Despite a decline in global mercury consumption global demand is less than half of levels , supply from competing sources and low prices, production of mercury from mining is still occurring in a number of countries. Spain, China, Kyrgyzstan and Algeria have dominated this activity in recent years, and several of the mines are state-owned. The table below gives information on recorded global primary production of mercury since It is likely that this production serves robust local demand for mercury, often for artisanal mining of gold — whether legal or illegal.
Such mercury production would require both accessible mercury ores and low-cost labor in order for it to occur despite low-priced mercury available in the global commodity market.
Large quantities of mercury have come onto the market as a result of ongoing substitution and closing of mercury-based chlor-alkali production in Europe and other regions. However, to the extent there remains a legitimate demand for mercury, the re-use and recycling of mercury replaces the mining and smelting of virgin mercury, which would involve additional releases and would result in mobilising new mercury into the market and the environment.
The preference for reuse and recycling of mercury over mining - especially in the context of large mercury inventories coming onto the market? For this reason, certain precautions are being taken, as described below.
Within the current decade and beyond, vast supplies of mercury will become available from conversion or shutdown of chlor-alkali facilities using the mercury process, as many European countries press for a phase-out of this process before From the European Union alone, this may introduce up to 13, metric tons of additional mercury to the market equal to some years of primary mercury production.
While this agreement clearly represents an effort by all parties to responsibly address the problem of surplus mercury, some people have the view that there are not yet adequate controls on where this mercury would be sold or how it would be used. Similarly, large reserve stocks of mercury held by various governments have become superfluous, and are subject to future sales on the world market if approved by the relevant national authorities.
This is the case in the USA, for example, which holds a 4, metric ton inventory of mercury. Mercury can readily combine with chlorine, sulfur, and other elements, and subsequently weather to form inorganic salts. Inorganic mercury salts can be transported in water and occur in soil. Dust containing these salts can enter the air from mining deposits of ores that contain mercury. Emissions of both elemental or inorganic mercury can occur from coal-fired power plants, burning of municipal and medical waste, and from factories that use mercury.
Inorganic mercury can also enter water or soil from the weathering of rocks that contain inorganic mercury salts, and from factories or water treatment facilities that release water contaminated with mercury. Although the use of mercury salts in consumer products, such as medicinal products, have been discontinued, inorganic mercury compounds are still being widely used in skin lightening soaps and creams.
Mercuric chloride is used in photography and as a topical antiseptic and disinfectant, wood preservative, and fungicide. In the past, mercurous chloride was widely used in medicinal products, including laxatives, worming medications, and teething powders. It has since been replaced by safer and more effective agents. Mercuric sulfide is used to color paints and is one of the red coloring agents used in tattoo dyes.
Human exposure to inorganic mercury salts can occur both in occupational and environmental settings. Occupations with higher risk of exposure to mercury and its salts include mining, electrical equipment manufacturing, and chemical and metal processing in which mercury is used. In the general population, exposure to mercuric chloride can occur through the dermal route from the use of soaps and creams or topical antiseptics and disinfectants. Another, less well-documented, source of exposure to inorganic mercury salts among the general population is from their use in ethnic religious, magical, and ritualistic practices and in herbal remedies.
When inorganic mercury salts can become attached to airborne particles. Rain and snow deposit these particles on land. Even after mercury gets deposited on land, it often returns to the atmosphere, as a gas or associated with particles, and then redeposits elsewhere. As it cycles between the atmosphere, land, and water, mercury undergoes a series of complex chemical and physical transformations, many of which are not completely understood. Microscopic organisms can combine mercury with carbon, thus converting it from an inorganic to organic form.
Methylmercury is the most common organic mercury compound found in the environment, and is highly toxic. Learn about how people are most often exposed to methylmercury and about the adverse health effects that exposures to methylmercury can produce. Mercury becomes a problem for the environment when it it is released from rock and ends up in the atmosphere and in water. Mercury has been known since ancient times and was discovered in Huancavelica, Peru, in Some of the world's mercury mines, like the ones in the United States, Mexico, and Italy have been significantly depleted.
Mercury is usually found in cinnabar, corderoite and livingstonite in its harmless, inert form. Soluble mercury, which is toxic, is obtained by subjecting these ores to a reduction process. Mercury is a liquid metal element that has many common uses in industry and medicine. The scientific symbol for mercury is Hg. This comes from the Greek word for the element, hydrargyum, which means watery silver. Mercury is a metal that a liquid at room temperature.
Mercury melts at negative Because mercury expands or contracts evenly when it is subjected to changes in temperature and pressure, it makes an accurate tool for measuring both. It is a frequent ingredient in both thermometers and barometers for this reason. Mercury is so highly reflective that it was once used to float the Fresnel lenses that enhanced the visibility of the lights in lighthouses.
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