The California Department of Public Health (CDPH) has issued a warning against the hazards of cellphone radiation and asked people to decrease their use of these devices and suggests people keep their distance from the devices when possible.
Techcrunch.com reported CDPH director Dr Karen Smith as saying, ''Although the science is still evolving, there are concerns among some public health professionals and members of the public regarding long-term, high use exposure to the energy emitted by cell phones.''
The warning follows findings from a 2009 department document, published after an order from the Sacramento Superior Court.
Last year, University of California at Berkeley professor Joel Moskowitz initiated a lawsuit to get the department to release the findings after he started studying whether the use of mobile phones increased the risk of tumours.
Though a draft of the document was released in March, the final release is more extensive.
''The cellphone manufacturers want you to keep a minimum distance away from your body and you should find out what that distance is,'' Moskowitz told local news station KCRA, shortly after the draft release. ''If you keep the device by your body you will exceed the safety limits provided by the FCC.''
Meanwhile, Geoffrey Kabat, a cancer epidemiologist at the Albert Einstein College of Medicine and the author of Getting Risk Right: Understanding the Science of Elusive Health Risks wrote in Fortune, "The use of the word radiation is wrong and designed to instill fear." He said though the electromagnetic spectrum is a continuum, the word ''radiation'' is generally used to refer to ''ionizing radiation.''
Ionizing radiation is part of the spectrum that has energies that are high enough to knock an electron out of an atom, causing ionization and possibly inducing cancer. UV radiation, X-rays, and cosmic rays are ionizing radiation he writes.
In contrast, cell phone emissions are in the range between radio waves and microwaves and have energies that are many orders of magnitude lower than ionizing radiation.
He wrote that ''it is disingenuous for the Department of Public Health to refer to the public's concerns about the safety of cell phones and to then go on to issue guidelines, which themselves instill fear, while tacitly acknowledging that there is no strong scientific support for concern.''