# Talk:Bisphenol A

This article was the subject of a Wiki Education Foundation-supported course assignment, between 23 September 2019 and 13 December 2019. Further details are available on the course page. Student editor(s): Hbhat3, Lexjennifer, Amunoz18, Ebang21, Lucy H Ahn. Peer reviewers: Ghuynh, Chang2021, Jsodhi1.
Above undated message substituted from Template:Dashboard.wikiedu.org assignment by PrimeBOT (talk) 15:51, 16 January 2022 (UTC)

Hi, there was a request made by @Project Osprey: to identify sources that potentially do not meet WP:MEDRS. I have not reviewed all of the sources, but from what I can see most look like review articles. Here are a few that may be primary research studies. I have not reviewed where these occur in the text, for example to see if they are appropriate or not. 

Ref # 30- https://pubmed.ncbi.nlm.nih.gov/19627357 - A primary source but with over 200 citations. I can't find a good secondary ref but I've added some additional refs ones showing that it's common in dental cements.
Ref #32 also may be a primary study from 1985 https://doi.org/10.1002%2Fpol.1985.170230616 - I'm having difficulty here. @Smokefoot: can you verify if this this secondary source supports synthesis being from BPA? doi:10.1002/14356007.a21_449.pub4 (sorry for the ping)
Ref 45 https://www.jstage.jst.go.jp/article/jec1991/14/1/14_1_57/_article - Primary but supporting a primary measurement (that's allowed isn't it?)
Ref 66 is a news article about a study and would not meet https://news.ncsu.edu/2012/09/wms-patisaul-amygdala/ - Removed
Ref # 67 https://doi.org/10.1093%2Fjb%2Fmvm158 x-ray crystallography study  - More of a binding study really. I'm not sure.
Ref #73 https://doi.org/10.5194%2Fdwes-9-27-2016 - Removed
I hope that this helps a little! Congrats on all the hard work on this article!
JenOttawa (talk) 12:37, 31 March 2022 (UTC)

This review is transcluded from Talk:Bisphenol A/GA1. The edit link for this section can be used to add comments to the review.
Reviewer: Bli231957 (talk · contribs) 19:20, 20 June 2022 (UTC)

GA review (see here for what the criteria are, and here for what they are not)
It is reasonably well written: 
a (prose, spelling, and grammar): 
b (MoS for lead, layout, word choice, fiction, and lists): 

It is factually accurate and verifiable: 
a (reference section): 
b (citations to reliable sources): 
c (OR): 
d (copyvio and plagiarism): 

It is broad in its coverage: 
a (major aspects): 
b (focused): 

It follows the neutral point of view policy: 
Fair representation without bias: 

It is stable: 
No edit wars, etc.: 

It is illustrated by images and other media, where possible and appropriate: 
a (images are tagged and non-free content have non-free use rationales): 
b (appropriate use with suitable captions): 

Overall:
Pass/Fail: 

Hello there, I will be reviewing this article. Note that I won't come Wikipedia very often, so I might take a while to respond. Bli231957 (talk) 19:28, 20 June 2022 (UTC)

That's ok, any improvements might take a while to push through anyhow. Thanks for accepting the job! Editors at WP:Chem might also be able to provide some input. --Project Osprey (talk) 09:38, 21 June 2022 (UTC)
This page gets quite a lot of pageviews, so I might be quite strict. Bli231957 (talk) 19:33, 21 June 2022 (UTC)
I'll do this GA review quite quickly, so it'll hopefully finish before July. Bli231957 (talk) 15:45, 24 June 2022 (UTC)
Sorry for the delay, but I might not come back on this for a while. By the way I changed my username from Bli231957. Praseodymium-141 (talk) 20:15, 13 July 2022 (UTC)
Not to worry. I've also become derailed by real life, and probably wont be able to finish the next round of edits until next week. I'm still going to try and finish this process; I feel like it's close to the end. Project Osprey (talk) 20:39, 13 July 2022 (UTC)
Yeah, I've also become derailed by real life. No worries! Praseodymium-141 (talk) 10:43, 15 July 2022 (UTC)


### Comments
Reliable sources:

Is https://www.foodstandards.gov.au/consumer/chemicals/bpa/Pages/default.aspx (cite 60) a reliable source?
Yes. It's the website for the relevant Australian statutory authority. I have modified the ref to try and clarify this.
Is https://laws-lois.justice.gc.ca/eng/acts/C-1.68/index.html (cite 63) a reliable source?
Yes. It's the website for the relevant Canadian statutory authority. I have modified the ref to try and clarify this.
Is https://news.ncsu.edu/2012/09/wms-patisaul-amygdala/ (cite 66) a reliable source (it is a news article)?
Ref 66 points to a different site (https://www.ehn.org/bisphenol-a-2639174350.html), I can't seem to find the link to the URL you provide. Regardless ref 66 is weak and I've deleted it. The statement is still referenced by a direct link to ECHA
Maybe check here for some sources that might not meet WP:MEDRS. Bli231957 (talk) 20:17, 21 June 2022 (UTC)
Others: 

