Nation’s response could avert crisis like Chernobyl’s
Dr. John Kulig vividly remembers the trip he made to Belarus more than a decade ago to treat children harmed by the Chernobyl nuclear accident. He found himself in a room with 50 teenagers, all bearing the “Chernobyl necklace,’’ a scar at the base of their throats from thyroid cancer treatment.
The Tufts Medical Center pediatrician knows firsthand the potential of a nuclear disaster to cause harm. But he and local radiation specialists say that while the eventual health and environmental impact of the escalating crisis in Japan is uncertain, one thing seems clear: The situation is dramatically different than the Chernobyl reactor explosion 25 years ago, in which a lack of transparency and inaction by the government needlessly exposed many nearby residents to radiation.
“The risk seems real that something significant could happen and there could really be some large-scale radiation contamination in the area,’’ Dr. Harold Swartz, professor of radiology and medicine at Dartmouth Medical School, said of the events in Japan. But, he added, “probably minimal numbers of people would actually be put at risk, just because I think the Japanese are responding very appropriately.’’
The Japanese government has ordered an evacuation of the area around the four damaged reactors, told people to stay indoors, and distributed pills intended to help protect against thyroid cancer.
Radiation exposure has a range of effects on health, but it depends on several factors that are still fuzzy in the evolving situation in Japan, including the type and amount of radiation being released and how it disperses. Some types of radioactive particles are short-lived or give off penetrating radiation that is of less concern because it does not travel very far. Other radioactive particles stick around much longer and emit dangerous, penetrating radiation. For example, if radioactive cesium has been released in large amounts and settles onto land, it could become a health and environmental hazard, because it has a half-life on the order of three decades. The half-life is the amount of time it takes for half of the radioactive atoms to decay.
The most immediate risk is to the workers who are attempting to keep the reactors cool and bring the situation under control. High doses of radiation can kill cells, causing radiation sickness, a slew of acute symptoms that can come on in hours or days. They include nausea, vomiting, burns on the skin, bone marrow destruction, and even death. At Chernobyl, 28 emergency and plant workers died of acute radiation sickness.
What is less predictable is the effect of the radiation exposures that might be sustained by the rest of the population. A well-known health problem is thyroid cancer that can occur, especially in young children and adolescents who breathe in, drink, or eat food contaminated with radioactive iodine. But the Japanese have evacuated the area in a 12.5-mile radius around the plant and are reportedly distributing potassium iodide pills, which are used to block the uptake of radioactive iodine, which causes thyroid cancer.
There have been thousands of cases of thyroid cancer after Chernobyl, but the most widespread long-term health problem has been a rise in mental health problems, according to a United Nations report. Most physicians are hopeful that the steps the Japanese government has taken will avoid such cases.
The situation around Chernobyl was exacerbated because many local people were not alerted to the explosion and were not evacuated right away or given pills, according to Dr. Aleksandr Perepletchikov, a pathologist at St. Elizabeth’s Medical Center who began treating Chernobyl victims five years after the disaster.
“Because you cannot feel radiation, you cannot see radiation,’’ Perepletchikov said. “. . . That’s part of the problem.
“For a week or two weeks after Chernobyl happened, nobody was informed,’’ he said. “People continued to eat, drink . . . Nobody was protected, nobody told it was dangerous to go there.’’
Increased exposure to low levels of radiation is known to increase the risk for cancer, depending on the dose received. Dr. John Boice, a radiation epidemiologist at the Vanderbilt University School of Medicine, who recently returned from Hiroshima, where he is helping to conduct a study of the 86,000 survivors of the atomic bombings in Japan, said that over the past 65 years 10,000 of those people have died of cancer, but just 500 of the deaths are attributed to radiation exposure.
“In every place there’s been a significant radiation event, there’s been an increased risk of damage to bone marrow cells,’’ said Dr. Eva Guinan, associate director of the center for clinical and translational research at Dana-Farber Cancer Institute. “Exactly what is going to happen will depend on the kinds of particles generated, and until we’re a little further into this,’’ it is impossible to know.
That knowledge will also help scientists understand the environmental impact.
After Chernobyl, according to the International Atomic Energy Agency, nearly 60,000 square miles in Belarus, Russia, and Ukraine were contaminated by radioactive fallout. Scientists said that because the prevailing winds in Japan appear to have been blowing out to sea, it could help decrease risk of radiation exposure to people and the risk of fallout on land.
Scientists and physicians said it was important to keep the nuclear problems in perspective.
“As a pediatrician, I’m much more concerned about the terrible effects of the earthquake and the tsunami,’’ said Kulig, director of adolescent medicine at Floating Hospital for Children at Tufts Medical Center.
“It’s all a matter of scope, and right now that really dwarfs the nuclear issue. But it is somewhat sobering to see all these so-called ‘fail-safe’ mechanisms failing.’’
Carolyn Y. Johnson can be reached at firstname.lastname@example.org.