Talk:Benzalkonium chloride
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Synthesis
[edit]Why no information on laboratory methods for synthesis/analysis? — Preceding unsigned comment added by 2601:193:C400:621:B482:34BF:EEBD:8332 (talk) 13:37, 4 April 2020 (UTC)
Caution
[edit]50ml of a 50% solution in a 4000 litre fishpond killed all goldfish within hours. Some waterlilly leaves are turning yellow but I'm not yet sure if this chemical is the cause.
"The substance is very toxic to aquatic organisms." (67.171.24.88 20:41, 31 March 2007 (UTC))
Aquatic lifeforms are highly susceptible to soaps and detergents, hence the understandable fuss about overuse of laundry detergents. Benzalkonium is a cationic surfactant, and carries clear warnings that aquatic organisms can be harmed by this substance. Benzalkoniumm is widely used in the presence of fish in aquaculture, where it is used to prevents parasitic colonisation of fish and shrimp stocks, and to control algal growth. Most benzalkonium products on the market would have a maximumm strength of 10-15%, which are then diluted 1:200 or more for biocidal use. This is really powerful stuff!! So pouring a 50% solution into a pond was akin to using a cluster bomb to kill a mouse. As with all things, the secret's in the DOSAGE!!
- 50g in about 4000 L of solution? About 12.5 mg/L, which is well above the EPA's LC50 for fish of 280 micrograms per liter. (http://www.epa.gov/oppsrrd1/REDs/adbac_red.pdf). --SV Resolution(Talk) 18:53, 30 March 2009 (UTC)
Redirection
[edit]"Zephiran" redirects here, but that name does not occur in the article even once. —Preceding unsigned comment added by 85.101.1.17 (talk) 18:58, 10 November 2007 (UTC)
Zephiran is a tradename for benzalkonium chloride.[1] It would be improper to include the name Zephiran in the article unless all competing tradenames are also included. However, it is proper to redirect each tradename to the article, otherwise there would be several redundant articles, one for each tradename. Greensburger 21:10, 10 November 2007 (UTC)
"Cetalkonium chloride" also redirects here without the name occurring in the article. Is Cetalkonium chloride also a trade name for benzalkonium chloride? Should these redirections have the template Template:R from alternative name? I found "Cetalkonium chloride" in the Bonjela article, and I searched for it to find out what it is. Coyets (talk) 15:08, 4 May 2009 (UTC)
References
- ^ products.sanofi-aventis.us/zephiran/zephiran.pdf
Pseudoscience and Safety of Benzalkonium Chloride
[edit]Benzalkonium has been in existence for over a century, and is probably the most intensely studied synthetic biocide available to man. Serious scientific studies pre-date the Russian Revolution. Few points briefly:
1. Fertility studies and birth defects need serious controlled multi-generational studies. Am astounded that an animal care technician has managed to get a publication based on an isolated incident (an observation as opposed to a serious controlled study), when there is overwhelming 'scientific' evidence to the contrary. Topically applied benzalkonium does not become systemic at concentrations present in public use disinfectants, even if exposed to the concentrate. To cause the claimed effects, benzalkonium chloride would need to cross the skin barrier and become systemic at concentrations high enough or sustained enougth to cause this sort of damage. Not remotely convincing, even in newborn mice (LOAEL for orally administered benzalkonium is 400 ppm).
2. Allergenicity is all too often confused with skin irritancy effects following frequent exposure. Allergenic capacity is defined by the ability to induce immunological involvement, and recent 6 month studies have shown that this is not inducable with Benzalkonium chloride (Moore, G. 1999) . Unfortunately, there doesn't seem to be an internationally accepted model for allergenicity testing, animal or otherwise.
3. Mucosal effects, on the other hand, could possibly be caused by the membrane disruptive effects of benzalkonium chloride or other any detergent. Its a matter of balancing pharmaceutical benefits with discomfort, and finding alternatives with an equivalent proven history of safety.
- BUT SEE:
- Rizzo JA, Medeiros D, Silva AR, Sarinho E.
