Arsenic (Inorganic)

Why am I being warned about potential exposure to arsenic?

  • Arsenic (inorganic arsenic compounds) is on the Proposition 65 list because it can cause cancer. Exposure to arsenic and inorganic arsenic compounds can cause cancer of the lung, bladder, and skin. Such exposures may also cause cancer of the liver, prostate, and kidneys.
  • Arsenic (inorganic oxides) is on the Proposition 65 list because it can cause birth defects or other reproductive harm. Exposure to arsenic and inorganic arsenic oxides during pregnancy may affect a child’s development.
  • Proposition 65 requires businesses to determine if they must provide a warning about exposures to listed chemicals.

What is arsenic?

  • Arsenic is a naturally occurring chemical element in the Earth’s crust that can be in different forms. Some of the forms may cause health problems but other forms are not a health concern.
    • Inorganic arsenic is more harmful than the organic form.
  • Arsenic compounds were used extensively as pesticides and wood preservatives, but these uses have been mostly phased out.

How does exposure to inorganic arsenic occur?

  • Inorganic arsenic may be released to the air and found in some soil and water.
  • Some sources of inorganic arsenic include:
    • Tobacco smoke.
    • Some pressure-treated wood used in outdoor structures may have arsenic (arsenic use in wood preservation was phased out in 2004).
    • Some herbal medicine and other traditional remedies, especially from China and India.
    • Some inorganic arsenic may be detected in drinking water and food. California limits the amount of arsenic allowed in publicly supplied drinking water.
      • Seafood, especially shellfish, and some seaweed (especially hijiki, a short, black noodle-like seaweed) can take up arsenic from contaminated water.
      • Plant crops, including rice grown in soil with elevated arsenic levels, can absorb arsenic.
    • Some inorganic arsenic-containing pesticides are in limited use in California, including as wood preservatives and fumigants.

Ways you can be exposed to inorganic arsenic:

  • During pregnancy, arsenic can pass from the mother to the baby.

How can I reduce my exposure to inorganic arsenic?

  • Do not smoke. Do not allow children to breathe tobacco smoke.
  • Do not burn older pressure-treated wood (manufactured before 2004) and avoid using it for home projects.
  • Have children wash their hands after they play on or around wooden play structures or decks that have been treated with arsenic preservatives. If you own such a structure or deck, apply a sealant or coating every one to two years.
  • Limit contact with soil if you live in an area with a high level of arsenic in the soil. Wash your hands after contact with soil.
  • If you use well water, have it tested for arsenic contamination. If your water comes from a public supplier, it is already tested regularly for arsenic. You may wish to check with your water supplier regarding arsenic levels in your water.
  • Breastfeed your infant if you can. Tap water, particularly from unregulated private wells, and certain ingredients in some infant formula can be sources of elevated arsenic exposure for bottle-fed infants.
  • Include alternatives to rice-based foods in your infant’s diet.

For more information:

General Arsenic Fact Sheets and Resources:

  • US Department of Health and Human Services (HHS)
    Centers for Disease Control and Prevention (CDC)
  • National Institute of Environmental Health Sciences (NIEHS)
  • California Environmental Protection Agency (CalEPA)
    Office of Environmental Health Hazard Assessment (OEHHA)
  • Biomonitoring California

Arsenic in Products:

Scientific Information on Arsenic:

  • California Environmental Protection Agency (CalEPA)
    Office of Environmental Health Hazard Assessment (OEHHA)
  • US Environmental Protection Agency (USEPA)

Proposition 65:

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

    Related Product or Place

  • Food

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