cell phone addiction

tema sull'uso inapropriato dei telefoni cellulari scritto in lingua inglese (1 pagine formato doc)

Appunto di fadis
Study Links Cell Phones To Brain Cancer Risk Study Links Cell Phones To Brain Cancer Risk   Concerns have been raised about whether cell phone use can be linked to the development of brain tumors.
Now, a study from Swedish researchers provides evidence backing the claim. Researchers at the Karolinska Institute in Stockholm, Sweden, based their findings on questionnaire and interview data obtained from 209 persons with brain tumors and 425 healthy control subjects. In a 2-year study, the team found an increased risk in anatomical areas of the brain exposed to microwaves during a mobile phone call. This risk holds even when statistical adjustments are made for other risk factors including ionizing radiation and laboratory exposures.
The researcher pointed out, however, that most of the people in the study used the older analog system, which gives two to three times higher exposure than the digital system, which is now mostly used -- at least in Europe. Larger studies are necessary to make firm conclusions. The investigators have a much larger brain tumor study ongoing with about 1,500 incident patients and 1,500 controls and the results are expected within one year. In light of their current findings, the authors offer several suggestions about cell phone usage. Use an earpiece to reduce exposure to the brain and, in a car, use an external fixed antenna. Otherwise, your exposure to microwaves might even be higher than using the phone outside the car. In addition, extended conversations should be conducted on a regular corded telephone. Insofar as children are concerned, since the developing brain might be more sensitive to microwaves, children's exposure should be limited. One useful tip is to find out the specific absorption rate (SAR) value of various cell phone types. The SAR may differ by as much as a factor of 20 between different brands. Depending on how close the cell phone antenna is to the head, as much as 60 percent of the microwave radiation is absorbed by and actually penetrates the area around the head, some reaching an inch to an inch-and-a-half into the brain. This is the first generation that has put relatively high-powered transmitters against the head, day after day. The cell phone industry says every phone it sells is safe and meets government radiation safety limits German investigators report that exposure to electromagnetic fields during mobile phone use may increase resting blood pressure. Exposure of the right hemisphere to a radio-frequency electromagnetic field for 35 min causes an increase in sympathetic efferent activity with increases in resting blood pressure between 5 and 10 mm Hg, most likely due to more pronounced vasoconstriction. The pulsed high-frequency electromagnetic fields emitted by cellular phones can affect response patterns of human brain activity. German investigators found that electromagnetic fields emitted by cellular phones could "...alter distinct aspects of the brain electrical response during an