EMF, in this case, is an acronym for "electromagnetic field". According to the U.S. Department of Energy, some studies have found higher incidence of cancer and other illnesses amongst people exposed to strong electromagnetic fields from high-power electrical lines and other sources, but results have generally been inconclusive.
Electromagnetic Radiation
Electromagnetic radiation is an ionizing radiation. In other words, it creates charged atoms or groups of atoms, known as ions, in the air. An abundance of positively charged ions can cause tiredness, depression and irritability, amongst other ailments.
Negative Ions
Proponents of "negative ion" air fresheners, such as rock or crystal lamps, claim that these devices flood the air with negative ions when heated. In so doing, they redress any imbalance between positive and negative ions.
Evidence
The U.S. Department of Energy agrees that there is some evidence that negative ions do "clean" the air and may provide health benefits. Indeed, there is further evidence that negative ions promote fast reaction times and positive mood.
Tags: negative ions, Department Energy, evidence that, evidence that negative, that negative
