Though technologic developments bring social and economic benefits to the society, the health consequences of these are difficult to predict and manage. With rapid advances in electromagnetic field (EMF) technologies and communications, children are increasingly exposed to EMFs at an earlier age. Due to an association between childhood leukemia and exposure to extremely low frequency (ELF) magnetic fields they are classified as a "possible human carcinogen." Concerns about the potential vulnerability of children to radio frequency (RF) fields have been raised, as their developing nervous systems are more susceptible. In addition, their brain tissue is more conductive, RF penetration is greater relative to head size, and they will have a longer lifetime of exposure than adults.
To evaluate information relevant to children's sensitivity to ELF and RF EMFs, the World Health Organization held an expert workshop in Istanbul, Turkey, in June 2004. A recent article, published in the August issue of Pediatrics, is based on discussions from the workshop, and suggests that the exposure to toxic agents with mutagenic and carcinogenic potential, such as ionizing radiation, cancer chemotherapeutic drugs, and some chemicals, poses risks for the induction or progression of cancer during embryonic and childhood development. Ionizing radiation given at large doses is one of the few known risk factors for childhood leukemia and brain cancer. Radio and television broadcasts, mobile phones and base stations, and other communications infrastructure produce RF fields. The evidence that induced electric fields might affect development of the nervous system and other tissue was discussed at the workshop in some detail. On the other hand, exposure to RF radiation induces heating in body tissues and imposes a heat load on the whole body. Hyperthermia during pregnancy can cause embryonic death, abortion, growth retardation, and developmental defects; animal studies indicate that the development of the CNS is especially susceptible.
AdvertisementRegarding the long-term health effects of mobile-phone use, it is suggested that low-cost precautionary measures are appropriate, especially because some of the exposures are close to guideline limits. Children's RF exposure can be reduced by restricting the length of calls or by using hands-free devices to keep mobile phones away from the head and body.
Because of widespread use of mobile phones and relatively high exposures to the brain among children and adolescents, investigation of the potential effects of RF fields on cognition and the development of childhood brain tumors was considered particularly urgent. The article concludes with a recommendation for additional research and the development of precautionary policies in the face of scientific uncertainty.