Talk:Bisphenol A

Comment

I have merged the Bisphenol-A page into this page. 192.203.205.129 22:45, 17 May 2005 (UTC)

Its CAS#80-05-7 , EC{EINECS}#201-245-8 , RTK Substance#2388 , RTECS#SL6300000 ACX#X1002023-2

European Chemical Name: 4,4'-Isopropylidenediphenol

phytoestrogen?

This page appears to contain an error. This statement seems to be contradictory:

Bisphenol A is known to be an estrogen receptor agonist which can activate estrogen receptors leading to similar physiological effects as the body's own estrogens.[3]

However, wouldn't the latter half of the phrase imply this substance is a phytoestrogen rather than an estrogen receptor itself?Funsocaltiger 19:40, 20 April 2007 (UTC)

Phytoestrogens are secondary compounds found in plants, not synthetic ones from factories. The article says its an estrogen receptor agonist, which is a broader term that phytoestrogens also fit under. Bendž|Ť 20:44, 15 June 2007 (UTC)

Misleading Table

Dose (ppb)	Effects (measured in studies of laboratory animals)	Study Year
0.025	Permanent changes to genital tract	2005
0.025	Changes in breast tissue that predispose cells to hormones and carcinogens	2005
1.5	Low levels of human exposure from diet	2003
2	30% increase in prostate weight	1997
2.4	Signs of early puberty	2002
2.4	Decline in testicular testosterone	2004
2.5	Breast cells predisposed to cancer	2006
10	Prostate cells more sensitive to hormones and cancer	2006
10	Insulin resistance	2006
10	Decreased maternal behavior	2002
13	High levels of human exposure from diet	2003
20	Damage to eggs and chromosomes	2003
25	Health Canada provisional human exposure limit	1999
30	Hyperactivity	2004
30	Reversal of normal sex difference in brain structure	2001
50	U.S. human exposure limit	1998

This table is sourced to a globe and mail article not available for free. The table is also misleading. I know for a fact that the first two entries each refer to a single study that looked at mice and did reported dosages in micrograms BPA/kg body mass/day,not ppb. I have removed the table and recommend a discussion of the research rather than an oversimplification of the research. —The preceding unsigned comment was added by 74.75.205.209 (talk • contribs) 03:57, 11 May 2007 (UTC)

I added the table back in, with a citation back to a "free source", although scientific journal articles upon which much of the Wikipedia articles rely are usually not free either. The source, the Environmental Working Group's report on Bisphenol A in cans, also refers back to the original articles on which the doses themselves are based. I believe the notation, ppb, refers to μg/kg body mass/day (as is indicated in the text itself), is non-standard though it does appear elsewhere (see for example [1]), and has been changed. It seems the previous author (who chose not to sign their statement) was also complaining about the use of mice versus rats. It has been pointed out by vom Saal et al (see [2]) that at least some strains of rats are insensitive to any type of exogenous estrogen, hence, the use of other species. Lastly, the comment that "I know for a fact" does not hold much weight on such a public forum where one has no evidence of the author's credentials. However, at least according to the EWG table, the doses and effects are derived from two separate studies, both of which were included in the recent the Center for the Evaluation of Risks to Human Reproduction interim draft expert panel report [3] Kristan 23:29, 13 May 2007 (UTC)

I must say that this table is indeed quite alarming, and possibly misleading. If a dosage of 0.025 ug/kg/day (so 2 ug per adult per day) already leads to "permanent changes in genital tract", why is this not confirmed? The comments of the The National Toxicology Program (NTP)’s Center for the Evaluation of Risks to Human Reproduction (CERHR)may be less alarming and closer to the facts. Sikkema 13:56, 30 September 2007 (UTC)

I'm concerned about whether the numbers in this table actually reflect the research. If you go to the reference it names the original papers... which seem to disagree with the numbers given in the table. For example, a Kubo 2001 paper says "We administered BPA only to mother rats during pregnancy and lactation at a dosage of approximately 1.5 mg/kg per day far less than the no-observed-adverse-effect level (NOAEL; 50 mg/kg per day)...". So the dose at which these brain effects occur is 1500 ug/kg/day, while the table specifies says it's 30 ug/kg/day. Note that the NOAEL level is meant to be 1000x the recommended "safe" level (50 micrograms/kg/day), so this isn't just a difference of notation. (Okay, so I've only looked at one article, and only at the abstract, but I think this warrants further investigation.) Arg (talk) 22:26, 18 November 2007 (UTC)

The table that was copied here was from a Globe and Mail article, but mostly drawn from an EWG report. As the author of the EWG table I want to clarify a couple of things. There was indeed a citation error. The study referenced for "Reversal of normal sex difference in brain structure" year 2003--should be 2001. I regret this, and fixed the error here and on EWG's website. All the studies cited are all summarized in 2 publicly available documents. NIH-sponsored CERHR's recent review of bisphenol A [4] and a publication in Environmental Health Perspectives [5]. I removed the line stating that 13 ug/kg-day for high-end exposures from diet, because this fact was not part of EWG's report.

