IN Lately more and more often in the composition of everyday goods for every person there is such chemical element like mercury. Given its controversial characteristics and not entirely beneficial effect on human body, we decided to pay some attention to this material. In this article we want to consider how popular this element is in current production, and how safe it is for humans.
Mercury is still actively used to make thermometers. In addition, mercury-quartz and fluorescent lamps are completely filled with mercury vapor. The mercury contacts in turn become position sensors. Another application in modern production metallic mercury is found, which is used in the production of a number of important alloys. By the way, if you are choosing a comprehensive insurance calculator, we recommend using it on the website of the insurance company Ingosstrakh - www.ingos.ru.
It is worth noting that use of mercury in modern industry has been used for a long time. Previously, a variety of metal amalgams, in particular gold and silver amalgams, were widely used in jewelry, in the manufacture of mirrors and dental fillings.
Mercury also found its place in the creation of technology - it was often used for barometers and pressure gauges. In addition, mercury compounds were often used as an antiseptic (sublimate), as a laxative (calomel), and even in the hat industry. However, due to the fact that this element is highly toxic, by the end of the 20th century, mercury was practically forced out of these areas of production.
However, no matter how it was there before, today mercury still finds its way use of mercury in modern industry. The mercury-thallium alloy, for example, is still used for low-temperature thermometers. Metallic mercury becomes a cathode in order to obtain a series of active metals, chlorine and alkalis, in individual chemical current sources, as well as in reference voltage sources.
Mercury is often introduced during the processing of secondary aluminum and gold mining. It is also sometimes used as a working fluid in heavily loaded hydrodynamic bearings.
There is also a reflection in the form of ballast in submarines and controlling the roll, as well as the trim of some devices. A promising direction is the use of mercury in alloys with cesium as a highly efficient working fluid in ion engines.
As we can see, mercury is still held in high esteem in modern industry. However, practice last days begins to demonstrate a slightly different attitude. Thus, recently the countries participating in the UN negotiations, after 4 years of negotiations, agreed on a new international document, which solves the problem of mercury pollution environment. This agreement provides for a gradual phase-out of the use of mercury in modern chlor-alkali production.
Mercury (English Mercury, French Mercure, German Quecksilber) is one of the seven metals of antiquity. It was known at least 1500 BC; even then they knew how to obtain it from cinnabar. Mercury was used in Egypt, India, Mesopotamia and China; it was considered the most important raw material in the operations of the sacred secret art for the production of life-prolonging drugs called immortality pills. In the 4th - 3rd centuries. BC. Aristotle and Theophrastus mention mercury as liquid silver (from the Greek water and silver). Dioscorides later described the production of mercury from cinnabar by heating the latter with coal. Mercury was considered the basis of metals, close to gold, and therefore was called mercury (Mercurius), after the name of the planet Mercury closest to the sun (gold). On the other hand, believing that mercury was a certain state of silver, the ancient people called it liquid silver (from where the Latin Hydrargirum comes). The mobility of mercury gave rise to another name - living silver (lat. Argentum vivum); the German word Quecksilber comes from the Low Saxon Quick (live) and Silber (silver). It is interesting that the Bulgarian designation for mercury - zhivak - and the Azerbaijani one - jivya - were probably borrowed from the Slavs.
In Hellenistic Egypt and the Greeks, the name Scythian water was used, which allows us to think about the export of mercury at some period of time from Scythia. During the Arab period of the development of chemistry, the mercury-sulfur theory of the composition of metals arose, according to which mercury was revered as the mother of metals, and sulfur (sulfur) as their father. Many secret Arabic names for mercury have been preserved, indicating its importance in alchemical covert operations. The efforts of Arab and later Western European alchemists were reduced to the so-called fixation of mercury, that is, to transform it into a solid substance. According to alchemists, the resulting pure silver (philosophical) was easily transformed into gold. The legendary Vasily Valentine (XVI century) founded the theory of the three principles of alchemists (Tria principia) - mercury, sulfur and salt; this theory was later developed by Paracelsus. In the vast majority of alchemical treatises outlining methods of transmutation of metals, mercury comes first either as the starting metal for any operations, or as the basis of the philosopher's stone (philosopher's mercury). Of the secret alchemical (partly of Arabic origin) or mystical names for mercury, we cite the names nitrogen (Azoth, or Azoq), Zaibac, Zeida, Zaibar (Saibar), Ventus albus, Argentum vivum, etc. Alchemists distinguished many types of mercury and accompanied its general name Mercurius various epithets (mercury metals, minerals, mercury sir, weak, etc.). The origin of the Russian and Slavic names for metal (Czech rtut, rdut, Slovenian ortut, Polish rtec, trtec) is unclear. In ancient Russian literature, this word is found already in the 12th century. Philologists believe that it is associated with the Turkic utarid, meaning planet Mercury. This assumption is supported by the alchemical name Tarith - according to Ruland: “the same as Ruscias" (Russian?). A. M. Vasiliev believes that the connection with the Turkic root indicates the influence on our ancestors of ancient Chaldean views that compared metals with planets. At one time, the author of these lines pointed out the possibility of a purely Slavic word formation of the name mercury from ore, rudra or ore, denoting red color, blood, red paint and generally red. This comparison is based on the red color of cinnabar - the compound from which mercury was obtained It is known that cinnabar has been mined since ancient times in some areas of modern Donbass.This issue requires additional research.
