Mercury, the only metal which can be found in liquid form at room temperature, is a heavy, silvery-white d-block element. Mercury exists in different chemical forms: elemental (or metallic), inorganic, and organic. Methylmercury, the most predominant form of organic mercury, is the form that poses a risk through fish consumption. Another organic mercury compound, ethylmercury, is a metabolite from thimerosal. Since the 1930’s, thimerosal, which is approximately 50% mercury by weight, has been used as a preservative to prevent bacterial and fungal contamination in vaccines. It wasn’t until the late 1990’s that concerns were raised about exposure to ethylmercury, especially for infants who receive many vaccinations within their first year of …show more content…
One of its most unique characteristics is that it is the only metal that is a liquid at standard conditions for temperature and pressure. Its chemical symbol, Hg, comes from the Latinized form of a Greek word meaning water-silver. Mercury is an extremely rare element in the Earth's crust, having an average crustal abundance by mass of only 0.08 parts per million. It is found mainly in cinnabar ore (HgS) in Spain and Italy. This mercury ore is bright scarlet to brick-red in color due to the naturally occurring mineral pigment, vermilion. Mercury can be extracted from cinnabar in a current of air and condensing the vapor. The equation for this extraction …show more content…
Elemental mercury, which is a liquid at room temperature is less toxic than inorganic or organic bound mercury. However, it can easily evaporate. Breathing in large amounts can cause harm. Inorganic mercury compounds are formed when mercury combines with elements such as chlorine, sulfur, or oxygen. Mercury salts can cause toxic effects if they are ingested. The high toxicity of mercuric ions can be explained by the high affinity to sulfhydryl groups of amino acids, which are building blocks for enzymes. In organic mercury compounds, mercury is covalently bound to carbon. Organic mercury is the most dangerous form of mercury to human health. The most common organic mercury compound in the environment is methylmercury which bioaccumulates in fish and can be harmful if
Another concern with vaccines is the addition of a form of mercury called thimerosal. “Thimerosal is best known as a preservative used in some vaccines to keep them from becoming contaminated”
Hat manufacturers once used a bright orange mercury wash to separate fur from pelts, and the common hatters who dredged around in the steamy vats, like the mad one in Alice in Wonderland, gradually lost their hair and wits. Eventually, I realized how poisonous mercury is. That explained why Dr. Rush’s Bilious Pills purged the bowels so well: the body will rid itself of any poison, mercury included. And as toxic as swallowing mercury is, its fumes are worse. They fray the “wires” in the central nervous system and burn holes in the brain, much as advanced Alzheimer’s disease does.
Burbacher and Shen did a study with forty-one infant monkeys at the Washington National Primate Research Center’s Infant Primate Research Laboratory (Burbacher). The birth weights of each infant monkey were within the normal range; the average birth weight was 341 grams and the range was 225-420 gram. Monkeys were weighed daily throughout the study, and any clinical problems were recorded. This experiment mainly compared the natural mentality and brain distribution of infant monkeys and the inorganic mercury in infant monkeys after the thimerosal were exposure with those exposed to methylmercury (MeHg). Monkeys were injected thirmerosal at birth and 1, 2, 3 weeks of age so they could get exposed to the MeHg. Infants were divided into
Karen Nelson, Neuroepidemiology Branch, National Institute of Neurological Disorders and Stroke; and Margaret Bauman, Children’s Neurology Service, Harvard Medical School conducted a study on neuropathology of mercury toxicity. Nelson and Bauman asserted ethylmercury lacks the active transport mechanism across the blood-brain barrier that other found available to methylmercury however; they provided no evidence to support this assertion. The L system is the major transport
For instance, certain seafoods are known to have high concentrations of mercury. The same can be found inside of certain dental fillings, such as silver fillings or mercury amalgrams.
Another claim anti-vaxxers make is that vaccines contain mercury which is toxic to humans (Ross, np). Thimerosal, which was in multi-dose vaccines to prevent bacteria growth, did in fact contain traces of mercury (Ross, np) (CDC, np). However, there are two types of mercury: methylmercury and ethylmercury (CDC, np). Methylmercury, which is found in some kinds of fish, is toxic to humans in high doses, while ethylmercury is cleaned out of the body rapidly and is less likely to cause any harm, especially at low doses (CDC, np). Thimerosal contained a very low dose of ethylmercury, and studies showed it would not be toxic to humans, aside from some minor side effects such as redness or swelling after injection (CDC, np). Even so, the FDA decided to remove thimerosal from vaccines back in 2001 (Ross, np).
