No abstract

There is considerable uncertainty of the potential biological effects of extremely low frequency magnetic fields (ELF-MF or EMF) because of mixed results in epidemiological and laboratory studies. In the present study, exponentially growing human-hamster hybrid A(L) cells were treated with a 100 microT alternating EMF powered at 60 Hz for either 24 h or 7 days. Exposure to EMF was conducted either alone or in combination with graded doses of a physical or chemical carcinogen. gamma-radiation was chosen as a form of ionizing radiation while N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) was chosen as a form of chemical contaminant. Exposure of A(L) cells to EMF alone for a period up to 7 days was non-cytotoxic and non-mutagenic. Concurrent EMF treatment did not increase either the cytotoxicity or induction of CD59- mutants by graded doses of gamma-rays or MNNG in A(L) cells. This study shows conclusively that short-term or long-term exposure to EMF alone neither affects the survival of A(L) cells nor increases the mutagenic potency of other environmental carcinogens.

were not measured, instead 'wire codes' were generally used There is considerable uncertainty of the potential as a surrogate for magnetic fields (6). Furthermore, the biological effects of extremely low frequency magnetic association of residential EMF exposure and risk of cancer fields (ELF-MF or EMF) because of mixed results in induction is not consistent across epidemiology studies. epidemiological and laboratory studies. In the present Although a number of residential studies have reported an study, exponentially growing human-hamster hybrid A L increase in risk of childhood leukemia, several other cells were treated with a 100 µT alternating EMF powered investigations have showed no positive correlation (7-9). at 60 Hz for either 24 h or 7 days. Exposure to EMF wasOccupational EMF exposure has also heightened concern conducted either alone or in combination with graded due to the fact that such exposure indices are much greater than doses of a physical or chemical carcinogen. γ-radiation was residential exposure, and because of the growing population of chosen as a form of ionizing radiation while N-methyl-NЈ-