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May 14, 2018 · Microwaves Excite Molecules. Although microwaves have wavelengths too long to be ionizing, the power in microwaves can make them dangerous. Microwaves have wavelengths between .01 and 5 centimeters, much longer than those of visible light. They produce heat by causing certain molecules, like water, to vibrate strongly.
- Overview
- What are EMFs?
- Types of EMF exposure
- Sources of radiation
- Research on harmfulness
- Danger levels
- EMFs in daily life
- Symptoms of EMF exposure
- Protection from EMF exposure
- Takeaway
Electric and magnetic fields occur naturally and also come from human-made sources. Scientists and oversight agencies generally agree that low-frequency EMFs pose little danger to human health.
Most of us are used to the electronic conveniences of modern life. But few of us are aware of the possible health risks presented by the gadgets that make our world work.
Our power lines, cellphones, microwaves, Wi-Fi routers, computers, and other appliances send out a stream of invisible energy waves. Electric and magnetic fields (EMFs) are produced anywhere electricity is used, including at home and in the workplace.
Some experts are concerned about potential health effects from these fields. But should we be worried?
Since the beginning of the universe, the sun has sent out waves that create EMFs, or radiation. At the same time the sun sends out EMFs, we can see its energy radiating out. This is visible light.
At the turn of the 20th century, electric power lines and indoor lighting spread across the world. Scientists realized that the power lines supplying all that energy to the world’s population were sending off EMFs, just like the sun does naturally.
Over the years, scientists learned that many of the emerging electrical appliances also create EMFs. As the medical world advanced, much of its diagnostic and treatment equipment, like imaging devices for X-rays and CT scans, were also found to make EMFs.
Today, 90 percent of the world’s population has access to electricity and uses electrical appliances. That means lots of electricity and EMFs are created around the world.
Radiation exists across what’s called the electromagnetic spectrum. This radiation ranges from very high-energy (called high-frequency) on one end of the spectrum, to very low-energy (or low-frequency) on the other end.
Examples of high-energy radiation include:
•x-rays
•gamma rays
•some higher-energy ultraviolet (UV) rays
This is ionizing radiation, meaning this energy can affect cells on the atomic level by removing an electron from an atom, or “ionizing” it. Ionizing radiation can damage the body’s DNA and cells, which may contribute to genetic mutations and cancer.
Non-ionizing radiation
•microwave ovens •computers •smart meters •wireless (Wi-Fi) routers •cellphones •Bluetooth devices •power lines •MRI machines
Ionizing radiation
•ultraviolet light (UV) radiation. UV radiation comes naturally from the sun, and from man-made sources like tanning beds, phototherapy, and welding torches •X-rays and gamma rays. This type of radiation comes from both natural and human-made sources. Natural sources include radon gas, the earth’s radioactive elements, and cosmic rays that hit the earth from beyond the solar system. Human-made sources include medical X-rays and CT scans and cancer treatment.
There’s disagreement in scientific literature over whether EMFs pose a danger to human health and, if so, how much.
The International Agency for Research on Cancer (IARC) has classified non-ionizing EMFs in the radiofrequency range as Group 2B, a possible human carcinogen. These fields are produced by electronic products like cellphones, smart devices, and tablets.
IARC operates under the World Health Organization (WHO). It convenes working groups of scientists from around the world regularly to evaluate the cancer risks presented to humans by environmental and lifestyle factors.
The current IARC evaluation from 2011 pointed to a possible link between RF radiation and cancer in people, particularly glioma, a malignant type of brain cancer.
This conclusion means that there could be some risk. The report emphasized that the link between cellphone use and cancer risk needs to be carefully monitored by the scientific community. It said more research was needed into long-term, heavy use of mobile phones.
Some researchers feel there’s already enough evidence of harm from long-term, low-level exposure to non-ionizing radiation that the IARC should upgrade the classification to a Group 1, a known carcinogen.
EMF exposure levels are monitored and enforced at the global, national, and local levels in a varied patchwork of procedures by multiple organizations, depending on where you live.
The electric industry in the United Kingdom maintains a database where you can see the widely varied exposure limits and enforcement measures in countries around the world.
Internationally, the primary guidance on radiofrequency EMFs comes from the International Commission on Non-Ionizing Radiation Protection (ICNIRP). It bases its guidelines on its evaluation over many years of peer-reviewed scientific literature concerning health effects from RF EMF exposure.
ICNIRP is a non-governmental organization recognized by the World Health Organization (WHO).
In 2020, WHO updated its international ICNIRP Guidelines for limiting exposure to larger RF electromagnetic fields ranging from 100 KHz (kilohertz) to 300 GH (gigahertz).
The ICNERP guidelines currently specify that people at work shouldn’t be exposed to current electric densities in the body’s head, neck and trunk of greater than 10 mA m-2 (the “basic restriction”).
Electric fields are produced by voltage, and magnetic fields are produced by electric current. Electric fields are measured in V/m (volts per meter). Magnetic fields are measured in µT (microteslas). Both electric and magnetic fields vary in strengths at different times and locations.
Electric fields vary because of differences in the amount of voltage used by various devices. The higher the voltage supplied to a device, the stronger the electric field will be. An electric field exists even when there’s no current flowing.
Magnetic fields are produced by the flow of electric current and therefore vary depending on the strength and amount of the current being used. The more electric current a device uses, the stronger the magnetic field will be.
It might be surprising to learn just how varied magnetic field levels are around products. The strength of a magnetic field may not depend on how large or powerful the device is. Also, the strength of the magnetic field may vary a lot even among similar products.