I want to clarify the EPA's Human Exposure Limit for those not familiar with the RfD process. In the late 1980s EPA selected the most sensitive study (at that point) which found no effects at an exposure of 50 mg/kg per day. They then divided that ingestion level by 1000 to add a safety factor to address the fact that people may be more sensitive to the toxic effects of BPA than the animals studied, and to account for other uncertainties. Thus EPA believes that an individual should be able to ingest roughly 50 ug/kg-body weight per day with out any concern for toxic effects. The subsequent findings of toxicity at much exposure lower levels indicates that EPA's calculations must be updated. Sonyala —Preceding comment was added at 16:54, 7 December 2007 (UTC)

The second column in the table is labeled "measured in studies of laboratory animals", yet includes rows that say "Health Canada provisional human exposure limit" and "U.S. human exposure limit". Were humans "laboratory animals" in these studies? If they were not, then they are not "measurements" at all, and suggest the removal from the table, the label can be changed, or the rows highlighted, any or all of which is accompanied by clear and unambiguous comment to the effect they are the result of some model, and affix the usual uncertainties from said modeling. (Indeed, given Kristan's comments, above, that you can pick and choose the species because "[...] at least some strains of rats are insensitive to any type of exogenous estrogen [...]", it leads me to wonder if this entire table is an NPOV violation at the source, without supporting evidence the un-identified lab animal in use in this table of data is equally or more sensitive than humans.) mdf (talk) 20:19, 8 December 2007 (UTC)

Another user added the human exposure limits, but I will highlight them. I think they are useful because they underscore that adverse effects have been observed at lower levels than traditionally regarded as safe. Risk assessment typically uses the most sensitive test in the most sensitive species of animal, and then divides the amount ingested by a safety factor to assure that human exposures are well below those that cause harm in a laboratory.

This table is peer reviewed scientific studies, and government-derived safety levels, so is still NPOV in my opinion. Sonyala —Preceding comment was added at 16:05, 11 December 2007 (UTC)

Are the human exposure limits in the table, as cited? If not, their inclusion may involve a WP:SYNTH problem here.

In any case, no one can dispute the the actual measurements. But it seems that the notion that it is altogether reasonable to find the most sensitive animal to some chemical and proceed to assume that humans are even more sensitive than that is debatable. By that kind of thinking we ought to be warning people of the intense danger to chocolate, onions, and other foods because they contain large quantities of chemicals that are toxic to cats and dogs. Of course, we don't have big, flashy, signs at the supermarket highlighting the risk of garlic to some lab animals, because despite all that undisputed evidence, we know from direct experience that these foods do not harm people. And while it is also true there is a physically plausible argument to the risk of bisphenol A roaming around in our bodies, if, according to Kristan's comments above, the sensitivity is substantially different even between strains of lab animal, why couldn't that happen between "strains" of people, or between people and lab-rats? This question may lead the intelligent reader to wonder if the table was a result of cherry picking "peer reviewed" results to produce a political/social/etc end, rather than an honest, dispassionate, assessment of the real risk to people. And this is why I raise "NPOV at the source" as a possible issue: yes, we are quoting a source accurately, but the source may have an agenda that needs to be aired fully.

Anyways, at least those rows of the table have been highlighted to reflect some measure of ignorance. It would be very nice to know if, in fact, the dangers to these substances have been shown to exist in people, or equivalently, the relative risk between these lab animals and people. Can we connect that table to the human reality? mdf (talk) 04:28, 12 December 2007 (UTC)

66.225.145.140 (talk) 19:44, 11 December 2007 (UTC) - I don't really have a claim to stake in this article, but as an average reader I do find this table alarming, particularly because it is so one-sided. Of all the studies of Bisphenol A only a dozen or so were selected for inclusion in this table and ALL of the selected studies show a negative effect. This is a biased representation of a topic that is clearly still in debate. If ALL studies showed a negative health effect, then the product would be surely banned in most jurisdictions.

