. >> reporter: every two years takeshi yamane comes for a checkup.e was just seven when the was dropped a mile and a half from his elementary school. everything simply went dark, he remembered. it was like being inside a cloud of black smoke. shielded from the blast by a building, yamane survived. ug was first brought for medical evaluation in 1948. today the retooled radiation tifects research foundation is funded by america and japan. >> what we learn here can be applied to everyone around the world. >> reporter: epidemiologist eric grant is studying 93,000 survivors. what is so unique about what you have stored here? >> we have the radiation dose. we have what they died of, when they got sick, our clinic has information about what diseases they suffered from. so together, this forms an incredibly rich set of data to study radiation effects. >> reporter: it's still a mystery why they are seeing survivors dying of heart disease in addition to cancers. the answer may lie in these freezers where more than 900,000 biosamples are stored from survivors o

. >> takeshi yamane has been diagnosed with two types of cancer. >> the scientists say humanity owes a debt of gratitude because you all are willing to be a part of these tests. >> it is strange to say it's an honor, he said, but if our data is of use, i'm gratified. the foundation has now been asked to study a much more recent nuclear disaster, fukushima. applying lessons from the last 70 years. seth doa ne, cbs news, hiroshima, japan. >> we'll be right back. only glucerna has carbsteady, clinically proven to help minimize blood sugar spikes. so you stay steady ahead. it's back to school time you think your car smells fine, but your passengers smell this... eliminate odors you've gone noseblind to for up to 30 days with the febreze car vent clip break out the febreze, and [inhale/exhale mnemonic] breathe happy. so you think this chip is nothing to worry about? well at safelite we know sooner or later, every chip will crack. these friends were on a trip when their windshield got chipped. so they scheduled at safelite.com... they didn't have to change their plans, or worry about a thi