The worry about fallout in the US from the Nuclear Emergency in Japan is both exagerated and false. You will get more radiation from going to the Dentist than you will from the "Radioactive Cloud" floating to America. The initial radiation being released in the water vapor is extremely short-lived (7 minutes on average). Most of the rest is in Tritium Vapor form, which will precipitate out fairly quickly. (Ifyou have ever owned a watch that glowed in the dark, and didn't need to have a light source to make it glow, you had Tritium in it.) Most people are experiencing a Panic Reaction right now, and running out to buy Potassium Iodide Tablets to protect themselves. THIS WORKS ONLY WHILE YOU ARE IN AN AREA THAT IS CONTANIMATED, OR UNDER THE THREAT OF CONTANIMATION!!! The reason you use the iodine is so you don't get any radioactive iodine from the stuff you come in contact with. The tablets are easy for your body to process, and will help prevent the buildup of radioactive iodine in your system. If you are taking it now, with no threat, you are just wasting your money.