Virginia Beach, a small beach community in southeastern Virginia, is known for many things: a beautiful pier, the Cape Henry Lighthouse, and First Landing State Park.
But it has made headlines recently for another reason: opposition to an offshore renewable energy project.
On June 20, members of the Sandbridge Beach Civic League, a community group of the seaside community, voted unanimously against Avangrid Renewables’s proposed Kitty Hawk Offshore Wind Project.
The proposed project would build an offshore wind farm about 26 miles off the coast of North Carolina and transport the renewable electricity back to the mainland through underwater cables.
So, why the opposition?
The group’s members cite potential health hazards from exposure to electromagnetic fields generated by the transmission cables that would run through the community, the Virginian-Pilot has reported.
So are these residents justified in worrying about exposure to the electromagnetic fields caused by electricity transmission cables? Do electromagnetic fields cause harm to human health?
Yes and no. Here’s what you need to know.
1. What Are Electromagnetic Fields?
Electromagnetic fields (EMFs) are areas—fields—of energy in which the energy has both electrical and magnetic components. These fields are created when electrical charges accelerate.
The waves of electromagnetic energy that make up the electromagnetic field are called electromagnetic radiation. They include radio waves, microwaves, X-rays, gamma rays, infrared light, and even visible light.
The strength of EMFs depends on how much electricity is in use (the current), the amount of electrical potential (the voltage), and the strength of the magnetic field. Electrical fields are measured in volts per meter (V/m) while magnetic fields are measured in Teslas (T).
Another characteristic of EMFs is the frequency of the source of electricity. Frequency is how quickly the flow of electricity changes over time. It’s measured in hertz (Hz), which is the number of cycles of electricity per second. In North America, the frequency of the electrical system is 60 Hz. In Europe, it’s 50 Hz.
Man-made EMFs are created anywhere there is electricity, including your household appliances.
They’re also created naturally by the earth.
The earth’s magnetic field, called the magnetosphere, is generated by the molten iron core of the earth. This field is responsible for a number of effects from the northern lights to compasses pointing north. It’s even responsible for protecting us from cosmic radiation.
Even our own bodies produce these fields, though they are very weak. Your nervous system—your brain spinal cord, and all your nerves—functions by transmitting electrical impulses. Even your heart generates electrical activity.
These examples give us the first answer to our question: no, not all electromagnetic fields are harmful. Certainly, the earth’s magnetic field isn’t. And neither is the visible light created by a flashlight.
Ionizing Versus Non-ionizing Electromagnetic Fields
But yes, some electromagnetic fields can be harmful.
EMFs can be grouped into two categories based on their frequency. The energy that makes up EMFs are waves, and frequency is the number of full oscillations of those waves that occur in a second.
Low-frequency electromagnetic fields are called “non-ionizing.” These low-energy fields include, for example, the electromagnetic energy waves that are created by lightning as well as others that exist naturally, like Schuman resonances. Low frequency, non-ionizing fields of electromagnetic energy are usually harmless.
High-frequency fields are called “ionizing.” These high-energy fields include things like gamma rays, x-rays, and even ultraviolet light from the sun. Under some circumstances of prolonged exposure to UVA, these can lead to cellular damage and even damage DNA.
The Biological Effects of Electromagnetic Fields and Radiation
Since the 20th century, people have been increasingly exposed to man-made electromagnetic fields. We’re exposed to weak EMFs at home, at work, at school, and where we socialize. Sources of EMFs include our home appliances, industrial equipment, and our electronic devices.
EMFs can cause biological effects on the human body. They do this by influencing the distribution of electrical charges within human cells.
A biological effect simply means a response by your body to a stimulus that’s big enough that you can measure it. How much of an effect an EMF has on the body depends on the strength of the currents that the EMFs create within the body. For example, if they are strong enough, fields of electromagnetic energy can stimulate nerves or muscle fibers.
The most common biological effect of EMFs is heating—which is precisely how microwave ovens heat up food.
According to the World Health Organization (WHO), the level of EMF energy people are normally exposed to is very low—much lower than that needed to produce significant heating.
