Dr. Jim Seward was one of the many presenters at the Oct. 14 joint meeting of the U.S.-Japan Roundtable and the Forum on Energy’s Editorial Board. Seward is a Clinical Professor of Medicine at the University of California San Francisco and a Clinical Professor of Public Health at the University of California Berkeley. He’s lectured extensively on radiation health issues.
According to Seward, the radiation released at the Fukushima Daiichi site is unlikely to significantly increase the risk of cancer among nuclear workers, children or people who eat fish — provided that Japan continues to maintain and monitor its strict regulations regarding radiation. At issue is a debate over the relationship between exposure and cancer risk. At low levels (defined as below 100 millisieverts, or msv) it is not possible to measure how the dosage increases the risk of cancer. Does risk increase incrementally with low levels of exposure or is 100 msv a threshold, below which the risk remains low? In his presentation, Seward discussed evidence from areas of high natural radiation, as well as observable rates of cancer in Fukushima workers, both of which indicate that the risk of cancer remains low.
View his presentation below: