Mercury occurs naturally in the environment and exists in several forms. These forms can be organized under three headings: metallic mercury (also known as elemental mercury), inorganic mercury and organic mercury. Metallic mercury is the kind found in thermometers and some light bulbs. It is a silver-colored liquid at room temperature. It easily evaporates. Breathing large amounts of mercury vapors can cause harm. Touching or even swallowing metallic mercury is not very harmful. Although uncommon, inorganic mercury is toxic to the human body. In large amounts, organic mercury found in fish and wildlife can potentially be harmful.
Old thermometers may contain mercury. If broken open, the spilled liquid mercury can be messy. A small mercury spill, such as a broken thermometer, is a nuisance but not an emergency. The amount of mercury in a thermometer is so small that it is not believed to be a health hazard. For small spills such as cleaning up broken mercury thermometers:
If a broken thermometer is cleaned up properly and promptly, your family will be safe.
Mercury was used for many years in thermometers designed for household use because no alternatives were available. However, this is no longer the case. In July 2001, the American Academy of Pediatrics issued a policy statement about the health effects of mercury. They also urged doctors and parents to stop using mercury thermometers and to dispose of them properly. Today, better alternatives such as digital or mercury-free thermometers are readily available.
Mercury thermometers, as well as other types of mercury-containing items such as old thermostats, barometers, meat thermometers, candy thermometers, manometers, blood pressure cuffs, and other household mercury waste or devices, can be brought to a Household Hazardous Waste Collection where they will be accepted for proper disposal. Municipalities such as Davidson, Hamilton, Knox and Shelby counties have permanent sites. Other counties may have special collection days. For more information about how to properly dispose of household hazardous waste in Tennessee, please visit or call 615-532-9265.