Magnetism could damage the brain

Exposure to devices that emit low-level magnetic fields, such as those created by hair dryers or electric razors, could damage brain DNA, according to scientists at the University of Washington.

Research also found that the damage created from brief exposure builds up over time.

Rats exposed to a 60Hz field for 24 hours showed significant DNA damage, and rats exposed for 48 hours showed even more breaks in brain cell DNA strands. The exposure also led to an increase in brain cell apoptosis - the process where a cell self-destructs because it is unable to repair itself.

The study builds on previous research and the combined findings show that the intensity of exposure can be as damaging as duration.

Henry Lai, a university research professor, and Narendra Singh, a fellow university bioengineer, both conducted the study. They believe that exposure to magnetic fields upsets the balance of iron in certain cells, creating an increase of free iron in the cell. This free iron undergoes a chemical reaction, which releases "free radicals" – charged atoms that attack cell structures such as DNA, lipids and proteins.

The scientists gave some of the rats drugs, either to neutralise free radicals or decrease free iron before exposing them to the magnetic field. As predicted, the drugs practically blocked the damaging effects. This implies that certain cells with higher iron content, such as brain cells, may be more vulnerable to damage caused by electromagnetism.

Lai does not want people to be alarmed at the findings, but he does urge some caution when electrical items are used, at least until further research is conducted.

"People should do what they can to limit their exposure to as little as possible," he said, "especially in relation to electrical appliances that are used very close to the body."

The study will be published in Environmental Health Perspectives, a journal of the National Institute of Environmental Health Sciences. It can also be accessed on the internet, at http://ehp.niehs.nih.gov/docs/2004/6355/abstract.html.