Less than 1% of A-bomb survivors recognized as suffering from ”A-bomb diseases”

by Kazuo Yabui, Senior Staff Writer

The range of “A-bomb diseases” recognized by the Japanese government is criticized as too narrow by Hibakusha organizations and scientists. Hibakusha have filed multiple lawsuits in Japan, demanding that the government expand the scope of the criteria involved in certifying the health concerns of A-bomb survivors. They argue that the current criteria ignore the effects of residual radiation and internal exposure to radiation. To date, the government has lost a series of six cases in district courts. How this matter will be resolved is a significant political challenge for 2008, 63 years after the bombing. The emergence of this issue at this late stage is partly due to the fact that the impact of the bomb’s radiation has never been fully clarified.

After World War II, the Japanese government neglected to provide adequate relief measures to hibakusha for many years. Only in 1957, 12 years after the war, was the initial Atomic Bomb Medical Relief Law enacted to grant financial support for the survivors’ medical expenses. Then, in 1968, another provision, Special Measures for Atomic Bomb Survivors, was passed to improve this assistance. Finally, in 1994, marking the 49th anniversary of the bombing, public opinion swayed lawmakers to unify and expand the relief measures contained in the first two laws including the removal of an income ceiling for receiving various allowances resulting in the current Atomic Bomb Survivors Relief Law.

At present, there are approximately 250,000 hibakusha of Hiroshima and Nagasaki now living in Japan and abroad. Among them, survivors officially recognized to be suffering from radiation-based illnesses (generally known as “A-bomb diseases”) are granted special medical allowances under the certification system. The number of certified hibakusha, however, is less than one percent of the total population of survivors and this has produced strong dissatisfaction due to the strict criteria employed. In 2003, hibakusha organizations filed multiple lawsuits to challenge this certification system leading to the state today in which upwards of 300 survivors are involved in legal proceedings at 15 district courts and six higher courts.

To date, decisions have been handed down at six district courts in Hiroshima, Osaka, Nagoya, Sendai, Tokyo and Kumamoto and in every case the plaintiffs, the hibakusha, have won. Combined with the ruling party’s landslide defeat in the upper house election of July 2007, former Prime Minister Shinzo Abe had no choice but to bow to the pressure of public opinion and state that the government would review the certification criteria when he attended the Peace Memorial Ceremony in Hiroshima on August 6th.

Much attention has been paid to how the guidelines for certification would be revised. In December 2007, an expert panel of the Ministry of Health, Labor, and Welfare compiled a draft with revisions to the original criteria. However, this draft used the same concept of “probability of cause” found in the current system. As the district court rulings against the government had all questioned the scientific validity of the certification criteria based on “probability of cause,” hibakusha organizations reacted to this panel’s work with sharp criticism.

Meanwhile, the ruling coalition parties, the Liberal Democratic Party and New Komeito Party, have also demonstrated their intention to reassess the guidelines and the panel charged with this task has drafted a revision that avoids the concept of “probability of cause” and proposes a wider scope for the certification criteria. This draft has been submitted to Prime Minister Yasuo Fukuda and his decision will be an important item on the political agenda in early 2008.

There are differing opinions among experts in Japan and even in Hiroshima on the nature of determining whether illness in hibakusha can be traced back to the atomic bombing. Although epidemiological studies show a higher incidence of cancer among hibakusha, science cannot yet identify the cause in every case and proving that the cancer is the result of exposure to the atomic bomb’s radiation is very difficult. This is the reality of the limits of current scientific knowledge. At the same time, other radiation-related matters await further clarification, including internal exposure and the effects of residual radiation.

Despite the fact that the health repercussions of the atomic bombing are still not fully understood, what stance will Prime Minister Fukuda take? Aging hibakusha are anxious to hear his position.


residual radiation
While “initial radiation” is the radiation released at the time of nuclear fission, “residual radiation” includes 1) radiation from uranium and other fissile materials that did not undergo fission and 2) “induced radiation” emitted from soil and other materials that became radioactive after being exposed to initial radiation.

internal exposure
“Internal exposure” refers to radiation within the body, caused by eating, drinking, or inhaling radioactive particles. Radioactive particles may also enter into the bloodstream through a wound.

certification of A-bomb diseases and “probability of cause”
When an A-bomb survivor, holding an official “Atomic Bomb Survivor’s Certificate” issued by the government, falls ill with cancer, leukemia, or another ailment and the Ministry of Health, Labor, and Welfare certifies that the disease is an “A-bomb disease,” the survivor is provided with a special medical allowance of 137,000 yen per month. During the screening process to certify this disease, the concept of “probability of cause” is used. This means that the probability of the disease having been caused by radiation is calculated according to a formula which takes into account the estimated dose at the distance from the hypocenter and the hibakusha’s age and gender. If the probability is calculated at more than 50%, it is thought that radiation exposure is the likely cause of the illness; however, a probability of less than 10% is judged to have a less influential effect. Hibakusha organizations argue that the screening process is based solely on the initial level of radiation at the time of the explosion and that the effects of residual radiation, including radioactive fallout and induced radiation, are underestimated. They call for correction of the certification system, including 1) rescinding the current guidelines based on “probability of cause” and 2) eliminating the screening process for “A-bomb diseases.”