Occupational exposure to crystalline silica and risk of lung cancer: a multicenter case-control study in Europe.
BACKGROUND
The role of crystalline silica dust as a possible cause of lung cancer has been controversial. Relatively few large community-based studies have been conducted to investigate the lung cancer risk from exposure to silica at low levels, taking into account potential confounding factors.


METHODS
Detailed lifestyle and occupational information were collected from 2852 newly diagnosed cases of lung cancer and 3104 controls between 1998 and 2002 in 7 European countries. For each job held, local experts assessed the probability, intensity, and duration of silica exposure.


RESULTS
Occupational exposure to crystalline silica was associated with an increased risk of lung cancer (odds ratio = 1.37; 95% confidence interval = 1.14-1.65). This risk was most apparent for the upper tertile of cumulative exposure (OR = 2.08; 95% CI = 1.49-2.90; P for trend <0.0001), duration of exposure (1.73; 1.26-2.39; P for trend = 0.0001) and weighted duration of exposure (1.88; 1.35-2.61; P for trend <0.0001). We did not observe any interaction beyond a multiplicative model between tobacco smoking and silica exposure.


CONCLUSIONS
Our results support the hypothesis that silica is an important risk factor for lung cancer. This risk could not be explained by exposure to other occupational carcinogens or smoking, and it was present for the main histologic types of lung cancer, different sources of silica exposure, and different industrial settings.
Cassidy
Adrian
A
Roy Castle Lung Cancer Research Programme, University of Liverpool Cancer Research Centre, University of Liverpool, United Kingdom. cassidya@liv.ac.uk
't Mannetje
Andrea
A
van Tongeren
Martie
M
Field
John K
JK
Zaridze
David
D
Szeszenia-Dabrowska
Neonila
N
Rudnai
Peter
P
Lissowska
Jolanta
J
Fabianova
Eleonora
E
Mates
Dana
D
Bencko
Vladimir
V
Foretova
Lenka
L
Janout
Vladimir
V
Fevotte
Joelle
J
Fletcher
Tony
T
Brennan
Paul
P
Boffetta
Paolo
P
D000230:Adenocarcinoma / Q000453:epidemiology* / Q000209:etiology; D000328:Adult; D000368:Aged; D000395:Air Pollutants, Occupational / Q000009:adverse effects*; D018288:Carcinoma, Small Cell / Q000453:epidemiology* / Q000209:etiology; D002294:Carcinoma, Squamous Cell / Q000453:epidemiology* / Q000209:etiology; D016022:Case-Control Studies; D005060:Europe / Q000453:epidemiology; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000453:epidemiology* / Q000209:etiology; D008297:Male; D008875:Middle Aged; D016273:Occupational Exposure / Q000009:adverse effects*; D009790:Occupations / Q000706:statistics & numerical data; D016017:Odds Ratio; D018570:Risk Assessment; D012822:Silicon Dioxide / Q000009:adverse effects*; D012907:Smoking / Q000453:epidemiology
D000395:Air Pollutants, Occupational; D012822:Silicon Dioxide