- Benzalkonium chloride and nasal mucociliary clearance: a randomized, placebo-controlled, crossover, double-blind trial.
- Am J Rhinol. 2006 May-Jun;20(3):243-7.
- ...
- "CONCLUSION: BKC in the concentration used in nasal preparations impaired mucociliary clearance in healthy individuals after 3 weeks of use. Presently, when preservative-free alternatives are available, BKC could be a risk without benefit." PMID 16871922
Benzalkonium chloride damages, and ultimately kills, cilia -- PubMed citations
[edit]Benzalkonium chloride damages, and ultimately kills, cilia.
Riechelmann H, Deutschle T, Stuhlmiller A, Gronau S, Bürner H.
Nasal toxicity of benzalkonium chloride.
Am J Rhinol. 2004 Sep-Oct;18(5):291-9.
"CONCLUSION: BAC in concentrations used in nasal preparations is ciliotoxic."
"Influence of preservatives and topical steroids on ciliary beat frequency in vitro." PubMed.
"Influence of preservatives and topical steroids on ciliary beat frequency in vitro."
"The preservative benzalkonium chloride effected an irreversible ciliostatic activity already in the concentration of 0.005%." PubMed.
- "Benzalkonium chloride affected the nasal mucosa in the form of ciliary loss, epithelial spongiosis, mucosal swelling, hyperemic subepithelium with increased mononuclears in lamina propria. http://medind.nic.in/jae/t06/i1/jaet06i1p60.pdf http://74.125.47.132/search?q=cache:iRymEiMPd1IJ:medind.nic.in/jae/t06/i1/jaet06i1p60.pdf+Benzalkonium+chloride+cilia&cd=4&hl=en&ct=clnk&gl=us&client=firefox-a
Bernstein IL J Allergy Clin Immunol. 2000 Jan;105(1 Pt 1):39-44. Comment in: J Allergy Clin Immunol. 2000 Sep;106(3):595-6.
Is the use of benzalkonium chloride as a preservative for nasal formulations a safety concern? A cautionary note based on compromised mucociliary transport.
...
- "CONCLUSION: Both animal and human in vitro data suggest that BKC promotes ciliostasis and reduction in mucociliary transport that may be partially masked by absorption and dilution effects occurring in respiratory mucus. These possible confounding factors may account for several disparate human in vivo results. ..." PMID 14726922
Rizzo JA, Medeiros D, Silva AR, Sarinho E.
Benzalkonium chloride and nasal mucociliary clearance: a randomized, placebo-controlled, crossover, double-blind trial.
Am J Rhinol. 2006 May-Jun;20(3):243-7.
...
- "CONCLUSION: BKC in the concentration used in nasal preparations impaired mucociliary clearance in healthy individuals after 3 weeks of use. Presently, when preservative-free alternatives are available, BKC could be a risk without benefit." PMID 16871922
Rizzo JA, Medeiros D, Silva AR, Sarinho E.
Benzalkonium chloride and nasal mucociliary clearance: a randomized, placebo-controlled, crossover, double-blind trial.
Am J Rhinol. 2006 May-Jun;20(3):243-7.
PMID 16871922
Marple B, Roland P, Benninger M.
Safety review of benzalkonium chloride used as a preservative in intranasal solutions: an overview of conflicting data and opinions.
Otolaryngol Head Neck Surg. 2004 Jan;130(1):131-41. Review.
PMID 14726922
Verret DJ, Marple BF.
Effect of topical nasal steroid sprays on nasal mucosa and ciliary function.
Curr Opin Otolaryngol Head Neck Surg. 2005 Feb;13(1):14-8. Review.
PMID 15654209
Graf P.
Benzalkonium chloride as a preservative in nasal solutions: re-examining the data.
Respir Med. 2001 Sep;95(9):728-33. Review.
PMID 11575893
Graf P.
Rhinitis medicamentosa: aspects of pathophysiology and treatment.'