In the "History" section, what does this sentence mean: "He found BPA to be 1 / 37,000 as effective as estradiol"? Bli231957 (talk) 20:09, 21 June 2022 (UTC)
I've reworked this, the statement did not appear to be supported by the refs given. Somewhat predictably, there are a range of reported binding affinities. General range is about right though.
In the "Production" section, how does "para selective" have to do with "Arene substitution pattern"? Bli231957 (talk) 20:09, 21 June 2022 (UTC)
I had though that straightforward but I have tried to clarify.
The section "Toxicity" is too short. Maybe expand it or merge it with the main section? Bli231957 (talk) 20:09, 21 June 2022 (UTC)
 Done
In the "Pharmacology" section, the last image is merely a repeat of one of the chembox images, and does the one about "diethylstilbestrol" fit in this context? Bli231957 (talk) 20:09, 21 June 2022 (UTC)
Looks like an attempt at showing the structure–activity relationships. I'll try and clarify with captions - but I'm also comfortable with deletion.
I would say maybe remove the last picture, but keep the other two. Bli231957 (talk) 19:11, 23 June 2022 (UTC)
I've had a crack at improving it first. Any opinions? --Project Osprey (talk) 11:23, 24 June 2022 (UTC)
Yes, I agree with the gallery change, but I still have a feeling that a duplicate picture feels strange. Maybe put another picture with a caption, then add the information you added in the caption of the duplicate picture in the text, then remove the picture. Bli231957 (talk) 15:43, 24 June 2022 (UTC)
I've redone it as a single image. --Project Osprey (talk) 14:37, 29 June 2022 (UTC)
Maybe add a comment on how Dinitrobisphenol A and p-tert-Butylphenol are related to Bisphenol A in the "See also" section. Also, p-tert-Butylpheol is a piped link, but the link is a redirect to 4-tert-Butylphenol. I would advise you to change "Para tertiary butyl phenol" to "4-tert-Butylphenol" in the piped link. Bli231957 (talk) 10:25, 28 June 2022 (UTC)
 Done I've restructured it a bit too. --Project Osprey (talk) 15:14, 28 June 2022 (UTC)
Looks great now. Bli231957 (talk) 16:05, 28 June 2022 (UTC)


### Response
I've started responding to these comments on the same line you've written them, my additions in italics. Not the normal way of replying to things, but it might help to keep track of each point. If it's an issue I can revert my comments and try another way. --Project Osprey (talk) 21:20, 22 June 2022 (UTC)

I think it's fine, no problem. Bli231957 (talk) 19:02, 23 June 2022 (UTC)
However, I've realised that you've put your comments before the [ reply ] text on my signing, so please can you try to move your future comments after the  [ reply ] ? That would be great. Bli231957 (talk) 19:04, 23 June 2022 (UTC)
I've checked the source code, and I didn't find a way to do that. Please could you open a new line instead? Bli231957 (talk) 19:05, 23 June 2022 (UTC)
I see you've straighten it all out. Thanks for that. --Project Osprey (talk) 11:25, 24 June 2022 (UTC)


### More comments
The article presents a readable description of a highly topical and sometimes controversial chemical.  Some thoughts that occurred to me but are not crucial: 

solubility of 300 g/ton of water (I like those practical units!) seems about right, in fact fairly high owing to the hydrophilic OH groups.
the prep of BPA is a premier example of a green chemistry process: A + 2B -->  C  + water.  And apparently very generalizable (all kinds of phenols and carbonyls), which is very cool. Its difficult to beat the price of acetone.  Also, for chemists, the prep is cute because phenol and acetone are coproduced by the Hock process.  That information is probably beyond the readership.
Would be nice to know: to what does BPA degrade?  It is popular and to some, heartwarming, that pollutants are degraded by organisms, but my guess is that at neutral pH in air, BPA undergoes some sort of autoxidation.
--Smokefoot (talk) 13:39, 28 June 2022 (UTC)

Thanks. Wikipedia's willingness to use 'ppm' as a unit is a pet peeve of mine; probably somewhere between meaningless and uninterpretable for novice readers - in this case it also focuses attention on the smallness of the solubility, rather than the utter enormity of available solvent. I'd never really thought of it as a green process but you are absolutely right, edits made to that effect. I did look at oxidation but I couldn't find a solid source and gave in, I suspect it biodegrades faster than any abiotic process. I expect photoxidation to be a path. I'll look again. --Project Osprey (talk) 20:04, 28 June 2022 (UTC)
There appears to be no properties section. melting, boiling solubility and flash are in the chembox. But two have no references. Solubility in other solvents may be significant. Also available is the crystal structure. I would guess spectrum info is also available, IR, MR. Graeme Bartlett (talk) 22:48, 28 June 2022 (UTC)

I've made a start. I don't actually have access the the crystal data beyond what CCDC shows. --Project Osprey (talk) 12:36, 29 June 2022 (UTC)


