Mercury Contamination: Where is this stuff coming from?

Mercury is a long lasting, bioaccumulative toxin. That means that the toxin builds up in the food chain because organisms are absorbing a toxic substance at a rate greater than which the substance is being lost. Exposure at any level can have irreparable damage on the brain, heart, kidneys, liver and immune system of people of all ages. Mercury can be found in some of the fish we eat, but it can also be found in a variety of electronics and household hazardous wastes such as car switches, fluorescent lights, thermostats, and thermometers, Such mercury can be released through contamination or seepage from landfills if the items are not properly disposed of.

What We Know

Mercury is a global issue because it can be transported thousands of miles in the atmosphere before deposition. EPA's Mercury Study Report to Congress estimates that 3 percent of the total global mercury burden in the environment originates from U.S. sources. Between 50 and 75 percent of this 3 percent is caused by human activity, with the remaining amount originating from natural sources.

Where is the Mercury?

Mercury is also found in thermometers and thermostats. Both items are banned from landfills. Thermostats can contain over 3,000 milligrams of mercury.

What Has Been Done to Help Prevent Mercury Pollution

In 2001, California passed the California Mercury Reduction Act of 2001 (SB 633 - Sher). The Act required the removal and reduction of mercury in vehicle switches and thermostats. Specifically, the Act required the removal of mercury-containing switches in vehicles. The law also prohibited the sale or supply of mercury fever thermometers after July 2002. Mercury thermostats were banned from sale in California in January 2006.

AB 2347 (Assembly Member Ruskin), was signed by Governor Schwarzenegger in 2008, which created the Mercury Thermostats Collection Act. This Act requires manufacturers that sold mercury-added thermostats in this state before January 1, 2006, to establish and  maintain a collections and recycling program for out-of-service mercury-added thermostats.

In 2009, AB 1173 (Assembly Member Huffman), which successfully passed through the Legislature but vetoed by the Governor, would have set up a convenient mercury-containing light recycling program in California. In 2010 legislation, AB 2176 by Assembly Member Blumenfield is a different approach to providing recycling opportunities for mercury-containing lights.

Calculate Your Own Mercury Level

The Natural Resource Defense Council has a great system for obtaining a quick estimate of the amount of mercury currently in your blood with their Mercury Calculator. For a more accurate reading, you can request a blood mercury test from your physician. Women with a high blood mercury level who are planning to start a family may decide to postpone pregnancy for a few months until levels drop. Often this occurs over a three to six month time frame. Also available is another mercury calculator available at, a site that is part of the Turtle Island Restoration Network that also offers facts for fish eaters and how to take action to reduce the public's exposure to mercury in seafood.

What You Can Do

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