Talk:Zinc
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Article changed over to new Wikipedia:WikiProject Elements format by Dwmyers 15:29 Feb 19, 2003 (UTC). Elementbox converted 15:21, 2 July 2005 by Femto (previous revision was that of 00:09, 2 July 2005).
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[edit] Information Sources
Some of the text in this entry was rewritten from Los Alamos National Laboratory - Zinc. Additional text was taken directly from USGS Zn Statistics and Information, from the Elements database 20001107 (via [http://www.dict.org dict.org), Webster's Revised Unabridged Dictionary (1913) (via dict.org) and WordNet (r) 1.7 (via dict.org). Data for the table was obtained from the sources listed on the subject page and Wikipedia:WikiProject Elements but was reformatted and converted into SI units.
As for the sex addiction connection to zinc in males see http://www.tiscali.co.uk/lifestyle/healthfitness/menshealth/part1_4-2.html
[edit] Word origin
As to the origin of the word, from the Oxford Dictionary of English, 2nd ed.:
- ORIGIN mid 17th cent.: from German Zink, of unknown origin.
The article currently claims it's possibly from Old Persion. Anyone have any basis for this claim? eaolson 18:53, 6 January 2006 (UTC)
[edit] Talk
Is any reason why in the table-image is 30P 35N (Zn-65) instead of 30p 34N (Zn-64 the most abundant estable isotope? Guillermo 14:52, 4 Jun 2004 (UTC)
[edit] Löhneyes
I removed this line from the article:
- The word "zink", as a term, was originally used by Löhneyes in 1697.
as it is unclear and possibly wrong. There are older uses of the word zinc (e.g. here [1], and the OED has zinke from 1651).
[edit] Properties
[edit] Vapor Pressure
Per the CRC Handbook of Chemistry and Physics, log(p/Pa)=5.006+A+B/T. For solid Zn, A = 6.102 and B = -6776; for liquid Zn, A = 5.378 and B = -6286. From this, I get p = 21.4 Pa for solid Zn. Not sure where the 192.2 value came from. Eric 18:09, 23 Jun 2005 (UTC)
[edit] Removed edits
I've removed some edits made by 63.164.145.85 because they are of dubious accuracy and completely unreference and unsupported.
On the other hand, it has been known for decades that when the free zinc ion concentration in water reaches levels of 100 nanomolar to 1 micromolar, all of the biota are killed, including the vertebrate fish. This has led marine biologists to develop what are known as the "free metal" models of zinc toxicity. Free zinc in the body is also toxic. As little as 10 micromolar in fluids will harm and kill cells.
See [2], which says zinc doesn't become toxic to the animal studied until into the millimolar range.
The presence of zinc in ejaculate is the basis for crime-scene tests for ejaculate, which are merely tests for the high zinc concentration. No one knows why there is elevated zinc in ejaculate, though it has been proposed that the antimicrobial action of zinc ions might be useful for slowing infection in the reproductive system of the male and the female.
According to this [3], the test is for acid phosphatase, not zinc.
The purpose for zinc in semen appears to be complex and not as straighforward as being antimicrobial. This page [4] lists three things zinc in semen does.
- ACTUALLY, THERE IS NO EVIDENCE WHATSOEVER FOR ANY ROLE OF ZINC ION SEMEN, BUT THE ANTIMICRIBIAL HYPOTHESIS IS AT LEST PLAUSIBLE. —The preceding unsigned comment was added by 69.151.205.181 (talk • contribs) 09:32, February 15, 2006.
Swallowing a new (zinc) American penny often leads to lesion in the stomach wall, where the stomach acid brings so much zinc ion into solution that it chemically burns the tissue.
I can't find any support for this in a Google search. There was one case of a schizophrenic patient dying after ingesting dozens of coins, but not zinc lesions.
This has been shown for the virus that causes the common cold, the duration of which is reliably shortened by application of millimolar concentrations of zinc ion into the mouth.
This is by far from certain. From [5], " The effect of zinc treatments on the severity or duration of cold symptoms is controversial... Additional research is needed to determine whether zinc compounds have any effect on the common cold.
