We now know that mercury is a potent neurotoxin, too harmful to keep around the house. When mercury thermometers get broken or are tossed in the garbage, toxic mercury is released. So you may want to swap out your old mercury thermometer for a non-mercury model at one of the many drugstores that now offers a thermometer exchange program. (Nine of the ten largest drug chains currently do so — for details, see noharm.org.) Or take your old thermometer to a local mercury-recycling site. Safer options include an inexpensive alcohol glass thermometer from your local drugstore or a digital oral thermometer — Vicks makes a good one for about twelve bucks. And with squirmy youngsters, an electronic ear thermometer like the Braun Thermoscan can be a godsend.
— Tom Ferguson
Vicks Digital Thermometer
Braun Thermoscan Ear Thermometer