title: Pharmacokinetics and metabolism of benzene in Zymbal gland and other key target tissues after oral administration in rats.
abstract: Solid tumors have been reported in the Zymbal gland, oral and nasal cavities, and mammary gland of Sprague-Dawley rats following chronic oral administration of benzene. The cause for the specificity of such lesions remains unclear, but it is possible that tissue-specific metabolism or pharmacokinetics of benzene is responsible. Metabolism and pharmacokinetic studies were carried out in our laboratory with 14C-benzene at oral doses of 0.15 to 500 mg/kg to ascertain tissue retention, metabolite profile, and elimination kinetics in target and nontarget organs and in blood. Findings from those studies indicate the following: a) the Zymbal gland is not a sink or a site of accumulation for benzene or its metabolites even after a single high dose (500 mg/kg) or after repeated oral administration; b) the metabolite profile is quantitatively different in target tissues (e.g., Zymbal gland, nasal cavity), nontarget tissues and blood; and (c) pharmacokinetic studies show that the elimination of radioactivity from the Zymbal gland is biphasic.
authors: Mobil Oil Corporation, Environmental and Health Science Laboratory, Princeton, NJ 08540.
authors: L K
authors: LK
authors: Low
authors: J R
authors: JR
authors: Meeks
authors: K J
authors: KJ
authors: Norris
authors: M A
authors: MA
authors: Mehlman
authors: C R
authors: CR
authors: Mackerer
mesh_terms: D000284:Administration, Oral; D000818:Animals; D001554:Benzene / Q000008:administration & dosage / Q000378:metabolism* / Q000493:pharmacokinetics; D002250:Carbon Radioisotopes; D002851:Chromatography, High Pressure Liquid; D004424:Ear Canal / Q000378:metabolism; D005260:Female; D006207:Half-Life; D007408:Intestinal Absorption; D009297:Nasal Mucosa / Q000378:metabolism; D009928:Organ Specificity; D051381:Rats; D011919:Rats, Inbred Strains; D012627:Sebaceous Glands / Q000378:metabolism; D014018:Tissue Distribution
chemical_list: D002250:Carbon Radioisotopes; D001554:Benzene