While many people probably have them in their medicine cabinets, or on their walls, the retail sale of mercury thermometers has been banned or restricted in at least 18 states, including Washington, with more such legislation pending, according to the Interstate Mercury Education and Reduction Clearinghouse.

Mercury thermometers are also on their way out in a wide range of industries, along with a long list of other measuring devices, thermostats and switches that rely on mercury parts.

NIST and the Environmental Protection Agency (EPA) are taking other regulatory steps that would limit the use of those mercury-based products, and provide options.

And beginning Tuesday, the National Institute of Standards and Expertise (NIST), in Gaithersburg, Md., no longer will provide calibration services for manufacturers and users of mercury-in-glass thermometers a critical service it had provided to American industry since 1901.

“Due to elemental mercury’s high toxicity, EPA seeks to reduce potential mercury exposures to humans and the environment by reducing the general use of mercury-containing products, including mercury-containing thermometers,” EPA spokesman Dale Kemery said.

NIST officials expect the mercury thermometer will be officially obsolete within five years. And none? soon.

Exposure to high levels of metallic mercury vapors may cause permanent damage to the brain, kidneys and a developing fetus. Brain damage may finish up in irritability, behavioral changes, tremors, changes in vision, hearing and memory issues, according to the Centers for Disease Control and Prevention (CDC).

?