evidence: Early studies involving laboratory animals showed no evidence that radiofrequency radiation increased cancer risk or enhanced the cancer-causing effects of known chemical carcinogens (35–38). [...] The Federal Communications Commission (FCC) concludes that currently no scientific evidence establishes a definite link between wireless device use and cancer or other illnesses. [...] Use of wired or wireless headsets reduces the amount of radiofrequency radiation exposure to the head because the phone is not placed against the head (53). Exposures decline dramatically when cell phones are used hands-free. For example, wireless (Bluetooth) devices (such as headphones and earbuds) use short-range signals that typically transmit radiofrequency waves at power levels 10–400 times lower than cell phones (54).