Relationships between concentrations of 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin serum and personal characteristics in U.S. Army Vietnam veterans

We examined the association between personal characteristics and concentrations of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in blood serum of 640 male U.S. Army Vietnam veterans. TCDD concentrations ranged from 1.1 to 16.2 pg/g wet weight (ppt) with a geometric mean of 3.8 ppt consistent with no past heavy exposure to TCDD. TCDD concentrations increased with body mass index on the order of 0.3 ppt per 10 kg of body weight for veterans of the same height. Concentrations were about 50% greater for black veterans aged 45 compared to black veterans aged 37. We found no association between age and TCDD concentration in non-blacks. Veterans living in the western U.S. had slightly lower concentrations than those living elsewhere. TCDD concentrations tended to be slightly greater in veterans who reported spraying or mixing herbicides while employed in farming or ranching and in those who reported employment at incinerators. Relationships between concentrations of TCDD and personal characteristics were similar for 94 Vietnam-era veterans who had served in the continental U.S. or Germany.