LOS ANGELES -- Dr. John W. Gofman, the medical physicist whose fight for what he considered scientific honesty in understanding the health effects of ionizing radiation made him a pariah to the nuclear power industry and the US government, died of heart failure Aug. 15 at his home in San Francisco. He was 88.

Often called the father of the antinuclear movement, Dr. Gofman and his colleague at Lawrence Livermore National Laboratory, Arthur R. Tamplin, developed data in 1969 showing that the risk from low doses of radiation was 20 times higher than stated by the government .

Their publication of the data, despite strong efforts to censor it, led them to lose virtually all of their research funding and, eventually, their positions at the government laboratory.

Most of their conclusions were subsequently have been validated, but critics say the risks have been ignored by an electric power industry that sees nuclear energy as a pollution-free alternative to fossil fuels and by a medical industry that continues to use much larger amounts of radiation for medical tests than are required.

"He always stood up for the integrity of science," said Charles Weiner, professor emeritus of the history of science at the Massachusetts Institute of Technology.

"He was really an original voice" in the debate over the risks of nuclear power, Weiner said, "someone who was an insider in nuclear weapons production who was very highly regarded by leaders in the field... and who brought credential, credibility, and authority."

Until his death, Dr. Gofman continued to argue that there is no safe level of exposure to ionizing radiation.

"Licensing a nuclear power plant is, in my view, licensing random premeditated murder," Dr. Gofman said in the 1982 book "Nuclear Witnesses: Insiders Speak Out."

"First of all, when you license a plant, you know what you are doing -- so it's premeditated. You can't say, 'I didn't know.' Second, the evidence on radiation-producing cancer is beyond doubt.... It's not a question anymore: Radiation produces cancer, and the evidence is good all the way down to the lowest doses."

Dr. Gofman and Tamplin's data about the health effects of radiation -- and their revelations about the Atomic Energy Commission's attempts to silence them -- played a large role in the demise of that organization in 1974.

The Atomic Energy Commission was divided into two organizations: the Energy Research and Development Administration, whose goal was to promote the development of atomic energy, and the Nuclear Regulatory Commission, which was supposed to monitor the safety of the nuclear industry.

Dr. Gofman argued, however, that the changes were merely cosmetic and that the Nuclear Regulatory Commission continued to promote nuclear power to the detriment of the public at large.Continued...

In 1971, he helped found the Committee for Nuclear Responsibility, a San Francisco-based advocacy group that studies the health effects of ionizing radiation.

More recently, Dr. Gofman had argued forcefully that radiation is overused in medicine, both for diagnosis and treatment, without a full consideration of the risks. He noted that some hospitals use as much as 100 times the required radiation for imaging. He also argued that CT scans are used too often when less dangerous approaches are available.

John William Gofman was born Sept. 21, 1918, in Cleveland, the son of Russian immigrants. After finishing high school during the Great Depression, he attended nearby Oberlin College.

After graduating, he enrolled in medical school at Cleveland's Western Reserve University. After a year, however, he took a leave of absence and enrolled in the chemistry program at the University of California, Berkeley.

Upon his arrival there, he met with future Nobel laureate Glenn Seaborg, who suggested that he might examine whether uranium-233 could exist in nature.

Intrigued, Dr. Gofman signed on, and he and his colleagues produced four one-millionths of a gram of the isotope in the Berkeley cyclotron and proved that it would fission spontaneously.

He was also the codiscoverer of protactinium-232, uranium-232, and protactinium-233 during his graduate student years.

In 1942, physicist J. Robert Oppenheimer, who headed the Manhattan Project, came to Dr. Gofman and told him that half a milligram of plutonium was needed immediately for crucial experiments that would determine the future direction of the project.

Dr. Gofman and his colleagues packed a ton of uranyl nitrate around the Berkeley cyclotron and irradiated it with neutrons day and night for six weeks. Then, working with 10-pound batches of the uranium, the team spent three weeks working around the clock to isolate half a cubic centimeter of liquid containing 1.2 milligrams of plutonium -- twice as much as they had expected.

Despite his later antinuclear stance, Dr. Gofman said, he had no guilt about his role in the development of the atomic bomb, citing the "human monstrosity" of Germany's Nazi regime.

After his work on plutonium was completed, Dr. Gofman returned to medical school at University of California at San Francisco. He earned his medical degree in 1946.

Dr. Gofman taught at Berkeley and UC San Francisco.

Dr. Gofman shifted his research to study trace elements in human biochemistry. But, in 1962, John Foster, director of Lawrence Livermore National Laboratory, invited him to set up a radiation biology laboratory there.

With a budget of $3 million a year, he began studying potential hazards of radiation but immediately began butting heads with Washington bureaucrats. He retired formally in 1973 and spent the rest of his career writing books about the risks of medical radiation and continuing his research on nuclear hazards.

Dr. Gofman leaves a son, John D. Gofman, an ophthalmologist, of Bellevue, Wash.

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