A letter to the editor was presented which reported a study of 1353 deaths through 1988 among workers exposed to ethylene-oxide (75218). The study revealed standardized mortality ratios of 0.86 (14 deaths) for leukemia and 1.02 (43 deaths) for hematopoietic cancer. There was no dose response relation according to the duration of exposure. The present results demonstrated that workers with similar levels of exposure to ethylene-oxide were not at increased risk for these two cancers and that the statement in the earlier study, that the results were inconclusive, was overly conservative. With regard to nonHodgkin's lymphoma, using a broader category, the study indicated a significant standardized mortality ratio of 2.47 for men, but no upward trend according to the duration of exposure. Specific jobs, responsible for the excess lymphoma were not identified. Analyses of nonHodgkin's lymphoma based on death certificates were limited by the inconsistent classification of the disease and by revisions in the International Classification of Disease (ICD) over time. A reply was also presented by the authors of the study which was referred to in this letter. They contend that they stand by their original results and point out that the study presented above, although based on the same data as their own, had 1 more year of follow up and that their data included both ICD 200 and ICD 202 revisions, although the results for each was reported separately.