I agree that this table is biased and poorly referrenced, and should be removed. The Environmental Working Group is an advocacy group, not a reliable source of scientific data. Under NPOV, I believe that this should be removed. A section in the article for the politics of this chemical would be OK, but referrences to science should be left to the peer-reviewed scientific literature. Pustelnik (talk) 20:35, 5 January 2008 (UTC)

This table does not differentiate between exposure in utero and exposure as an adult. That is important information, since effects could be very different for each. Is it possible to add the corresponding information for each row? Xwordz (talk) 16:47, 2 November 2008 (UTC)

Hazards

If you edit the page, under the hazards section, I have added the hazards as determined by http://www.wwf.org.uk/news/n_0000000145.asp, but as a comment. Every time I tried to add them as a fact, my computer would wreck the template, this accounts for all my edits and undos. Could someone please add them as a fact, then reference them to the aforementioned site? Thank you.

CERHR Interim findings

This seems a sensitive subject, so rather than edit into the main article, the Expert Panel's findings are now public.

The National Toxicology Program (NTP)’s Center for the Evaluation of Risks to Human Reproduction (CERHR) was established in 1998. The NTP-CERHR’s principal activity is evaluating chemicals – either naturally occurring, as in the case of phytoestrogens found in soy products, or synthetic, as in the case of BPA.

The CERHR conducts its work though specially appointed independent Expert Panels made up of scientists representing a range of relevant disciplines. The Expert Panel works with NTP-CERHR staff over a period of several weeks, prepares a draft report, and reviews and edits that draft at a public meeting over the course of several days. In the case of BPA, the public editing and review extended over two three-day sessions several months apart.

The Expert Panel has published Draft Interim findings at CERHR website. The final report is due to be published in the Fall of 2007.

The draft conclusions of the Expert Panel are divided into various groups of interest. The following quotes from the Draft Interim Meeting Summary:

• For pregnant women and fetuses:
  • The Expert Panel expressed some concern that exposure to Bisphenol A in utero causes neural and behavioral effects.
  • The Expert Panel expressed minimal concern that exposure to Bisphenol A in utero causes effects on the prostate.
  • The Expert Panel expressed minimal concern that exposure to Bisphenol A in utero potentially causes accelerations in puberty.
  • The Expert Panel expressed negligible concern that exposure to Bisphenol A in utero produces birth defects and malformations.
• For infants and children:
  • The Expert Panel expressed some concern that exposure to Bisphenol A causes neural and behavioral effects.
  • The Expert Panel had expressed minimal concern that exposure to Bisphenol A potentially causes accelerations in puberty.
• For adults:
  • The Expert Panel expressed negligible concern for adverse reproductive effects following exposures in the general population to Bisphenol A. For highly exposed subgroups, such as occupationally exposed populations, the level of concern is elevated to minimal.

It is my understanding that the terminology around the word 'concern'is more or less standard for CERHR Expert Panels. --Bob Herrick 22:08, 21 August 2007 (UTC)

Re missing citation on Bisphenol A synthesis

For what it's worth, Bisphenol A is discussed on page 218 of The Merck Index, thirteenth edition, under number 1296. Regarding its manufacture from phenol and acetone, it says "Jansen, *US 2468982* (1949); /Faith, Keyes & Clark's Industrial Chemicals/, F. A. Lowenheim, M. K. Moran, Eds. (Wiley-Interscience, New York, 4th ed., 1975) pp 149-152. /Review: Chem. & Eng. News/ *41*, 35 (June 3, 1963); /ibid./ *51,* 5 (July 16, 1973)."

(This doesn't mean much to me, but might save somebody else a bit of effort.) D021317c 22:00, 3 November 2007 (UTC)

Bisphenol A in the news

Bisphenol A was discussed on "The Newshour with Jim Lehrer" on October 30, 2007.

http://www.pbs.org/newshour/forum/health/july-dec07/bpa_10-30.html D021317c 22:16, 3 November 2007 (UTC)

NPOV ??

Regarding the note:

The independence of United States scientific panels from industry influence has been questioned however.[11]

It adds little and as the link no longer exists I'm removing it.

Regarding the note:

Furthermore, peer reviewed publications have appeared pointing out flaws within the chemical industry funded studies that report bisphenol A safety.

