What to Know About Mercury Poisoning

Medically Reviewed by Poonam Sachdev on November 23, 2021

Mercury is a heavy metal that's commonly found in the natural world. Mercury poisoning happens as a result of too much exposure to mercury. You can be exposed to mercury in a number of ways, and it can be extremely dangerous to your health.

Is Mercury Toxic?

Mercury is a toxic metal and has caused several large public health crises throughout the world, including in Japan and Iraq. However, depending on what form it's in, mercury can be harmful or non-threatening. For example, methyl mercury is quickly absorbed by the gut and takes root in many of your body’s tissues. On the other hand, mercury salts are less soluble and don’t have a noticeable effect.

How Do You Get Mercury Poisoning?

Mercury can be inhaled, absorbed through the skin or eyes, or ingested. The most common ways you might be exposed to mercury are through: 

Fish. When elemental mercury makes its way into water sources, it’s consumed by small fish. The small fish are eaten by bigger fish, and eventually, the predators at the top of the food chain end up with a lot of mercury in their tissues. Tuna, swordfish, and sharks are examples of fish that tend to be high in mercury.

Dental fillings. Modern-day dental fillings have a low level of mercury that is safe for many people. Nevertheless, there’s still a risk of ingesting harmful elemental mercury vapor.

Work environments. Working at a landfill, with mercury thermometers, or in a workplace with broken fluorescent and low-energy bulbs puts you at higher risk of mercury poisoning.

You probably won’t get mercury poisoning if you’re briefly exposed or if you come into contact with a harmless form of the metal. Some people worry about mercury exposure from vaccines. However, the form of mercury used in vaccines is quickly broken down by the body and doesn't pose a health risk.

Babies in the womb are more susceptible to mercury exposure. Pregnant people who consume fish and shellfish risk exposing their babies to mercury, which can affect their development. People who are exposed to mercury for extended periods of time may also experience more serious effects of exposure.

What Are the Symptoms of Mercury Poisoning?

Because mercury comes in many different forms — and because of the variety of places in your body where it can settle — there’s a wide range of symptoms you might experience. Symptoms of consistent, low-grade exposure to mercury include:

  • Tiredness
  • Anxiety
  • Depression
  • Tingly feelings due to damaged nerves
  • Weight loss
  • Memory loss
  • Concentration issues
  • Poor peripheral vision
  • Difficulty feeling your hands, feet, and mouth
  • Poor coordination
  • Low muscle strength
  • Mental health issues
  • Damaged kidneys
  • Difficulty breathing

At its worst, mercury poisoning can result in death. If you believe you’ve had prolonged exposure to mercury and are experiencing any combination of these symptoms, get in touch with your healthcare provider.

How Is Mercury Poisoning Diagnosed?

It can be difficult to diagnose mercury poisoning. Blood and urine testing are necessary but don’t offer a complete picture of the extent of mercury poisoning. In addition to these tests, your doctor will ask you many questions to try to arrive at a diagnosis. They might include:

  • Do you have many vague symptoms that are similar to common signs of mercury poisoning?
  • Is there a more likely explanation for these symptoms?
  • Do you have a background of high possible exposure to mercury, from multiple dental fillings, a diet high in seafood, or a career that exposed you to mercury?
  • Do you have a family history of diseases with links to mercury exposure, like Alzheimer’s disease or Parkinson’s disease?
  • Do you have any medical conditions that would make it difficult for your body to fight off mercury and similar heavy metals?

If it’s likely that your symptoms point to mercury poisoning, your doctor may decide to move on with treatment.

How Is Mercury Poisoning Treated?

Regardless of what kind of mercury you were exposed to, you will probably be treated with chelation therapy. During chelation therapy, compounds that are designed to bind to the mercury are inserted into your bloodstream. As these drugs do their work, your body eliminates the mercury.

How Do You Reduce Your Exposure to Mercury?

Take note of the things in your environment that could expose you to mercury. Then, do what you can to eliminate or minimize your exposure. Talk to your doctor if you have questions about your symptoms or had any recent incidents that resulted in direct exposure to mercury.

Show Sources


Agency for Toxic Substances and Disease Registry: "Medical Management Guidelines for Mercury."

Better Health Channel: “​​Mercury exposure and poisoning.”

Journal of Environmental and Public Health: “Mercury Toxicity and Treatment: A Review of the Literature.”

United States Environmental Protection Agency: “Health Effects of Exposures to Mercury.”

World Health Organization: "Mercury and health."

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