Mercury is a naturally occurring chemical element, a heavy metal that remains in a liquid state at room temperature. It is recognized by its distinctive silvery-white, shiny appearance, often referred to as quicksilver. This unique element readily vaporizes into an odorless, colorless, and highly toxic vapor, even at ambient temperatures. Due to its extreme toxicity and the significant risks it poses to both human health and the environment, elemental liquid mercury is not readily available for purchase by the general public.
The Hazards of Mercury Exposure
Mercury exposure presents serious health and environmental risks, depending on its form, dose, and duration of exposure. Elemental mercury, when inhaled as a vapor, is particularly hazardous as it can be readily absorbed through the lungs into the bloodstream. Absorbed mercury can cross the blood-brain barrier, affecting the central nervous system. Exposure to mercury vapor can lead to neurological damage, manifesting as tremors, memory problems, sleep disturbances, and personality changes.
Ingestion of elemental mercury, such as from a broken thermometer, is less readily absorbed. However, inorganic mercury compounds are more soluble and can cause severe kidney damage and gastrointestinal issues. Methylmercury, an organic form found in fish, is highly toxic and can accumulate in the brain, posing a threat to developing fetuses and young children. Environmental contamination occurs through human activities like coal burning and mining, leading to mercury entering waterways where it undergoes bioaccumulation, increasing in concentration up the food chain.
Understanding Mercury’s Legal Status
The sale and distribution of elemental mercury are subject to stringent regulations in the United States, making it difficult for the general public to acquire. Federal agencies, including the U.S. Environmental Protection Agency (EPA), the Food and Drug Administration (FDA), and the Occupational Safety and Health Administration (OSHA), oversee mercury control. The EPA regulates mercury emissions and manages mercury waste. These regulations limit mercury concentrations in air, water, soil, food, and drugs to protect public health and the environment.
The FDA regulates mercury in food, drugs, and cosmetics, setting limits for its presence and often prohibiting its use in most consumer products. OSHA establishes workplace safety standards to minimize occupational exposure to mercury. The Mercury Export Ban Act of 2008 also prohibits the export of elemental mercury from the United States, aiming to reduce its global availability. These regulations restrict elemental mercury primarily to licensed professionals, research institutions, and specific industrial applications under strict controls, reflecting an effort to phase out mercury-containing products due to their inherent risks.
Common Uses and Safer Substitutes
Historically, mercury was used in many products and industrial processes due to its unique properties. It was commonly found in thermometers, where its consistent expansion provided accurate readings. Barometers and manometers also relied on mercury’s density for measuring atmospheric pressure and fluid pressure. Dental amalgam, a filling material, traditionally contained mercury and was valued for its durability.
Mercury was also used in electrical switches, fluorescent light bulbs, and industrial catalysts. However, concerns about mercury’s toxicity have driven the adoption of safer alternatives. Digital thermometers, aneroid barometers, and pressure transducers have replaced mercury-based devices for temperature and pressure measurement. Dental practices now widely use composite resins and other mercury-free materials for fillings. Light-emitting diode (LED) technology has largely superseded fluorescent lighting, providing energy-efficient and mercury-free illumination.
What To Do If You Find Mercury
If you find mercury, perhaps from an older broken device, requires immediate and careful attention to prevent exposure and environmental contamination. Avoid direct contact with the liquid mercury. If a spill occurs, ensure the area is well-ventilated by opening windows and leaving the room. Do not use a vacuum cleaner, broom, or mop, as these can spread the mercury or increase airborne concentrations.
For small spills, such as from a broken thermometer, use stiff paper or cardboard to push the mercury beads together and scoop them into a sturdy, sealable container, like a glass jar or heavy-duty plastic bag. Any contaminated materials, including broken glass or paper used for cleanup, should also be placed in this sealed container. It is crucial to label the container clearly as “Mercury Waste” and contact your local hazardous waste facility or public health department for guidance on proper disposal. Under no circumstances should mercury be disposed of in regular trash, poured down drains, or burned, as this can release harmful mercury into the environment.