cakes were weighed after cooking, and one was used as a standard. The others were fed to volunteer subjects, who then collected all feces and urine separately for five days. I’s’ uptake by the thyroid gland was prevented by the administration of
carbimazole in a dose of 15 mg. given every 6 hours during the I)eriod of collection. Radioactivity in feces, urine and in the homogenized standard fish cake was counted in a well-type scintillation counter.