Environmental Health

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Where exactly do EMFs come from and how do they work?
The science behind electromagnetic fields is complicated, but the California EMF Program has put together a digestible guide that explains EMFs in common language.

For a more scientific and detailed explanation of the science behind EMFs, check out this thorough guide developed by the World Health Organization or this comprehensive guide developed by the California EMF Program.

If you want to learn more about the broader topics of radiation and the electromagnetic spectrum as a whole, check out this site by the National Safety Council.

Why the controversy?
The controversy over the health effects of EMFs seems to exist because most of the studies have been inconclusive. Most reputable studies that show a link between EMFs and negative health effects only show weak links. Other studies show no links at all. Yet, others seem to be biased in who was chosen for test subjects, or biased in making assumptions about subjects’ actual amount of exposure to EMFs. Regardless of how earnest each study is, it’s difficult to study what seems to be predominately a long-term health issue, especially when the cause is something as pervasive to our lives as EMFs. In that scenario, it’s difficult to isolate the effects of EMFs from other variables.

Also, powerful groups on both sides of the issue can spread misinformation about EMFs. There is a lot at stake in the fight over EMFs because a number of businesses depend on the manufacture of electric items and the distribution of electricity. On the other side, a number of individuals and groups are eager for lawsuits claiming harmful EMF effects so they can sue businesses with deep pockets.

Many reputable health authority organizations, such as NIEHS agree on one thing: that more conclusive studies could be done, and in the meantime, the public should exercise “prudent avoidance” which means that we should take precautions to avoid unnecessary exposure, but that we shouldn’t waste a considerable amount of time or resources that may be better spent on more obvious environmental health issues.

What exactly are the most conclusive known health effects?
Before you learn about the health effects, it’s important to understand what is meant by the common term “EMF’ in the context of studies on health effects. Most EMF studies are based on frequencies and energy levels within the range of normal exposure for most of the population, which for the most part includes sources of non-ionizing radiation. In other words, they are studies based on how EMF fields can affect humans from things people normally encounter, such as wiring, electrical appliances, and lighting in their homes and workplaces, and then from power lines or transformers outside.

What is non-ionizing radiation? According to ThinkQuest, non-ionizing radiation is radiation that carries less than 1216 kJ/mol of energy and according to the World Health Organization, does not have enough energy to break chemical bonds. Instead, it has the potential to move atoms around in a molecule or cause atoms to vibrate. Examples are radiowaves, microwaves, infrared, and visible light. Ionizing radiation, on the other hand carries more than 1216 kJ/mol of energy and does have enough energy to break chemical bonds in molecules according to the WHO. Examples are x-rays, gamma rays, and cosmic rays-- all items that are not usually associated with the term “EMF.” Breaking chemical bonds in molecules can certainly be detrimental to human health.

Therefore, there is a distinction between what is frequently meant by EMFs versus other forms of electromagnetic forces. Within the scientific community, it’s not a question that most forms of ionizing radiation pose a health risk, such as cancer. This is why precautions are taken to minimize x-ray exposure when you get an x-ray in a doctor’s office and why everyone agrees that nuclear explosions are dangerous. For the health risks associated with ionizing radiation, visit OSHA’s informational page on the issue.

The controversy that pursues over EMFs is based mostly, but not always, on the potential health effects of non-ionizing sources of radiation, and how forces that can’t break chemical bonds negatively affect the life processes of humans. Furthermore, the term “EMF” is not only referring to non-ionizing sources of radiation, but it is often referring to sources that are also extremely low-frequency, because higher frequency sources, even of non-ionizing radiation can certainly be dangerous. To see this concept visually, click here, and look at where “extremely low-frequency” is on the graph. Higher frequency non-ionizing sources of radiation can move atoms around in a molecule or cause atoms to vibrate according to the EPA, making them dangerous through sources such as lasers, which can burn or microwaves, which can heat. In conclusion, the general term “EMF” usually means non-ionizing sources of radiation that are extremely low-frequency. So, behind the controversy is this scientific question that has yet to be answered: if a source of radiation is non-ionizing and extremely low-frequency, how exactly could it negatively affect life processes?

Now for the health effects of what is commonly meant when people say “EMFs”… According to Medline Plus, some studies have shown a weak link between EMFs and childhood leukemia whereas other studies couldn’t find a link between EMFs and other childhood cancers. The most reputable report to come out so far claiming possible negative health effects was the report issued by the National Institute of Environmental Health Sciences. A task group, led by Director Kenneth Olden, spent 18 months reviewing scientific literature about EMFs’ potential health effects. The 1998 report concluded that 60-Hertz EMFs, such as those surrounding power lines, could be regarded as a possible human carcinogen (meaning that they could have the potential to cause cancer).

According to Medline Plus, however, most studies based solely on adults show even less proof of serious health effects, and at the most, there could be a link between EMFs and heart rate interference, or interference with the electrical brain activity during sleep. Both these issues may not cause actual problems.

Many prominent health organizations have tried to make sense of the array of conflicting studies. Panels for these organizations have comprehensively studied the available scientific literature and come to their own consensuses. For a list of these organizations and access to their reports, click here.

Are you still confused about EMFs or radiation in general?
If you are a visual learner, this source will be great for you! Check out the interactive map of radiation by the EPA called RadTown USA. It is a cartoon map of a town where you can click anywhere and find information about radiation sources in and around the object you clicked on.

Bring radiation into the classroom!
We’re talking about just radiation education, of course! If you’re interested in teaching your students about radiation, including EMFs, check out this activity book on radiation from the National Safety Council.