- Good move, I was thinking of removing those bits, but hadn't done the research yet to back up a revert. You've done some research, why not add your info to the article?
- Added note: dissolve the zinc out of a new penny with HCl and you get zinc chloride plus about 0.87 litre of hydrogen gas. What the effects of that are in the stomach ... I don't know, and am not curious enough to try it :-) Vsmith 01:53, 27 November 2005 (UTC)
Hi there zincophiles: I have put back essentially all of my input that was previously removed because and added references to guide other readers/editors in evaluating the ionformation. Thus, I have added back the fact that free zinc ions are lethal above a few hundred nanomolar to a few micromolar, and added a recent reference. Those interested in more information should go to MedLine (entrez pubmed) and look up "free metal zinc toxin" or similar. You will find that the marine biologists and agronomists have studied for decades how just a few micromolar of free zinc (i.e., Zn2+ in aqueous solution) is letal to everything, inculding vertebrate fish. Those who put 100's of micromolar or even milliomolar of zinc into solutions do not realize that most of the zinc either precipitates as hydroxides or is bound to (many) organic zinc binders. (For more refs see, e.g., Frederickson et al., Nature Reviews in Neuroscience, 2006)
I also put back the information about zinc tests for finding semen at the crime scene, with a reference.
Another issue that we need to confront is the lack of a heading on ""Medicinal uses of zinc salt." This is because zinc ions (free ions) are potent antimicrobials, and they have been shopwn eeffectsive against the common cold (see most recent review in MedLine). Zinc ions are one of the oldest know effecdtive antimicriobials, in fact. More on this later.
The AREDS study on zinc and macular degeneration claims that zinc in the diet helps slow AMD, but the effect is trivially small. I am doing some research on zinc in the retina, and NONE of the opthalmologists I know presecribe zinc for AMD. This is because (i) too much zinc intake blocks copper utilization, (ii) zinc may CONTRIBUTTE to AMD and (iii) the putative therapeutic effect is so small that it would not even justify the cost of the pills. —The preceding unsigned comment was added by Zincdoc (talk • contribs) 08:32, February 15, 2006 UTC.
[edit] Zinc in semen
I've removed again the language about the forensic tests testing for zinc. I don't think that a zinc test is what's actually used in practice in forensic testing. The given reference was an evaluation of using a zinc test alongside the "gold standard" of acid phosphatase, and concludes that zinc tesing alongside AP will give better results, but it doesn't say if that's what's currently used by forensic-type people. The little that I can find through Google (among the many paternity testing and infidelity testing services, oy) is that the standard forensic crime scene test is an AP test. If anyone can find a authoritative citation online, please list it. eaolson 23:54, 3 May 2006 (UTC)
OK I give on the forensic testing (for now :-))). However, I also removed the sentence about zinc concentration in the prostat bring the highest in the body. This is completely misleading because the zinc is not in the prostate tissue, it is in the prostatic fluid. This can be seen in the micrographs published by Danscher and colleages. Immediately after ejaculation, the prostate tissue per se is most probnably about like other soft tissue, i.e., around 70 - 120 ppm zinc dry weight. The zinc in the prostatic fluid, however, is 10 mM OR MORE !
[edit] Psoriasis
I've also removed the section on psoriasis. It was completely unsourced and flat out wrong in some cases. Calamine is zinc-oxide based, which mean it's probably going to be completely un-ionized, as far as I know. Again, citations and verifiability would be helpful. eaolson 02:28, 4 May 2006 (UTC)
[edit] Toxicity
Should it be indicated that in most practical considerations, zinc is considered nontoxic to humans (as per the Handbook on Toxicity of Inorganic Compounds)?Murphyr 21:46, 20 December 2005 (UTC)
[edit] "wasting of body tissues"
Under the deficiency part. What does that mean?
[edit] mossy zinc
There should be some mention of mossy zinc - I expect several people are looking it up. (It used to be common, now it is hardly mentioned.)
[edit] how is zinc obtained?
The article states nowhere whether zinc is mined or just falls from the sky, before it reaches a smelter. I presume there has to be some sort of mining activity. Why not say so? --dunnhaupt 19:33, 9 November 2006 (UTC)
