Researchers have found that when exposed to such fields, the drug tamoxifen lost its ability to halt the proliferation of cancer cells grown in the laboratory.
Tamoxifen is a synthetic hormone used to prevent the recurrence of breast cancer.
These findings, reported last week at a Washington, D.C., meeting sponsored by the U.S. Public Health Service, also heighten concern that these electromagnetic fields may be triggering hitherto unrecognized biological changes in people. Though the average magnetic field associated with the 60 hertz current in U.S. homes is 2 mG or lower, it can reach 12 mG in a small share of homes, such as those with unusual electric wiring. Values range as high as 1,000 mG in some occupational settings. People may also be exposed briefly to 12 mG or higher magnetic fields from electric razors and hair dryers, the sides of computer monitors, or appliances with large motors, such as refrigerators. Untreated cells appeared to grow equally well in each field.