Epidemiological studies on ethylene oxide and cancer: an updating.

In 1959, Dr Lars Ehrenberg and a coworker warned the Swedish authorities that ethylene oxide, a common chemical, constituted a potential cancer hazard. Twenty years later, the first epidemiological study and case reports were published indicating an increased cancer risk after occupational exposure to ethylene oxide. An updating of three small Swedish cohorts comprising 709 employees revealed 33 deaths from cancer whereas 20 were expected from national average rates. The excess was due mainly to an increased risk of stomach cancer in one production plant and an excess of blood and lymphatic malignancies in all three cohorts. The results are in accordance with the results of clastogenic, animal and short-term tests and support Professor Ehrenberg's hypothesis, formulated 28 years ago.