The pharmaco kinetics of diethanolamine in Sprague-Dawley rats following intravenous administration

In order to better understand the potential toxicity of diethanolamine (DEA ) and preparatory to physiologically-based pharmacokinetic model developmen t, the pharm. aco kinetics of DEA at high and low internal dose through 96- h post-dosing were determined in female Sprague-Dawley rats administered 10 or 100 mg/kg uniformly labeled C-14-DEA via intravenous injection. Clearan ce of DEA from blood was calculated to be approximately 84 ml/h/kg at the l ow dose, increasing to approximately 242 ml/h/kg at the high dose, The prim ary route of excretion of administered radioactivity, approximately 25-36%, was via the urine as parent compound. A majority of the administered radio activity was recovered in the tissues of treated rats, especially in the li ver and kidneys, suggesting a propensity of DEA or its metabolites for bio accumulation. An accumulation of radioactivity also occurred gradually in t he red blood cells from about 6-96 h post-dosing. Some evidence of dose dep endency in the fate of iv-administered DEA was observed, suggesting that sa turation of the bioaccumulation process(es) occurred at a dose level of 100 mg/kg. (C) 2001 Elsevier Science Ltd. All rights reserved.