The study included more than 28,000 workers at 99 utility companies in Denmark.
The researchers included Christoffer Johansen, MD, of the Danish Cancer Society's Institute of Cancer Epidemiology in Copenhagen, Denmark.
They used Danish medical records to track new cases of leukemia, breast cancer, or brain cancer among the utility workers over nearly 23 years, on average.
Johansen's team noted whether the workers had normal, medium, or high levels of on-the-job exposure to electromagnetic fields.
The researchers found "no compelling evidence" of links between cancer and the workers' exposure to electromagnetic fields.
The vast majority of the workers didn't develop leukemia, brain cancer, or breast cancer during the study period.
On-the-job exposure to electromagnetic fields apparently didn't affect cancer risk in the 70 men who developed leukemia, the 188 women who developed breast cancer, and the 110 men and women who developed brain cancer, the study shows. Since there were so few cases of women who developed leukemia and men who developed breast cancer, the researchers did not include them in the study analysis.
"The results do not support the hypothesis of an association between occupational exposure to magnetic fields in the electric utility industry and risks for leukemia, brain cancer, and breast cancer," write the researchers.
Their findings appear in Occupational and Environmental Medicine.
By Miranda Hitti
Reviewed by Louise Chang
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