We conducted a nationwide case-control study in Finland to identify occupational risk factors for pancreatic cancer. We constructed the occupational exposure histories for 595 incident cases of primary exocrinic cancer of the pancreas and of 1,622 cancer controls, using three different methods. We found elevated odds ratios (OR) for ionizing radiation [OR = 4.3; 95% confidence interval (CI) = 1.6-11.4], nonchlorinated solvents (OR = 1.6-1.8), and pesticides (OR = 1.7; 95% CI = 0.8-3.4). Asbestos, chromates, cleaning agents, waxes, polishes, and most other exposures were not meaningfully associated with pancreatic cancer. Inorganic dust containing crystalline silica (OR = 2.0; 95% CI = 1.2-3.5), heat stress (OR = 2.2; 95% CI = 0.8-6.6), and rubber chemicals including acrylonitrile (OR = 2.1; 95% CI = 0.9-4.7) emerged as previously unsuspected risk factors. Occupational exposure probably has a small role in the etiology of pancreatic cancer in the present-day industrialized or postindustrial work environment.