High doses of ionizing radiation, such as that released by atomic bombs, are a known cause of leukemia. A new long-term study published in The Lancet Haematology has looked at the rates of leukemia with low-doses of radiation long-term. Researchers looked at data from more than 300,000 workers in France, the United States and the U.K. and found an increased risk of dying from leukemia among those who were exposed to low doses for many years.
The study was led by Dr. Klervi Leraud of the Radiobiology and Epidemiology Department at Fontenay-aux-Roses in Cedex, France. “A lot of epidemiological or radiobiological studies have brought evidence that exposure to ionizing radiation can cause cancer and leukemia,” he said, according to Scientific American. Dr. Leraud also told Scientific American that employees in the U.S., the U.K. or France can seek compensation if they developed leukemia after being exposed to ionizing radiation.
The precise threshhold of low-dose radiation linked to an increased risk of cancer is unknown, Scientific American reports. Researchers found that the workers were exposed to a cumulative dose of 16 milligray (mGy) on average, or one mGy each year, throughout the study. The U.S. Food and Drug Administration (FDA) says exposure for a computed tomography (CT) scan of the lumber spine ranges from one to two mGy.
Researchers monitored radiation exposure in 308,297 nuclear energy workers for an average of 27 years and tracked deaths caused by leukemia and lymphoma. By the end of the study, 531 died due to leukemia and 814 died due to lymphoma. Twenty-two percent of the workers had died by the end of the study. The study found that certain types of leukemia increased with cumulative dose of radiation exposure. The authors of the study note that exposure to radiation has increased on average in the U.S., from 0.5 mGy in 1982 to 3 mGy in 2006.