Reproductive-toxicologic assessment of the epoxides ethylene oxide, propylene oxide, butylene oxide, and styrene oxide.
Hardin-BD; Niemeier-RW; Sikov-MR; Hackett-PL
Scand J Work, Environ & Health 1983 Apr; 9(2):94-102
Teratogenic effects of inhaling ethylene-oxide (75218), propylene- oxide (75569), butylene-oxide (26249207) and styrene-oxide (96093) were investigated in rats and rabbits. Female Sprague-Dawley-rats were used for studies using ethylene-oxide and propylene-oxide. Wistar-rats and New-Zealand-white-rabbits were used for studies using butylene-oxide and styrene-oxide. Stainless steel dynamic inhalation chambers were used. Chamber concentrations were monitored at approximately 40 minute intervals by gas chromatography. Rabbits and rats were exposed to 270 milligrams per cubic meter (mg/m3) ethylene-oxide, 1189mg/m3 propylene-oxide or 737 and 2950mg/m3 butylene-oxide. Rats were exposed to 492mg/m3 and rabbits were exposed to 74 and 246mg/m3 styrene-oxide. Daily exposures were for 7 hours during different gestational periods. All fetuses were examined for external defects, for visceral defects after dissection, and for skeletal defects. For each of the epoxides the acute toxicity was similar in pregnant and non pregnant rats. Rats exposed to propylene-oxide 7 hours per day, 5 days per week, for 3 weeks before breeding had a significant reduction in the number of corpora lutea. Fewer mated rats were found pregnant following gestational exposure to styrene-oxide suggesting preimplantation loss. In rabbits exposed to styrene-oxide the number of resorptions per litter was increased in a concentration related manner. Fetal body weight and crown rump length were reduced in all ethylene-oxide exposed groups. External, visceral, and skeletal examinations revealed no treatment related effects. Fetal examinations revealed evidence of toxicity with all four epoxides. No overt teratogenic activity was observed for the epoxides although a number of morphological aberrations were detected. Species differences were noted. The authors conclude that prolonged exposure to oxides may reduce female reproductive potential.
NIOSH-Author; Teratogens; Epoxides; Animal-studies; Inhalants; Comparative-toxicology; Fetus; Fertility; Congenital-effects; Skeletal-defects;
Author Keywords: 1,2-epoxybutane; 1,2-epoxyethane; epoxyethylbenzene; 1,2-epoxypropane; ethyloxirane; inhalation teratogenesis; methyloxirane; oxirane
75-21-8; 75-56-9; 26249-20-7; 96-09-3
Scandinavian Journal of Work, Environment and Health