Why is mercury from a thermometer dangerous for humans? This is the question a person asks when faced with a deformed mercury thermometer. To measure accurate body temperature, thermometers using alcohol, glycerin, mercury, as well as electronic devices have become widespread.
As practice shows, mercury thermometers show the most accurate readings of body temperature, which is associated with the high thermal conductivity of mercury and the almost linear expansion coefficient of the metal.
Along with such an important advantage, mercury-based thermometers have a very harmful and even dangerous drawback - the toxicity of the substance and the ability to accumulate in the body, which can even lead to fatal cases of poisoning.
At home and even in hospital conditions we received wide application namely mercury thermometers, since they give an error of only 0.01°C. This error is achieved due to the amazing properties of the liquid metal - mercury.
The characteristics of mercury are quite remarkable. The melting point of this chemical substance is only 38.8°C, which means that under normal conditions it is in liquid form. Like all metals, mercury in a thermometer expands when the temperature rises, and contracts when the temperature drops.
Also, liquid mercury does not have the ability to moisturize and remain on the glass from which thermometers are made. This allows you to achieve high precision measuring tool by using glass tubes of very small cross-section.
It is important to remember that mercury is nothing more than a highly toxic poison and belongs to the 1st class of very toxic substances.
The above properties make this metal indispensable in the manufacture of thermometers. However, mercury and any compounds with it are quite toxic and poisonous. Because of this reason, some countries have even abandoned the use of mercury-based thermometers.
If you handle a mercury thermometer correctly and carefully, if you store it in a place protected from children, in a special case, and use it only under adult supervision, such an instrument is not dangerous.
But in the case when a thermometer with mercury does break, both glass fragments and leaking mercury from the glass tube pose a danger to the human body. This substance is characterized by a very low melting point, which is not typical for other metals - 38.8°C, and it evaporates already at a temperature of +18°C.
It must be remembered that mercury evaporates both in the open air and under water.
Liquid mercury vapors are very toxic, since when inhaled, the vapors enter the lungs, then the mercury is oxidized and, in its oxidized state, negatively affects the condition of the body. The ions of the element, which are formed during the oxidation of the metal, are very poisonous.
A mercury thermometer may contain 1 to 2 grams of dangerous liquid mercury. This volume of pure mercury outside the glass tube will be enough to poison the human body to varying degrees of severity. Symptoms of such poisoning may not immediately appear, since the metal is characterized by accumulation properties.
Depending on the duration of exposure and concentration of mercury, the following types of poisoning are distinguished:
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Mercury mainly enters the human body through toxic vapors through the lungs. When we're talking about If there is a large spill of mercury, then intoxication can also occur through the mucous membranes and pores of the skin. Basically, metal has a detrimental effect on nervous system, respiratory tract and kidneys.
If the substance enters the human body with food, then it does not have a significant effect, since almost all of it is excreted by the body through the intestines without absorption into the blood. The remaining part is excreted over a long period of time through the kidneys.
It must be remembered that mercury has a neurotoxic effect on the human body, which occurs in the form of destruction of nerve cells.
People with weakened immune systems, as well as young children and pregnant women are especially sensitive to the effects of vapors.
Prolonged penetration of small but dangerous doses of mercury into the body can trigger the onset of severe inflammatory processes in important organs and systems. In general, mercury vapor intoxication leads to pneumonia, paralysis and complete blindness.
