MILES O’BRIEN: When I met him in 2012, radiation biophysicist Evan Douple was the associate chief of research at the Radiation Effects Research Foundation. The joint Japanese and U.S. study has been following the survivors of the atomic bombings of Hiroshima and Nagasaki for nearly 70 years.
MILES O’BRIEN: Ninety-four thousand irradiated bomb survivors volunteered to become subjects. Another 26,000 who lived in other Japanese cities during the bombings, but were not exposed to radiation, were included as a comparison or control group.
Today, about a third of the exposed and comparison subjects are still alive, many making routine pilgrimages up a hill overlooking the once devastated city of Hiroshima to undergo medical exams. Their blood is routinely analyzed, researchers on the lookout for damaged chromosomes and other signs of disease.
Over the years, they have frozen thousands of blood and tissue samples.
Among the findings over the years: Thyroid cancer and leukemia are the first to strike. Solid cancers come 10 to 30 years later. Young people are more susceptible to developing cancer than adults, and women are more susceptible than men. Perhaps the most important, a single exposure increases cancer risk for life.
The bottom line? Of 94,000 survivors studied over 70 years, about 1,000 additional cases of cancer can be attributed to radiation from the bombs.
MILES O’BRIEN: Radiation epidemiologist John Boice is hoping to address that limitation. He is spearheading a study of workers from the Manhattan Project, atomic veterans who witnessed atmospheric bomb tests, utility employees at nuclear power plants, and medical professionals, one million in all.
Radiation exposure data captured by the dosimeters routinely worn by these workers over the years is compared with their health history and cause of death.
JOHN BOICE: So, when we complete this study, that we will be able to say what the risks are from these various levels of radiation. Are they the same as Hiroshima and Nagasaki? Are they lower? Are they higher?
MILES O’BRIEN: Some studies suggest our bodies can fight back and repair damage caused by low-level, yet chronic, exposure to radiation. But no one is sure.
[…]DAVID BRENNER: What we want to do is to be able to expose a cell to radiation, but not expose all the neighbor cells to radiation, because that’s actually what — the real-life situation at very, very low doses.
MILES O’BRIEN: This isn’t just an academic pursuit. The atomic bomb survivors study is the basis of risk estimates for everything from doses in medical care, to work rules for radiation workers, to evacuation orders in the wake of a nuclear power plant meltdown.
But these rules, which can affect so many lives in so many devastating ways, are based solely on educated guesswork. In January 2015, the U.S. House passed the low-dose radiation bill which would provide funds to begin a large study. But the bill stalled in the Senate, frustrating scientists who believe the nation that unleashed the nuclear age is obligated to never stop trying to fully comprehend its long-term impact.