Mercury is a naturally occurring element found in rocks, soil, water, air and living things. In its pure form (often called metallic or elemental), mercury is a shiny, silver-white, odorless liquid at room temperature. In addition, it can slowly vaporize into a toxic, colorless and odorless gas at room temperature.

Because mercury has unique properties, it has been widely used in industrial processes, scientific instruments, polyurethane floors, consumer products and certain cultural practices.

Some polyurethane or rubber-like floorings manufactured from about 1960 to at least 1980 contained mercury. Some of these floors used in school gymnasiums or cafeterias may release a small amount of mercury vapor into the air when scuffed or grazed. When it is inhaled, mercury vapor is easily absorbed by the body.

A number of other states have studied the problem of flooring containing mercury. Assessments by other state health departments have found that the mercury vapors typically emitted from this kind of flooring during normal activities in the gym did not harm students or anyone using the gym for an extended period of time. In many schools, proper ventilation can maintain concentrations below levels of health concerns. Proper ventilation requires a room or building to be mechanically ventilated with fresh air beginning at least two hours before the area is occupied and continuing throughout the period of use.

Urine and blood sample tests can help find out if you have been exposed to too much mercury. A urine test is preferred for measuring elemental mercury; however, it does not identify the source of mercury exposure. Further investigation would be needed to identify possible sources. Contact your primary care provider if you have concerns about being exposed to mercury. 

Elemental mercury vapor usually enters a person’s body through breathing in contaminated air.

Once in your body, elemental mercury can stay for weeks or months. Most of the elemental mercury absorbed into the body eventually leaves in the urine and feces, while smaller amounts leave the body in the exhaled breath.

The possible health effects for any person depends on how much mercury is present, how long and how that person is exposed, and how sensitive that person is to the effects of mercury, among other factors. Children and pregnant women are more sensitive to mercury health effects.

Exposure to very high levels of mercury vapor can cause brain, kidney and lung damage and can seriously harm a developing fetus. Some of the acute effects that may soon show after exposure to high concentrations of mercury are: headaches, chest tightness and coughing.

Some of the chronic effects after long-term exposure (usually more than one year) to mercury vapor are: anxiety, excessive shyness, sleeping problems, loss of appetite, irritability, fatigue, forgetfulness, tremors, changes in vision, and changes in hearing. Most of the effects of mercury resulting from prolonged lower level exposure go away, once exposure is terminated and the mercury has left the body.

For answers to questions about health effects, please contact the Arizona Department of Health Services, Office of Environmental Health by email at [email protected] or call 602-364-3118.