2. Can EMFs Be Harmful?
Just because something has a biological effect doesn’t necessarily mean that it is harmful. For example, running produces a range of biological effects on your body that we wouldn’t consider harmful. Meditation appears to have biological effects, too.
Similarly, visible light—a form of electromagnetic radiation—has biological effects on the body, including the dilation of pupils in the eye. This biological effect is not necessarily harmful.
So when are the biological effects of an EMG considered to be a health hazard?
EMFs are harmful when they cause a detectable impairment in health to the exposed individual.
And they certainly do cause a detectable impairment in health when they are intense enough. For example, gamma rays can cause irreversible damage to tissue and DNA.
So there is widespread agreement that EMFs certainly can be harmful to people. According to the WHO, “There is no doubt that short-term exposure to very high levels of electromagnetic fields can be harmful to health.”
EMFs Can Be Both Harmful and Benign—Depending on Strength and Exposure
In the conversation around the harm of EMFs, there is a consensus around two facts:
- High-frequency electromagnetic fields—the ionizing ones—can cause harm to human health. These include things like UV light and gamma rays.
- It’s also widely accepted that even low-intensity EMFs—non-ionizing ones—can have biological effects on humans that aren’t harmful. Visible light falls in this category.
But there still remains some disagreement about the potential harm EMFs can cause humans. The current debate centers around low-intensity, non-ionizing EMFs.
Can regular, low-level exposure to non-ionizing EMFs—such as those from power lines—cause harm?
The Health Effects of EMFs Are Well Researched
The health effects of EMFs have been vigorously studied. Over 25,000 studies have been published about the health effects of non-ionizing radiation in the past 30 years.
Even with this massive body of literature, the evidence does not yet point to a clear link between low-intensity EMF exposure and health issues.
Here are some of the most common health concerns linked to exposure to low-intensity EMFs and what the current evidence says.
Cataracts. Some workers who are regularly exposed to microwave radiation have complained of eye irritation and cataracts. This has prompted inquiry into the effects of low-frequency EMFs and eye health.
Experimental research has not produced supporting evidence for this. Only radio frequencies that are high enough to significantly raise the temperature of eye tissues have been found to be an issue. These are not common among exposure to the public.
Skin cancer. Previously people thought prolonged exposure to ultraviolet (UV) radiation, which is present in sunlight, can cause skin damage and even skin cancer.
However the truth is not as simple as that.
In 2003 Janet Maldonado, MD, and colleagues found that BRAF mutations were statistically significantly more common in melanomas occurring on intermittently sun-exposed skin than elsewhere. By contrast, BRAF mutations in melanomas on chronically sun-damaged skin were rare.
In 2009, Nick Levell et al had analyzed the histological diagnosis, mortality, and incidence of all lesions reported as melanomas in East Anglia between 1991 and 2004; and concluded that the large increase in reported incidence of melanomas was likely to be due to diagnostic drift. The distribution of the lesions reported did not correspond to the sites of lesions caused by solar exposure.
People have explained the surprising outcomes of these studies by using the fact that ultraviolet light has different components, the vitamin-D-producing UVB rays and the skin-damaging UVA light. Both UVA and UVB can cause tanning and burning, although UVB does so far more rapidly. UVA, however, penetrates your skin more deeply than UVB, and may be a much more important factor in photoaging, wrinkles, and skin cancers.
To put it simply, UVB appears to be protective against melanoma—or rather, the vitamin D your body produces in response to UVB radiation is protective. It has been reported that outdoor workers had a decreased risk of melanoma compared with indoor workers, suggesting that chronic sunlight exposure can have a protective effect.
Our bodies can convert the vitamin D in our bloodstream into calcitriol, which is the activated form of vitamin D. Our organs can use it to repair damage, including damage from cancer cells and tumors. Vitamin D’s protective effect against cancer includes multiple ways:
- Promoting the self-destruction of cancer cells with gene mutations
- Counteracting the spreading and reproduction of cancer cells
- Helping cancer cells turn to differentiated, normalized non-cancer cells
According to epidemiologist Cedric Garland, DrPH, professor of family and preventive medicine at the UC San Diego School of Medicine, there are more than 200 epidemiological studies, and more than 2,500 laboratory studies about vitamin D’s protective roles in various types of cancers.
