When I first met Dr. Thomas F. Mancuso in the fall of 1977, he was poring over computer print-outs in his small, cluttered, L-shaped office at the University of Pittsburgh.

Spry, with a trim mustache and horn-rimmed glasses, Mancuso’s passion for data collection often compelled him to bring his work home. Despite his efforts to transform his spacious home into a research archive, Mancuso’s wife Rae kept the place spotless. Occasionally, data would be strewn on the dining room table, but most of the records were kept in dozens of filing cabinets in the basement like a highly guarded treasure.

Since 1945, he had mastered the art of assembling millions of bits of information into groundbreaking studies to determine long-term workplace health hazards. Before his pioneering research, “the major focus on workplace health dealt with on-the-job injuries,” said Bernard Goldstein, Dean of the Pittsburgh University School of Public Health, in 2004. Mancuso “developed techniques to look at the long-term health effects of working.”

Having given away his car to one of his children several years before, the bespectacled physician walked every day to his office in the somber Graduate School building, often stopping first to attend Catholic Mass. In contrast to his contemplative side, Mancuso’s temper was legendary. But his stubborn quest for perfection was more than offset by his loyalty and kind generosity.

These qualities had served him well over the years, but now they were being sorely tested in a struggle over the effects of ionizing radiation on nuclear workers.

Conflict over his studies was nothing new. But it was the unprecedented ferocity of the latest assault against his research that surprised him. Now as he approached the closing years of his illustrious career, Mancuso had not expected that his tedious sorting of statistics would put him at odds with the U.S. nuclear weapons program, one of the most powerful scientific establishments in the world.

Although high-ranking officials were aware of potentially serious health risks to workers and were urged by its advisors to conduct health studies, the Atomic Energy Commission did not initiate occupational epidemiological research until Mancuso was awarded a research contract in 1965.

By that time, Mancuso had established himself as a highly respected figure in the field of occupational epidemiology. While serving as chief of the Ohio Division of Industrial Hygiene between 1945 and 1962, Mancuso published a series of ground-breaking studies showing the toxicological and carcinogenic effects of cadmium, manganese, mercury, hydrogen sulfide, asbestos, aromatic amines, and chromate.

With the encouragement of his mentor Wilhelm Huper at the National Cancer Institute, Mancuso designed and published the first cohort mortality studies on occupational hazards in the United States. In doing so Mancuso invented a revolutionary methodology: using Social Security death benefit claims. That enabled researchers for the first time to follow exposed workers over the many years necessary to detect latent diseases such as cancer.

Mancuso was also known for his honesty and fierce independence. In March of 1976, Mancuso asked Dr. Alice M. Stewart and George Kneale, her statistician from the University of Birmingham in England, to analyze his data.

Dr. Stewart, a member of Mancuso’s advisory committee, was internationally recognized as establishing the link between fetal x-rays and childhood cancers. Since 1955, when she and her colleagues first reported this finding, Stewart had constructed one of the world’s largest epidemiological studies of low dose ionizing radiation, the Oxford Survey of Childhood Cancers.

By the summer of 1976, Mancuso Stewart and Kneale produced a cohort analysis based on 3,710 deaths among Hanford workers collected up to 1973. They found that radiation-induced cancer appeared to be about 10 times greater than current protection standards assumed. As soon as the analysis was finalized, Mancuso and his colleagues briefed the Energy Department in October 1976. “They were clearly unhappy,” Mancuso said. “They urged us not to publish… My job in their eyes was simply to transfer the data to them.”

By the fall of 1977, Mancuso’s research funds had run out. A subsequent Congressional investigation found that Mancuso was fired by DOE under false pretenses after receiving high marks by his contract reviewers.

In November he published his paper in Health Physics, creating a firestorm of controversy. Though he continued to draw a salary from the University of Pittsburgh, Mancuso had no funds with which to continue his research. So Mancuso cut into his personal retirement money to continue working on the Hanford study. Meanwhile the DOE persisted in its attempts to take the data away from him — and most disturbingly, to destroy data Mancuso had collected.

Despite the difficulty in obtaining funding, Mancuso, Stewart, and Kneale persisted in their updated research and publications in the scientific literature. By 1990, the Three Mile Island Public Health Fund, established as part of a legal settlement resulting from the Three Mile Island nuclear accident in 1979, funded their continued work.

The contract with Dr. Mancuso was in a sense a failed experiment by the federal nuclear program to enter the mainstream of public health. Most importantly, the Mancuso contract deviated from standard practices established by the nuclear weapons program in which a system of “in-house” contractors whose existence depended primarily on the federal nuclear program was fostered deliberately.

In 1990, in direct response to pressure by Senator John Glenn (D-OH), DOE entered into a formal agreement with the Department of Health and Human Services to manage and conduct DOE worker health studies. These studies were obscured from public attention and went unappreciated. But all told, workers at 14 DOE nuclear weapons facilities were subsequently found to have increased risks of dying from various cancers and nonmalignant diseases.

In December 2000, the United States enacted the Energy Employee Occupational Illness Program Compensation Act. The law represents the first time any nation has officially acknowledged that its workers were harmed from the production of nuclear weapons. It also established an entitlement program to compensate workers and their survivors. People who worked at over 300 facilities in the United States can file for compensation.

This unprecedented law would not have been possible without the pioneering work of Dr. Thomas F. Mancuso, who passed away on July 7, 2004 at the age of 92.

This story comes from our collection, Bob Alvarez: Lessons From a Lifetime of Activism.

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