Gender and species differences in the metabolism of 1,3-butadiene to butadiene monoepoxide and butadiene diepoxide in rodents following low-level inhalation exposures.
Levels of butadiene monoepoxide (BDO) and butadiene diepoxide (BDO2) were compared in tissues of male Sprague-Dawley rats and male B6C3F1 mice and in tissues of male and female Sprague-Dawley rats following inhalation exposures to 62.5 ppm 1,3-butadiene (BD). In male rats, BDO2 levels were highest in blood and were present at a concentration of only 5 +/- 1 pmol/g. Following a 6-h exposure, the concentration of BDO2 in the blood, femurs, lung and fat of female rats was 3 to 7-fold that of male rats. Levels of BDO were similar in tissues of female and male rats. Generally, levels of BDO were approximately 3 to 8-fold greater in mouse tissues as compared with rat tissues following 4-h exposures to BD. In blood, 204 +/- 15 pmol/g BDO2 was detected in male mice, while in rats, blood BDO2 levels were 5 +/- 1 pmol/g. This study shows marked species differences in tissue levels of BD epoxides, particularly BDO2, in rats and mice, and is the first to show gender differences in BD metabolism.
Inhalation Toxicology Research Institute, Lovelace Biomedical and Environmental Research Institute, Albuquerque, NM 87185, USA.
J R
JR
Thornton-Manning
A R
AR
Dahl
W E
WE
Bechtold
R F
RF
Henderson
D000280:Administration, Inhalation; D000818:Animals; D002070:Butadienes / Q000008:administration & dosage / Q000378:metabolism*; D002273:Carcinogens / Q000378:metabolism*; D004852:Epoxy Compounds / Q000378:metabolism*; D005260:Female; D008297:Male; D051379:Mice; D051381:Rats; D017207:Rats, Sprague-Dawley; D012737:Sex Factors; D013045:Species Specificity
D002070:Butadienes; D002273:Carcinogens; D004852:Epoxy Compounds; C024370:3,4-epoxy-1-butene; C007366:diepoxybutane; C031763:1,3-butadiene