If you want to verify and see for yourself, go to the link and search for potassium iodide (search results aren't linkable).
FYI.
fwiw : I heard an analysis for the time following the initial Fukushima ‘plume’ that drifted to the USA, of cancers - and particular pockets where it occurred.
These corresponded with where there was RAINFALL at that time. And were scattered around the US, I think one was around Philadelphia.