Considering all aspects of the negative, it is necessary not only to identify signs of mercury exposure in a timely manner, to properly clean up and dispose of spills, but also to immediately provide emergency assistance.
Mercury accumulates in the body and is not eliminated from it. This is what chronic poisoning is associated with. What symptoms are observed? 
If toxic mercury accumulates in the body for years, then performance, memory, and concentration gradually deteriorate, and mental illness occurs. Sometimes hair falls out, teeth become loose, and some diseases become chronic. Such symptoms appear after several years.
The problem of a broken thermometer becomes especially serious if there are small children at home. They are especially susceptible to poison, since the child’s body cannot fully resist it. If in the family Small child, you need an electronic thermometer.
From a broken thermometer the following is observed:
If these symptoms appear, you need to call an ambulance. Usually, gastric lavage is performed to remove mercury oxide and relieve signs of intoxication. If prompt medical attention is not forthcoming, you can induce vomiting yourself. According to statistics, in 65% of cases it is mild poisoning.
Mercury poisoning can only be treated in a hospital setting. Since mercury from a broken thermometer is very dangerous, first aid should be given immediately at home. medical care. It consists of alleviating the condition of the poisoned person and consists of the following measures:
The above measures should be carried out if the victim is fully conscious. When a person is unconscious, he must be quickly freed from constricting clothing and placed on his side. You should also prevent the tongue from sticking and ensure the supply of fresh air.
In the event that the mercury thermometer in medical institution, at work or at home, you must call emergency services and follow the following recommendations:
Work on collecting toxic metal must be carried out quickly, especially if the room is warm. Otherwise, the mercury will begin to evaporate and cause damage to the respiratory system.
Almost every home medicine cabinet contains a mercury thermometer. At correct use This attribute is completely safe for humans. If the thermometer accidentally breaks, do not panic; it is important to collect all the metal balls as soon as possible.
Why expose yourself and your loved ones to unnecessary risk? Today we are surrounded by many harmful substances, with which it is saturated modern world. There are safe electronic thermometers, which accurately and quickly indicate body temperature.
The thermometer looks like a flat stick with fine tip and a display on the body. He gives evidence within a minute after contact with the body. It will not break, is reliable and accurate. Duration of work: from 2 to 5 years. So mercury thermometers have already exhausted their usefulness and will soon disappear completely.
Therefore, when making a choice at a pharmacy, buying drugs or medical devices, read the instructions and inquire about their safety. AND stop buying a mercury thermometer. Take care of your health and the health of your loved ones and do not expose yourself to unnecessary risks.
Mercury is a light silvery metal in the sixth period of the periodic table. This substance is in the zinc subgroup with atomic number 80. Main feature mercury is a liquid state of aggregation under normal conditions room conditions, i.e. at a temperature of +20–25°C. The vapors of this metal are toxic.
Red mercury is a fictional material. He is credited with incredibly high performance. The existence of such an element is not yet known to the scientific community, since the compound of mercury with high temperature creates mercury sulfide.
Mercury is used in the medical field in the manufacture of thermometers, but these devices are gradually being replaced by safer options. For example, electronic thermometers.
A substance such as mercury is practically irreplaceable in high-precision measuring technology. Its vapors are widely used in fluorescent lamps. Mercury is used in the manufacturing process of certain types of power sources (for example, mercury-zinc batteries).
In the metallurgical industry, mercury is used in the production of various alloys and in the recycling of aluminum. Recently, it has been widely used in jewelry. Mercury is popular in gold production as a means of pre-treating gold-bearing rock to facilitate the separation of the precious metal from the slag.
In the agricultural sector, mercury compounds are part of pesticides, which has an extremely negative impact on the environment. Because of this, this kind of fertilizer is no longer used.
Natural deposits of mineral formations from which mercury is produced in fairly high volumes are called mercury mines. The main mercury ore is cinnabar. The mercury content in it is about 85%. The second most concentrated of this fossil is metacinnabarite.
Mercury is also found in:
Mercury can occur in nature as a native fossil, but such deposits are rare. Mercury can also be simultaneously extracted from oil, cement materials, flux raw materials and coal.
Mercury ores have different morphologies, i.e. deposits can be either plateau-like or contact type, in the form of veins, nests and stockworks. On genetic level may form:
Although the most common are:
It is formed, as a rule, as a result of exposure to low-temperature, low-concentration and hydrothermal solutions.
are less common, but can be formed with the participation of superheated vapor-gas and liquid emanations, with a high content of mercury vapor.