Once released into the environment, mercury is free to be taken up by plants and animals but is not toxic unless transformed through bacterial or chemical processes into its organic form, the most famous of which is methylmercury [6], [8], [10] Methylmercury impacts several critical organ systems and particularly toxic to the development of the fetus [11]. It also bioaccumulates in living organisms, which leads to higher levels of methylmercury with each increasing trophic level [10], [12], [13]
These toxins more often than not can have fatal consequences. Mercury is definitely one of the number one most dangerously used elements in our history. The first written record of this element is credited to Aristotle Often called the element of the ancients, mercury was dated back to as far as the 15th century BCE when it was found in ceremonial cups in Egyptian Tombs (Czaika). It is known that the Romans were the first to actually mine and use this element for everyday needs. Even at these times humans were aware of the fact that the element was poisonous. They had a mine in Spain that was worked by slaves, prisoners, and other undesirables. After the mine was dry they would use it as a prison system for the workers. Most of them would die very slow and painful deaths, bringing a long end to a short life (Sloane). In ancient China, mercury was used for a variety of medical needs. From a contraceptive, to a cough serum, to a remedy for unknown sexually transmitted diseases (Kok). People would consume mercury as if it was candy. This practice also spread to India. People did not understand the harmful toxins that they were ingesting.
Thimerosol is a “mercury-containing preservative...removed from most vaccines (Sears, 53).” The reason it was removed from most vaccines was due to the fact that “mercury in vaccines given to infants by six months of age was about 87 times the level thought to be safe (Sears, 53).” Thus the replacement for mercury in most vaccines became aluminum. Compared to mercury, aluminum is more common in the air, soil and food supply (Sears, 46). It is for this reason, presumably, that Aluminum came to be used as an adjuvant in vaccines to “help them work better (Sears, 46).” However, the promise of aluminum in vaccines is something that Sears calls into serious question. The main argument which Sears advances throughout their article is that, even though the human body may process aluminum through the liver
He explains that the recommended level of mercury is .4 ppm (parts per million). However, the piece that he measured had 2000 ppm of mercury. That is 5000 times higher than the levels deemed to be safe for eating. Even though this meat exceeds the regulation requirements for mercury, it is still allowed to be sold without the public knowing. The movie goes on to explain what exactly mercury can do to a person by bringing up an event that happened in Minamata, Japan. There, a factory was dumping waste into the local water source and polluting it with toxic levels of mercury. The people who were most affected were the pregnant women’s fetuses; they were most susceptible to the toxins, and contracted what the locals called Minamata’s disease, or extreme mercury poisoning. These children were born with major birth defects, such as blindness, lack of motor control, muteness, and deafness. For the longest time, though, no one knew why this was happening. They did not know where it came from. Studies carried out much later revealed that it was in fact high levels of mercury that had poisoned the region’s
Mercury is a transition metal that is also known as “quicksilver.” No one is sure who discovered this element. Mercury has been used since ancient times; the Chinese, Egyptians, and the Hindus have been known to use mercury. In 1500 B.C. mercury was found in ancient Egyptian tombs. There also has been writings found that have said “liquid-silver” and “water-silver” written by Aristotle in the fourth century B.C.
How does Methylmercury form from Hg(II)? Hg0 or Hg(II) is released from mines and sent into the atmospheric, then they are deposited into the oceans, where the excess Hg0 can be oxidized into Hg(ii). After Hg(II) reacts with light and microorganism in the oceans, it creates Ch3Hg eventually getting into fishes, such as, tuna and swordfishes.
The article “Our Preferred Poison” in the March 2005 issue of Discover magazine brings up the issue dealing with mercury poisoning. The author, Karen Wright, writes, “Mercury is unimaginably toxic and dangerous. A single drop on a human hand can be irreversibly fatal. A single drop in a large lake can make all the fish in it unsafe to eat.” This was the opening statement in the article which first grabbed my attention, because I had not thought mercury to be such a deadly substance. After all, it is used in thermometers, so I hadn’t thought it to be as fatally toxic as Wright claims it to be.
The contamination has affected the marine population at large but few of bacteria have found way out to tolerate such high concentration of mercury. Such bacteria have been discovered way back in 1960’s by Moore, where he reported to found an operon called as mercury operon or mer operon which is found to be integrated on plasmid, transposons, etc., which harbors the efficiency to withstand mercury contamination. Further various researches were made and it was found that mer operon primarily have two genes called merA which encodes for mercury reductase enzyme which breaks down inorganic form of mercury (Hg2+) to less toxic and volatile form of mercury (Hg0), which is released in environment and the other gene called merB which acts on organic form of mercury (CH3Hg+) to convert it into Hg2+.Thus two major mechanisms are found to be associated with mercury
People can come in contact with mercury in a number of ways. There is increased risk of mercury exposure in the dental, health and chemical industries. People are also at risk of consuming an unsafe amount of mercury if they eat certain things in excess amounts, such as more than 6 ounces of albacore tuna per week, or over 12 ounces of fish like shrimp, canned tuna, salmon, pollock or catfish. Exposure to mercury can cause brain damage, kidney damage, lung damage and various digestive system problems (McCoy). Perhaps the person most vulnerable to mercury poisoning is the pregnant woman and her unborn fetus. Trauma caused to infants and children as a result of