Artificial electromagnetic waves are the most common and rapidly growing source of exposure in the modern world, including exposure to several frequency groups: extremely low frequencies from power lines, hybrid car batteries, and high-voltage lines (>3 Hz-3 kHz); radio frequencies; microwave frequencies, including millimeter waves (3 kHz-300 GHz) from cell phones, towers, base stations, and wireless devices; and intermediate frequencies, so-called "dirty electricity" produced by power cables.