May 1986, France : Map of I-131 deposits
Maps of iodine-131 and Cesoum-137 are similar following the same pattern. In early may 1986, iodine-131 surface activities were 5 to 10 times these of cesium-137, but they were halved every 8 days and divided by 1000 every 80 days. At the end of june, iodine had practically vanished. West of France ittle affected, the most contaminated departments lying east of a line Gard-Moselle. IRSN