Allergy. 1997;52(40 Suppl):28-34. Review.
PMID 9353558
Graf P.
Rhinitis medicamentosa: a review of causes and treatment.
Treat Respir Med. 2005;4(1):21-9. Review.
PMID 15725047
Chiambaretta F, Pouliquen P, Rigal D.
[Allergy and preservatives. Apropos of 3 cases of allergy to benzalkonium chloride]
J Fr Ophtalmol. 1997;20(1):8-16. Review. French.
PMID 9099278
Armengot M, Basterra J, Garcia-Bartual E. The influence of anesthetics and vasoconstrictors on nasal mucociliary transport. Acta Otorhinolaryngol Belg. 1989;43(2):149-56. Review. PMID 2481378
Illum L.
Nasal clearance in health and disease.
J Aerosol Med. 2006 Spring;19(1):92-9. Review.
PMID 16551220
Ill-health effects of Zicam explained by benzalkonium chloride?
[edit]So perhaps benzalkonium chloride is the explanation for the ill-health effects of Zicam. The following from a search of the Zicam site for "benzalkonium chloride" on June 17, 2009 (when the news of Zicam's ill-health effects came out):
"Extreme Congestion Relief Nasal Gel ... are: Alkoxylated diester, Aloe barbadensis gel, Benzalkonium chloride, Benzyl alcohol, Disodium EDTA, Disodium phosphate, ... http://www.zicam.com/node/247
Intense Sinus Relief Nasal Gel ... are: Alkoxylated diester, Aloe barbadensis gel, Benzalkonium chloride, Benzyl alcohol, Disodium EDTA, Disodium phosphate, ... http://www.zicam.com/node/248
Elsewhere on the web, the ingredients are listed as:
Active Ingredients: Zincum Glucoincum* 2x Inactive Ingredients: Benzalkonium chloride, glycerine, hydroxyethlycellulose, purified water, sodium chloride, and sodium hydroxide.
—Preceding unsigned comment added by 66.167.95.48 (talk) 23:45, 17 June 2009 (UTC)
marketing as treatment for finger nail fungal infections
[edit]This chemical is being marketed as a lotion to treat Fungal infections of finger nails and toe nails. i would like to know if there are any medical reports about its effectiveness and usage.
Ashok Mogre 4th June 2004
what happens if swallowed? —Preceding unsigned comment added by 68.165.11.197 (talk) 00:49, 3 May 2010 (UTC)
Many mass-marketed inhaler and nasal spray formulations contain benzalkonium chloride despite substantial evidence that it interferes with function of the cilia of the respiratory epithelium
[edit]Many mass-marketed inhaler and nasal spray formulations contain benzalkonium chloride despite substantial evidence that it interferes with function of the cilia of the respiratory epithelium
66.167.61.217 (talk) 21:05, 23 May 2010 (UTC)
Commercial
[edit]The first paragraphs read like advertising copy (eg. "As the antiseptic in Bactine, benzalkonium chloride has been used safely for decades on childhood scrapes and cuts.") while the Safety section has serious concerns.
Also, it's an elaborate-tense double negative to say "it has the advantage of not burning when put on a wound, which is not the case with ethanol-based antiseptics or hydrogen peroxide" (just helping here, "an advantage of benzalkonium chloride has not currently been shared by ethanol-based antiseptics or hydrogen peroxide antiseptic which is when burning was not the case without application to unbroken skin by one"). — Preceding unsigned comment added by 24.78.10.84 (talk) 05:50, 8 November 2011 (UTC)
Treatment of HF burns
[edit]An iced solution of benzalkonium chloride can be used to treat hydrofluoric acid burns (see this document). — Preceding unsigned comment added by 93.146.170.178 (talk) 09:20, 23 February 2012 (UTC)
Only for skin burns - http://www.cdc.gov/niosh/ershdb/EmergencyResponseCard_29750030.html WitheredLimb (talk) 09:53, 8 October 2014 (UTC)
Seems calcium gluconate ointment currently best treatment for HF skin burns, not BZK which was noted as being not effective: http://www.ncbi.nlm.nih.gov/pubmed/4067676 WitheredLimb (talk) 22:58, 8 October 2014 (UTC)
2010 review undercuts claims of benzalkonium chloride safety
[edit]Beule AG (Achim G. Beule)
Physiology and pathophysiology of respiratory mucosa of the nose and the paranasal sinuses
GMS Curr Top Otorhinolaryngol Head Neck Surg. 2010; 9: Doc07.
