Mercury: Health Impacts

People come into contact with mercury mainly through eating fish and small mercury spills, such as a broken thermometer. Reduce the majority of your contact with mercury by:

Following fish consumption advisories.
People can be exposed to mercury by eating fish or shellfish caught in contaminated waters. Follow the Wisconsin Department of Natural Resources’ (DNR) fish consumption advice to reduce your consumption of mercury.
​Cleaning mercury spills properly.
People can also be exposed by breathing mercury vapors, which can happen in the workplace or in homes where mercury is spilled. The DNR regulates the amount of mercury that can be released by industries. Although no standards exist for the amount of mercury allowed in the air of homes, we used a formula to convert workplace limits to suggested home limits. Based on the formula, we recommend levels of mercury vapor be no higher than 2 parts per billion (ppb).

Breathing mercury's vapors is very dangerous

When metallic mercury is touched it can slowly pass through the skin. People may experience a variety of health effects after short- and long-term contact with mercury.

Short-term:
  • Neurological effects, confusion, hand tremors
  • Chills
  • Chest tightness, bronchitis, pneumonia
  • Abdominal pain, nausea, vomiting, and loss of appetite
  • Bleeding gums
  • Leg pains and burning sensation in feet
  • Lung and kidney damage
  • Skin rashes
Long-term:
  • Blood in urine
  • Shaking
  • Burning pain in legs and feet
  • Sleep disturbance
  • Personality changes
  • Irritability
  • Memory loss

Other sources of exposure

Dental Fillings: Some dental fillings contain mercury and blood levels may be elevated for a short time after teeth are filled. People who work with exterior latex paint containing mercury can absorb mercury through their skin or by breathing in unsafe air in unventilated areas.

In the home: Organic mercury can be found in latex paints, and metallic mercury is sometimes used in religious rituals. It is also used as a fungicide and preservative for seeds, wood products, and paper products.

Contaminated Water: Mercury can enter the body when contaminated water is used for drinking or for preparing food. If a water supply is contaminated, people can absorb mercury as they bathe or use the water for other purposes. The state and federal drinking water standards are both set at 2 ppb of mercury. We suggest you stop drinking water containing more than 2 ppb of mercury. If levels of mercury are very high in your water, you may need to avoid washing, bathing, or using the water for other purposes.

Blood, urine, hair, and breast milk can all be tested for mercury. Normal levels of mercury in urine can vary, but are generally less than 15 micrograms per liter (µg/L). Doctors can do additional medical tests to check kidney and nervous system functions.

Seek medical advice if you have any symptoms that you think may be related to chemical exposure.

Last Revised: January 15, 2019