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Natural Fluorine Does Exist ... In Smelly Rocks
scibri writes "Chemists have proved that a smelly rock is the only known place on Earth where fluorine exists in its elemental form, F2 (Abstract).
The rock is antozonite, a calcium fluoride (fluorite) mineral that is dark violet or even black in colour, also known as fetid fluorite or stinkspar. Needless to say, this rock stinks. The pungent smell is given off when antozonite is crushed, and chemists and mineralogists have argued over the origin of the stench since the early nineteenth century.
It turns out French chemist Henri Moissan, who first isolated fluorine in 1886, was right. The rock contains pockets of fluorine that are released on crushing."
Clues from previous experiments suggested how fluorine might be formed in the rocks. The experiments exposed artificial calcium fluoride to - and -radiation, and high-energy electron beams. The samples often turned violet, because the radiation was splitting calcium fluoride apart to form clusters of calcium ions. Subsequent tests showed that bubbles of fluorine gas were also forming in the lenses.
The same process could explain the stench of antozonite, says Kraus. The mineral contains tiny amounts of radioactive uranium-238, which decays into -emitting daughter nuclides. The rocks have been lying around for 100 million years, says Kraus, which is enough time for the radioactive decay to produce the same effect as seen in the artificial fluorite experiments.
Interesting stuff to a rock nerd.
-AI
For me, it is far better to grasp the Universe as it really is than to persist in delusion
Do you realize that fluoridation is the most monstrously conceived and dangerous Communist plot we have ever had to face?
that's just the way a hardcore commie works
http://www.youtube.com/watch?v=Qr2bSL5VQgM
intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
Sorry, I don't understand. Are we talking about flourine or flouride? I'm 54 (and no chemist so I don't know the difference, please excuse me) and the water I grew up with was flouridated, the toothpaste I use also contains one of the above. To the poster below regarding black teeth. I still have all my teeth and they are not black. Daily brushing and flossing seem to have kept them in pretty good shape over the years.
So..... instead of assuming that everyone knows the dangers, please educate me. That's an honest request actually. I'm no fan of the things the government has done that have been proven to be of harm to the general citizenship, and I believe many such a thing has probably happened. But please, more info. If I need a few more layers on the tinfoil hat I'd like to know :)
Not a chemist either, just a chemistry nerd, but:
First. Its "Fluorine", not "flourine". No ground up wheat is involved. :D (sorry for the nitpick. Its an honest mistake.)
Second, "fluorine" is the elementary pure form. Pure fluorine is a covelently bound pair of fluorine atoms, much like pure oxygen is.
Fluoride is a salt made with fluorine that does not contain oxygen. Eg, "sodium fluoride": a sodium atom ionically attracted to a fluorine atom.
When oxygen is involved, you get "fluorite", and "fluorate", depending on the number of oxygen atoms involved.
Natural fluorites and fluorides occur in groundwater in far higher concentrations than are medicinally useful. Typically, the concentration of fluoride ion required to help stabilize the calcium phosphate complex found in teeth against acid breakdown is less than 1% in solution. (Toothpastes are usually sufficient to get the primary benefit of topical fluoride use, and usually contain .2% fluoride ion in the form of sodium fluoride by weight. Fluoridated water is higher, because the time the water is in contact with teeth while drinking is considerably shorter.) You can have way higher than this in naturally fluoride contaminated water supplies.
High levels of fluoride in drinking water causes abnormal tooth and bone formation, in a condition known as fluorisis. It causes discolored, and fragile teeth, as well as brittle bones that are especially prone to osteoporosis and other bone disorders. As such, the danger of overfluoridation is indeed quite real. However, you would have to regularly eat your toothpaste to have this condition. It is argued that children, the primary reported benefactors to fluoridated water operations, are notoriously bad at proper use of brushing and toothpaste use, and are at significantly higher risk of ingesting the toothpaste instead of spitting it out. In conjunction with fluoridated water, this results in a higher risk of permanent tooth deformities in adult tooth formation from the excess fluoride.
