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 It has since been replaced by safer and more effective agents.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.
These releases can happen naturally. Both volcanoes and forest fires send mercury into the atmosphere. The world's governments can't agree on much. So it is a measure of the concern about the effects of mercury in the environment that 93 nations, including the United States, have so far signed the Minamata treaty, designed to curtail mercury pollution.
That means installing equipment to collect it from the exhaust fumes of power stations, smelters and cement works. It means continuing to phase out of the use of mercury in medicines and equipment.
But most challenging is likely to be breaking the link between mercury and gold. How do you persuade millions of small-scale gold miners to stop using the stuff? One way is to use a device known as a retort, that collects the mercury vapour as it is boiled off. It dramatically reduces how much vapour is released into the atmosphere, and means the miners can re-use the mercury, saving them money.
Or you can substitute other things for mercury, says Chris Davis, who co-ordinates a campaign by the Fairtrade Foundation to support small-scale gold miners. He suggests some pretty unpleasant substances: borax - an aggressive chemical used for industrial cleaning - or, even more hair-raising, cyanide,. Both "become safe with exposure to air after about 24 hours," he says. Adopting one of these alternatives would require investment. And that makes it a tough sell for people who are so poor that they willingly endanger the health of their families in order to scrape a living from gold.
But let's not forget the good news here - the world has come together to beat its mercury habit. And if that's possible, then maybe there is still hope we can deal with some of the even bigger environmental challenges we face. Phosphorus: Looming fertility crisis. Helium: Time to ban party balloons? Aluminium: It just keeps on giving. Fairtrade Foundation.
Over the past decade, the US health care sector has virtually phased out mercury-based medical devices. It is nearly impossible to purchase a mercury thermometer in the USA today. Sweden, the Netherlands, and Denmark have successfully phased out all mercury-based medical devices, including sphygmomanometers. Since the s, Cuba has implemented a national policy of replacing its mercury sphygmomanometers with aneroid devices.
Many cities in the world are moving toward mercury-free health centers. Growing numbers of hospitals in the developing countries are moving toward mercury-free health care. In Argentina, more than 70 hospitals have replaced or are on the path to replacing mercury-free thermometers and blood pressure devices. In Sao Paulo, Brazil, more than hospitals have eliminated mercury-based thermometers and sphygmomanometers. In the Philippines, more than 50 hospitals are moving toward mercury-free health care.
In Mexico, more than 10 hospitals are in the process of replacing, or have already replaced, mercury-based medical devices. Two of the former leading US-based mercury blood pressure device manufacturers, Welch Allyn and Trimline Medical, have ended their production of mercury blood pressure devices.
There are many hospitals in India that are mercury free. The Department of Health and Family Welfare, Government of NCT, Delhi, drafted and circulated a written policy to all the government hospitals, which asks the hospitals to curb the use of mercury equipment.
All government hospitals in Delhi have stopped purchase of mercury equipment and are in the process of phasing it out. A nonmercury product replaces any broken mercury instrument. Some of the private hospitals in Delhi had started mercury phaseout as early as when mercury was included in the training programs conducted for medical waste management. The WHO is following these strategic steps for an eventually mercury-free health care:. Short term: Develop and implement plans to reduce the use of mercury equipment and replace it with mercury-free alternatives.
It addresses clean-up, storage, and disposal of mercury. Medium term: Increase efforts to reduce the use of unnecessary mercury equipment in hospitals.
Hospitals should have an inventory of their use of mercury. This inventory should be categorized into immediately replaceable and gradually replaceable.
Long term: Support a ban of mercury-containing devices and promote alternatives. Support countries in developing a national guidance manual for sound management of health care mercury waste. Support countries in the development and implementation of a national plan, policies, and legislation on mercury health care waste.
Support the allocation of human and financial resources to ensure procurement of mercury-free alternatives and a sound management of health care waste containing mercury. Source of Support: Nil. Conflict of Interest: None declared. National Center for Biotechnology Information , U. Indian J Occup Environ Med.
Neeti Rustagi and Ritesh Singh. Author information Copyright and License information Disclaimer. For correspondence: Dr. E-mail: moc. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
This article has been cited by other articles in PMC. Abstract Mercury is toxic heavy metal. Keywords: Mercury, mercury toxicity, occupational hazard. The WHO is following these strategic steps for an eventually mercury-free health care: Short term: Develop and implement plans to reduce the use of mercury equipment and replace it with mercury-free alternatives. Senese F. Why is mercury a liquid at STP? Hammond CR. Cleveland, Ohio: CRC press; Elements, in Handbook of Chemistry and Physics.
World Mineral Production British Geological Survey. National Research Council. Toxicological effects of methylmercury.
S: National Academies Press; Board on Environmental Studies and Toxicology.
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