[en] In this third year of our study on the transport and distribution of ¹²⁹I in the local environment, our efforts have been concentrated on development of rapid and reliable sampling methods for the routine recovery of iodine from precipitation, surface waters, vegetation and aerosols, periodic recovery and analysis of iodine in milk, thyroids, surface waters and precipitation, and resolution of discrepancies between our interlaboratory standard monitors and the standard ¹²⁹I solution prepared and distributed by the National Bureau of Standards (NBS SRM 4949). Our program has succeeded in all these endeavors, except in the development of a reliable sampling method for local aerosols. Publication of the results of our analyses has been delayed by the monitor discrepancies, but no analytical results were lost