Occupational exposure to ionizing and non-ionizing radiation and risk of glioma.
BACKGROUND
Although the aetiology of glioma is poorly understood, the higher incidence in males has long suggested an occupational cause.


OBJECTIVE
To investigate possible associations between occupational exposure to ionizing, ultraviolet (UV), radiofrequency (RF) and extremely low frequency (ELF) radiation and adult glioma risk.


METHODS
Case-control study using histologically confirmed cases of glioma first diagnosed between 1987 and 1991 in Melbourne, Australia, matched by age, sex and postcode of residence. A detailed occupational history was obtained for each subject. Exposure to radiation was assessed using a Finnish job exposure matrix (FINJEM) for all the radiation types as well as self-reports and expert hygienist review for RF and ionizing radiation. For ELF and UV, gender-specific FINJEM analysis was performed.


RESULTS
The study population consisted of 416 cases of glioma and 422 controls. The risk estimates given by FINJEM for ELF, RF and ionizing radiation were close to or below unity. Gender-specific analysis for UV showed odds ratios of 1.60 [95% confidence interval (CI) 0.95-2.69] and 0.54 (95% CI 0.27-1.07) for the highest exposed group of men and women, respectively (corresponding P value for trend was 0.03 and 0.04).


CONCLUSIONS
We did not find evidence of an association between glioma and occupational exposure to ELF, RF and ionizing radiation. UV radiation was associated with increased glioma risk for men but this result could have been confounded by other predominantly male occupational and lifestyle exposures associated with high UV. Further investigation of UV radiation and glioma risk is suggested.
Karipidis
Ken K
KK
Department of Epidemiology and Preventive Medicine, Monash University, Melbourne, Victoria 3800, Australia. ken.karipidis@arpansa.gov.au
Benke
Geza
G
Sim
Malcolm R
MR
Kauppinen
Timo
T
Giles
Graham
G
D000328:Adult; D001932:Brain Neoplasms / Q000209:etiology*; D004307:Dose-Response Relationship, Radiation; D004812:Epidemiologic Methods; D005260:Female; D005910:Glioma / Q000453:epidemiology / Q000209:etiology*; D006801:Humans; D008297:Male; D009381:Neoplasms, Radiation-Induced / Q000453:epidemiology / Q000209:etiology*; D009784:Occupational Diseases / Q000209:etiology*; D016273:Occupational Exposure / Q000009:adverse effects*; D011839:Radiation, Ionizing; D011840:Radiation, Nonionizing / Q000009:adverse effects; D014739:Victoria / Q000453:epidemiology