Published online 2011 April 27.
- Abstract
- In this review, anatomy and physiology of the respiratory mucosa of nose and paranasal sinuses are summarized under the aspect of its clinical significance. Basics of endonasal cleaning including mucociliary clearance and nasal reflexes, as well as defence mechanisms are explained. Physiological wound healing, aspects of endonasal topical medical therapy and typical diagnostic procedures to evaluate the respiratory functions are presented. Finally, the pathophysiologies of different subtypes of non-allergic rhinitis are outlined together with treatment recommendations.
...
- Decongestants used to have benzalkonium chloride as a preservative. This quartery ammonium compound is capable of destroying cell walls of microorganisms. In-vitro, toxic effects on cilia [252], deterioration of granulocyte chemotaxis and phagocytosis [256] and of neutrophil defense [257] have been reported. Because benzalkonium chloride aids development of drug-induced rhinitis [253], [258], aggravates its symptoms [241], [259] and may provoke rhinitis medicamentosa if used alone [260], only a few formulations in Europe are still available containing benzalkonium chloride [240].
- Structural changes in rhinitis medicamentosa include damage and loss of cilia [261], metaplasia [261] and epithelial oedema [262], tears in the basal membrane [261] and openings in subepithelial endothel [250], [261] together with vasodilatation [241]. Moreover, hyperplasia of goblet cells [251], [262] and infiltration of inflammatory cells [263] were demonstrated probably as equivalent of reparative changes with increased expression of epithelial growth factor [263]. As complication, septal perforation may occur [264]. If not adequately treated, this disease leads to secondary atrophic rhinitis up to frank clinical picture of ozaena [265].
Author information ► Copyright and License information ▼
Copyright © 2011 Beule
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by-nc-nd/3.0/deed.en). You are free to copy, distribute and transmit the work, provided the original author and source are credited.
+++++++++ --Ocdnctx (talk) 01:29, 4 June 2012 (UTC)
as Viroxyn
[edit]FDA-approved Viroxyn's Active Ingredients are Benzalkonium Chloride 0.13% and Benzocaine 5% (source) and they're available inexpensively (non-RS source). It's most effective against HSV-1 (journal article) - better than Abreva, and Famivir. So perhaps it should be mentioned a bit more prominently? --Psrq (talk) 20:34, 15 November 2012 (UTC)
Soap incompatibility
[edit]This article lists BZK as incompatible with soaps and similar. However, it seems to be included in some soap-like forumations. This article does not have a citation for this claim. The same claim appears elsewhere on the web, but I have not seen it cited. It also appears many of those claims copied the text directly from this article.
If anyone has any information on this, either way, that would be a good addition to the article. (Also, I'd really like an answer myself.) Evand (talk) 15:18, 12 May 2014 (UTC)
BAC is a cationic detergent, soap is usually anionic. Budavari, S. (ed.). The Merck Index - Encyclopedia of Chemicals, Drugs and Biologicals. Rahway, NJ: Merck and Co., Inc., 1989., p. 165 WitheredLimb (talk) 05:36, 16 October 2014 (UTC)
Why even-length alkyl chains?
[edit]Could somebody who understands the chemistry update the article to explain why there's only even-length alkyl chains. Do odd-length chains have some kind of incompatible properties, or are they just harder to synthesize, or ....?
