Study: EMF, Suicide Risk Linked

Wednesday, 15 March 2000
R A L E I G H , N .C . (AP)

CHRONIC EXPOSURE to low-frequency electromagnetic fields may be responsible for a higher suicide risk among electric utility workers, according to researchers at the University of North Carolina at Chapel Hill.

While unable to prove that exposure causes suicide, researchers found electricians for five U.S. power companies had twice the suicide rate and linemen 1 1/2 times the rate of utility workers not employed in those jobs.

The findings appeared Wednesday in the April issue of Occupational and Environmental Medicine.

The researchers studied about 6,000 men who were part of a larger group of about 139,000 employed as utility workers between 1950 and 1986. Research involving the larger study group has shown that some workers exposed to high magnetic fields have elevated cancer rates, but not that EMF exposure causes cancer.

One explanation for the possible link between exposure and suicide is that electromagnetic fields are thought to suppress melatonin levels in the body, said Edwin van Wijngaarden, a doctoral student and lead author of the UNC study.

"The EMF-cancer link is pretty controversial," van Wijngaarden said. "This may also be controversial, but at least there is a more plausible biological mechanism involved."

Melatonin, a hormone produced by the pineal gland deep in the brain, is thought to play a key role in a person's sleep cycle and mood.

"There does seem to be a link between melatonin levels and depression," said study co-author David Savitz, a professor and chair of epidemiology at UNC.

Researchers said it isn't known exactly how electromagnetic fields might inhibit melatonin production.

Daniel Kripke, a California researcher who has studied the relationship between EMFs in the home and melatonin levels, said he had not seen the UNC study but questioned the role that melatonin might play.

"This is an area where there is a lot of speculation," he said.

A 1996 study by Canadian researchers found no link between suicide and EMF exposure. But Savitz said the UNC study was significantly larger than the Canadian study of workers at a Quebec utility company.

Van Wijngaarden said the results of the study may not be applicable to the general population because the study group was so selective.

UNC researchers looked at data compiled over several years from employees of Carolina Power & Light Co., Pacific Gas & Electric, PECO Energy Co. (formerly Philadelphia Electric Co.), Virginia Electric Power Co. and the Tennessee Valley Authority.

Van Wijngaarden and his colleagues found 536 suicides among the group between 1950 and 1986 and compared them to a control group of 5,348 non-suicides of the same race and age.

Suicide is the eighth leading cause of death in the United States; 30,000 people took their lives in 1997.