RF Emissions and Health:

Government regulatory bodies have set exposure standards for personal wireless devices such as mobile phones and Bluetooth enabled devices. These limits are expressed in terms of the "specific absorption rate" (SAR), which is a measure of the radiation that actually reaches your body tissue. The maximum level adopted by the U.S. and Canadian governments is 1.6 watts per kilogram, while the level set by the European Union is slightly higher.

Bluetooth enabled wireless devices operate at much lower power levels than phones, so the radiation created by a Bluetooth enabled headset is insignificant by comparison. A study by William G. Scanlon of Queen's University in Belfast found that a typical Bluetooth radio module generates an SAR of just 0.001 watts per kilogram, or less than 1/1000 of the maximum safe radiation level set by the government authorities.