Mercury in the Health Care Environment |
On this page: What is
Mercury? How does Mercury get into the
environment?
What is mercury? Mercury, also known as quicksilver, is a naturally occurring element that has been used with great effectiveness in many industrial applications as well as household and commercial products. Mercury is a particularly useful metal because it can exist in a liquid state at ordinary temperatures. In small quantities, mercury conducts electricity, measures temperature and pressure, acts as a biocide and functions as a catalyst. How does mercury get into the environment? Mercury can enter the water, the air and soil as a result of natural and human activities. Scientists believe that atmospheric deposition contributes a large portion of mercury found in the environment. In addition to natural-occurring mercury emissions from volcanoes, soil and forest fires, human activities such as the burning of fossil fuels and incineration of municipal and medical wastes can release mercury gases and particles into the air. According to U.S. EPA, 870 pounds of mercury is added to the atmosphere in this country each day from human sources. Once mercury is released into the air, it circulates or can fall to the ground with rain and snow, landing on soil or in bodies of water. In the environment, mercury can be converted by microorganisms into methylmercury, which is an especially dangerous substance. How can mercury affect humans and wildlife? Like other metals in the environment, mercury is persistent and cannot be destroyed by combustion or bacterial degradation. The greatest risk to public health from mercury comes from the consumption of fish, which is the primary route of exposure for birds and mammals, including humans. In a lake or other water body, methylmercury is taken up by tiny animals and plants known as plankton. Small fish like minnows eat plankton and the methylmercury in them tightly binds to the proteins in the fish tissue. As larger fish eat more and more smaller fish, the concentration of mercury in their tissues rises. The older the fish, the greater potential for high mercury levels in their bodies. This process of increased pollutant concentration in each step of the food chain is called bioaccumulation; in other words, methylmercury accumulates as it is carried up the food chain to humans and wildlife. What are the hazards caused by mercury? Once mercury gets into the food chain, it can pose a health risk to humans and wildlife that consume large amounts of mercury-contaminated fish. The likelihood of negative health effects depends on the amount of mercury consumed, the duration of exposure and the sensitivity of the individual. In fish and other mammals, ingested mercury can lead to reproductive problems and even death. Researchers have found high levels of mercury in the livers and kidneys of dead eagles, minks and otters. In humans, the mercury in fish primarily affects the central nervous system and can cause reproductive effects and impaired development in children. Fetuses and children are most vulnerable to its effects. Mercury is the most frequent reason for fish consumption advisories in the U.S. It accounts for 60 percent of all advisories in fresh water bodies. Women who expect to become pregnant should follow state fish consumption advisories for high mercury levels or change their eating habits to reduce risk. No method of cooking or cleaning can reduce the amount of mercury that humans may ingest because it accumulates in muscle, not fat. What are sources of mercury in medical care settings? US EPA estimates that there is up to 50 times more mercury in medical waste than in general municipal waste. Mercury-containing products can end up in regular trash or in medical waste. When medical waste is put into infectious waste bags (red bags), it can be burned in medical waste incinerators. If mercury-containing waste is incinerated at high temperatures, it becomes gaseous and exits through smokestacks. Nationally, the incineration of medical waste is the fourth largest source of industrial merecury emissions. US EPA and state environmental agencies have recently developed regulations to further limit and control mercury and other toxic emissions from medical waste incinerators. For information on Illinois EPA’s regulations for medical waste incinerators, click here. It is important to note that these regulations not only provide requirements for facilities that operate medical waste incinerators, but also for those facilities who ship their medical waste to off-site commercial and private medical waste incinerators. Mercury is used in numerous products and procedures throughout hospitals, including patient care areas, pathology labs and clinical procedures. Mercury or mercury compounds are found in:
Mercury can also be found in lighting flourescent and high-intensity lamps, batteries used in medical equipment (defibrillators, hearing aids, pacemakers), thermostats and switches and cleaning solutions.
How can hospitals keep mercury out of medical waste? The most effective way to keep mercury out of the waste stream is to not use products containing mercury in the first place. Some hospitals have established programs that are phasing out the use of mercury containing equipment, devices and chemicals. They have also changed their procurement guidelines or agreements to purchase non-mercury products wherever feasible. When evaluating alternative products, it is important to consider the overall environmental impacts, including disposal costs and costs that result from cleaning up accidents. When adequate mercury alternatives are not available, mercury products should be disposed of properly and not placed in red bags, where they may be incinerated. Also it is important to have spill cleanup kits available wherever mercury is used. An individual should be designated and trained to clean up any spills. Finally, when mercury-containing products can’t be replaced, it may be possible to recycle the mercury. For example, batteries, fluorescent lamps and dental amalgam, should be recycled as much as possible. For a list of compaines that recycle Mercury-contaminating products, click here. What are the keys to successful mercury reduction efforts? A number of barriers exist which can keep hospitals and other health care facilities from taking advantage of mercury reduction alternatives, including:
A well-organized waste reduction program can be designed to overcome these barriers. To be successful the plan should include management, planning and monitoring elements to promote the development and implementation of specific mercury reduction projects. These elements should include the following:
The key to reducing mercury use at a hospital is commitment, involvement and teamwork. While management can determine priorities and set the tone of the facility’s mercury reduction efforts, it takes everyone to make it happen.
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