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Broken Thermometer

Donít Mess With Mercury           


Why is mercury a problem?


Mercury seeps into lakes and waterways, it undergoes a natural chemical process and is converted to a more deadly form - methyl mercury. Local water ways are susceptible to contamination by mercury-an element used in many household items, which is also a potent human nerve toxin. When disposed of improperly, it contaminates the food chain by building up in the tissue of fish and animals including those we eat. Because of toxic chemicals sometimes found in fish, the Office of Environmental Health Hazard Assessment issues a Fish Consumption Advisory for fish consumed out of the San Francisco Bay and Delta. Humans are at risk when they consume fish and wildlife from areas impacted by mercury or when they breathe vapors from liquid mercury.


What is elemental mercury?


Elemental, or metallic, mercury is the shiny, silver-gray metal found in thermometers, barometers, thermostats and other electrical switches.  Mercury can break into droplets when spilled, spread easily, and can build up in tiny cracks and spaces wherever it is spilled.


 Ways you can help!

Mercury in Homes

Properly Identify and Dispose of Mercury Containing Items
Visit the EPA's Site for Consumers
California Integrated Waste Management
Mercury in the Environment
Consuming Delta Watershed and Commercial Caught Fish
Visit the EPA's SIte for Fish Consumption Advisories
Total Maximum Daily Load Program
Mercury in Business Small Quantity Generator
Visit the EPA's Site for Business and Industry
California Department of Toxic Control Substances: Mercury Waste

Important Mercury Facts
  • Mercury is also known as quicksilver because of its silvery color and reflective metallic nature.
  • Elemental mercury is a liquid at room temperature.
  • It is the "invisible" vapors of mercury that are the true hazard.
  • Just playing with mercury one time can contaminate the body, clothes, and property to the point they cannot be decontaminated. 
  • One drop of mercury can impair an entire lake.
  • High levels of mercury poisoning in children can affect their health forever.
  • A teaspoon of mercury if not cleaned up properly can contaminate a house so that it is no longer inhabitable.
  • Vacuuming or sweeping a mercury spill can create approximately 10 times more hazardous mercury vapors than cleaning it properly.
  • Once mercury hits the ground it breaks up into microscopic beads that you may not even see.

For more information, visit


PO Box 1810 / 1810 East Hazelton Avenue, Stockton, California 95201    |    Phone  (209)  468 - 3055

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The Stormwater Pollution Prevention Program is a Program of the

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Public Works Department

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