How to Recycle a Mercury Thermometer

By Tammie Painter
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That old mercury thermometer in your medicine cabinet is toxic. Older thermometers contain up to 2 grams of mercury, a substance known to cause neurological, developmental and reproductive problems in humans and wildlife. Tossing these thermometers in the trash can lead to soil and water contamination. Instead of throwing them out, recycle your old thermometers so the mercury can be safely reclaimed and the glass reused.

Identify Your Thermometer

Before disposing of it, you need to determine whether your old thermometer contains mercury. Look at the thermometer. The majority of mercury-containing thermometers are made of glass. Next, examine the bulb of the thermometer. If it's silver, your thermometer contains mercury. Mercury-free thermometers will have a red, green or blue bulb.

Find a Handler

Because mercury is considered a hazardous substance, mercury thermometers should be taken to a hazardous waste facility for disposal. Some states have made this a requirement. Your garbage company or local environmental group can provide you with the hazardous waste handler nearest to your home or you can find a handler online.

Some areas periodically hold hazardous waste drop-off events where you can take items such as mercury thermometers, fluorescent bulbs, batteries and household chemicals.

Your city may even offer an exchange program for mercury-containing items such as thermometers and thermostats. At these exchanges, you can turn in your old thermometer and receive a coupon or credit toward a new mercury-free thermometer.

Packing & Storing

Before taking in your thermometers to a waste facility or exchange program, you'll need to pack and store them properly to prevent breakage.

Place the thermometers in a container with a secure lid and fill the container with cat litter or sand. This will absorb any mercury if the thermometers break. Then place the covered container inside another box such as a shoe box. Write a label that says. "This box contains mercury thermometers -- handle carefully and do not open." Securely place the label on the box with tape.

Until you can take the thermometers in, store the box in a place where it won't get knocked over.

Broken Thermometers

If you have an old thermometer and it breaks, you'll need to act quickly to prevent exposure to the vapors. First, clear everyone including pets from the room. Open the windows and close any doors in the room before you collect your clean up equipment.

Put on rubber or latex gloves and then pick up as many of the larger glass pieces from the thermometer as you can. Place these on a paper towel and carefully wrap up the paper towel. Put the paper towel in a zip-seal bag and close it.

With a piece of cardboard, gently collect as much mercury as possible and then pick up the rest of the mercury and glass shards with the sticky side of a piece duct tape. Seal the mercury, used cardboard and duct tape in a plastic bag.

With a damp cloth or paper towel, wipe down the area. Seal this rag and any other item used in the clean up, including your gloves, into a plastic bag. Place all the bags inside another sealable plastic bag. Label it "mercury waste" and store it as you would other mercury waste.