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Mercury and Mercury Compounds

Why am I being warned about potential exposure to mercury and mercury compounds?

  • Mercury and mercury compounds are on the Proposition 65 list because they can cause birth defects or other reproductive harm. Exposure to mercury and mercury compounds during pregnancy can affect brain development and cause learning and behavior problems for the child.
  • Methylmercury compounds are also on the Proposition 65 list because they can cause cancer. Exposure to methylmercury compounds may increase cancer risk and exposure during pregnancy can affect brain development and cause learning and behavior problems for the child.
  • Proposition 65 requires businesses to determine if they must provide a warning about exposures to listed chemicals.

What is Mercury?

  • Mercury is a heavy, silver-colored, liquid metal. It is found in:
    • Certain types of fish and seafood (in the form of methylmercury).
    • Silver-colored dental amalgam fillings.
    • Fluorescent lights, including compact fluorescent light (CFL) bulbs.
    • Glass thermometers, older barometers, other gauges, and some batteries.
    • Some skin creams used for skin-lightening, anti-aging, and acne treatment.
    • Some dietary supplements and traditional medicine. 

How does exposure to mercury and mercury compounds occur?

  • During pregnancy mercury can pass from the mother to the baby.

How can I reduce my exposure to mercury and mercury compounds, including methylmercury compounds?

  • Choose fish that are lower in mercury, such as salmon, tilapia, trout, canned light tuna, sardines, anchovies, and oysters.
  • Do not eat fish or seafood that is high in mercury, such as tilefish, shark, swordfish, king mackerel, marlin, orange roughy, bluefin tuna, and bigeye tuna.
  • When consuming fish that you, friends, or family catch, follow OEHHA sports-fish advisories and safe eating guidelines.
  • Follow the US Environmental Protection Agency’s instructions for recycling batteries, disposing of CFL bulbs and mercury thermometers, and cleaning up  broken CFL bulbs and mercury thermometers.
  • If you need a tooth filling, talk to your dentist about other restorative materials, such as resin composite, porcelain, and gold alloys.
  • Do not take Ayurvedic medicines that contain high levels of mercury.
  • Be aware that other traditional medicines and certain dietary supplements have in the past contained high levels of mercury.  Avoid products that have mercury warnings.  For products without warnings, consider contacting the manufacturer and asking if they contain mercury. 
  • Do not use skin-lightening, anti-aging, and acne treatment creams unless they have ingredients listed and you are certain that they do not contain mercury.

For more information:

General Mercury Fact Sheets and Resources:

Mercury in Fish:

Mercury in Products:

Mercury in Skin Creams:

Proposition 65:

  • California Environmental Protection Agency (CalEPA)
    Office of Environmental Health Hazard Assessment (OEHHA)
Posted March 2016
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