It was in September 1975 that Dr. Alice Stewart, a 68-year-old British epidemiologist, first saw statistical evidence that radiation was killing workers at the Hanford nuclear weapons plant in Washington State.
She was astonished. It was the first time researchers had found elevated levels of cancer in weapons workers exposed to low levels of radiation.
”It came at me all of a sudden that what we were going to say would shock the world,” she said in a recent interview. ”Not even I had thought that the effect of such a small dose on an adult would be as great as it was.”
Stewart and two colleagues published the finding, which was based on government-funded research, in the journal Health Physics in 1977. It drew immediate and vitriolic criticism from other scientists, many of them under contract to the weapons industry.
That study and the ensuing furor drew Stewart into a long struggle with the American government and its nuclear weapons industry. For 14 years, this exquisitely courteous British scientist, now 83, battled a policy of scientific secrecy that she said threatened the lives of thousands of workers in weapons plants and of people living near them.
Even before the Hanford finding was published, the government cut off funds for the study, prompting a Congressional committee to investigate allegations of a scientific cover-up.
In March, in a change in policy on research and radiation protection that goes to the heart of Stewart`s criticism, Energy Secretary James D. Watkins said he would open records on worker health that the government has long kept secret.
Watkins also said he would end the Energy Department`s control of the government`s most important program for studying the effects of radiation on workers in the weapons industry; by August, he said, the Department of Health and Human Services would manage the studies.
Those orders strengthened Stewart`s reputation as perhaps the Energy Department`s most influential and feared scientific critic, and they enhanced her credibility as the leading technical expert on worker safety for the department`s opponents in Congress and for citizen groups.
”When I first started in this area, I didn`t know what a nuclear reprocessing plant was,” she said in an interview in Denver, where she was testifying at a worker`s compensation hearing on behalf of a widow who said her husband had died from exposure to radiation at the nearby Rocky Flats weapons plant.
”I have formulated views since then on the strength of my data. And that is, this industry is a great deal more dangerous than you are being told.”
Her conclusions about the hazards of low-level radiation are by no means shared by all experts, particularly in the Department of Energy. Among her most ardent critics is Dr. Shirley A. Fry, the leader of the department`s epidemiology group at the Oak Ridge atomic weapons plant in Tennessee.
”The data do not support such statements,” said Fry, whose group may be substantially changed by Watkins` orders. ”Dr. Stewart`s work has been widely criticized for technical problems.”
But with increasing frequency, scientists in and out of the government have been confirming Stewart`s views about the dangers of low-level radiation. Last December, in the most authoritative affirmation yet of her theories, the National Academy of Sciences said low-level radiation was a much more potent carcinogen than it had reported nine years before.
Alice Mary Stewart was born in 1906 in Sheffield, England, the third of eight children in a prominent family of British physicians.
Her father, Dr. Albert Ernest Naish, was an internist and professor of medicine at Sheffield University. Her mother, Lucy Wellburn Naish, taught anatomy at the university and was among the first British women to become a doctor.
Educated at Cambridge University, Alice was one of four Naish children to follow her parents into medicine. Her daughter now is a physician, too.
Her career in epidemiology, a science that marries traditional diagnostic skills with statistics, began soon after she joined the faculty of Oxford University in 1941.
In a study sponsored by the British government, she concluded that exposure to TNT impaired factory workers` ability to form blood and led Britain to change its manufacturing procedures and equipment.
Though she was regarded as one of Britain`s best and most creative epidemiologists, she was unknown abroad until 1956, when she first tangled with the atomic power industry over low-level radiation.
That year, in a letter to The Lancet, the British medical journal, Stewart reported on a disturbing finding she had made about prenatal X-rays:
children who had died of cancer in England from 1953 to 1955 had received twice as many X-rays before birth as those without cancer.
It was the first time low levels of radiation had been shown to have any effect on health, and the finding was met with outrage from physicians and the nuclear power industry. They rejected the idea that millions of people might be at risk not only from a common medical procedure, but also from radiation produced by the nuclear power and weapons industries.
Scientists had known that high doses of radiation could cause illnesses;
a dose of 500 rems or more, comparable to the levels received by some rescuers in the Chernobyl nuclear accident in 1986, was fatal. But what was the biological effect of doses of 1 rem or lower? And was there any danger from years of exposure to low levels of radiation? In the 1950s, scientists agreed that there was not.
By the mid-1970s, Stewart`s findings had been duplicated by other scientists, and the conclusion that X-rays were hazardous to unborn children had gained worldwide acceptance.
”We benefited from all the opposition, really,” Stewart said recently.
”If everybody accepted the finding we laid out in the 1950s, we`d have no reason to go on and collect more and more data. We shouldn`t know one-quarter of what we know now.”
Stewart retired from Oxford in 1974; she is now a senior research fellow at the University of Birmingham in the English Midlands. In 1975, she was asked by Thomas Mancuso, a researcher at the University of Pittsburgh, to help in a study for the Atomic Energy Commission of workers at the Hanford Reservation.
A few days after Easter that year, she arrived in Pittsburgh with her collaborator George W. Kneale, a statistician. By the fall, it was clear to the three researchers that Hanford workers exposed to radiation levels less than half the federal safety limit of 5 rems a year suffered from at least a third more than the expected levels of pancreatic cancer, lung cancer and multiple myeloma, a rare bone marrow cancer.
”We knew this was going to be inflammatory,” she said. ”I persuaded Mancuso that he must warn his people. It wouldn`t be fair to spring this on them. What I never counted on was their opposition.”
In early 1976, Mancuso presented preliminary results to the Atomic Energy Commission, the predecessor of the Energy Department. That March, the AEC notified him that his 13-year research grant had been terminated.
In Congressional hearings in 1978, government officials denied that he had been dismissed because of the cancer findings, and later made public an inspector general`s report that said the dismissal was not improper.
But Rep. Paul Rogers of Florida, the chairman of the House subcommittee that looked into the incident, disputed the inspector general`s conclusion.
”We regret that the shortcomings with the report may only fuel charges of `cover-up` already voiced,” he wrote in a letter to James R. Schlesinger, secretary of the newly formed Department of Energy, in August 1978.
At hearings in 1988 and 1989, she told Senate and House committees that the Energy Department`s program for assessing radiation hazards at nuclear weapons plants was badly flawed, hindering the free exchange of scientific ideas.
First, she argued, it was scientifically indefensible for the department to lock in its own files the medical records of 600,000 American nuclear weapons employees that had been collected by the government since the industry started in 1942.
Those records, she said, were the best source of raw data on the effects of low-level radiation; yet they were available only to researchers under contract to the Energy Department.
Second, Stewart argued for a halt to what she called a troubling conflict of interest in American radiation research. Not only was the Energy Department the owner and operator of the vast weapons industry, she said at a Senate hearing last August, but it was also the government`s principal source of funds to study the health effects of radiation.
In March, facing growing Congressional pressure and public embarrassment, the department moved to address both problems. The studies of health effects would be taken over by the Health and Human Services Department, Watkins said, and the secret medical records would be made available to independent scientists as quickly as possible, though he declined to set a date.
The first of the independent scientists to receive the material will be Alice Stewart, as principal investigator for the Three Mile Island Public Health Fund, a private group in Pennsylvania that studies the effects of radiation.
”Many times I`ve been asked why I didn`t follow my friends into quiet retirement,” she said. ”If I was a coward and afraid of my job, I wouldn`t say a thing. But I am retired. I have no department that anybody`s dependent upon for work. I speak out because I think there are not a lot of people in such a good position. I have nothing to lose. A lot of people do. This area of research can be shut down. I`ve watched it happen.”
