Electromagnetic fields are present on a basic level across the universe, in varying degrees of strength. The Earth, for example, is surrounded by an electromagnetic field generated by the movement of electrons inside the Earth, and this field is taken advantage of when people use compasses to orient themselves. The behavior of such fields is determined by the wavelengths of energy generated, and the frequency of their oscillations. Long wavelengths oscillate at a low frequency, while short wavelengths oscillate at a high frequency.
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Many people have noted that they can feel a hum of energy around power lines, and studies have shown that the electromagnetic field which surrounds high energy power lines can actually impact the growth of plants inside the field, illustrating the way in which an electromagnetic field can act on charged particles inside the field. Certain types of electromagnetic fields have been linked with health concerns. Several studies on cancer have shown that some childhood cancers have been linked with exposure to high energy electromagnetic fields. Even as an electromagnetic field causes health problems, however, it can also be beneficial. For example, in the medical community, people use x-rays, a form of electromagnetic radiation, to see the inside of the body, and lasers, another form of electromagnetic radiation, to perform surgery.
If you are concerned about electromagnetic pollution there are ways to protect yourself. The primary example would be to limit exposure, such as not using microwaves, texting on mobiles rather than calling, limiting x-rays, avoiding sunbeds etc. Other ways to protect yourself are to buy various tools such as crystals, grounding sheets, protectors for computers and mobiles, amongst others things. If you are very sensitive and suffer from insomnia, chronic fatigue, allergies etc. you may want to try some of these ways to minimise your exposure.