title: Ethylene oxide dose and dose-rate effects in the mouse dominant-lethal test.
abstract: In the dose-response study, male mice were exposed by inhalation to ethylene oxide (EtO) for 4 consecutive days. Mice were exposed for 6 hr per day to 300 ppm, 400 ppm, or 500 ppm EtO for a daily total of 1,800, 2,400, or 3,000 ppm X hr (total exposures of 7,200, 9,600 and 12,000 ppm X hr), respectively. In the dose-rate study, mice were given a total exposure of 1,800 ppm X hr per day, also for 4 consecutive days, delivered either at 300 ppm in 6 hr, 600 ppm in 3 hr, or 1,200 ppm in 1.5 hr. Quantitation of dominant-lethal responses was made on matings involving sperm exposed as late spermatids and early spermatozoa, the most sensitive stages to EtO. In the dose-response study, a dose-related increase in dominant-lethal mutations was observed, the dose-response curve proved to be nonlinear. In the dose-rate study, increasing the exposure concentrations resulted in increased dominant-lethal responses.
mesh_terms: D000393:Air Pollutants / Q000633:toxicity; D000818:Animals; D004305:Dose-Response Relationship, Drug; D005027:Ethylene Oxide / Q000633:toxicity*; D005260:Female; D005799:Genes, Dominant / Q000187:drug effects*; D005804:Genes, Lethal / Q000187:drug effects*; D008297:Male; D051379:Mice; D009152:Mutagenicity Tests; D009153:Mutagens; D011247:Pregnancy
chemical_list: D000393:Air Pollutants; D009153:Mutagens; D005027:Ethylene Oxide