|Cell phone radiation danger|
MAN: "I use my phone all the time. I'm always on my phone."
WOMAN: "It's kind of pretty much important to me because it's like my life saver."
WOMAN: "I need my cellphone."
So far, no studies have proven beyond question that the radio signals from cellphones cause brain cancer or other health problems. But a new study by government scientists in the United States has some people wondering what to think.
The scientists found that holding a cellphone to your ear for at least fifty minutes increases brain cell activity. Even the scientists themselves are not sure about the meaning of their findings.
Dr. Nora Volkow led the study. She heads the National Institute on Drug Abuse, part of the National Institutes of Health. Dr. Volkow says she would not be concerned that fifty minutes of cellphone exposure would harm anyone. But she says the research does show the need to study whether or there are long-lasting effects of repeated exposure over several years.
Her team studied forty-seven healthy volunteers between January and December of two thousand nine. The volunteers had cellphones placed against both ears while the scientists made images of their brain activity.
As part of the test, one phone was activated but muted for fifty minutes. The other phone was off. After that, the people were tested with both phones turned off. Dr. Volkow says the brain scans showed increased activity in brain cells closest to the activated phone.
NORA VOLKOW: "This right area of the brain that was very close to the antenna shows the largest increase in metabolism as compared when the telephones were off. Even though the radio frequencies that are emitted from current cellphone technologies are very weak, they are able to activate the human brain to have an effect.''
The scans showed how the brain cells used sugar to produce energy, a normal activity. The activity was seven percent higher in areas of the brain closest to the cellphone antenna.
The study appeared in the Journal of the American Medical Association.
Experts say people who are concerned about mobile phones can take steps like using a wired headset.
Dr. Giuseppe Esposito is a nuclear medicine expert at Georgetown University Medical Center in Washington. He says after many years of studies, better kinds of research are still needed to settle questions about cellphone safety. These studies would take years.
GIUSEPPE ESPOSITO: "We need what are called epidemiological studies where you will follow a population using cellphones -- high users or light users -- and then see what happens over the years."
Contributing: Jessica Berman and Vidushi Sinha
Source: VOA Special English (http://www.voanews.com/learningenglish/)
exposure - the condition of being subject to some effect or influence
metabolism - the process that occurs when the body generates energy
radio frequencies - electromagnetic radiation
epidemiological - of or relating to epidemiology (the study of factors affecting the health and illness of populations)
1. What does cellphones do to our brain?
2. If in case cellphones have a bad effect on our health, will you still continue using it?
3. Relating this health issue to heart diseases:It was confirmed that staying in front of the TV or computer for long hours can cause heart diseases (http://www.medicinenet.com/script/main/art.asp?articlekey=124790). Will you still continue doing this?