Mercury is extracted in mines with drilling and blasting operations, using electrical equipment and industrial pyrotechnics. The mined red stone is transported from the deposit by conveyor belts, then by truck or train to points for further processing of the ore (concentration plants, processing plants). There, the material is crushed in crushers in one or more stages. Crushed ore is sent to special mills to obtain more fine fraction. For optimal effect, industrial mills are equipped with short bars or balls of steel.
The resulting flour from mercury-containing mineral formations is sent to a tube furnace for heating. Cinnabar, when heated to a certain temperature, interacts with the oxygen contained in the air. This reaction produces sulfur dioxide, which allows the mercury to evaporate. This procedure is called firing.
The rising mercury vapor exits along with water vapor, sulfur dioxide and other combustion products from the furnace and enters a special condenser, where it is cooled. As a result, mercury, which has a boiling point of 357°C, passes into a liquid state. The remaining vapors and gases are released into the atmosphere or used in industrial process to reduce environmental pollution.
Obtaining mercury from ore
The resulting mercury is consolidated. Since this substance has a high specific gravity, all possible additives and impurities will be on the surface in the form of a film or foam. As a result of subsequent filtration, the mercury is purified.
The resulting substance is suitable for use, but not for all applications where mercury is used.
As additional cleaning measures, the liquid metal undergoes mechanical filtration, an electrolytic procedure and purification using chemically active components.
The most popular approach is triple purification. A gradual increase in the temperature of a substance until the impurity separates or the mercury itself evaporates. This procedure is carried out three times to gradually purify the substance.
Nowadays, the leading positions in the world production of mercury ore are occupied by the following countries: 
States former USSR, in which there are large developments of mercury-containing ore - these are Kazakhstan, Ukraine, Tajikistan, Kyrgyzstan, Russian Federation and Uzbekistan.
Most countries that mine mercury do not use it in their own industries. The main consumers of the world's reserves of this liquid metal are the following countries: the United States of America, Japan, Great Britain, France and Germany, since these are large industrial centers.
There is evidence that a mercury leak occurred during a fire in the building of the Scientific Research Institute of Vacuum Technology. At the source of the fire, the concentration of mercury vapor exceeded the maximum permissible concentration, but outside the territory (as well as on the territory itself after work to neutralize mercury) there was no deviation from the standards.
For an objective picture and unambiguous exclusion (or confirmation) of large-scale mercury contamination, it is necessary to carry out not one measurement, but several dozen, and at different times. Without such data, we can only point out that with a truly large release, the concentration of mercury would vary greatly in different areas of the city. And if someone 15 or 20 kilometers from the fire site complains of symptoms of mercury poisoning, then nearby the number of those poisoned clearly must be in the thousands: the population density in the capital in some places exceeds 50 thousand inhabitants per square kilometer.
In other words, rumors of a serious and threatening everyone Residents of the leak seem extremely doubtful. Moscow air is dirty, but it’s unlikely that it’s because of mercury. Moreover, problems with smog began long before the fire: the smell of burning came to the city in the summer, and then the smoke was attributed to peat bogs burning in the Tver region. But since we are talking about mercury, we decided to make a selection of ten statements about the toxicity of this element.
1) Mercury is an extremely dangerous substance. If you accidentally drink a drop of mercury, you can die immediately.
Metallic mercury, contrary to popular belief, is neither a potent poison nor a particularly toxic substance. Suffice it to say that the medical literature describes a case in which a patient swallowed 220 grams of liquid metal and survived. For comparison: the same amount table salt can be fatal (if, of course, someone is able to eat a glass of salt). Detailed guide in the “fatal cases” section, it deals with mercuric chloride poisoning, but does not contain a single mention of fatal poisoning with mercury in the form of pure metal. In addition, mercury has been and continues to be used in the production of dental fillings based on amalgam, an alloy of mercury with other metals. Such fillings are recognized as quite safe and it is not recommended to replace amalgam with other materials unless absolutely necessary.
Pure mercury as a liquid, even if swallowed, is not particularly dangerous. But this cannot be said about metal vapors, much less mercury compounds.
2) Mercury is dangerous because it evaporates and produces toxic fumes.
