Waste ReductionMercury-Containing Equipment
The human health and environmental impacts of mercury are well established, and efforts are underway worldwide to minimize its damage. Veterinary facilities have traditionally been significant users of mercury-containing devices. Many are beginning to join these mercury reduction efforts by implementing mercury pollution prevention (P2) programs. The most aggressive facilities have managed to attain mercury-free status.
The Mercury Waste Reduction Hierarchy
Here is an outline of the generally accepted approach to mercury waste reduction:
- The highest priority is source reduction, which means not using mercury in the first place. In most cases mercury-free products that are equivalent to or better in performance than the old mercury devices are now readily available for virtually all applications in healthcare facilities.
- Recycling is the second priority. When adequate mercury alternatives are not available and mercury must be used, it may be possible to recycle it.
- Disposal of mercury should be the last resort, and should mainly be limited to spilled or otherwise contaminated material. Disposal is expensive and increases the potential of mercury being dispersed into the environment. Clean-up activities should follow established guidelines to minimize the volume of contaminated material, prevent inadvertent losses, and minimize potential health risks
The main obstacle to moving to a fully mercury-free facility is short-term cost. But when liability considerations and compliance costs are included in the assessment, it is hard to make the case for postponing the switchover. The presence of mercury exposes your facility to:
- immediate costs, including cleanup costs from spills, and citations from regulatory and accrediting organizations
- long term costs, such as legal actions by workers, patients, or members of the surrounding community thought to have been exposed to mercury used on site or found in your facility's waste stream.
Mercury-Free Alternatives
Most of mercury's unique advantages have become obsolete with developments in solid state electronics and materials science. Mercury-free products that are equivalent to or better in performance than the old mercury devices are now readily available for virtually all applications in healthcare facilities.
The following table lists the mercury-containing devices that typically account for a substantial fraction of the mercury in healthcare facilities. For each device, the table indicates the properties of mercury that have made it the material of choice for those devices in the past, and the alternatives that have since become available to perform the same functions without the use of mercury.
Device |
Properties |
Alternatives |
Thermometers |
Flow, thermal expansion coefficient, high boiling point |
Galinstan (uses a gallium-indium-tin alloy, otherwise similar in appearance and operation to the mercury version). A recent study finds Galinstan thermometers an "appropriate replacement" for mercury.
Digital (now available with comparable accuracy to mercury). Generally requires a battery, but solar cell models are available. |
Sphygmomanometers, barometers |
Flow, density, low vapor pressure |
Aneroid (No liquid: uses motion of bellows.)
Electronic (No liquid: uses solid state pressure sensor.)
Note: Calibration issues exist for all types of sphygmos, including mercury. |
Esophageal dilators |
Flow, density |
Tungsten powder in gel (tungsten is dense, more inert than mercury, and flows when dispersed in a gel) |
Electrical switches |
Flow, conductivity |
Mechanical and optical devices |
A few of these alternatives, such as the aneroid sphygmomanometer, have been around for decades, but have recently been improved to address issues such as durability, stability, and ease of calibration. Some were simply not available until very recently. But in all cases, there is no longer any technological barrier to phasing mercury out of healthcare applications.
Mercury Recycling
As mercury-containing devices are retired, the mercury should be recycled to the maximum extent possible rather than disposed of. Many states maintain directories or lists of approved mercury recycling companies. Use the Mercury Resource Locator to find recycling/exchange programs in your state.
Mercury Cleanup
Precautions should be in place to prevent mercury spills. In addition to the obvious health risks involved in a spill, there are also significant costs, which are documented in a fact sheet from a Sustainable Hospitals project. In several actual cases, spill costs for relatively minor incidents have generally amounted to several thousand dollars, and larger spills commonly involve tens of thousands.
When liquid mercury (also known as elemental or metallic mercury) is spilled, it forms droplets that can accumulate in the tiniest of spaces and then emit vapors into the air. Mercury vapor in the air is odorless, colorless, and very toxic. Most mercury exposures occur by breathing vapors, by direct skin contact or by eating food or drinking water contaminated with mercury.
Health problems caused by mercury depend on how much has entered your body, how it entered your body, how long you have been exposed to it, and how your body responds to the mercury. All mercury spills, regardless of quantity, should be treated seriously.
EPA provides mercury cleanup procedures, based on the quantity spilled.
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