familial asthma, allergy, doctor-diagnosed asthma, smoking habits, previous exposure and occupation. The employees were classified according to their current job function: (1) line operators were employed full time on the production line, (2) non-exposed employees did not work in production, (3) the remaining employees were classified as non-line operators. The association between the prevalence of respiratory symptoms and job category was examined using multivariate logistic regression.
  
  
  RESULTS
  The mean age of the participants was 38.6 years (standard deviation 9.2 years), 88.5% were males. The odds ratios (OR) (95% confidence intervals in parenthesis) for dyspnoea, cough and phlegm regarding previous exposure compared with no previous exposure were 1.4 (1.1-1.7), 1.4 (1.2-1.8) and 1.3 (1.0-1.7), respectively. The OR in line operators compared with non-exposed employees was 1.2 (0.9-1.7) for dyspnoea, 1.3 (1.0-1.8) for cough and 1.9 (1.4-2.7) for phlegm. The OR for respiratory symptoms was higher in relation to previous exposure than current job function except for phlegm.
  
  
  CONCLUSIONS
  In Norwegian smelters respiratory symptoms appear to be positively related to both current job function and previous exposure. Previous exposure appears to be more important than current job function.
authors: Department of Medicine, Akershus University Hospital and Faculty of Medicine, University of Oslo, Postbox 75, 1478 Lørenskog, Norway. helle.laier@dadlnet.dk
authors: H Laier
authors: HL
authors: Johnsen
authors: V
authors: V
authors: Søyseth
authors: S M
authors: SM
authors: Hetland
authors: J Saltyte
authors: JS
authors: Benth
authors: J
authors: J
authors: Kongerud
mesh_terms: D000328:Adult; D000367:Age Factors; D005260:Female; D006801:Humans; D008297:Male; D008669:Metallurgy; D008875:Middle Aged; D009664:Norway / Q000453:epidemiology; D009784:Occupational Diseases / Q000209:etiology*; D016273:Occupational Exposure / Q000009:adverse effects*; D012140:Respiratory Tract Diseases / Q000209:etiology*; D012737:Sex Factors; D012828:Silicones / Q000633:toxicity*; D012907:Smoking; D013997:Time Factors
chemical_list: D012828:Silicones
references: Occup Environ Med. 2002 May;59(5):345-7
references: 11983851
references: Radiol Med. 1979 Oct;65(10):717-21
references: 554189
references: Occup Med. 2001 Apr-Jun;16(2):359-66
references: 11319057
references: Scand J Work Environ Health. 2002 Oct;28(5):328-32
references: 12432986
references: Scand J Work Environ Health. 1997 Oct;23(5):342-50
references: 9403464
references: Int Arch Occup Environ Health. 1980;46(1):1-9
references: 7380569
references: Eur Respir J. 2003 Sep;22(3):462-9
references: 14516136
references: Am J Ind Med. 2001 Aug;40(2):133-40
references: 11494340
references: Occup Med (Lond). 2000 Feb;50(2):103-6
references: 10829429
references: J Epidemiol Community Health. 2000 Dec;54(12):917-22
references: 11076988
references: Scand J Work Environ Health. 1989 Oct;15(5):364-70
references: 2799323
references: Br J Ind Med. 1989 Sep;46(9):629-35
references: 2789966
references: N Engl J Med. 1953 Jun 11;248(24):995-1001
references: 13046664
references: Eur Respir J. 1991 Mar;4(3):273-8
references: 1864342