Mercury Pollution and the Mercury Geochemical Cycle
Wednesday, 14. January 2009, 19:05:23
Of the geochemical cycles I mentioned here the mercury cycle is the one with the smallest fluxes (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). Nevertheless it is well worth watching carefully because of the toxicity of mercury. All mercury spills are potentially very dangerous.
Mercury (Hg), also known as quicksilver, is the only metal that is liquid at normal temperatures. The production of mercury has luckily declined since the early 1970s. This is partly due to increased recycling and partly to the concern about environmental pollution. Mercury is used in thermometers, barometers, manometers, sphygmomanometers, float valves, and other scientific apparatus, but concerns about the toxicity have led to mercury thermometers and sphygmomanometers being largely phased out in favour of alcohol-filled, digital, or thermistor-based instruments.
Small-scale gold mining is the second-worst source of mercury pollution in the world, after the burning of fossil fuels. Gold can be extracted by amalgamation. The principle of amalgamation is to extract gold from the pulverized ore by mercury. The ore dust is rubbed with mercury which amalgamates with the gold. The amalgam thus produced is an alloy of mercury and gold. Gold is then separated from the mercury either by filtering it through leather or by distillation. The process is forbidden in most countries, but ...
Mercury exists in two different forms, organic and inorganic. In water the most prevalent form of mercury is the organic form. Most fish have trace amounts of mercury. The level of mercury found in a fish is related to the level of mercury in its environment and its place in the food chain. Mercury tends to accumulate in the food chain, so large predatory fish species tend to have higher levels than non-predatory fish or species at lower levels in the food chain. Eating fish contaminated with mercury can cause serious health problems, especially for children and pregnant women, so the general advice in some parts of the world is not to eat fish every day.
Natural sources such as volcanoes are responsible for approximately half of atmospheric mercury emissions.
The human-generated half can be divided into the following estimated percentages:
* 65% from combustion, of which coal-fired power plants are the largest source
* 11% from gold production.
* (34% a lot of other different sources).
As I said mercury pollution has already spurred public health officials to advise eating less fish, but it could become a more pressing concern in a warmer world according to a paper that appears in a recent issue of the journal Oecologia.
Carbon dioxide, the main greenhouse gas, has increased nearly 40 percent since the industrial revolution and is expected to continue climbing unless power plant and other emissions are restricted or curtailed. Carbon dioxide-enriched soil may contain much more mercury, because such soil has greater capacity to trap and hold on to mercury.
While I was writing the first paragraphs of this post, Andrew Alden published an interesting post on mercury (12 January 2009) titled And Now, Conflict Mercury at geology.about.com.
• http://www.sciencedaily.com/releases/2009/01/090107134635.htm
• http://geology.about.com/b/2009/01/12/and-now-conflict-mercury.htm
• http://www.msnbc.msn.com/id/28596948/
• http://geology.about.com/od/mercury/a/Hgmercury.htm
PS of 15 January 2009:
The Swedish Government has forbidden all use of mercury - also in dental fillings - as from 1 June 2009.
Mercury (Hg), also known as quicksilver, is the only metal that is liquid at normal temperatures. The production of mercury has luckily declined since the early 1970s. This is partly due to increased recycling and partly to the concern about environmental pollution. Mercury is used in thermometers, barometers, manometers, sphygmomanometers, float valves, and other scientific apparatus, but concerns about the toxicity have led to mercury thermometers and sphygmomanometers being largely phased out in favour of alcohol-filled, digital, or thermistor-based instruments.
Small-scale gold mining is the second-worst source of mercury pollution in the world, after the burning of fossil fuels. Gold can be extracted by amalgamation. The principle of amalgamation is to extract gold from the pulverized ore by mercury. The ore dust is rubbed with mercury which amalgamates with the gold. The amalgam thus produced is an alloy of mercury and gold. Gold is then separated from the mercury either by filtering it through leather or by distillation. The process is forbidden in most countries, but ...
Mercury exists in two different forms, organic and inorganic. In water the most prevalent form of mercury is the organic form. Most fish have trace amounts of mercury. The level of mercury found in a fish is related to the level of mercury in its environment and its place in the food chain. Mercury tends to accumulate in the food chain, so large predatory fish species tend to have higher levels than non-predatory fish or species at lower levels in the food chain. Eating fish contaminated with mercury can cause serious health problems, especially for children and pregnant women, so the general advice in some parts of the world is not to eat fish every day.
