Steady exposure to the electromagnetic radiation given off by cellphones during use may disrupt fetal development, disturb memory and weaken the barrier that protects the brain from environmental toxins, says a welter of new research being presented this week in Istanbul, Turkey.

The authors of the studies, published in the past two years, highly preliminary and conducted on rabbits, mice and rats, suggested that the non-ionizing radiation emitted by cellphones and the base stations that broadcast cellphone signals may fundamentally damage cells by means other than the heat that they generate. That is a highly controversial assertion, because scientists have asserted that the only kind of radiation that causes cancer and DNA damage is ionizing radiation such as that emitted by nuclear material. The microwave radiation emitted by working cellphones simply does not have the power to scramble DNA or disrupt cell function, they say.

The studies were conducted by scientists working under the umbrella of the Environmental Health Trust, a nonprofit organization devoted to identifying and controlling environmental health risks. The EHT has been especially active in showing that non-ionizing radiation emitted by cellphones is damaging to humans.

In one of the studies reviewed in Istanbul, mice exposed to two hours per day of radio frequency emissions from a transmitting cellphone were less able to to learn and rerun mazes, suggesting that cellphone radiation might impair spatial memory -- the kind of recall that helps us navigate  from place to place. A second study found that the barrier between bloodstream and brain that protects the latter from most toxins became more permeable when male rats (although not females) were exposed to 20 minutes of radio frequency radiation such as that emitted by cellphones. A third study found that exposing pregnant and non-pregnant rabbits to six minutes a day of electromagnetic radiation led to the release of "secondary messengers, such as free radicals," which in turn destroyed DNA and fat molecules. (The babies born after such exposures, however, were fine).

The Istanbul meeting, convened by the Environmental Health Trust and Gazi University, comes a day before the International Agency for Research on Cancer -- an agency of the World Health Organization -- is to meet to decide whether research has demonstrated that radio frequency electromagnetic fields emitted by mobile phones are potentially cancer-causing. The agency has overseen a 10-year, $14-million epidemiological study called the Interphone Study Group, an international consortium of researchers that set out to determine whether cellphone use is linked to increased rates of gliomas or meningiomas (both forms of brain cancer), parotid gland cancer or cancer of the acoustic nerve.

The Interphone Study Group's findings, released in May 2010, failed to establish that mobile phone use raises an individual's risk for any of the cancers. But after the international effort turned up a troubling but ambiguous signal that brain cancer was more common among the heaviest cellphone users they surveyed, the group decided further research on the subject was "merited." 

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