Magnetic Field Exposure and Cancer: Questions and Answers

Source: National Cancer Institute http://www.cancer.gov/cancertopics/factshe...magnetic-fields

Key Points

* Electric and magnetic fields (EMF) are areas of energy that surround any electrical device. EMFs are produced by power lines, electrical wiring, and appliances (see Question 1).

* Electric fields are easily shielded or weakened by walls and other objects, whereas magnetic fields are not. Since magnetic fields are more likely to penetrate the body, they are the component of EMFs that are usually studied in relation to cancer (see Question 1).

* Overall, there is limited evidence that magnetic fields cause childhood leukemia, and there is inadequate evidence that these magnetic fields cause other cancers in children (see Question 2).

* Studies of magnetic field exposure from power lines and electric blankets in adults show little evidence of an association with leukemia, brain tumors, or breast cancer (see Question 3).

* Past studies of occupational magnetic field exposure in adults showed very small increases in leukemia and brain tumors. However, more recent, well-conducted studies have shown inconsistent associations with leukemia, brain tumors, and breast cancer (see Question 4).

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Added on July 10, 2011, 6:06 pmCell Phones and Cancer Risk

Source: National Cancer Institute http://www.cancer.gov/cancertopics/factsheet/Risk/cellphones

Key Points

* Cell phones emit radiofrequency energy. Concerns have been raised that this energy from cell phones may pose a cancer risk to users (see Question 1).

* Radiofrequency energy is a form of non-ionizing electromagnetic radiation; exposure depends upon the technology of the phone, distance between the phone’s antenna and the user, the extent and type of use, and distance of the user from base stations (see Question 2).

* Researchers are studying tumors of the brain and central nervous system and other sites of the head and neck because cell phones are typically held next to the head when used (see Question 3).

* Research studies have not shown a consistent link between cell phone use and cancer. A large international study (Interphone) published in 2010 found that, overall, cell phone users are at lower risk for two of the most common types of brain tumor—glioma and meningioma―compared to non-users. For the small proportion of study participants who reported the most total time on cell phone calls, there was some increased risk of glioma, but the researchers considered this finding inconclusive (see Question 3).

* Further research is needed to investigate possible health effects in children and persons who have used cell phones heavily for many years.

This post has been edited by Power Lines: Jul 10 2011, 06:06 PM