If broken in a sink a glass thermometer filled with mercury can pollute up to five million gallons of water, and if tossed into trash a mercury thermometer can break and potentially leak mercury in a landfill, which could then filter into groundwater.
"We want to get these old thermometers out of medicine cabinets and eliminate this potential source of pollution," said Melody Tovar, deputy director of watershed protection for the city's environmental services department in a statement. "Everything that flows down the drain or into the city's storm sewer system can pollute the waters of our local creeks or the south San Francisco Bay."
More than 1,300 mercury thermometers have been collected by the environmental services department since it began the exchange program last year. The mercury-filled thermometers are recycled thereby reducing the demand for new mercury.
Mercury bioaccumulates in fish muscle tissue, which means it can travel up the food chain through other fish and ultimately to people who consume those fish. It is a neurotoxin that can have negative health affects on the nervous system, brain, kidneys, liver and immune system in humans and animals.
The exchange service will take place Saturday from 10 a.m. to 2 p.m. at the Edenvale Branch Library at 101 Branham Lane East in San Jose. One free digital thermometer is available per household.