The toxicology of potassium and sodium iodates: III. Acute and subacute oral toxicity of potassium iodate in dogs

Abstract

Summary The minimum lethal dose for potassium iodate administered orally to 8 fasted dogs, was estimated to be 200–250 mg/kg. Single doses of this compound at these levels invariably caused emesis. When emesis was prevented by morphine, anorexia, prostration, and death often ensued. Fatty changes in the viscera, necrotic lesions in the liver, kidney, and mucosa of the gastrointestinal tract and urinary bladder, and retinal degeneration were sometimes present after such high doses. All of these changes except retinal degeneration appeared to be reversible. In subacute toxicity studies with 4 dogs, repeated doses of KIO3 at levels of 6–100 mg/kg were given in milk or by capsule for a period of several months. Emesis followed by anorexia and listlessness sometimes occurred in these animals but during the last 3–7 weeks of the experimental period stabilization of weight and appetite took place at dosages varying from 60 to 90 mg/kg. The doses given during the final period averaged 4 per week. All dogs were in good condition at the end of the experiment. Pathologic changes in the sacrificed animals were confined largely to deposits of hemosiderin in the spleen, liver, and kidneys, and to mild to moderate inflammation of the mucosa of the gastrointestinal tract. Hematologic changes indicating a mild anemia were found in one dog given the most iodate.