EM fields from cell phone masts can amplify pain
Underwood, an Iraq war veteran, had previously been injured by an improvised explosive device and had his left arm amputated. He reported extreme pain when roaming on his cellphone.
Although there have been anecdotal accounts of neuropathic pain due to radio frequency electromagnetic fields there has been no scientific evidence to support this until now. The evidence is in research conducted by associate professor Mario Romero-Ortega and published online in PLOS ONE in January.
The team worked on the premise that the formation of neuromas – inflamed peripheral nerve bundles that often form due to injury – could be sensitive to radio frequency EMF.
To test this, the team randomly assigned 20 rats into two groups – one receiving a nerve injury simulating amputation, and the other group receiving a sham treatment. Once a week the rats were exposed for 10 minutes to RF EMF at a power density of about 750mW per square meter, equivalent to that at about 39 meters from cellphone tower.
The RF field was circularly polarized at a frequency of 915MHz and energy density of 756 ± 8.5 mW/m2.
Researchers found that by the fourth week, 88 percent of subjects in the nerve-injured group demonstrated a behavioral pain response to the exposure, while only one subject in the other group exhibited pain at any time and that was during the first week.
Previously the accepted wisdom was that neuroma has to be present to evoke pain. But Texas team found that EM fields could produce a pain response prior to neuroma formation.
"Our study provides evidence, for the first time, that subjects exposed to cellphone towers at low, regular levels can actually perceive pain. Our study also points to a specific nerve pathway that may contribute to our main finding," said Romero-Ortega, an associate professor of bioengineering at the university.
The researchers also performed experiments at the cellular level and explored the role of the protein TRPV4, which is known to be a factor in heat sensitivity and allodynia, a condition where light touch is perceived as pain.
"There are people who live in caves because they report themselves to be hypersensitive to RF electromagnetism, yet the rest of the world uses cellphones and does not have a problem. The polarization may allow people to disregard the complaints of the few as psychosomatic,” Professor Romero-Ortega said. "In our study, the subjects with nerve injury were not capable of complex psychosomatic behavior. Their pain was a direct response to man-made radio frequency electromagnetic energy."
The next step is to try and develop devices that block neuropathic pain from RF electromagnetic energy, the research team said.
Bryan Black, a research associate in the Department of Bioengineering in the Jonsson School; Dr. Rafael Granja-Vazquez, a postdoctoral fellow at UT Dallas; Dr. Benjamin Johnston of Brown University; and Dr. Erick Jones Sr., a professor of industrial, manufacturing and systems engineering at UT Arlington, also contributed to the work.
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