Workplace exposures and oesophageal cancer

Objectives-To describe the relation between oesophageal cancer and many occ upational circumstances with data from a population based case-control stud y. Methods-Cases were 99 histologically confirmed incident cases of cancer of the oesophagus, 63 of which were squamous cell carcinomas. Various control groups were available; for the present analysis a group was used that compr ised 533 population controls and 533 patients with other types of cancer. D etailed job histories were elicited from all subjects and were translated b y a team of chemists and hygienists for evidence of exposure to 294 occupat ional agents. Eased on preliminary results and a review of literature, a se t of 35 occupational agents and 19 occupations and industry titles were sel ected for this analysis. Logistic regression analyses were adjusted for age , birthplace, education, respondent (self or proxy), smoking, alcohol, and beta-carotene intake. Results-Sulphuric acid and carbon black showed the strongest evidence of an association with oesophageal cancer, particularly squamous cell carcinoma. Other substances showed excess risks, but the evidence was more equivocal- namely chrysotile asbestos, alumina, mineral spirits, toluene, synthetic ad hesives, other paints and varnishes, iron compounds, and mild steel dust. T here was considerable overlap in occupational exposure patterns and results for some of these substances may be mutually confounded. None of the occup ations or industry titles showed a clear excess risk; the strongest hints w ere for warehouse workers, food services workers, and workers from the misc ellaneous food industry. Conclusions-The data provide some support for an association between oesoph ageal cancer and a handful of occupational exposures, particularly sulphuri c acid and carbon black. Many of the associations found have never been exa mined before and warrant further investigation.