In January 2004, residents in northern Nevada found out first hand how dangerous mercury can be when dozens of middle school children in Gardnerville were exposed to the element and the vapors it gives off.

Less than a week later, severe poisoning from long-term exposure to mercury vapor sent a Las Vegas 17-year-old youth to a hospital's intensive care unit for a week, and the exposure may cause lifelong effects.

The quarter cup of mercury brought to the Gardnerville school by a student contaminated not only classrooms and a school bus, but the clothing and belongings of more than 50 of his classmates.

The state and federal governments spent more than $100,000 on decontamination efforts; the school was closed for more than a week; local businesses made donations to those students whose belonging were too contaminated to take home and had be destroyed.

In Las Vegas, EPA and Clark County officials spent weeks decontaminating the home the second youth lived in because of extremely high levels of mercury vapor. The youth had spent months playing with as much as a quart of mercury, spreading it throughout his house and backyard.

The vapor very nearly killed the boy. A substantial amount of his family's personal property had to be destroyed because contamination levels were so high, and the family's dog experienced severe mercury poisoning. Investigators are now looking at the possibility that friends took some of the mercury to their homes.

Extremely dangerous

Mercury has a lot of names: quicksilver, liquid metal, mercurio, that stuff from the 'Terminator' movies. It's number 80 on the periodic table of elements and looks like silver paint that doesn't melt.

Describe it however you want to, but make no mistake about it: elemental mercury isn't pretty and it isn't neat.

There are legitimate and safe uses for mercury, though many industries such as mining and paper production are moving away from mercury processes. Still, the silver liquid is found in thermometers, thermostats, fluorescent lamps, barometers and car switches.

But many people are not aware of the extreme danger of mercury when it is no longer contained in a thermometer or air-tight container.

All mercury spills, regardless of quantity, should be treated seriously. Metallic mercury slowly evaporates when exposed to the air. The air in a room can reach contamination levels just from the mercury in a broken thermometer - just a few drops.

When liquid mercury is spilled, it forms droplets that can accumulate in the tiniest of spaces and then emit vapors. 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 it.

The symptoms of mercury poisoning can include:

- impairment of peripheral vision

- disturbances in sensations - that 'pins and needles' feeling as well as numbness - usually in the hands feet and sometimes around the mouth

- lack of coordination of movements, such as writing

- impairment of speech, hearing, walking

- muscle weakness

- skin rashes

- mood swing, memory loss, and mental disturbances

Coming into contact with too much mercury this way can damage a growing brain, harming the way unborn and young children will be able to think and learn. It can also harm anyone's heart, kidneys, lungs, and immune system.

What you should do

There are some simple DO's and DON'T's to remember if, for example, a mercury thermometer breaks:

DO call your local health department and inform them of the situation.

DO immediately remove children from the area;

DO clean up the silver mercury beads by using one sheet of paper to carefully roll them onto a second sheet of paper, or use an eye dropper to collect it all. Then place the mercury into a plastic bag or airtight container. The paper and eye dropper should also be bagged in a zip-lock container.

DON'T try to soak it up with a towel or rag; doing so only spreads the mercury, breaking it up into smaller beads making it more difficult to find and remove.

DON'T use household cleaning products to clean the spill, particularly products that contain ammonia or chlorine. These chemicals will react violently with mercury, releasing a toxic gas.

DON'T vacuum carpeted floors contaminated with liquid mercury.

EPA and mercury decontamination

EPA has always been involved in removing mercury from the environment, from proposing and passing rules such as maximum achievable control technology and air transport regulations that will cut the amount of mercury vapor that industry and power plants emit, to sending trained emergency response teams to clean up homes and schools contaminated with mercury as we did in Nevada.

In early 2004, the EPA has worked very closely with the Nevada Department of Health and the Nevada Division of Environmental Protection (NDEP) in handling the mercury spills that occurred. NDEP is sponsoring a new program to collect and safely dispose of metallic mercury that Nevadans have in their homes.

The program will consist of collection events and will focus on household mercury waste in areas of the state where environmentally preferable recycling or disposal options are not readily available.

The events will likely be held at local landfills or similar facilities. We urge all Nevadans to participate in this program to remove this danger to public health and the environment.

Many other states have begun programs to collect mercury thermometers in an attempt to minimize the prevalence of mercury in homes. There are options available to consumers that are as reliable as mercury thermometers such as digital thermometers.