Are mobile phones harmful?

There is increasing public interest in health risks of mobile phone use. Al though there is a vast body of material on the biological effects of radiof requency fields, current risk assessment is still limited. The article desc ribes several hypotheses and results of biological effects such as thermal effect, genetic and carcinogenic effects and cancer related investigations. Mobile phones transmit and receive waves of frequencies mainly at 800-1800 MHz. Findings on the thermal effect of acute exposure to radiofrequency fi elds were consistent, resulting in an increase of cellular, tissue or body temperature by 1 degreesC or more. Guidelines for risk limits are based on this thermal effect. Experimental investigation suggests that radiofrequenc y fields are nor tumor initiators and that if they art: related to carcinog enicity. this would be by tumor promotion or by increasing the uptake of ca rcinogens in cells. Implications of these experimental results on public he alth concerns are yet unclear. Few epidemiological studies are available on the use of mobile phones or on the radiofrequency exposure and the develop ment of cancer. Most of these studies have no or little quantitative exposu re data and they are limited by the small number of observations. Large epi demiological studies are necessary in order to investigate the use of mobil e phones on the development of cancer. It should be emphasized that even a small elevated risk may have a large implication for public health. as the use of mobile phones and the exposure is rapidly increasing.