#### Checking in
I think I've addressed most of the comments raised so far. Outstanding are references for the density and water solubility in the chembox and a mechanism for abiotic decomposition. I'll continue to look for these. Additionally, this paper (doi:10.1021/jp503567c) looks to have information for Template:Chembox Thermochemistry but I don't have access to it. Are there any other issues? --Project Osprey (talk) 13:07, 1 July 2022 (UTC)

Maybe you could add a bit more of the suggestions from Graeme Bartlett (e.g. solubility in other solvents)? Also check here for more suggestions with the refs. The comments from Smokefoot might also be helpful. Bli231957 (talk) 19:00, 4 July 2022 (UTC)
OK:...
Solubility (from @Graeme Bartlett:): CRC Handbook lists some organic solvents for it, but it doesn't give numerical values of the g/ml sort (I've taken the liberty of assuming solubility in benzene = solubility in toluene. No one uses benzene anymore). This that sufficient? I could try tracking down a Technical Data Sheet from a supplier, the values would likely be accurate but the refence is unlikely to stay put.
Abiotic degradation (from Smokefoot): I've added a review ref which has a section on this. Did you want to know what it degraded into?
Secondary refs query list: I've addresses the points at that section. About half the questioned refs have been deleted. The others are either fine or have been reinforced. I remain unsure about the ERRγ binding study doi:10.1093/jb/mvm158. I'm not a pharmacologist. It appears well cited.
Density: I still don't have a reference for this. I suspect it might be included in the crystal data refs, but I can't access those. Done
--Project Osprey (talk) 13:51, 18 July 2022 (UTC)
As mentioned to Praseodymium-141 on their talk-page. I feel that I've completed all of the improvements requested. It would be regrettable if the review stalled this late into the process. Project Osprey (talk) 12:18, 2 August 2022 (UTC)
I don't feel like there's anything that could be added. I'll mark this as a pass. 141Pr 18:33, 2 August 2022 (UTC)

Ref #32 (doi 10.1002/14356007.a21_449.pub4) is indeed a review of solid acid-catalyzed condensations from a ChemE perspective.  BPA is mentioned 43x. --Smokefoot (talk) 13:53, 18 July 2022 (UTC)
Many thanks... is it mentioned in relation to polyetherimides? --Project Osprey (talk) 14:04, 18 July 2022 (UTC)
checking ....--Smokefoot (talk) 14:14, 18 July 2022 (UTC)
The article is not about polyetherimides (why would it be?).  It is about hydroxymethylations and a lot about BPA. Some tidbits:
"Two industrial processes are used ...  hydrochloric acid or ion-exchange resins,23,24 mainly sulfonic resins."
"The ion-exchange-resin-catalyzed process requires a treatment of the resin with an aminomercaptan... the promoter [is proposed to stabilize the] carbonium ion, which .. alkylates the phenol ring more rapidly."
"In the industrial process, bisphenol A is always produced (Scheme 4) together with sizable quantities of o,p‘-bisphenol A (o,p‘-BPA/BPA molar ratios up to 1:2)"!  The latter surprised me but makes sense.  Apparently methods exist to reverse the o,p' stuff into isopropenylphenol, which is recycled.  Your faithful servant, --Smokefoot (talk) 14:28, 18 July 2022 (UTC)
SciFinder leading me off in the wrong direction there. It's gratifying to see that most of those key points are already in the article but it leaves the question of polyetherimides unresolved. They clearly contain a BPA unit, and they have been made from BPA in the past, but are they mostly made that way? --Project Osprey (talk) 15:01, 18 July 2022 (UTC)
Kirk-Othmer encyclopedia on polyethers (doi 10.1002/0471238961.0118151323080920.a01): "The first aromatic sulfone polymer produced commercially was introduced as Bakelite polysulfone ...under the trade name Udel. .. made by reaction of the disodium salt of bisphenol A (BPA) with 4,4′-dichlorodiphenyl sulfone".--Smokefoot (talk) 15:28, 18 July 2022 (UTC)

Density of BPA from X-ray crystallography is 1.217 g/cm3 according to doi 10.1007/s10870-007-9207-8.    Other details according to Cambridge Xray database (to the extent that structures are reported to or collected by the database):
its CSD code is CEGYOC
The crystal structure has been reported 5x (an indication of the compound's signficance, most are reported only once)
The structures of 20 solvates have been reported (further evidence of some intense interest, BTW)
A fancy drawing of the Xray structure could be produced.  It doesnt tell the reader much.
--Smokefoot (talk) 14:14, 18 July 2022 (UTC)

Thanks. I think the crystal structure is of limited interest, even to professional chemists. Its not a hard molecule to picture, so I agree that an Xray structure probably wouldn't add much. --Project Osprey (talk) 08:15, 19 July 2022 (UTC)

There is a doi for the article in Berichte: 10.1002/cber.18920250333
--Stone (talk) 10:57, 19 July 2022 (UTC)

Cheers (ref 25 btw) --Project Osprey (talk) 11:56, 19 July 2022 (UTC)