Gas-liquid chromatographic determination of total inorganic iodine in milk

Total inorganic iodine in milk is determined by conversion to iodobutanone, which is quantitated by gas-liquid chromatography and electron capture detection. As little as 10 microgram/L can be determined. The thyroid-active iodine content of milk can be determined rapidly with a relative standard deviation of 1.9%. Average recoveries for added iodide and iodine were 95.5 and 94.6%, respectively.