In areas with already dangerous levels of fluoride present in the drinking water from natural sources, the use of a filter to remove the excessive ion concentration is not only beneficial, but highly recommended, as it can indeed cause severe and debilitating tooth and bone problems.
The more you know!
When oxygen is involved, you get "fluorite", and "fluorate", depending on the number of oxygen atoms involved.
One small nit, from another non-chemist chemistry nerd: this never happens. It does with other halogens (bromine, chlorine, iodine), because they can all be oxidized, and in fact combined with oxygen, to make stable oxyhalide anions. Fluorine don't play that; forced into company with oxygen, fluorine does the oxidizing, and oxygen gives up an electron or two. The resulting oxygen difluoride isn't an acid anhydride; mixed with water, it gradually decomposes into hydrofluoric acid and oxygen, instead of making "hypofluorous acid" or whatever.
I'm stunned that you can find free fluorine, in quantities large enough to smell, occurring naturally on the Earth's surface. I'll have to find out more about this. Wonder if anybody's gotten poisoned from it...?
an exact ratio is a poor measure for what is an appropriate fluoride ion intake on a per-person basis.
Different people absorb the ion at different rates upon ingestion, so while one person might develop fluorosis, another might not, despite having an identical diet, and an identical fluoride intake, even when measured in total milligram quantities.
This is part of why fluoridation of drinking water is often a hotbutton issue, even among health experts and chemists. On one hand, there is a clear health benefit for the impoverished, who are statistically less educated, and often have poorer oral hygiene regimens. For such persons and their children, oral fluorine solution in the drinking water may well be the only source of fluorine that they come into contact with, and may make up the major public health contribution against dental caries for those demographics.
It however, has a nastier side.
Fluoride ion is delivered as a salt, dissolved in the water. This salt concentration can be... Concentrated.. by such mundane activities as preparing a meal that makes use of tapwater, such as cooking pasta. As such, the dietary intake of fluoride ion delivered through the municipal water supply may inadvertantly hyper-fluoridate the population, despite being delivered at a low concentration. This is entirely before toothpastes and mouthwashes even enter the picture.
In other countries besides the US, the fluoride is added to milk products, or to salt, in an effort to combat this secondary exposure route that concentrates the ion prior to ingestion, but still have it readily applied to the lower income demographics of the society that would benefit most from the fluoridation.
Sadly, fluorosis does not present itself with a major identifiable diagnostic factor until AFTER it is too late. It simply is incorporated asymptotically into tooth and bone tissues as they develop, and if the concentrations in those tissues are too high, it manifests the disorder.
This incorporation into tooth structure prior to the eruption of primary teeth is known as the "Secondary" benefit of fluoride, and can only be obtained through ingestion, which is often hailed by fluoride promoters. Within certain tolerances, (which are dangerously close to the fluorosis inducing side of things) the incorporation of fluoride into the calcium phosphate complex that comprises tooth enamel makes it naturally harder and more resistant to abrasions and decay. A little fluoride is a good thing.
However, too much fluoride is a bad thing, ranging from "Merely cosmetic", to "pathalogical".
Many people have very mild to moderate tooth fluorosis and do not even know it. It causes white streaking and a pearlescent quality to tooth enamel in the mild to moderate case. Extreme fluorosis causes yellowed, mottled, deformed, and brittle teeth. In most cases, this mild fluorosis is benign, and is merely cosmetic. Your dentist wont even mention it.
If you are worried about your fluoride intake, I really dont know what to tell you, other than to suggest using bottled water instead of municipal tap water to prepare meals, if your water is fluoridated, and to avoid eating your toothpaste, and drinking fluoride containing mouthwashes.
*shrug*
Not a chemist either, just a chemistry nerd, but:
First. Its "Fluorine", not "flourine".
It's "it's" not "its" for 'it is,' or is it?
...Sorry, I'd never correct something like that, but the urge to nitpick a nitpick is just too great. My apologies to all normal people. :)
And all our yesterdays have lighted fools The way to dusty death. --Will