- You're on the right track with "harder to synthesize". In terms of commercial availability, most long alkyl groups used in industrial chemistry are derived from natural fatty acids. Fatty acid biosynthesis involves successively stitching together two-carbon pieces, so most fatty acids have an even number of carbon atoms. Therefore alkyl groups with an even number of carbon atoms are simply more readily available. -- Ed (Edgar181) 22:04, 3 October 2014 (UTC)
Looking for information
[edit]Looking for the relevant information from these texts:
Grant WM, Schuman JS. Toxicology of the eye (4th Edition). Charles C Thomas Publisher Ltd, Springfield, IL, USA, 167 (1993)
Clinical Toxicology of Commercial Products: Acute Poisoning, ed. 3, by Marion N. Gleason, M.Sc., Robert E. Gosselin, M.D., Ph.D., Harold C. Hodge, Ph.D., D.Sc., and Roger P. Smith, Ph.D. Baltimore: The Williams and Wilkins Co., 1969 ISBN 10: 0683036602 / 0-683-03660-2 ISBN 13: 9780683036602 Publisher: Lippincott Williams & Wilkins,US
If you can assist please email me via the link in your page update notification. WitheredLimb (talk) 22:03, 4 November 2014 (UTC)
Request consensus on removal of information relating to adverse health claims of BZK.
[edit]There is currently a discussion on whether the references to adverse health claims should be removed from the BZK page. They were removed with minimal attention approximately 12 hours ago and have since been replaced under headings clarifying their status. These citations have been added in good faith. This is a place to discuss those citations and their relevance to the BZK compound. My justification for inclusion is as follows:
"...Further, re: your removal of pre-clinical studies; you would be aware that the lack of progression from pre-clinical trials is due to the findings of deleterious effects in animal and experimental studies, it is not ethical for these studies to be extended to humans. To include these studies provides a context for the lack of human clinical trials, to exclude them is to withhold information from readers, which is not in line with WP principles. I will re-present the other citations in a way which confirms with WP reliable data guidelines and request that they are only removed following consensus on the BZK Talk page.
I remind you that the benzalkonium chloride page is a page on a chemical compound, not a medical page. BZK has many applications and this page is unlikely to only be searched for those looking for medical information relating to humans only..."
Would appreciate other views. WitheredLimb (talk) 07:52, 28 November 2014 (UTC)
Link to discussion on WikiProject_Medicine page: https://wiki.riteme.site/wiki/Wikipedia_talk:WikiProject_Medicine#Benzalkonium_chloride WitheredLimb (talk) 08:04, 28 November 2014 (UTC)
- Whether the page as a whole is a medical page or not is irrelevant-the specific claims being discussed on this page ARE ones related to health and are therefore subject to WP:MEDRS. Consensus is not required for the initial removal of content like this and edit summaries were provided with justification that these studies appear to fail MEDRS due to their primary nature (many are in-vitro studies, animal studies, epidemiological studies, etc.) and many are quite old (some are even from the 1980s and 1990s). I'm not sure what "removed with minimal attention" means. I wasn't aware that I had to advertise the removal of questionable content and I never implied once that they were added in bad faith so I'm not sure where the defensive bit about good faith is coming from. I agree that additional comments from other editors would be beneficial here. TylerDurden8823 (talk) 08:07, 28 November 2014 (UTC)
I'm not defensive, merely impressed that you could evaluate approximately 50 citations against WP:MEDRS in only 25 minutes. Some of the citations in other sections are from the 1950s. That does not preclude them from being relevant. WitheredLimb (talk) 08:18, 28 November 2014 (UTC)
- Sounded that way to me. In any case, articles being from the 1950s does not necessarily preclude them from inclusion, but it's a very strong strike against them when there is far newer literature reviewing the topic. This also does not address the primary nature of the material (the age was really just icing on top). TylerDurden8823 (talk) 08:23, 28 November 2014 (UTC)
- Hi WitheredLimb, and welcome to Wikipedia. We have some rules about sources for biomedical content that will seem weird to anyone who's published journal articles in the area. We try, as much as possible, to cite only papers published in the last five or ten years, and almost always only review articles, higher-level textbooks, professional reference works, and other similar secondary sources. (I know: if you're writing a journal article, they demand that you cite the original papers, not someone's interpretation of the original papers. But the standards here are very different.)
