Facts of LifeHow safe are microwave ovens? [Archives:2005/853/Health]

June 23 2005

By Dr. Khaled alNsour
For the Yemen Times

Microwaves used in microwave ovens oscillate at 2450 million cycles per second (MHz), which could be considered safely within the NON-ionizing region. However, it is important to note: Although microwaves do not carry enough energy to be ionizing, they can be dangerous. Non-ionizing radiation is very different from Ionizing radiation . Ionizing radiation is extraordinarily high in frequency (millions of trillions of cycles per second). It is, therefore, extremely powerful and penetrating. Even at low levels, ionizing radiation can damage the cells of living tissue. In fact, these dangerous rays, have enough energy and intensity to actually change (ionize) the molecular structure of matter. In sufficient doses, ionizing radiation can even cause genetic mutations. As shown on the frequency spectrum, the ionizing range of frequencies includes X-rays, gamma rays, and cosmic rays. Ionizing radiation is the sort of radiation we associate with radioactive substances like uranium, radium, and the fall-out from atomic and thermonuclear explosions.

Non-ionizing radiation is very different. Because of the lower frequencies and reduced energy, it does not have the same damaging and cumulative properties as ionizing radiation. Microwave radiation (at 2450 MHz) is non-ionizing, and in sufficient intensity will simply cause the molecules in matter to vibrate, thereby causing friction, which produces the heat that cooks the food.

If microwaves can cook a piece of beef, these waves will also have the same effect on human tissue if it is exposed to high enough intensities for a long enough period of time. Certain body organs are particularly sensitive to this thermal effect. “Thermal”” means heat. Thus