This is true. Mercury vapor is formed where metal is exposed to open air. They have no smell, no color, and, as a rule, no taste, although sometimes people feel a metallic taste in their mouth. Constantly inhaling polluted air causes mercury to enter the body through the lungs, which is much more dangerous than ingesting the same amount of metal.
3) If a thermometer breaks in an apartment, you must carefully sweep and wash the floor.
This statement is not only incorrect, but also downright harmful. When one drop is divided into two, the specific area and, accordingly, the rate of evaporation of the substance doubles. Therefore, you should not try to brush the mercury with a broom or rag into a dustpan, and then throw it in the trash or flush it down the toilet. In this case, part of the metal will inevitably fly out in the form of tiny balls, which quickly evaporate and pollute the air much more actively than the original drop. And we hope that none of the readers will collect mercury with a vacuum cleaner: it not only crushes the droplets, but also heats them up. If you already have one spilled drop, then simply brush it with a wet brush into a hermetically sealed jar and then hand it over to the DEZ (Direction of the single customer; first it is better to call and find out if they accept it. The recommendation is given for Russia, in other countries the rules may differ) . You can use a piece of paper or, if the drop is small, a small syringe.
American researchers who experimented with mercury in 2008 found that one drop with a diameter of 4 millimeters even in small room a volume of 20 cubic meters after an hour gives only 0.29 micrograms of mercury vapor per cubic meter. This value is within the current standards for air pollution in both the United States and Russia. However, when mercury was smeared with a mop, the concentration of its vapor increased to over one hundred micrograms per cubic meter. That is, ten times higher than the maximum permissible concentration for industrial premises and hundreds of times higher than the “general atmospheric” norm! Wet cleaning, as experiments have shown, after sweeping, mercury no longer helps, and the floor remains contaminated with thousands of small drops after repeated wiping with a wet rag.
4) If a thermometer is broken in an apartment, the room becomes life-threatening for many years.
This is true, but not always. The evaporation of metallic mercury slows down after some time due to the coating of the metal with a film of mercury oxide, so the drops that have rolled into the cracks can lie for years and even decades. In the handbook of criminology Environmental Forensics: Contaminant Specific Guide with reference to several studies, it is said that mercury somewhere under the floor or behind the baseboard eventually ceases to pollute the atmosphere, but only on the condition that its balls are not exposed there mechanical impact. If a mercury ball falls into a gap between the parquet boards, where it is constantly shaking when walking, evaporation will continue until the drop has completely evaporated. A three-millimeter ball, according to physicists in 2003, evaporates in three years.
5) Mercury poisoning manifests itself immediately.
Only true for high mercury concentrations.
Acute poisoning occurs when you inhale air over a period of several hours that contains more than one hundred micrograms per cubic meter. However, serious (requiring hospitalization) consequences occur at even higher concentrations. For serious mercury poisoning, one broken thermometer is not enough.
For chronic mercury poisoning, if we rely on those presented in the already mentioned Toxicological profile for mercury data, a heavy metal concentration of at least more than ten micrograms per cubic meter is required. This is possible if broken thermometer swept away with a broom and did not neutralize the mercury, however, even in this case, it is unlikely that the inhabitants of the room will feel unwell immediately. Mercury in relatively low concentrations does not lead to immediate nausea, weakness and fever, but can, for example, cause impaired coordination of movements and trembling of the limbs. Young children may also develop a rash, but there is no specific set of symptoms by which even a layman could identify chronic mercury poisoning.
6) Mercury is present in fish and seafood.
Is it true. Pure mercury is converted by some bacteria to methylmercury and then moves up the food chain, primarily in marine biosystems. The last phrase means that initially plankton containing methylmercury is eaten by fish, then these fish are eaten by predators (other fish) and each time the concentration of methylmercury in organisms increases due to its ability to accumulate in animal tissues. Research conducted by oceanologists has shown that the amount of mercury when moving from water and substances dissolved in it to plankton increases tens or even hundreds of thousands of times.
The concentration of mercury in tuna meat reaches 0.2 milligrams per kilogram. Mercury contamination of fish has become a serious problem that requires the concerted work of environmentalists and industry representatives around the world. However, for the majority of Russian residents, who generally eat fish quite rarely (18 kilograms per year versus 24 kg in the USA), this source of mercury is not so significant.
7) If you break a fluorescent lamp, it will pollute the room with mercury.
