Production of silicon alloys is associated with respiratory symptoms among employees in Norwegian smelters.
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.
Johnsen
H Laier
HL
Department of Medicine, Akershus University Hospital and Faculty of Medicine, University of Oslo, Postbox 75, 1478 Lørenskog, Norway. helle.laier@dadlnet.dk
Søyseth
V
V
Hetland
S M
SM
Benth
J Saltyte
JS
Kongerud
J
J
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
D012828:Silicones
Occup Environ Med. 2002 May;59(5):345-7
11983851
Radiol Med. 1979 Oct;65(10):717-21
554189
Occup Med. 2001 Apr-Jun;16(2):359-66
11319057
Scand J Work Environ Health. 2002 Oct;28(5):328-32
12432986
Scand J Work Environ Health. 1997 Oct;23(5):342-50
9403464
Int Arch Occup Environ Health. 1980;46(1):1-9
7380569
Eur Respir J. 2003 Sep;22(3):462-9
14516136
Am J Ind Med. 2001 Aug;40(2):133-40
11494340
Occup Med (Lond). 2000 Feb;50(2):103-6
10829429
J Epidemiol Community Health. 2000 Dec;54(12):917-22
11076988
Scand J Work Environ Health. 1989 Oct;15(5):364-70
2799323
Br J Ind Med. 1989 Sep;46(9):629-35
2789966
N Engl J Med. 1953 Jun 11;248(24):995-1001
13046664
Eur Respir J. 1991 Mar;4(3):273-8
1864342