Natural sources such as volcanoes are responsible for approximately half of atmospheric mercury emissions.
The human-generated half can be divided into the following estimated percentages:
* 65% from combustion, of which coal-fired power plants are the largest source
* 11% from gold production.
* (34% a lot of other different sources).
As I said mercury pollution has already spurred public health officials to advise eating less fish, but it could become a more pressing concern in a warmer world according to a paper that appears in a recent issue of the journal Oecologia.
Carbon dioxide, the main greenhouse gas, has increased nearly 40 percent since the industrial revolution and is expected to continue climbing unless power plant and other emissions are restricted or curtailed. Carbon dioxide-enriched soil may contain much more mercury, because such soil has greater capacity to trap and hold on to mercury.
While I was writing the first paragraphs of this post, Andrew Alden published an interesting post on mercury (12 January 2009) titled And Now, Conflict Mercury at geology.about.com.
• http://www.sciencedaily.com/releases/2009/01/090107134635.htm
• http://geology.about.com/b/2009/01/12/and-now-conflict-mercury.htm
• http://www.msnbc.msn.com/id/28596948/
• http://geology.about.com/od/mercury/a/Hgmercury.htm
PS of 15 January 2009:
The Swedish Government has forbidden all use of mercury - also in dental fillings - as from 1 June 2009.
WIDGETIZE
dortejakobsen # 14. January 2009, 20:25
- wonder whether you have any comments to that?
nielsol # 14. January 2009, 21:16
Here is a nasty link
http://www.holisticmed.com/dental/amalgam/
Personally I am extremely worried about the Alzheimer's Disease Connection - not good for the quality of my posts!
Dental amalgam is an alloy of a number of metals, mainly silver, tin and mercury. Medical research organisations say that there is no scientific evidence that the tiny amounts of mercury released from dental fillings are a danger to health, apart from those rare cases where some individuals are unusually sensitive to this material. A number of studies indicate there is no increased health risk or shortening of life between groups of people with amalgam fillings and those with none. Modern dentistry has, however, largely eliminated amalgam as the treatment of choice for new fillings - you never know!
An important point is that amalgam fillings normally only release mercury vapour when they are placed in the teeth or removed, so removing old amalgam fillings does not sound like the right option - take them with you into your grave
dortejakobsen # 15. January 2009, 15:16
Når jeg reagerede, er det netop pga alle de dystre artikler man kan finde på nettet, som advarer om kviksølv i amalgamfyldninger, samt som konserveringsmiddel i vacciner (blev forbudt at bruge kviksølv i denne forb. omkrig 1992, tror jeg, men i hvert fald efter vores grundige vaccinationsprogram før Ethiopien), og den forbindelse, mange ser mellem kviksølv & diabetes, kronisk træthed, autisme og depression: fire diagnoser som findes i det lille hjem her!
Det danske sundhedsvæsen hævder fortsat, at kviksølv i tænderne bliver hvor det skal, men alle (patienter) ved jo, at skidtet revner, falder ud eller bare bliver slidt med årene. Det er også klart, at nogle mennesker (bl.a. min mor) dårligt tåler visse metaller, så det skulle da næsten være underligt, om der ikke også findes mennesker som ikke kan tåle den mindste smule kviksølv i kroppen.
Kh Dorte.
nielsol # 15. January 2009, 15:58
Og der er det ved de sjældne tilfælde, at hvemsomhelst af os kan være et sjældent tilfælde.
nielsol # 15. January 2009, 16:13
Kviksølv fra to millioner danske elsparepærer går hvert år op i røg:
http://ing.dk/artikel/94918
nielsol # 16. January 2009, 12:30
I fremtiden må de svenske tandlæger finde et andet materiale end kviksølv til at fylde hullerne i svenskernes tænder. Den svenske regering har nemlig forbudt al brug af kviksølv.
http://ing.dk/artikel/94920
Reglerne træder i kraft 1. juni 2009
dortejakobsen # 20. January 2009, 11:28
I Danmark er det stadig sådan, at det offentlige giver støtte til kviksølv-fyldninger, men ikke plastik, fordi de ikke er sikre på, plastmaterialerne holder lige så længe!