Mercury+2

 =Mercury (Hg) =



= = = ** History of use of the substance ** = Mercury was known to ancient Chinese and Hindus before 2000 BC and was found in Egyptian tombs dated from 1500 BC. It was used to form amalgams of other metals around 500 BC. The Greeks used mercury in ointments and the Romans used it in cosmetics.(unfortunate for them!)

Today, mercury is used in the following ways:


 *  Laboratories for making thermometers, barometers, diffusion pumps, and many other instruments.
 *  It is used for mercury switches and other electrical apparatus.


 * It is used as an electrode in some types of electrolysis and for making batteries (mercury cells).


 * Gaseous mercury is used in mercury-vapour lightbulbs and advertising signs.


 *  Mercury is also the basis of dental amalgams and preparations. (although many dentists are phasing it out).

= = =** Why is it considered hazardous? **=

Mercury, at high levels, may damage the brain, kidneys, and developing fetus. = ** Where might we be exposed to this substance? ** =   = = =** Short term/long term health effects of exposure? **= 
 * Eating fish or shellfish contaminated with methylmercury. [[image:http://www.hgtech.com/images/MISC/CYCLEHG.GIF width="348" height="364"]]
 * Breathing vapors in air from spills, incinerators, and industries that burn mercury-containing fuels.
 * <span style="font-family: Tahoma,Geneva,sans-serif; font-size: 110%;">Release of mercury from dental work and medical treatments (Thimerosal, an additive to vaccines, contains mercury)
 * <span style="font-family: Tahoma,Geneva,sans-serif; font-size: 110%;">Breathing contaminated workplace air or skin contact during use in the workplace (dental, health services, chemical, and other industries that use mercury).
 * <span style="font-family: Tahoma,Geneva,sans-serif; font-size: 110%;">Short-term exposure to high levels of metallic mercury vapors may cause effects including lung damage, nausea, vomiting, diarrhea, increases in blood pressure or heart rate, skin rashes, and eye irritation.
 * <span style="font-family: Tahoma,Geneva,sans-serif; font-size: 110%;"> Exposure to high levels of metallic, inorganic, or organic mercury can permanently damage the brain, kidneys, and developing fetus. Effects on brain functioning may result in irritability, shyness, tremors, changes in vision or hearing, and memory problems.
 * <span style="font-family: Tahoma,Geneva,sans-serif; font-size: 110%;"> In terms of long-term exposure, the EPA has determined that long term exposure to mercuric chloride and methylmercury are possible human carcinogens.