Childhood Leukemia. Much research on EMFs causing cancer has been conducted, and it is somewhat mixed. On the one hand, several epidemiological studies have suggested that exposure to low-intensity EMFs may slightly increase the risk of childhood leukemia. The results of these studies prompted the International Agency for Research on Cancer to classify low-frequency magnetic fields as a “possible carcinogen.”
But experimental studies haven’t supported the findings of those epidemiological studies. And, there isn’t yet a clear biological explanation for how cancer could be caused by the low-frequency electromagnetic fields. Some researchers have also suggested that the epidemiological studies may have suffered from methodological issues.
For example, one Danish study found that proximity to power lines or electrical substations significantly (being within 150 m of a 220–400 kV line or substation) increased the risk of developing leukemia, CNS tumors, and malignant lymphoma for children diagnosed from 1968 to 1986. But the same researchers didn’t find an increased risk for children diagnosed between 1986 to 2003.
The researchers suggest that rather than proximity to powerlines, there may be some other explanation, including that, “the decrease in risk over time might be due to a change in characteristics of the population living close to power lines” or even changes to the house buildings over time.
Larger, more rigorous studies may help clarify the connection between cancer and proximity to strong EMFs. If there is an effect of EMF on the risk of cancer, it appears to be so small that it is often undetectable.
Electromagnetic hypersensitivity. Some individuals have reported being sensitive to electromagnetic energy. They report symptoms ranging from pains, headaches, lethargy, to depression, and sleep disorders.
The research evidence for this kind of sensitivity is shaky. Some studies note that individuals do not report symptoms consistently when exposed to EMFs in controlled conditions. While these responses may be due to exposure to EMFs, they may also be due to other factors.
Pregnancy. According to the WHO, the impact of EMF on pregnancy seems to be minor. However, as pregnant women are normally frequent users of house electronic devices (e.g. vacuum cleaner, hair dryer), it may be safest if pregnant women wear an anti-EMF radiation shield dress during pregnancy.
Possible Beneficial Effects From Exposure to EMFs
Overall, on the basis of that research, the WHO concludes, “To date, there is no evidence to conclude that exposure to low-level electromagnetic fields is harmful to human health.”
While the jury is still out on whether low-intensity EMFs could be harmful in some circumstances, scientists are also looking to see whether they may also be beneficial.
For example, Schumann resonances are natural pulses of electromagnetic energy that emanate from the earth through our atmosphere. Some research has suggested that these pulses contribute to our health and could even be used as a treatment for cardiovascular diseases.
In repeated experiments, Nobel Prize laureate Professor Luc Montagnier amazingly demonstrated that a low intensity electromagnetic field (EMF) of 7 HZ (similar to Schumann resonances), could produce DNA in a tube of pure water, simply by being adjacent to another tube containing DNA. In other words, he created something—DNA—out of nothing, simply by being close to DNA and adding low frequency EMFs.
This suggests the potential beneficial regenerative effects of low-intensity EMFs like Schumann resonances.
Even gamma rays, which can be harmful to humans, are occasionally used as a medical treatment for cancer. They are used to damage the DNA of tumor cells so that the cancerous tissue dies. This is called Gamma Knife radiosurgery. Of course, because gamma rays can also damage healthy tissue, doctors must be very careful when delivering this treatment.
3. Potential Harm and Government Guidelines
Because EMFs are potentially harmful, various governmental bodies regulate them. While governments set their own regulations, many use the standards set by the International Non-Ionizing Radiation Committee (INIRC). This committee is made up of scientists who look at the existing research and make recommendations on the level of non-ionizing electromagnetic radiation that is likely to be harmful to individuals.
For 50 Hz electrical and magnetic fields, the current guidelines are that the general public should not be exposed on a continuous basis to electric field strengths exceeding 5 kilovolts per meter (kV/m), or to magnetic fields exceeding 200 microteslas (µT).
For people that work with electricity, like electrical engineers or service personnel, the recommendations are to not be exposed to electric fields greater than 10 kV/m or magnetic fields greater than 1,000 µT.
