Study Links Utah Leukemia Deaths to Nuclear Fallout

Fallout from the more than 100 above-ground nuclear weapons tests in Nevada between 1951 and 1958 may have been responsible for a small percentage of the deaths from leukemia in Utah between 1952 and 1981, according to a new study by researchers at the University of Utah and the USC Medical School.

The study, which will be published next week in the Journal of the American Medical Assn., confirms the results of previous studies. Those earlier studies had found an unusually high leukemia rate in southern Utah, thought to be related to the Atomic Energy Commission’s Nevada test site.

But the new results may be more reliable because the researchers have estimated for the first time that dosage of radioactive fallout received by individuals who died of leukemia.

“We believe our current work is the definitive study,” Duncan C. Thomas of the USC Medical School, one of the authors of the study, said in a written statement. “The findings of these earlier studies have been controversial because none was able to quantify the radiation doses received by the leukemia cases.”

The study involved a comparison of 1,177 Utah residents who died of leukemia and 5,330 residents who died of other causes and served as a control group. Residence histories and fallout deposition data provided by the U.S. Department of Energy allowed individual exposure estimates to be prepared. All of the study subjects were Mormons, so that residential histories could be reconstructed using church records.

In Washington County, Utah, nearest the test site, the average dose of radiation to individuals’ bone marrow was highest. Residents of major population centers, such as Salt Lake, Weber, Davis and Utah counties, which are farther away, had lower radiation exposures.