What Are Electromagnetic Fields?
By Michael R Neuert, MA, BSME, ©2023
Electromagnetic fields (EMFs) are a type of electromagnetic radiation emitted by almost everything electrical or electronic in our modern world. EMF sources include power lines, transformers, electric panels, electrical wiring, computers, lights, clocks, appliances, televisions, hairdryers, cell phones, cordless phones, microwave ovens, Wi-Fi, wireless routers, wireless computer hardware, cell towers, TV/radio broadcast towers, Smart Meters, etc.
Visible light (like that from the sun) is also a type of electromagnetic radiation. The term “electromagnetic field” or “EMF” is usually used to refer to all the electromagnetic radiation frequencies that are lower (slower) than visible light. Scientists also refer to the EMF frequencies as non-ionizing radiation, which means that EMFs are not strong enough to ionize molecules.
In contrast, the electromagnetic radiation frequencies that are higher (faster) than visible light are called “ionizing radiation” — because they have enough energy to disrupt or ionize molecules, and thus are potentially very dangerous to biological organisms. Ionizing radiation includes X-rays and the various nuclear radiations, which are clearly known and accepted as being hazardous to human health.
Can EMFs Really Affect Our Health?
In the beginning, scientists believed that EMFs (non-ionizing radiation) could not affect human health because EMFs cannot ionize molecules in the way that X-rays and nuclear radiation can. But scientists then discovered that EMFs could indeed affect human health by heating up the tissues within our bodies — similar to the way a microwave oven warms up food. So today, most of the international EMF safety standards, such as the FCC limits for the general public in the US, are designed to protect our bodies from these heating effects.
But a growing number of studies are reporting definite biological effects from EMF exposures that are well below the FCC limits and similar thermal standards for EMF safety. It is interesting to note that the FCC actually has a second, much stricter, set of EMF safety standards in place also. These other FCC limits address important concerns about EMFs at levels well below the tissue heating levels — but not for us humans, for our electronics!
“Electromagnetic interference” or “EMI” is a critical concern for electronic devices and systems, because EMFs can cause interference with the operation and function of sensitive electronics. For example, the FCC takes great care in controlling the assignment of EMF frequencies and power outputs for radio stations, television stations, cell towers and all wireless devices, to make sure that the EMF signal from one station or device does not overlap and interfere with the EMF signal or the proper working of another device or station.
Similar to the way that relatively low levels of EMFs can create troublesome interference problems for sensitive electronics, the biological research increasingly suggests that similarly low levels of EMFs — exposures significantly below that needed to heat our body tissues — can interact, influence and interfere with the sensitive “bio-electronics” within our own cells, tissues, brains and bodies.
For example, scientists have discovered that human beings — and almost all animals from whales to worms — have magnetic sensing tissues that can sense the natural magnetic field of the planet. Depending on the species, this magnetic sense is used to orient itself, migrate over vast distances, or even to help regulate important biological functions such as the circadian rhythms for brain activity, digestion and sleep.
In fact, studies show that the human pineal gland can sense daily changes in the Earth’s magnetic field, and uses this information to help regulate our wake/sleep cycles. Researchers have shown that artificial magnetic fields — well below the heating threshold, like those from power lines — can cause a kind of biological EMI and suppress the secretion of melatonin from the pineal gland at night. This is important because melatonin is the main hormone that controls our sleep cycle, as well as a potent natural anti-oxidant that fights cancer within our bodies.
What Kinds of EMFs Are a Concern?
There are three main categories of electromagnetic fields (EMFs) to be concerned about. These three main types are called magnetic fields, electric fields and radio frequency (RF) fields. All three types have been linked to important biological effects in the scientific research studies.
ELF magnetic fields are the EMF component most often linked to serious health effects — such as childhood leukemia and other cancers — in the research studies. Common sources include power lines, electrical wiring, lights, appliances and most other electrical devices. (“ELF” or “extremely-low-frequency” is the scientific name for the EMF frequency range that includes the 60 cycles-per-second electricity commonly used in the US and Canada, and the 50 cycles-per-second electricity used in most other countries.)
ELF electric fields have also been linked to important biological effects, but have been studied less in the research. Anecdotally, they are often involved when people feel sensitive to electromagnetic fields. Electric fields are usually caused by electrical wiring in walls, by nearby power cords for lamps and other devices, and sometimes from overhead power lines. Electric fields induce measurable voltages onto the skin, which are easily detected with a Body Voltage Meter.
Radio frequency (RF) Fields (including microwaves) are commonly used in wireless communications and broadcasting. They have been linked to several kinds of cancer tumors and other health problems. RF fields are emitted from cell towers, cell phones, cordless phones, TV/radio broadcast towers, Smart Meters, Wi-Fi antennas, wireless computers and components, baby monitors, microwave ovens, radar equipment, etc.