The current debate over the health hazards of mobile phones is a continuation of the debate over the health hazards of weak electromagnetic fields in the entire frequency spectrum that began in the 1950s.

The first experiment on the biological effects of electromagnetic fields dates from the end of the 19th century when Russian scientist Danilevsky observed effects of radio-frequency fields on a muscle preparation that included the nerve supplying the muscle. Investigations peaked simultaneously with the development of radar between 1930 and 1940 but ended abruptly with World War II.

Interest in the subject was rekindled by the discovery that animals and plants failed to thrive and even died in areas exposed to radio waves beyond a certain minimum power density; and also by complaints of workers at radar stations. Research resumed in the 1950s in the former Soviet Union and the United States, as well as in Poland, Italy, and later, Britain.

Public debate over the health hazards of electromagnetic fields began in the United States. In 1973, biologist Robert Becker was approached by the U.S. Navy Commander Paul Tyler to serve on a panel of experts to evaluate some experiments that the Navy had funded. These were in connection with an antenna system the Navy was planning to build in northern Wisconsin that involved grids of buried wires that would extend over thousands of square miles of land. It was to be used for communication with submerged submarines.

Because of the large size of the antenna system, and fears that the non-ionizing electromagnetic radiation (NIEMR) it would emit, might have impacts on health and the environment, Congress had ordered the Navy to carry out the studies.

The New York Academy of Sciences had sponsored a conference on "Electrically Mediated Growth Mechanisms in Living Systems," and Becker had delivered a brilliant keynote paper that summarized his work up to then, which revealed how electrical fields and currents produced by the body are controlling growth and regeneration. By the 1960s, Becker had already proposed a theory that an electrical communication system exists within all living things, and also showed that externally applied fields could influence the processes of growth and regeneration.

But Becker was also worried about the undesirable, harmful effects that could come from exposures to external electromagnetic fields that were often orders of magnitude stronger than the fields within the living body. He had taken on a graduate student, Andrew Marino, to conduct some studies on mice and rats.

Marino had indeed found that animals exposed to NIEMR suffered adverse effects when Becker was asked to review the studies that the Navy had funded.

There were seven scientists on the panel reviewing more than 30 studies. Nearly two-thirds of the studies had found biological effects from exposure to NIEMR; and these were in a variety of species, including slime-mould, rats, birds and humans. The upshot was that all the panel members thought the proposed antenna was a potential hazard to human health, and they drew up a long list of recommendations and further studies.