Asbestos, cement, and cancer in the right part of the colon.
OBJECTIVE
The aim was to investigate associations between exposure to mineral fibres and dust, and cancer in subsites within the large bowel.


METHODS
Pooled retrospective cohort studies.


METHODS
Blue collar workers, employed for at least one year in different trades; asbestos cement or cement workers (n = 2507), other industrial workers (n = 3965), and fishermen (n = 8092).


METHODS
Standardised incidence ratios (SIRs, national reference rates) were calculated for cause specific cancer morbidity between 1958 and 1989. The observation period began 15 years after first employment.


RESULTS
The asbestos cement and cement workers had a slightly increased risk of colorectal cancer (SIR 1.5; 95% confidence interval (95% CI) 1.1-2.0). This was due to an increase only in the right part of the colon (SIR 2.5; 95% CI 1.6-3.8). The ratio of right (7th revision of the International Classification of Diseases ICD-7) 1530-1531)/left (ICD-7 1532-1533) colon cancer among the asbestos cement and cement workers of 4.8 differed significantly from the ratio both among the other blue collar workers (0.4) and among the fishermen (1.5). As the sensitivity and accuracy was insufficient, mortality data did not show the excess of cancers in the right part of the colon.


CONCLUSIONS
An increased incidence of cancer in the right part of the colon was evident in the asbestos cement and cement workers. The distribution of cancers within the colon was noticeably different from that in other blue collar workers, indicating that our findings cannot be explained by socioeconomic confounding factors. A detailed and appropriate disease classification, based on incidence data, is necessary in order not to obscure or underestimate effects of exposure in epidemiological studies on colorectal cancer.
Jakobsson
K
K
Department of Occupational and Environmental Medicine, University Hospital, Lund, Sweden.
Albin
M
M
Hagmar
L
L
D001194:Asbestos / Q000009:adverse effects*; D015331:Cohort Studies; D003106:Colon / Q000473:pathology; D003110:Colonic Neoplasms / Q000453:epidemiology / Q000209:etiology* / Q000473:pathology; D004391:Dust / Q000009:adverse effects*; D006801:Humans; D008297:Male; D008903:Minerals / Q000009:adverse effects; D009017:Morbidity; D009369:Neoplasms / Q000453:epidemiology / Q000209:etiology; D012004:Rectal Neoplasms / Q000453:epidemiology / Q000209:etiology; D012189:Retrospective Studies; D013548:Sweden / Q000453:epidemiology
D004391:Dust; D008903:Minerals; D001194:Asbestos