- Also, as a matter of encyclopedic style, we try to summarize the main points and omit details. For example, this paragraph:
Benzalkonium chloride is effective at exceptionally low concentrations; contact lens solutions typically contain exceptionally low (0.002% to 0.01%) concentrations of benzalkonium chloride for effective preservative action.[17] Swan (1944) found that repeated use of benzalkonium chloride at 10-fold higher concentrations of 1:5000 (0.02%) or stronger can denature corneal protein and cause damage to the eye.[18] Walter (1938) identified that concentrations of less than 0.1% benzalkonium chloride instilled into human eyes produced no adverse sensations, whereas concentrations of 0.1% or greater produced “burning and stinging reactions”.[19] Whitehill (1945) determined that the maximum non-irritating concentration of benzalkonium chloride in rabbit eyes is 0.05%.[20]
- should probably be re-written as no more than this:
Benzalkonium chloride is effective as a preservative at low concentrations. Contact lens solutions are typically 0.002% to 0.01% benzalkonium chloride. Higher concentrations can produce unwanted side effects.
- and with a very different type of source to support it, perhaps a book like these. The patent source (#17 at the moment) in particular is not useful for this statement: a patent tells you what some inventor said that he wanted to do, but it does not tell you what is actually used on the market now. A longer explanation is available at WP:PATENTS. WhatamIdoing (talk) 11:14, 28 November 2014 (UTC)
Thanks WhatamIdoing, I too would like to see the patent reference gone but so far have not had the chutzpah to remove it (I did not reference it, it came with the page!). I do find the standards here very weird, especially as, as you say, I specifically by-passed secondary citations in favour of the primaries. I will review citations over the next week or so and slowly improve, are you able to assist me by reviewing the changes? Thought: can I add the primaries to the Further Reading section? WitheredLimb (talk) 11:28, 28 November 2014 (UTC)
- There are good secondary sources such as [1] [2]
- We are not a collection of every primary source that has every been done. Pubmed is good for that. Doc James (talk · contribs · email) 11:51, 28 November 2014 (UTC)
- WitheredLimb, I thought that might be the case (specifically bypassing secondaries to present the best sources by typical research standards). Wikipedia:Ten Simple Rules for Editing Wikipedia might be useful to you, and there are links at the bottom of WP:Expert retention that might be interesting and/or funny if you want to read about our problems for a while.
- I'll try to look in, but this is a busy weekend for me in real life. WP:There is no deadline, so don't feel rushed on my account, and remember that I can pull your work back out of the page history if someone reverts you before I get to look at it.
- If there is a particularly important primary source, then it could be listed in ==Further reading==. Usually, we just omit them, partly because people usually try to keep that section short (less than ten) and there might be dozens of good primaries. (Sometimes people will copy them to the talk page, if there might be a need to look at them or talk about them later, and that's okay, too.) WhatamIdoing (talk) 03:45, 29 November 2014 (UTC)
All adverse health claims are now supported by secondary sources, as requested, and conform to WP:MEDRS. WitheredLimb (talk) 00:22, 8 December 2014 (UTC)
Assessment comment
[edit]The comment(s) below were originally left at Talk:Benzalkonium chloride/Comments, and are posted here for posterity. Following several discussions in past years, these subpages are now deprecated. The comments may be irrelevant or outdated; if so, please feel free to remove this section.
The article has improved enough that the quality assessment as stub is no longer appropriate.
The low importance comment is inappropriate, as significant health safety issues are presented by consumer formulations containing benzalkonium chloride. Nail infections substantive comment moved to new section among substantive comments. 68.165.11.197 (talk) 00:48, 3 May 2010 (UTC) |
Last edited at 00:48, 3 May 2010 (UTC). Substituted at 09:27, 29 April 2016 (UTC)
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"CH3CH2Cl" listed at Redirects for discussion
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