Mercury is pronounced as MER-kyoo-ree. Mercury was known to the ancient Chinese and Hindus and has been found in year old Egyptian tombs. Mercury is not usually found free in nature and is primarily obtained from the mineral cinnabar HgS. Spain and Italy produce about half of the world's supply of Mercury. Mercury can be used to make thermometers, barometers and other scientific instruments. Mercury conducts electricity and is used to make silent, position dependent switches.
Mercury vapor is used in streetlights, fluorescent lamps and advertising signs. Freshwater fish are a dietary staple for these native populations.
The provincial government has instituted hair analysis programs to monitor exposure. Methylmercury is also found in saltwater fish, again posing a dilemma to public health officials. The health benefits of even modest fish consumption are well known, particularly in the prevention of cardiovascular disease, so there is a delicate balance between achieving those benefits and the risk of too much mercury exposure.
The Native American populations of Quebec consume fish primarily during the summer months, and the mercury content of their hair reflects peak concentrations during the summer and lower concentrations during the winter. In contrast, populations that depend on ocean fish as their main source of protein tend to have relatively stable elevated levels of mercury in their hair. Fortunately, limited studies in both types of consumers suggest that they are not exhibiting even the most subtle signs of poisoning.
Studies of wildlife have come to different conclusions, however. In Maine and New Hampshire there is evidence that loons have experienced reproductive and immune problems due to cumulative poisoning from eating mercury-contaminated fish. In , a major epidemic occurred in Iraq in which 6, persons were hospitalized and almost died. In a well-intentioned humane response to famine, several nations shipped wheat grain intended for planting to Iraq. The seeds had been treated with a methylmercury-containing fungicide to hold down mold growth and preserve the viability of the seeds.
The seeds were also dyed red to serve as a warning, and attempts were made to inform the natives of the hazards of eating the seeds directly. Unfortunately, the warnings on the bags were in Spanish, because some of the grain had originated in Mexico, and the skull and crossbones, recognized by westerners as meaning poison, meant nothing to the Iraqis.
In the face of starvation many families milled the seeds directly into flour, and made and consumed the contaminated bread. There would have been no danger in eating grain grown from the treated seeds, because the subsequent crop would contain little or no methylmercury. The population of the United States has been fortunate in avoiding mass poisonings in the past, but there was one isolated series of cases in involving a single family in Almagordo, New Mexico.
The father worked in a seed store, which supplied local farmers, and he maintained a few pigs at home. He noticed a significant amount of wastage in the form of spilled seed grain at the store, and he began sweeping it up to feed to his pigs. Within a short time his pigs became obviously ill. Fearful of the loss of his investment, the father had them butchered, and he froze the meat for the use of his family. Three of them were eventually poisoned severely. Twenty-two years after this incident all surviving members of the family were carefully examined and tested.
In this interim the two youngest children had died, and autopsy and toxicological findings were available from one of these. Both were left in a vegetative state until their deaths. Facebook Facebook Twitter Twitter. Updated November 17, Featured Video. Cite this Article Format. Helmenstine, Anne Marie, Ph. Copper Facts: Chemical and Physical Properties. Liquid Elements on the Periodic Table. Palladium Facts Pd or Atomic Number The symbol used by Dalton for mercury is shown below.
Periodic table shop Printable table. Mercury: historical information.
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