the radioactive iodine from the environment. you also get it in table salt, but if you take a gigantic amount of it, it fills up your thyroid and is a protective measure against thyroid cancer, and that's the reason for that. people who live near nuclear power plants in the united states are advised to keep a supply of potassium iodine in their medicine cabinets in case there's an accident. >> okay. nbc's bob bazell there in tokyo. i'm sure we'll check in with you again. thanks for joining us live. meantime, we are getting some incredible new pictures in of the tsunami's impact, and you're about to see this amateur video. it shows the immense power there. entire towns were completely inundated as the surging waters swept away the cars, buses, homes in their path. look at that bus, trying to out-run the water. see that one going on the side? they're like, get me out of here. joining me live on the phone from tokyo is umiko ono with "the wall street journal japan" online edition. with a good day to you. as we are looking at these incredible pictures there, are you seeing similar images of the