Mercury contaminated rooms

Two very different kinds of pump fluids have been employed in diffusion pumps. For many years, mercuiy diffusion pumps, were used in small laboratory-bench glass vacuum systems. Mercury pumps are now seldom used owing to the health hazards associated with mercury and the high probability of contamination of the vacuum system with mercury unless a cold trap is used (the vapor pressure of mercury at room temperature is —1.5 mTorr). The oil diffusion pump eliminates the safety hazard and can serve for both small glass and larger metal vacuum systems. 

All materials and tools used during the MIP experiments and the cleanup procedure should be managed as mercury-contaminated waste. Thus, gloves and shoes protections must be stored in dedicated, sealed trash containers and all contaminated equipment and clothing (lab coats, etc.) must be kept in the closed room. 

Regulatory facts ATSDR - minimal risk level (MRL) - inhalation 0.2 ig/m3 General facts long history of use, liquid silver evaporates at room temperature, bacteria convert to organic methyl mercury Environmental global environmental contaminant Recommendations avoid, recycle mercury-containing devices... 

A study of mercury in Lake Michigan found levels near 1.6 pM (1.6 X 10 12 M), which is two orders of magnitude below concentrations observed in many earlier studies.5 Previous investigators apparently unknowingly contaminated their samples. A study of handling techniques for the analysis of lead in rivers investigated variations in sample collection, sample containers, protection during transportation from the field to the lab, filtration techniques, chemical preservatives, and preconcentration procedures.6 Each individual step that deviated from best practice doubled the apparent concentration of lead in stream water. Clean rooms with filtered air supplies are essential in trace analysis. Even with the best precautions, the precision of trace analysis becomes poorer as the concentration of analyte decreases (Box 5-2). 

The mercury surface is probably the best characterized surface with respect to its electric properties. The explanation is that mercury is one of the few metals that is liquid at room temperature. Since it is a metal a voltage can easily be applied. Since it is a liquid the surface tension can be measured simply and precisely. Then the surface charge can be calculated with the help of the Lippmann equation. Additionally, a fresh surface free of contamination can be continuously produced. 

Contaminant vapors are normally formed by allowing the liquid to evaporate into the air. A significant source of mercury poisoning is from worker exposure in laboratories where mercury has been spilled, trapped in cracks, and then evaporates at room temperature to exceed the TLV of 0.05 mg/m3. 

Nails have been used in the biomonitoring of various elements, for example, arsenic, fluoride, mercury, nickel, and thallium. The advantages of analyzing nail samples include the easy and noninvasive collection of the samples, the small sample size required for analysis, and their easy storage at room temperature. The great toenail, which reflects body exposure in the previous 12 months, has been stated to be the nail best utilized for biomonitoring because it is less exposed to external contamination. 

If small amounts of mercury are spilled, be very careful cleaning it up. Do not try to vacuum spilled metallic mercury. Using a vacuum cleaner to clean up the mercury causes the mercury to evaporate into the air, creating greater health risks. Trying to vacuum spilled metallic mercury also contaminates the vacuum cleaner. Also, take care not to step on the mercury and track it into other areas of the home. Metallic mercury vapors are very toxic and have no odor. Do not remain unnecessarily in that room, and try not to let metallic mercury contact your eyes, skin, or clothing. If you think you have been exposed directly to metallic mercury, wash yourself... 

Surface mercuiy usually is in the metallic form. Simple washing of the surface can be very effective. High-pressure water can remove mercury quickly splash containment is necessary. Steel and rubber-lined pipework can be retorted or cleaned with HCI/CI2 or NaOH/H2C>2. These solutions oxidize the metal to the soluble Hg +. Heavily contaminated steel will sweat mercury. Lott [19] points out that broken concrete from a cell room floor also can sweat mercury if allowed to stand overnight. Components should be stored with this in mind. Liquid droplets can be collected. The storage area should be ventilated because of evaporation of the mercury. Buswork and copper fabrications are protected by surface films and usually are not seriously contaminated with mercury. Surface washing is good practice before recycle. Copper braid or flexible strips can be more heavily contaminated and require treatment in a mercury distillation oven. 

Mercury is a silvery, shiny transition element that is a liquid at room temperature. Mercury can enter the body through inhaled mercury vapor, contact with the skin, or foods or water contaminated with mercury. In the body, mercury destroys proteins and disrupts cell function. Long-term exposure to mercury can damage the brain and kidneys, cause mental retardation, and decrease physical development. Blood, urine, and hair samples are used to test for mercury. 

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