Those who argue that overhead power lines cause cancer received a boost of support recently when the California Public Utilities Commission (CPUC) released the results of an eight-year study into the effects of electromagnetic fields (EMF). Conducted in Great Britain and San Francisco, the study suggests that EMF produced by overhead power lines increase the risk of cancer in children and the incidence of miscarriage in pregnant women.

Although the full report isn’t expected to be released to the public for a few months, details of its findings began circulating in late August when a leaked copy of it surfaced on an online news site. According to information that has been released and confirmed, however, the study claims that EMF increases the risk of childhood leukemia, adult brain cancer, and amyotrophic lateral sclerosis, or Lou Gehrig’s disease.

Despite the study’s findings, Prof. Philip Walton, who specializes in applied physics at the National University of Ireland, Galway, claims the risk of childhood leukemia caused by overhead power lines is minimal, pointing out that EMF could only be linked to two cases of leukemia per year, on average. Walton cited the results of a major study conducted in Britain.

The researchers responsible for the CPUC study stand behind their findings. “In Britain, hundreds of thousands of homes are exposed to [EMF] levels that mean they could be at risk,” says Dr. Raymond Neutra of the California Department of Health Services.