title: Determinants of TCDD half-life in veterans of operation ranch hand.
abstract: The half-life of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) changed significantly with body fat and age in 337 members of Operation Ranch Hand, the Air Force unit responsible for the aerial spraying of Agent Orange in Vietnam. Using paired TCDD measurements derived from serum collected in 1982 and in 1987, we investigated how TCDD half-life varied with percent body fat (PBF), relative changes in PBF, and age. We found that half-life increased significantly with increasing PBF and decreased significantly with increasing relative change in PBF and with age. The median observed half-life of TCDD for these 337 veterans is 11.3 yr with a nonparametric 95% confidence interval of 10.0-14.1 yr.
authors.forename: W H
authors.initials: WH
authors.lastname: Wolfe
authors.forename: J E
authors.initials: JE
authors.lastname: Michalek
authors.forename: J C
authors.initials: JC
authors.lastname: Miner
authors.forename: J L
authors.initials: JL
authors.lastname: Pirkle
authors.forename: S P
authors.initials: SP
authors.lastname: Caudill
authors.forename: D G
authors.initials: DG
authors.lastname: Patterson
authors.forename: L L
authors.initials: LL
authors.lastname: Needham
mesh_terms: D000273:Adipose Tissue / Q000378:metabolism*; D000328:Adult; D000375:Aging / Q000378:metabolism; D006207:Half-Life; D006801:Humans; D008297:Male; D008875:Middle Aged; D008889:Military Personnel; D000072317:Polychlorinated Dibenzodioxins / Q000097:blood / Q000493:pharmacokinetics*; D014728:Veterans; D014744:Vietnam
chemical_list: D000072317:Polychlorinated Dibenzodioxins