Is it true. In 2004, a group of American scientists had a row of lamps inside plastic barrel, which was immediately closed with a lid. Experience has shown that the fragments slowly release mercury vapor and up to forty percent of the toxic metal contained inside can be released from the remains of the light bulb.
Most compact lamps contain about 5 milligrams of mercury (there are brands with the amount reduced to one milligram). If we take into account that in the first day approximately half of those forty percent are released, which in principle can leave the fragments, then one broken lamp in a room will exceed the “atmospheric” MPC by five to ten times, but will not go beyond the “working-industrial” MPC . The fragments that have been lying around for a week are already practically harmless from the point of view of contamination of the air with mercury vapor, so one broken light bulb cannot cause mercury poisoning.
It's another thing to break several dozen large fluorescent lamps at once. Such actions, as practice shows, lead to acute mercury poisoning.
8) Most city residents are chronically poisoned by mercury.
An extremely dubious statement. The concentration of mercury in the air of cities is indeed higher, but there is no convincing evidence that this leads to any diseases. Eventually, mercury ends up in the atmosphere and water near many volcanoes. There are deposits that have been mined since antiquity; entire deposits have been built near them, and their inhabitants do not suffer from poisoning.
Identify the negative effects of both mercury and other substances (or not substances, but, say, microwave radiation from mobile phones) is quite difficult in low doses. What manifests itself only after many years requires long-term observations. But over the course of twenty or thirty years, people typically develop a variety of illnesses, many of which may have nothing to do with the suspected substance. If you observe several tens of thousands of people, then some of them will in any case develop chronic diseases and even malignant tumors, without any connection with mercury, radiation or any other factor. Even the well-known harm of smoking these days was not immediately identified: only closer to the middle of the last century, doctors were able to unambiguously link smoking with lung cancer.
Representatives of “alternative medicine” often talk about chronic mercury poisoning, but they cannot be considered objective sources. Many of them simultaneously sell one or another “detoxification program,” often promising to cure diseases allegedly caused by mercury, such as cancer or autism. The official position of American doctors is now that the drugs used to remove mercury from the body (so-called chelate compounds) are more likely to harm than help healthy people. At least three cases of fatal poisoning due to attempts to “cleanse the body of mercury” have been described.
9) Mercury is contained in vaccines.
Mercury is a component of thiomersal, a preservative used in some vaccine preparations. One dose of the vaccine usually contains about 50 micrograms of the substance. For comparison: the lethal dose of the same substance (established in experiments on mice) is 45 milligrams (45,000 micrograms) per kilogram of body weight. One serving of fish can contain about the same amount of mercury as a dose of vaccine.
Thiomersal was blamed for the increase in the number of cases of autism, but back in the early 2000s this hypothesis was refuted by analysis of statistical information. In addition, if we assume that it is mercury, then the increase in the number of cases of autism in the last few decades remains unclear. Previously, people came into contact with mercury much more actively.
10) Mercury pollution has been a problem in recent decades.
This is wrong. Mercury is one of the oldest metals known to mankind, as is cinnabar, a sulfide of mercury. Cinnabar was actively used as a red dye (including for the production of cosmetics!), while mercury was used in a number of processes, from applying gilding to making hats. When gilding domes St. Isaac's Cathedral Sixty craftsmen suffered fatal mercury poisoning, and the expression “mad hatter” reflects the symptoms of chronic poisoning when tanning skins for men’s hats. Until the mid-20th century, toxic mercury nitride was used when processing hides. Mercury was also included in many medications, and in dosages incomparable with thiomersal. Calomel, for example, is a mercuric(I) chloride and has been used as an antiseptic along with sublimate, a mercuric(II) chloride.
In recent decades, the use of mercury in medicine has declined sharply due to evidence of the toxicity of this metal. The same calomel can only be found in homeopathic preparations. Or in “traditional” medicine - a number of mercury poisonings have been recorded after consuming Chinese traditional medicine.
Help: Why is mercury poisonous?
Mercury interacts with selenium. Selenium is a trace element that is part of thioredoxin reductase, an enzyme that reduces the protein thioredoxin. Thioredoxin is involved in many vital important processes. In particular, thioredoxin is needed to fight cell-damaging free radicals, in this case it works in conjunction with vitamins C and E. Mercury irreversibly damages thioredoxin reductase, and it ceases to restore thioredoxin. There is little thioredoxin, and as a result, cells cope less well with free radicals.
