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Date of last update: 10/21/2017.

Forum Name: Miscellaneous Cancer Topics

Question: health concern about strong magnets' effects

 vandelay - Wed Nov 30, 2005 7:17 am


first of all thank you for taking the time to read my post; I have a medical question regarding potentially harmful effects of strong (electro-) magnetic fields.

I'm thinking of buying, as a present to my brother, a device used for doing magic tricks, called "The Bat" (there's also a very similar one called "M5"), which relies on the diamagnetic phenomenon to lift (levitate) certain objects, using very strong magnets, -- from what I understand, similar to the magnets sold here: -- magnets that are worn on the inside of one's sleeves.

I know strong electro-magnetic fields can increase the risk of cancer (like with prolonged use of cell phones for example), and also I imagine intuitively that such fields (induced by natural magnets or by other technical means) can be harmful in other ways too; on the other hand, I know that certain magnets are used in cancer treatment, and so, since obviously I'm concerned not to do any harm with my present, I would like to ask if there is really any danger involved in using such a strong magnet, close to one's body.

Anticipated thanks for your advice!

Tudor :)
 vandelay - Mon Dec 12, 2005 2:14 pm


is anybody even checking these forums to see if there are any questions that deserve to be answered? I'd even settle with a "yes, but your question is of no general interest" kind of answer, that still would be more polite that totally ignoring a question, even though electro-magnetic radiation effect on cancer is most definitely a topic that a lot of people are interested in.

Thank you...
 Dr. A. De la Guerra - Tue Dec 13, 2005 11:12 pm

User avatar Hi vandelay,

Before talking about Electro Magnetic Fields (EMF) and cancer risk I will like to define some terms. Electric fields are created by differences in voltage: the higher the voltage, the stronger will be the resultant field. Magnetic fields are created when electric current flows: the greater the current, the stronger the magnetic field. An electric field will exist even when there is no current flowing. If current does flow, the strength of the magnetic field will vary with power consumption but the electric field strength will be constant. The term “Electro Magnetic Field” (EMF) usually refers to electric and magnetic fields at extremely low frequencies such as those associated with the use of electric power.

All known cancer-inducing agents, including radiation, certain chemicals and a few viruses, act by breaking chemical bonds, mutating DNA. The nature of the interaction of biological material with an electromagnetic source depends on the frequency of the source. Both electric and magnetic fields are present around appliances and power lines. However, electric fields are easily shielded or weakened by walls and other objects, whereas magnetic fields can pass through buildings, humans, and most other materials. Since magnetic fields are most likely to penetrate the body, they are the component of EMFs that are usually studied in relation to cancer.

Many people fear that EMFs cause cancer; however, a causal connection between EMFs and cancer has not been established. The National Research Council (NRC) spent more than three years reviewing more than 500 scientific studies that had been conducted over a 20-year period and found "no conclusive and consistent evidence" that electromagnetic fields harm humans. The research has not shown in any convincing way that electromagnetic fields common in homes can cause health problems, and extensive laboratory tests have not shown that EMFs can damage the cell in a way that is harmful to human health.

Some epidemiology studies have shown an increased risk for childhood leukemia in association with EMF. This association is difficult to interpret in the absence of reproducible laboratory evidence or a scientific explanation that links magnetic fields with childhood leukemia. 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. 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. 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.

The World Health Organization scientists reported that the epidemiological studies "do not provide sufficient evidence to support an association between extremely-low-frequency magnetic-field exposure and adult cancers, pregnancy outcome, or neurobehavioural disorders."

All the above is true for extremely-low-frequency magnetic-field exposure (to which we are habitually exposed).

The magnet you want to buy is a Neodymium permanent magnet. Permanent magnets are made of ferromagnetic materials which have the ability to "remember" the magnetic fields they have been subjected to. Neodymium magnets are actually made up of a compound called NIB, for Neodymium Iron Boron (Nd2Fe14B). This compound is one of the strongest known ferromagnetic materials. I have not found any study linking exposure to magnetic-field energy of permanent magnets to cancer. Eventhough, I strongly suggest you to read the Magnet Safety Warnings in the disclaimer’s page of the link you provided ( You can see there are serious issues when handling these products (from losing and eye to death).

Hope you find the information useful.

Dr Torax.
 vandelay - Wed Dec 14, 2005 8:07 am

Hi! Thank you for your kind and well-documented response. It is useful information, and I really appreciate it!

All the best!

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