Do LED Lights Contain Mercury?
LED lights do not contain even the slightest trace of mercury, which makes them the safest alternative for automotive lighting. Other forms of light bulbs, such as the HID bulbs, contain mercury as well as a number of other toxic chemicals that emit vapors into the environment, making them very dangerous. Some of the following light bulbs do contain mercury, and special care should be taken when handling them. [source: LEDlights.org]
High-intensity discharge (HID) contains mercury