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.
Thornton-Manning
J R
JR
Inhalation Toxicology Research Institute, Lovelace Biomedical and Environmental Research Institute, Albuquerque, NM 87185, USA.
Dahl
A R
AR
Bechtold
W E
WE
Henderson
R F
RF
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