Dear EarthTalk: What’s the story with electro-magnetic fields? Can you really get cancer from living near clusters of power lines or from sleeping near the fuse box in your house?
—Tim Hutchins, Arcata, CA
Over the past 25 years, there has been growing concern and controversy in the scientific community—and in the public domain—about possible links between electro-magnetic fields (EMFs) and any of several forms of cancer.
EMFs are invisible lines of force that radiate from sources of electricity, including power lines and transformers, interior home wiring and all electrical appliances, gadgets and machinery. These fields have both electric and magnetic components that diminish in strength with distance. The electric segment of the field may be at least partially blocked by physical barriers, such as walls, trees and partitions, but the magnetic segment is much less easily shielded.
In an attempt to clear up concerns and uncertainties about the health effects of EMFs, the federally funded National Institute of Environmental Health Sciences (NIEHS) conducted a multi-million dollar, five-year study of all relevant EMF research during the mid-1990s. Although NIEHS concluded in 1998 that there was still no clear answer to the question of risk, it did affirm that extremely low frequency (ELF) EMFs should be classified as possible human carcinogens in the case of two cancers: childhood leukemia related to residential exposure; and chronic lymphocytic leukemia in adults in occupational settings.
A few years later the World Health Organization concluded, based on studies of childhood leukemia, that ELF magnetic (but not electric) fields were possibly carcinogenic to humans.
But uncertainty remains. One of NIEHS”s key conclusions in 1998 was: “Despite a multitude of studies, there remains considerable debate over what…health effects result from exposure to EMF. There is still no clear answer to the question, “Can exposure to electric and magnetic fields resulting from production, distribution and use of electricity promote cancer or initiate other health problems?”” NIEHS decided there was inadequate evidence to draw any clear conclusions.
But while the evidence of EMFs effects on humans is not conclusive, May Dooley, whose company Enviro Health Environmental Home Inspections provides comprehensive on-site EMF testing, cites several scientific studies showing that EMF exposure has increased the size and number of tumors in laboratory animals. She recommends reducing exposure as much as possible: “If someone with cancer knew that eating a certain food would speed up the growth of tumors, you can bet that he or she wouldn”t eat that food.”
CONTACTS: World Health Organization, www.who.int/peh-emf/en ; National Institute of Environmental Health Sciences (NIEHS), www.niehs.nih.gov/oc/news/emfnew.htm ; Enviro Health Environmental Home Inspections, (888) 735-9649, www.create-your-healthy-home.com .