MERCURY IN THE ENVIRONMENT Ben Tong & Angellah Anyieni Chem. 450 Advanced Inorganic Chemistry Winona State University

What is Mercury Chemical symbol - Hg a silver-colored metallic element & very water soluble (toxic to living organisms) a liquid, conducts electricity, and mixes easily with other metals expands and contracts evenly with temperature changes evaporates to form mercury vapor, a colorless and odorless gas can cycle in the environment due to its ability to change forms

Entering in the environment…How? Atmosphere: evaporation from water and land as well as through coal-fired utility and incinerator emissions Soil: the natural breakdown of mercury- containing rocks, disposal of mercury in landfills, and atmospheric deposition Water: runoff, atmospheric deposition, and when mercury products are poured down the drain. Into living organisms: Once in the water cycle, mercury can convert to methyl mercury. It can accumulate in the tissues of fish and other organisms inhabiting mercury contaminated bodies of water, and may be carried up the food chain.

Mercury Hazards Through the diet (primarily through fish), Absorption, or through the inhalation of toxic elemental mercury fumes Health effects due to mercury exposure depend on the amount consumed, absorbed, or inhaled and the length and frequency of exposures Signs and symptoms in humans: coughing, shortness of breath, chest pain, vomiting, diarrhea, and fever Long-term exposure can result in shakiness, loss of muscle control, memory loss, kidney disease, and loss of weight

Control and Regulations Once mercury is released into the environment it is difficult to remove: Recycle button batteries or use mercury free ones Conserve electricity. The lesser the burning of coal and oil in electric plants (that naturally contain mercury), the lesser the mercury emitted into the environment

Use alternatives Thermometers: use alcohol or digital thermometers Old Alkaline-Type Batteries: use rechargeable Alkaline or Mercury-Free Batteries Some shoes that light up: use mercury-free shoes Contact lens solutions containing thimerosal: use solutions without thimerosal Lamps (Fluorescent, High Intensity discharge and mercury vapor lamps): use low mercury fluorescent Lamps, Sulfur lamps, low mercury sodium lamps (energy conserved by using these lights will reduce mercury emissions from coal & oil combustion)

Detection Methods Testing in water, air, soil samples or biological samples based on wet oxidation followed by a reduction step and then separate quantification of inorganic mercury compounds and organic mercury compounds Testing in industrial waste by oxidation, purge and trap, and cold vapor atomic fluorescence spectrometry

Mercury Cleanup ( always wear gloves ) Drain: mercury collects in sink trap so carefully remove sink trap and throw away in plastic bag labeled “mercury waste” Hard surfaces: use cardboard pieces to collect beads together and use a dropper to collect the beads. Throw away in plastic bag and label “mercury waste” Carpet or rug: cut out part of carpet/rug with mercury and throw away in plastic bag with label “mercury waste”

“Nevers” in mercury spillage Never use a vacuum cleaner to clean up mercury Never use a broom to clean up mercury Never pour mercury down a drain Never wash mercury-contaminated items in a washing machine Never walk around if your shoes might be contaminated with mercury

Ultimate Fate Mercury undergoes bioaccumulation. If an organism continually ingests mercury, its body burden reaches toxic levels. The bioaccumulation effect – the larger predatory game fish will likely have the highest mercury levels. Mercury concentrates in the muscle tissue of fish. So, unlike organic contaminants (for example PCBs which concentrate in the skin and fat, mercury cannot be filleted or cooked out of consumable game fish.

Two departments (controlling agencies): EPA – Environmental Protection Agency FDA – U.S. Food and Drug Administration

References ograms/Hazardous_Waste/mercury/index.asp accessed 12/04 ograms/Hazardous_Waste/mercury/index.asp US Department of the Interior URL: accessed 12/ /index.html accessed 12/ /index.html