Talk:Perfluorooctanoic acid

Where's the carbon?

I've been a software developer all my life and don't have a whole lot of chemistry training, but when something looks wrong or appears that it is wrong, I notice, e.g. I noticed that the Wikimedia Commons SVG image of the Seal of the U.S. Srate of Nevada is missing one star, as opposed to the correct one with 36 stars. So maybe I missed something or my lack of chemical knowledge has made me misunderstand. But I'm curious. The main article shows a 3D molecule image and a molecular chain drawing depicting a string of 15 fluorine atoms, two oxygen atoms, and one hydrogen atom, i.e. F₁₅HO₂, which is fine if correct. But the actual chemical formula is shown as C₈HF₁₅O₂. Okay, fine, the hydrogen goes earlier in the molecular chain. But, as the sating goes, "what's wrong with this picture?" Obviously, given the title, you know my response: Where's the carbon? Neither of these images show any carbon at all. So, either (1) the image is missing some (the catbon) atoms (this was my guess); (2) the formula does not have carbon in it (seems possible since the name isn't carboperfluorooctanoic acid or perfluorocarbooctanoic acid as I would expect); or (3) I'm completely wrong and both are right. I'd like to learn which so that I may understand better.

"Understanding of things by me is only made possible by people — who read my comments — like you."

Thank you.
Paul Robinson (Rfc1394) (talk) 18:54, 1 January 2022 (UTC)

The carbon atoms are not missing in the formula. "Skeletal formulas are the standard notation for more complex organic molecules. In this type of diagram, first used by the organic chemist Friedrich August Kekulé von Stradonitz, the carbon atoms are implied to be located at the vertices (corners) and ends of line segments rather than being indicated with the atomic symbol C. Hydrogen atoms attached to carbon atoms are not indicated: each carbon atom is understood to be associated with enough hydrogen atoms to give the carbon atom four bonds." JimRenge (talk) 20:37, 1 January 2022 (UTC)

Refs 41 and 42 should be replaced

The sentence "as a salt, its dominant use is as an emulsifier for the emulsion polymerization of fluoropolymers such as PTFE, polyvinylidene fluoride, and fluoroelastomers" has two references which are not germane to the use of PFOA as an emulsifier. They should be replaced with references that speak directly to the use in polymerization reactions. (It also makes me wonder how well-referenced the rest of this article is.)

This one is broken:

Sandy, Martha. Petition for Expedited CIC Consideration of Perfluorooctanic Acid (PFOA) (PDF). State of California, Office of Environmental Health Hazard Assessment, Cancer Toxicology and Epidemiology Section, Reproductive and Cancer Hazard Assessment Branch. Retrieved 2008-09-27.

This one is not about the uses of PFOA and provides no references to emulsification or polymerization processes:

Lau C, Anitole K, Hodes C, Lai D, Pfahles-Hutchens A, Seed J (October 2007). "Perfluoroalkyl acids: a review of monitoring and toxicological findings". Toxicol. Sci. 99 (2): 366–94. doi:10.1093/toxsci/kfm128. PMID 17519394. Mccambjd (talk) 03:27, 22 December 2022 (UTC)

Well, it contains the following sentence:

PFOA is used as an emulsifier in the production of polytetrafluoroethylene as well as other fluoropolymers and fluoroelastomers.

--Leyo 19:56, 22 December 2022 (UTC)

Health effects

Just a friendly reminder that if you ever find yourself writing something like "An in vitro study using porcine cells" to talk about health effects, you're probably making a mistake. The goal is to Wikipedia:Manual of Style/Medicine-related articles#Cite sources, don't describe them. WhatamIdoing (talk) 16:42, 8 October 2023 (UTC)

Indeed, WP:MEDSAY ! Bon courage (talk) 16:48, 8 October 2023 (UTC)

Proposed reorg of articles on PFAS

I propose that all articles on Per- and polyfluoroalkyl substances (PFAS) be revised as follows: the PFAS be recognized as the master article in this collection. Most regulatory and health content from the sub-articles (PFOS, etc) would be relocated to PFAS. The subsidiary articles would then be a fairly dry descriptions of the chemical with an emphasis on directing readers to the master article.

What problem am I trying to solve? PFAS needs help. The subsidiary articles need more help. We lack the editors to maintain all of them. So lets simplify most to "non-newsy" content and lets boost the master with all of the topical info.

The plan:

• Per- and polyfluoroalkyl substances 158 kbyte (241 refs) proposed as master for regulatory, health, environmental aspects
  • Perfluoroalkyl carboxylic acids 7.6. proposed to be stripped of most regulatory, health, environmental aspects, with big "main" directing readers to PFAS
    • Perfluoropropionic acid 4.8. proposed to be stripped of most regulatory, health, environmental aspects, with big "main" directing readers to PFAS
    • Perfluorobutanoic acid 5.6. proposed to be stripped of most regulatory, health, environmental aspects, with big "main" directing readers to PFAS
    • Perfluorooctanoic acid 129 190 refs. proposed to be stripped of most regulatory, health, environmental aspects, with big "main" directing readers to PFAS
    • Perfluorononanoic acid 18. proposed to be stripped of most regulatory, health, environmental aspects, with big "main" directing readers to PFAS
      • Ammonium perfluorononanoate 3.5. proposed to be stripped of most regulatory, health, environmental aspects, with big "main" directing readers to PFAS
    • Perfluorodecanoic acid 25. proposed to be stripped of most regulatory, health, environmental aspects, with big "main" directing readers to PFAS
    • FRD-903 5.7 (a branched PFAS). proposed to be stripped of most regulatory, health, environmental aspects, with big "main" directing readers to PFAS

• • Perfluorosulfonic acids 4.6. proposed to be stripped of most regulatory, health, environmental aspects, with big "main" directing readers to PFAS
    • Perfluoropropanesulfonic acid 2. proposed to be stripped of most regulatory, health, environmental aspects, with big "main" directing readers to PFAS
    • Perfluorobutanesulfonic acid 9. proposed to be stripped of most regulatory, health, environmental aspects, with big "main" directing readers to PFAS
      • Nonaflate 1 (perfluorobutanesulfonate). proposed to be stripped of most regulatory, health, environmental aspects, with big "main" directing readers to PFAS
    • Perfluorohexanesulfonic acid 19. proposed to be stripped of most regulatory, health, environmental aspects, with big "main" directing readers to PFAS
    • Perfluorooctanesulfonic acid 54. proposed to be stripped of most regulatory, health, environmental aspects, with big "main" directing readers to PFAS
      • Perfluorooctanesulfonyl fluoride 16. proposed to be stripped of most regulatory, health, environmental aspects, with big "main" directing readers to PFAS
    • Perfluoro(4-ethylcyclohexane)sulfonic acid 3. proposed to be stripped of most regulatory, health, environmental aspects, with big "main" directing readers to PFAS

--Smokefoot (talk) 13:44, 29 July 2024 (UTC)