Campisi A, Gulino M, Acquaviva R, Bellia P, Raciti G, Grasso R, Musumeci F, Vanella A, Triglia A. Reactive oxygen species levels and DNA fragmentation on astrocytes in primary culture after acute exposure to low intensity microwave electromagnetic field. Neurosci Lett. Feb 12, 2010. Ahead of print.
Exposure to electromagnetic radiofrequencies (EMFs) through the every day use of microwave ovens, wireless networks, and cellular phones, has raised public concerns about long term effects on brain cells. The brain uses electrical activity to send and receive messages and it would be logical to assume that electrical and frequency impulses from whatever source would change brain cell activity. Research studies have already shown that brain cells are sensitive to chronic exposure to EMFs. However, few studies have investigated effects of short single bursts of low EMF exposure. This paper investigates the reaction of brain cells following acute EMF exposure.
The objective of this study was to determine the acute non-thermal effects of EMF exposure on brain cells.
The brain cells used in this study were isolated from neonatal rats, placed in a Petri dish, and incubated for 2 weeks before the experiment began. Three different experimental conditions were employed corresponding to three groups of cells: control, test and sham. The control group was left in the incubator during the entire experiment. The test and sham groups were placed in identical covered water baths at 370C. Cells within the test group were exposed to either non-modulated 900 MHz continuous waves or modulated 900 MHz continuous waves at 50Hz in amplitude. Three different time points (5, 10 and 20 minutes) of exposure were used for different groups of cells within this experimental group. The sham group of cells were not exposed to any radiation. The researchers compared cell viability, stress response, and DNA damage for each group of cells to see whether single short-term exposure to EMFs resulted in verifiable differences.
The authors found that stress levels were different in cells that were exposed to 20 minutes of modulated 900MHz continuous waves. The authors found that these cells also had significantly more damage to their DNA than the other cells, damage that could not be attributed to thermal effects.
Interpretation and Limitations
The authors believe that acute low intensity irradiation can be harmful to brain cells and interfere with the normal development of brain cells. The frequency that was given to the rat cells was four times lower than the established public exposure limit set by the International Commission on Non-Ionizing Radiation Protection (ICNIRP). Due to their results, current existing safety standards should be reinvestigated. The limitation of this study is that there are differences among species and there could be many balancing mechanisms in place in the natural brain environment that could reverse the effects of short single radiation exposure. Still, it is better to err on the side of caution when it comes to issues of public health.
This study demonstrated for the first time that acute exposure of modulated EMF can cause a stress reaction and DNA damage in brain cells.