Mercury is a naturally occurring element that is found in several forms. As a metal, mercury is a shiny, silver-white, odorless liquid. It can also be found as a colorless, odorless gas if heated. Mercury combines with other elements, such as sulfur or oxygen, to form inorganic compounds (or “salts”), which usually take the form of crystals or powders. It can also combine with carbon to make organic mercury compounds such as methyl mercury, which is produced mainly by microscopic organisms in the water and soil. Metallic mercury is used in the production of chlorine gas and caustic soda, and is found in products such as thermometers, dental fillings and batteries. Mercury salts are sometimes found in skin lightening creams and antiseptic creams.

How You Are Exposed

• Eating fish or shellfish contaminated with methyl mercury. It builds up in the tissues of fish so larger and older fish tend to have the highest mercury levels.
• Breathing vapors resulting from spills, or vapors released from incinerators or industries that burn fuels containing mercury.
• Release of mercury from dental work or medical procedures.
• Working in an industry that uses mercury and breathing in contaminated air or allowing your skin to come into contact with mercury. Inorganic mercury enters the air from mining ore deposits, burning coal and waste, and from manufacturing plants.
• Products such as fluorescent bulbs, thermometers, cosmetics, older medicines, and traditional herbal remedies from other countries are also sometimes adulterated with mercury.

How Can Mercury Affect Your Health?

Mercury primarily affects the nervous system. Exposure to high levels of metallic, inorganic or organic mercury can cause permanent brain damage, as well as irreversible effects on the kidneys and developing fetus. Irritability, shyness, tremors, changes in vision or hearing, and memory problems may be noticed. Short-term exposure to high levels of metallic mercury can result in lung damage, nausea, vomiting, diarrhea, increased blood pressure or heart rate, rashes, and eye irritation. 

The EPA has reported that mercuric chloride and methyl mercury are possible human carcinogens. Research has found that mercuric chloride has caused increases in tumors in rats and mice and methyl mercury has caused kidney tumors in male mice, but there are inadequate data for all forms of mercury.

Very young children are more sensitive to mercury exposure than adults and mercury has been found to pass from the mother’s body to the fetus where it can accumulate. Another form of transmission is through breast milk. Some of the harmful effects that may result from mercury passing from a mother to a fetus includes: brain damage, mental retardation, incoordination, blindness, seizures, and inability to speak. The child may also develop problems of the nervous and digestive systems as well as in their kidneys.