Hiroshima Researchers Aid Soviets in Studying the Legacy of Chernobyl

Scientists have begun to consider whether the lessons of the world’s first nuclear holocaust will be of value in coping with the consequences of history’s worst nuclear power plant accident.

At a cluster of drab buildings on a hillside overlooking the thriving city center that once was ground zero, American and Japanese researchers who have studied the legacy of Hiroshima for four decades are now examining the legacy of Chernobyl.

Recently, a blood specialist, two radiologists and a military hospital doctor from the Soviet Union visited Japan to seek advice on the reactor disaster of last April, huddling with other scientists and chatting with the stooped, elderly victims of the atomic bomb.

They found more empathy than comfort. Chernobyl, they were told, presents a task of monumental proportions.

‘Costs Enormous’

“They will have to be very well prepared,” said Dr. Itsuzo Shigematsu, chairman of the Radiation Effects Research Foundation, the world’s primary study center on the long-term toll of radiation exposure. “The costs will be enormous.”

When fire swept the reactor in the Ukraine, it unleashed clouds of radiation that caused 31 deaths, 200 serious injuries and forced resettlement of 135,000 people, all presumably exposed to low-level radiation.

Because medicine is powerless to reverse the effects of ionizing radiation, which causes subtle changes in cells that may only become evident years later, Western experts estimate that Chernobyl could cause about 5,000 more cancer deaths than would otherwise have occurred.

But the full effects will not be known for decades--and not without a widespread monitoring program.

Japan Studies Incomplete

In Japan, studies are still incomplete on hibakusha, or victims of the Aug. 6, 1945, U.S. atomic bombing of Hiroshima and the bombing three days later of Nagasaki. More than 365,000 people have registered as victims, but several thousand more still come forward each year.

The Soviet team said that it plans a comprehensive study of Chernobyl, both the small group seriously hurt--most of them nuclear plant workers suffering burns or radiation sickness--and of those who received low-level radiation doses.

But in public discussions and private conversations, they left a blurry impression of whether Moscow is ready to commit to a program of that scope.

“The people who were not at the site at the time received such insignificant doses that it will take us many years to see deviations in them,” Andrei Vorobjev, the Soviet delegation leader, said. “And these will be so insignificant that it will be hard to see if they are connected with radiation.

“There are so many scientific problems involved in this accident that require a great deal of research input, but little output. I’m afraid my kids will be doing it, not me.”

Japan, U.S. Effort

At the radiation foundation, where 300 staff members work with a $25-million annual budget supplied equally by the Japanese and U.S. governments, studies of 121,000 victims have proved that exposure increases leukemia beginning about five years afterward and that certain solid-tumor cancers begin 10 to 30 years later.

They also demonstrated that fetuses exposed at 7 to 15 weeks in the womb ran an increased risk of being retarded--something that may already be showing up in the Soviet Union.

“There seems to be a specific time when the embryo is very sensitive,” said Dr. Charles W. Edington, a former U.S. Department of Energy official who is now one of the foundation’s three American directors.

2 Major Obstacles

The Soviets, Edington said, face two major obstacles in measuring the long-term human effects: enrolling a study group and estimating how much radiation each victim received.

The Soviet physicians acknowledged that they have just begun to register the 135,000 victims. They also will need an equal number of people not exposed as a measuring group for comparison, meaning a program eventually involving more than 250,000 people.

But in Japan, many hibakusha refused to come forward for years. Bomb victims were seen as social outcasts and unsuitable marriage partners, even though no proof was found of genetic mutations in their children.

Using recent advances in dosimetry, foundation scientists last year revised downward their estimates of Hiroshima and Nagasaki radiation doses--meaning that the radiation was more dangerous than previously believed.

‘You Have to Estimate’

“You have to estimate all this,” Edington said. “When something like the bomb or Chernobyl happens, you’re not out there measuring everything.”

He said that radiation estimates had two components: external exposure, doses affected by buildings, weather and other conditions, and internal exposure, the effects of ingesting irradiated dust, water or food. The internal exposure at Chernobyl will prove more difficult to assess, he said.

The Hiroshima bomb, an air burst detonated about 600 yards above ground, drew up little from the ground and dumped fallout only in isolated areas. The Chernobyl fire, however, spewed vast quantities of radioactive dust and smoke.

Along with the long-term technical issues, the Soviets may also have to come to grips even sooner with the accident’s psychological fallout.

‘Constant Fear’

One visiting physician, Anatoli Tsyb, a radiology laboratory director, hinted at the problem’s dimensions when he said that the widespread effects of Chernobyl so far had been limited to complaints of stress among the thousands resettled.

“All survivors live in the constant fear that any sickness may turn out to be atomic bomb disease,” wrote Naomi Shohno, a Hiroshima nuclear physicist and himself a bomb survivor, in the recent book “Hibakusha.” “Though there is no scientific basis for such an assumption, survivors cannot help feeling that this disease is lurking within them.

“Whenever survivors fall ill, they are haunted by the fear of death.”