For example, some hair dryers have a very strong field, while others produce hardly any EMF. It all depends on the product design. Also, exposure levels vary considerably depending on the distance you are from the device and how long you’re exposed.
Because of these variances, it’s difficult to say with accuracy what the EMF is for products. But both ICNERP and WHO internationally, and the EPA nationally, have stated that the EMF exposure in the average living environment is extremely low.
Possible human health effects from exposure to EMFs hasn’t yet been determined with precision and accuracy. Research in the coming years may better inform us.
Some studies point to various symptoms coming from EMF exposure, but researchers generally say more study is needed. Many of the studies use animal or cell models, which are unreliable if applied to human health.
Also, some of these symptoms have been attributed to a condition called electromagnetic hypersensitivity (EHS), where people relate various non-specific symptoms to EMF exposure.
The medical field hasn’t substantiated EHS, although people do experience symptoms that are sometimes distressing and even disabling.
No credible research currently links EHS symptoms to EMF exposure, and EHS isn’t considered to be a medical diagnosis. The medical field advises that further research is needed.
Still, some research gives tentative support to EMF symptomatology. Here are symptoms that some studies have suggested:
Low- to mid-frequency EMFs
Remember that this category of EMFs includes extremely low frequency EMFs (ELF-EMFs) and radiofrequency EMFs (RF-EMFs). This type of radiation is produced by any electric device. These devices range from refrigerators and vacuum cleaners to televisions and computer monitors (when they’re turned on). According to WHO, extremely low frequency and radiofrequency EMFs are unlikely to cause any adverse health effects. You should feel safe using your cell phone and appliances. Power lines are also considered safe, as long as you keep a safe distance from them. The EMF strength around appliances diminishes rapidly with distance. At 1 foot, the magnetic fields surrounding most household appliances are more than 100 times lower than the limit in the ICNERP guidelines for the general public. •Don’t sit or linger near appliances. One of the best ways to avoid EMF exposure in your home is to keep your distance from appliances. You need to get up close to turn on the television, open the fridge or microwave, and load the washing machine. Just keep these close encounters short, and don’t sit next to appliances — or allow your kids to. •Put your phone down. Especially when you aren’t using the phone, place it away from you. At night when you sleep, put it in another room. •Use the speaker function or earbuds with your phone. This will reduce RF exposure to your head. Earpieces do generate and emit fields, but not nearly as much as your phone. Using earpieces or speakerphone, you can greatly reduce exposure to your head. •Don’t carry your phone in a pocket. Try to carry your phone in a bag or briefcase when you’re out. •Unplug occasionally from electronic devices and electricity. Take a day off from electronics, or even several days. Your body will thank you!
High-frequency EMFs
Remember, this is the type of radiation that’s potentially dangerous to your health. High levels of high-frequency EMFs can damage DNA and cells. Low levels of this radiation come from medical devices like X-ray imaging machines , and UV rays from tanning beds or the sun. To reduce high-level exposure and associated risks, try these tips: •Limit X-rays. Only receive X-rays that are medically necessary. •Limit your time in the sun. You need some sun for your health, just not too much. Also, avoid sun during the middle of the day when the rays are strongest. •Limit time in tanning beds. If you must have that quick summer tan, just limit your time under the lights. If you want to calculate your effective dose of ionizing radiation per year, you can try using the EPA’s Dose Calculator. It carries a warning from the EPA that ionizing radiation is the type of EMF that’s dangerous because it can potentially harm body tissues and DNA.
EMFs occur naturally and also come from human-made sources. Scientists and regulatory agencies generally agree that low-frequency EMFs pose little danger to human health.
But some researchers offer preliminary evidence that some danger may exist for long-term use, specifically to the nervous system and brain cognitive function.
Exposure to large levels of high-frequency EMFs is known to damage human DNA and cells. But it’s very unlikely that you’ll be exposed to levels high enough to endanger your health in your daily life. Exposure comes mostly in small amounts.
The best approach is to be aware that EMFs exist and be smart about your exposure. This is a developing field of research that will undoubtedly expand as our use of wireless devices and labor-saving machines increases. Keep an eye on the news for developing research.
Ionization - The process of adding one or more electrons or removing one or more electrons. Very high temperatures, electrical discharges, or nuclear radiation can cause ionization. Radiation - Energy in the form of particles or waves moving through space or matter. Familiar radiations are heat, light, radio waves, and microwaves.
Jul 24, 2024 · Richard Hansler, a light researcher at John Carroll University in Cleveland, notes that ordinary incandescent lights also produce some blue light, although less than most fluorescent lightbulbs. Protect yourself from blue light at night. Use dim red lights for night lights. Red light is less likely to shift circadian rhythm and suppress melatonin.
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Apr 24, 2023 · The longer the wave, the less energy it transmits. Blue light has very short, high energy waves. In fact, they’re only slightly longer and less powerful than UV waves, which are too short for ...
Aug 4, 2016 · One can imagine electromagnetic waves as series of very regular waves that travel at an enormous speed, the speed of light. The frequency simply describes the number of oscillations or cycles per second, while the term wavelength describes the distance between one wave and the next.
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Nov 16, 2022 · There are three different types of ultraviolet radiation based on the size of the wavelength: UVA causes your skin to wrinkle, tan and/or burn. Too much exposure leads to skin cancer. UVB can damage the outermost layers of your skin. It can cause sun spots, tanning, sunburns and blistering, which can lead to skin cancer.