What Do These Guidelines Mean?
They mean that exposure to levels below these guidelines is safe, at least according to current scientific knowledge. Exposure to levels above those levels may pose greater risks, although they are still not necessarily dangerous. As exposure increases, and as the strength of the fields increases, the risk of harmful effects also increases.
How much exposure do we get to EMFs at home?
The electrical appliances that we have in our homes can produce surprisingly strong electromagnetic energy fields. For instance, here are the typical magnetic field strengths for appliances at three distances as reported by the WHO.
Typical strengths of magnetic fields for household appliances (normal operating distance bolded)
|Appliance||µT at 3 cm distance||µT at 30 cm distance||µT at 1 m distance|
|Refrigerator||0.5 – 1.7||0.01 – 0.25||Less than 0.01|
|Computer||0.3 – 30||Less than 0.01|
|Washing machine||0.8 – 50||0.15 – 3||0.01 – 0.15|
|Microwave oven||73 – 200||4 – 8||0.25 – 0.6|
|Vacuum cleaner||200 – 800||2 – 20||0.13 – 2|
|Electric shaver||15 – 1500||0.08 – 9||0.01 – 0.03|
|Hair dryer||6 – 2000||0.01 – 7||0.01 – 0.03|
You might be surprised at how strong the magnetic fields can be from typical appliances. The strength of an electromagnetic field isn’t necessarily related to the size or power of the appliance, either. For example, the modest hair dryer has a significantly stronger field than the much larger refrigerator.
Another important thing to note, demonstrated by the chart above, is that the fields decrease in strength very quickly over short distances. The power of the fields of most of these appliances is negligible at a meter distance.
Finally, note that the range in strength of magnetic fields depends on the design of the product. Some hair dryer products, for example, may have significantly higher magnetic fields than others.
Still, most of the appliances we have in our homes are below INIRC’s general public guideline limit of 200 µT, especially when used at their typical operating distance.
Overall, the evidence suggests that typical daily exposure is well below guideline levels. One study by the Federal Office for Radiation Safety in Germany followed 2,000 individuals with a range of occupations throughout their lives—at school, work, and at home. While exposure varied widely across the individuals, the average exposure was 0.10 µT. That’s 2,000 times lower than the exposure limit of 200 µT for the public.
4. What About Transmission Lines?
According to the WHO, the background level of electric fields in the home is about 0.1 kV/m and the background magnetic field is about 0.2 µT. These fields are generated by the electric wiring and appliances present in most homes. Both these levels are well below INIRC’s guidelines.
Around power lines, those fields get much stronger. Directly beneath power lines, the electrical field goes up to 10 kV/m and 20 µT. This is still below the guideline for magnetic fields, but above the guideline for electrical fields.
Note that the research finds that the field diminishes significantly over short distances, reaching normal levels (less than 0.1 µT) after about 150 meters.
That could be why even people that live fairly close to power lines may not get substantially more exposure to EMFs than other people. In the earlier study by the German Federal Office for Radiation Safety, people that lived in close proximity to power lines had exposure levels that didn’t differ significantly from the average person’s exposure.
5. Most EMFs Won’t Cause You Harm, but Minimize Exposure if Possible
So are Sandbridge residents justified in being worried about hazards to health from the electromagnetic fields produced by electricity transmission lines?
Perhaps. It’s true that the electric and magnetic fields within 150 meters of the transmission line would likely produce EMFs with strengths above the ICNIRP guidelines.
While the link to adverse health effects (like cancer) is still slightly unclear, it does appear that under some circumstances, exposure to even low-intensity EMFs are associated with health hazards, including cancer in children.
So the concern for health may be warranted.
More generally, we’re constantly exposed to electromagnetic fields in our homes, at work, and in our communities. Usually, the strength of the fields is too weak to produce negative effects on our health. But it won’t hurt to avoid them when you can.
Furthermore, there are still many unknowns to be fully elucidated, including the complete picture of interactions of environment, invisible waves, energy fields, and another marvelous world—our human body. We will finally be there one day.
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