The cause-specific mortality experiences of 3105 members of the Oil, Chemical and Atomic Workers International Union was examined to determine if there were unusual patterns of fatal disease that might be indicative of hazardous agents in the work environment. Deaths among active union members that were reported by locals in Texas [USA] between 1947-1977 were identified through membership records; proportionate mortality was analyzed in several broad industrial categories. PMR [proportionate mortality rate] for cancers of the liver and biliary passages, pancreas, lung and skin were elevated among refinery and petrochemical plant workers; risks did not increase with length of membership. Increased relative frequencies of stomach cancer, cancer of the brain, leukemia and multiple myeloma were confined to white males in the same category who had been union members for 10 or more yr. Excess deaths from stomach cancer and brain cancer were found among white male members employed at one specific oil refinery and petrochemical plant. Observed numbers of deaths from cancer of the stomach were greater than expected among whites and nonwhites, and an elevated PMR for lung cancer among nonwhites was found at an additional plant. Workers in this industry may be at increased risk of certain cancers.