Does an instant thermometer used for cooking contain mercury?

Modern instant-read thermometers typically do not contain mercury. Most use a thermocouple or thermistor to sense temperature, which converts the temperature into an electrical signal that is displayed on a digital readout. Older thermometers may contain mercury, but these are becoming less common due to safety concerns associated with mercury spills. If you have an older instant-read thermometer, it's a good idea to check the manufacturer's instructions for proper disposal.