An evaluation of the mutagenic, carcinogenic and teratogenic potential of microwaves.

A notable proportion of the population is exposed to an increasing number of devices emitting microwaves, a form of non-ionizing electromagnetic radiation in the range 300-30000 mHz. The activation energy of microwave radiations is too small to directly modify any chemical bonds in the irradiated matter. At microwave frequencies the macroscopic dielectric properties of tissues are strongly determined by their water content. Tissues like muscle, brain, skin, with a high water content, have higher permittivity and conductivity values than bone or fat with low water contents. Owing to the energy transfer, to living tissues, by a dipolar relaxation mechanism of water molecules, the penetration of microwaves is limited and one observes a fast and very efficient heat-loss production. A review of the available literature shows that most results on the mutagenicity of microwaves are negative or can often be explained by a temperature enhancement. If microwaves are apparently unable to damage DNA at sub-thermal exposure levels, some results indicate, however, that they might easily potentiate the damaging action of other DNA antagonist agents such as UV or chemicals.