DNA DAMAGE IN HUMAN BLOOD
Cancers, like all tumors are the result of genetic damage. Most often that damage includes the formation of micronuclei--fragments of chromosomes that form membranes around themselves and appear under a microscope as additional nuclei in blood cells (which normally have one nucleus). The relationship between micronuclei and cancer is so strong that doctors around the world test for their presence to identify patients who are likely to develop cancer. The presence of micronuclei indicates that cells can no longer properly repair broken DNA. This deficiency is considered to be an indication of an increased risk for developing cancer.
- In December 1998, Drs. Ray Tice and Graham Hook of Integrated Laboratory Systems in North Carolina showed that blood cells exposed to cell phone radiation suffered genetic damage in the form of micronuclei. In their studies, DNA and chromosome damage in human white blood cells occurred when exposed to signals from all types of phones - including analog, digital, and PCS. Damage happened even from signals occurring at levels that were below the government's "safety" guideline.
- In 2000, using different methods, Tice and Hook's finding was confirmed by Dr. Joseph Roti Roti of Washington University in St. Louis. Roti Roti's research showed that human blood cells exposed to radiation at wireless phone frequencies did indeed develop genetic damage, in the form of micronuclei. This finding received a lot of notice because Dr. Roti Roti is a prominent scientist whose work is funded by Motorola Inc.
Tice and Hook and Roti Roti's findings have very serious implications. If cell phone radiation encourages the formation of micronuclei in blood cells, and micronuclei are said to be "biological markers" for cancer, then based on these studies alone, cell phone use could be said to increase one's risk of developing cancer.
BREAKDOWN IN THE BLOOD-BRAIN BARRIER
The blood-brain barrier is a special filter in the blood vessels of the brain that keeps dangerous chemicals from reaching sensitive brain tissue and causing DNA breaks and other damage.
- In 1994 and again in 2002, Dr. Leif Salford from Lund University in Stockholm, Sweden found in his studies that rats exposed to cell phone radiation showed a breakdown in the blood-brain barrier, as well as areas of shrunken, damaged neurons.
The micronuclei studies of Tice and Hook and Roti Roti and the blood-brain findings of Salford provide a two-step explanation for how cancer could be caused by cell phone radiation.
Step One: A leakage or breakdown in the blood brain barrier provides a pathway for cancer-causing chemicals in the bloodstream (from tobacco, pesticides, air pollution, etc.) to leak into the brain and damage sensitive brain tissue that would otherwise be protected. These chemicals could break the DNA in the brain or cause other harm to those cells.
Step Two: While a number of studies show that cell phone radiation by itself does not appear to damage DNA, the micronuclei findings suggest cell phon radiation does impair the DNA repair mechanisms normally found in brain cells. Micronuclei result from a breakdown of the cell's ability to repair itself. If the brain cells are unable to repair themselves, then carcinogenesis-- the creation of tumors-- induced by chemical toxins-- could begin.
DNA carries the genetic material of an organism and its different cells. Any damage that goes unrepaired affects the future generation of cells. The change is then procreated and this mutation is seen as a possible cause of cancer.
TUMORS FOUND IN PEOPLE WHO USE CELL PHONES
Epidemiological studies performed by different investigators using different methods show some evidence of an increased risk of developing tumors by people who use cellular phones.
- In 1998, Dr. Ken Rothman of Eidemiology Resources, Inc. in Newton, Mass., did a study that showed that handheld cell phones users have more than twice the risk of dying from brain cancer than do car phone users--whose antennas are mounted on the body of their car and far removed from the users' heads.
- Also in 1998, Joshua Muscat, a research scientist from the American Health Foundation, did a study that showed a doubling of the risk of developing neuro-epithelial tumors on the outside of the brain among cell phone users, particularly on the side of the skull where cell phone antennas are held during calls.
- In another study, Muscat also showed in another study that people who have used cell phones for six years or more have a 50 percent increased risk of developing acoustic neuroma, a benign tumor of the nerve that controls hearing and extends from the ear to the brain. Acoustic neuromas can cause hearing loss and can be life-threatening if untreated.
Muscat's finding were confirmed in a separate study in Stockholm, Sweden by Anders Ahlbom in 2004, whose study was sponsored by the World Health Organization (WHO). Anhbom found that that people who have used cell phones, this time for at least 10 years- may have an increased risk of developing acoustic neuroma.
- In a study also requested by WHO, researchers lead by Dr. Lennart Hardell of the Orebro Medical Center in Sweden examined 1,617 patients aged between 20 to 80 who had been diagnosed with a brain tumour between 1997 and 2000. They were then compared to healthy people. Those who used cell phones for less than 10 years faced a 20% higher risk of developing brain cancer. But for those who used cell phones for more than a decade the risk was 80% higher. The study also found that tumours were 2.5 times more likely to be on the same side of the head as the phone was held. Cancers of the auditory nerve, acoustic neuromas, showed an even greater increased risk-- 3.5 times greater.
CELL PHONE RADIATION DOSAGE AND RESPONSE
All studies mentioned above showed that an increase in cell phone radiation exposure also increases the likelihood an adverse effect.
In Repacholi's study of mice, risk of lymphoma increased significantly the longer the mice were exposed to the radio waves.
In the research work of Tice and Hook, and Roti Roti, the risks of genetic damage as measured by micronuclei formation, increased as the amount of radiation increased.
In the three epidemiological studies-- two by Muscat and one by Hardell-- the risk of tumors was greater in the areas of the brain near where the cell phone was held.
In Salford's study, the higher the radiation exposure level to the rats, the more damage was apparent in the blood vessels in their brains and the neurons.
THE BIG CANCER PICTURE
The test tube studies by Tice and Hook; the mouse study by Repacholoi and Salford; and the epidemiological studies by Rothman, Muscat, and Hardell all agree in that they suggest an increased risk of cancer among cell phone users. These studies fit together to form the beginnings of a picture that everyone can see. They perhaps don't form the complete picture yet, but there is enough evidence already in place to see that there is cause for genuine public health concern about cell phone usage and safety.
According to Dr. Carlo, "The big picture is disturbingly clear. There is a definite risk that the radiation plume that emanates from a cell phone antenna can cause cancer and other health problems. It is a risk that affects hundreds of millions of people around the world. It is a risk that must be seen and understood by all who use cell phones so they can take all the appropriate and available steps to protect themselves-- and especially to protect young children whose skulls are still growing and who are the most vulnerable to the risks of radiation." |
