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?
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?
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.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.
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.
Ionizing Versus Non-ionizing Electromagnetic Fields
But yes, some electromagnetic fields can be harmful.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.
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.
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.
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.
However the truth is not as simple as that.
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.
- 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
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.
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.
This suggests the potential beneficial regenerative effects of low-intensity EMFs like Schumann resonances.
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.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.| 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.
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.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.
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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