Radiation Effects Research Foundation Research

How many cancers in atomic-bomb survivors are attributable to radiation? from the Radiation Effects Research Foundation FAQ

The Radiation Effects Research Foundation has the primary list of the studies, a series of 13 studies tracking the health of the survivors of Hiroshima and Nagasaki.

Technical Report No. 24-02 Studies of mortality of atomic bomb survivors. Report 13: Solid cancer and noncancer disease mortality: 1950-1997

This continues the series of general reports on mortality in the cohort of atomic bomb survivors followed up by the Radiation Effects Research Foundation. This cohort includes 86,572 people with individual dose estimates, 60% of whom have doses of at least 5 mSv. We consider mortality for solid cancer and for noncancer diseases with 7 additional years of follow-up. There have been 9,335 deaths from solid cancer and 31,881 deaths from noncancer diseases during the 47-year follow-up. Of these, 19% of the solid cancer and 15% of the noncancer deaths occurred during the latest 7 years. We estimate that about 440 (5%) of the solid cancer deaths and 250 (0.8%) of the noncancer deaths were associated with the radiation exposure.

The excess solid cancer risks appear to be linear in dose even for doses in the 0 to 150-mSv range. While excess rates for radiation-related cancers increase throughout the study period, a new finding is that relative risks decline with increasing attained age, as well as being highest for those exposed as children as noted previously. A useful representative value is that for those exposed at age 30 the solid cancer risk is elevated by 47% per sievert at age 70. There is no significant city difference in either the relative or absolute excess solid cancer risk. Site-specific analyses highlight the difficulties, and need for caution, in distinguishing between site-specific relative risks. These analyses also provide insight into the difficulties in interpretation and generalization of LSS estimates of age-at-exposure effects. The evidence for radiation effects on noncancer mortality remains strong, with risks elevated by about 14% per sievert during the last 30 years of follow-up. Statistically significant increases are seen for heart disease, stroke, digestive diseases, and respiratory diseases. The noncancer data are consistent with some non-linearity in the dose response owing to the substantial uncertainties in the data. There is no direct evidence of radiation effects for doses less than about 0.5 Sv. While there are no statistically significant variations in noncancer relative risks with age, age at exposure, or sex, the estimated effects are comparable to those seen for cancer. Lifetime risk summaries are used to examine uncertainties of the LSS noncancer disease findings.

Other radiation health studies are listed.

Radiation health effects are detailed

As of 2007, about 40% of the RERF study population was still living, and more than 90% of the survivors exposed under the age of 10 were still living.

As of 2007, the average age of the RERF study participants was 74 years.

What health effects have been seen among the children born to atomic-bomb survivors?

One of the earliest concerns in the aftermath of the atomic bombings was how radiation might affect the children of survivors. Efforts to detect genetic effects began in the late 1940s and continue. Thus far, no evidence of increased genetic effects has been found. This does not necessarily mean that no effects exist because some past studies were limited in their ability to detect genetic damage.

Recent advances in molecular biology make it possible to evaluate genetic effects at the gene (DNA) level. RERF scientists are preserving blood samples that can be used for such studies.

Monitoring of deaths and cancer incidence in the children of survivors continues, and a clinical health survey was undertaken for the first time during 2002 to 2006 to evaluate potential effects of parental radiation exposure on late-onset lifestyle diseases. To date, there is no radiation-related excess of disease in adulthood, but it will require several more decades to fully determine this, as this population is still relatively young.

If you liked this article, please give it a quick review on ycombinator or StumbleUpon. Thanks