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Broad Street Solutions
James Marx, RN, MS, CIC Editor
PO Box 16557
San Diego, CA 92176
(619)656-7887 Voice/FAX
jmarx@concentric.net
Repeated exposure to breathing mercury metal vapor affects the human brain, spinal cord, eyes, and kidneys. It may cause mood changes; inability to concentrate; memory loss; a fine shaking, tingling, or loss of feeling of the hand, tongue, or eyelid; discoloration of the cornea and lens of the eye; disturbances of vision; and kidney disease.
Swallowing mercury compounds can cause nausea, vomiting, and diarrhea. Severe kidney damage can occur. Some mercury compounds can cause irritation of the skin and eyes on contact.
Symptoms begin with cough, chest pain, trouble breathing, and upset stomach. Chemical pneumonia can then develop, which can be fatal.
Mercury is found in thermometers, manometers, vacuum pumps, switches, discharge tubes, dental almalgams, and as a component in chemical reactions.
Once vaporized, the lungs readily absorb elemental mercury from inhaled air. Much of the elemental mercury absorbed by the lungs reaches, and enters, the brain before it can be oxidized by the red blood cells. Oxidized mercury accumulates in the kidneys. At sufficient dose levels, mercury can cause salivation, coughing, chest pain, tremors, emotional instability, kidney damage and reproductive effects. High level acute doses and lower level chronic doses are both cause for concern.
Serious consideration should be given to replacing mercury with substitute materials when possible. Mercury free thermometers are available that are filled with non-toxic materials. Teflon coated thermometers are available that will help reduce spills from breakage.
Electronic or mechanical thermometers or manometers can be used in place of mercury filled devices. Manometers can be filled with other, non-toxic materials.
When breakage of an instrument containing mercury is a possibility, the instrument should be placed in an enameled or plastic pan that can be cleaned easily. Be sure the pan is large enough to contain the mercury. Transfers of mercury from one container to another should be carried out in a well ventlated space, and over a tray or pan to confine any spills. Do not handle mercury over sinks where it could spill down the drain. Always wear nitrile or latex gloves while handling mercury.
When a spill occurs, isolate the area to prevent people from entering the spill area and spreading the contamination. This is done with warning signs and barrier tape, locked doors, or other similar actions. Make the perimeter of the isolated area three feet beyond the most distant visible beads of mercury. Use the flashlight from the spill kit to help locate the smallest beads of mercury. Women who might be pregnant, or people with a history of kidney damage, should be kept away from the spill area until the clean-up is finished.
Next, determine if the spill is a simple spill. A simple spill is one caused by a thermometer, or other small device involving less than 30 milliliters of mercury (about one pound), where all of the mercury is accessible on a non-porous surface. If the spill is determined to be a simple spill, it should be cleaned-up immediately using the mercury spill kit. All facilities where mercury is used shall have access to a "mercury spill kit" for this purpose. Mercury spill kits, and refill materials are available from most lab safety supply companies. A typical spill kit will include treated sponges, mercury absorbing powder, water spray bottle, latex gloves, shoe coverings, flashlight, small dust pan, plastic scoop, and small plastic bags.
Prior to clean-up, remove all gold or silver rings, watches and bracelets. If mercury comes in contact with gold or silver jewelry, it can bond to the metal. Latex, or other impermeable protective gloves shall be worn during the mercury clean-up. Use caution and wear disposable shoe coverings so you do not contaminate your shoes with mercury during the clean-up.
Begin your clean-up at the outer perimeter of the spill. Work carefully, it is easy to miss contamination, or spread the contamination when the clean-up work is rushed.
Mercury should never be swept with a broom or vacuumed with an ordinary vacuum cleaner. These procedures will disperse mercury droplets, increase the airborne level of mercury vapor and contaminate the equipment used.
The preferred way to collect mercury is to dust the area of the spill with mercury absorbing powder. When used according to instructions, this powder will form a solid mercury-metal amalgam that is much safer and easier to handle than elemental mercury. Using a damp sponge, work the powder into a paste while scrubbing the contaminated surface. After the paste has dried, it can be collected with a squeegee or stiff card and placed into the plastic container for disposal. For vertical, or overhead surfaces, use mercury absorbent sponges to slowly wipe the surface to remove mercury.
Another way is to use an index card or rubber squeegee to form a pile that can be sucked up or amalgamated with mercury absorbing powder. Beads of mercury can be sucked up with a disposable pipette or a hand-operated vacuum pump.
Look very closely, using a flashlight to help illuminate the smaller beads. Mercury beads will often be pinhead size, or smaller. Re-clean the spill site and perimeter if necessary. Pay close attention to cracks and crevices that may hide small beads of mercury.
Place sponges, used powder, rags, shoe covers, and anything used for the cleanup into a plastic bag for disposal. Do not mix these items with any free mercury you may have collected. Seal and label the bag, and place gloves in the trash. Call the County Hazardous Waste division, found in the government section of the telephone book to arrange for disposal.
The job is finished when the visible mercury is removed, the area has been cleaned with mercury absorbing powder or sponges, and the waste and supplies are packaged. If there are any questions, take steps to keep others from entering or spreading the mercury contamination site, and call for assistance.
Mercury exposure is a potential hazard to your staff, residents and visitors .
James Marx © 1998