Quantitative Whole Body Autoradiographic Disposition of Glycol Ether in Mice: Effect of Route of Administration

Glycol ethers such as ethylene glycol monomethyl ether (EGME)are common solvents used in many industrial products. A largenumber of individuals are exposed to EGME through differentexposure routes. We investigated the differential distributionof EGME following various routes of administration using wholebody autoradiographic (WBA) techniques. Male B6C3F1 mice weretreated with tracer iv or oral doses of 2-¹⁴C]EGME.(4.05 µgEGME/kg equivalent to 0.8 mCi/kg) and euthanized at 1 and 24hr following treatment. In both groups of animals the highestlevels of radioactivity were detected in the liver, urinarybladder, bone marrow, kidney, and epididymis, at 1- and 24-hrtime periods. Computer-assisted quantitation of WBA indicatedthat there was markedly higher deposition of 2-¹⁴ and/or itsmetabolites in various tissues of the orally treated animalsthan in animals treated intravenously. Our studies also suggestthat 2-¹⁴C]EGME is rapidly distributed either from blood orstomach to various tissues. Preferential deposition of radioactivityin the peripheral tissues of the bone, with a progressive inwardaccumulation in the bone marrow, was observed. Selective permeabilityof EGME and/or its metabolites was indicated by the higher uptakeby the epididymis than that by testis. The high levels of radioactivityin biosynthetically active tissues, e.g., the liver, bone marrow,and gastric mucosa, is an indication of persistent interactionof the compound with cellular components of these tissues. Theseinteractions may lead to EGME toxicity.