Ethiodized Oil Emulsion 13 (EOE-13) is an intravenous liver-spleen specific CT contrast agent. We infused EOE-13 directly into the hepatic arteries of five rhesus monkeys. Normal saline was administered in the same fashion in two control animals. Serial laboratory studies showed no major toxicity over a seven-day period. Intra-arterial EOE-13 has potential usefulness in the evaluation of hepatic artery infusion chemotherapy.