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In a new paper that is sure to reignite concerns over the safety of
mobile phones, Drs. Leif Salford and Bertil Persson have shown that extremely low doses of GSM radiation can
cause brain damage in rats.
Salford, a neurosurgeon, and Persson, a biophysicist, both at
Sweden's University of Lund, report that they see nerve damage following a single two-hour exposure at a
specific absorption rate (SAR) of 0.002W/Kg. The effect becomes statistically significant at
0.02W/Kg. These non-thermal levels are a hundred to a thousand times lower than the 2W/Kg exposure
standard recommended by the International Commission on Non-Ionizing Radiation Protection (ICNIRP).
Salford and Persson first showed that low-level microwave radiation
can cause leakage through the blood-brain barrier (BBB) over ten years ago (see MWN, J/F92 and J/A92). In
this latest work, they again show that microwave radiation can impair the BBB, but they now add that the
chemicals that leak through the BBB probably damage neurons in the cortex, the hippocampus and the basal ganglia
of the brain. The cortex is close to the surface of the skull, while the basal ganglia are much deeper.
Salford and Persson write that the damaged neurons they observed may
in fact be dead brain cells.
Perhaps their most surprising observation is that leakage through the
BBB was still evident eight weeks after a single two-hour exposure even at these low doses.
Salford and Persson close their paper with this warning:
Neuronal damage of the kind here described may not have immediately
demonstrable consequences, even if repeated. It may, however, in the long run, result in reduced brain
reserve capacity that might be unveiled by other later neuronal disease or even the wear and tear of
aging. We cannot exclude that after some decades of (often) daily use, a whole generation of users may
suffer negative effects may-be already in their middle age.
Salford and Persson exposed three groups of eight rats to digital
915MHz microwaves at 0.002, 0.02 and 0.2W/Kg, and another eight served as controls. They note that, We
realize that our study comprises few animals, but the combined results are highly significant and exhibit a
clear dose-response relationship.
They used enough animals that it would be hard to say that what they
saw is an artifact, said Dr. Henry Lai of the University of Washington, Seattle. Lai has previously
reported that microwaves can cause DNA breaks in the brains of rats (see MWN, N/D94). DNA breaks could
lead to cell death, and this would look like what Salford is reporting, Lai said.
Salford and Persson exposed rats that were 12 to 26 weeks old in
order to simulate the level of development of human mobile-phone-addicted teenagers. The rats were allowed
to live on for about 50 days after their exposures before they were sacrificed and their brains examined.
Dr. Yngve Hamnerius of Chalmers University of Technology in Goteborg,
Sweden, had suggested this delay before examining the rats brains. Some 20 years ago, he and other
researchers at Chalmers found damage in the brains of rabbits that had been exposed to pulsed microwaves similar
to those from radar for one hour a day for three days. The Chalmers team told the 1984 annual meeting of
the Bioelectromagnetics Society that no acute effects were seen, but that morphological and biochemical changes
became apparent three to four months later.
The implications of this observation were never pursued until
now. People very rarely wait before looking for an effect, Hamnerius told Microwave News. He
believes that Salford and Perssons new work should be taken seriously.
In the summer of 2001, Drs. Pierre Aubineau and Fatma Tre of the
University of Bordeaux reported leakage from blood vessels in the brains of rats, including the BBB, exposed to
non-thermal levels of microwaves (see MWN, N/D01).
The ability of microwaves to cause leakage through the BBB was first
demonstrated by U.S. scientists in the mid-1970s, but research was later cut off by the U.S. military funding
agencies. Over the years, sporadic reports have briefly rekindled interest in the area.
Salford and Perssons own reports of BBB leakage have not been
followed up. For instance, not a single study was undertaken by the U.S. mobile phone industry's six-year
research effort directed by Dr. George Carlo and its lobbying arm, the CTIA.
This is yet another instance in which a long-standing observation has
been ignored for too long, said Dr. Ross Adey, who has been doing brain research for more than 50 years.
Adey is based in Redlands, CA, USA. |