According to: http://www.stats.org/stories/2007/washington_obesity_mar12_07.htm Vom Saal's opinion itself is controversial. His opinion (while peer reviewed) is in the minority here and not part of a consensus. The article also mentions other papers reporting Bisphenol A safety that were not industry funded. As it stands, the wording is misleading and should be expanded to become more balanced or removed. —Preceding unsigned comment added by 216.16.228.6 (talk) 16:58, 21 November 2007 (UTC)

While there is indeed controversy about many aspects of BPA toxicity, it is inappropriate to use statements by PR firms, such as STATs to refute peer-reviewed publications. vom Saal's publication reporting systematic differences between industry-funded and academic studies was published in Environmental Health Perspectives, a leading journal as measured by the impact factor.

A consensus statement about the potential adverse health effects of current human exposures grew out of an NIEHS-sponsored panel and is co-authored by 38 government and academic researchers, and in press at Reproductive Toxicology. .

While my position may not be NPOV as I work with Environment Working Group. The author of the above statement, "[vom Saal's] opinion (while peer reviewed) is in the minority here and not part of a consensus," should identify themselves by creating a wikipedia a log in and cite more reputable sources. (Sonyala)

I agree, Sonyala. Will you list your qualifications on your user page? The Environmental Working Group can also be considered to be a PR organization, rather than a scientific one. Please tell me where "Environmental Health Perspectives" is rated as a "leading journal".Pustelnik (talk) 21:01, 5 January 2008 (UTC)

Some of the current article is speculation or synthesis verging on research. This encyclopedic entry is about a chemical compound that has significant technological implications resulting from its structure and functionality. Yet only a small fraction of the current content is dedicated to this chemical functionality and utility. Even though I happen to be sympathetic to the concerns, matters of health and toxicity are covered in the MSDS more authoritatively than any of us could achieve. In certain cases, cyanide poisoning (and probably something related to estrogen mimics?), focused articles have been developed in which case the reader can be directed to those sites without diluting what is inherently a chemical discussion with protracted commentary/speculation/warnings on perceived health benefits or problems.--Smokefoot (talk) 21:34, 5 January 2008 (UTC)

Kudos & questions

This is a very interesting article and debate - the kind that adds to Wikipedia's good reputation IMHO. Kudos to all for watching the rigor and the debate. Three questions. 1) How can this be nominated to go from mid-level to high-level importance? I was just looking here because of a news article I had just seen about the chemical, and one can imagine this chemical will become a more important subject of scrutiny given the possible health risks. 2) How can this be nominated for a featured article? Much more important than some of the trivial topics that get selected for article-of-the-day. 3) I think the intro section, the initial paragraph, should say something about the chemical's significance to industry as well as to the possible health-risks. You don't get to that until long after the chemical analysis, and I think most readers would want to see in the lead some sense of the "notability" (to use a Wikipedian term) of the topic. Also, a guide as to how to tell which bottles contain bisphenol A would be useful, if there's for example, one of the recycling codes that it would refer to. Thanks! Bruxism (talk) 21:59, 23 December 2007 (UTC)

Metabolism ?

What if any are the metabolites of this plastic in the human body, and how do bacteria (gut and the environment) metabolise it?

71.114.183.105 (talk)

Major move of content proposed

The content related to estrogen-like properties of bisphenol A would probably be more suitably relocated to Endocrine disruptor. We made a similar move with cyanide poisoning from cyanide. Left behind after the move are 2-3 sentences summarizing the nature of the controversy, so that readers are aware of the connection. The technology on bisphenol A is huge (many millions of kg are produced) so it is likely that this article will eventually become quite chemical. Comments or alternative ideas are welcome. Maybe there is a better place to move the content to allow the biomedical-legal aspects to fluorish. Again the cyanide poisoning article has been well received, judging from the level of attention it gets. --Smokefoot (talk) 03:51, 6 January 2008 (UTC)

Disagree—endocrine disruptor deals with all compounds with estrogenic effects. This article is the logical place to discuss risks specifically from Bisphenol A. Of course, this does not preclude more discussion of the chemistry of Bisphenol A. Spacepotato (talk) 04:49, 6 January 2008 (UTC)

Agree with Spacepotato. Two or three lines on this page is not NPOV when you consider the amount of attention its receiving in the media currently. OptimistBen (talk) 05:52, 18 April 2008 (UTC)

Baby bottles

The quote in the following lines:

In January 2006, the German Federal Institute for Risk Assessment announced that polycarbonate baby bottles are safe, stating that published research is "difficult to interpret and [is] occasionally contradictory".[26]

should be replaced because on examination of the reference this quote is seen to be about the health effects of bisphenol A.

I suggest it is replaced with the following quote with the same reference "The BfR does not recognise any health risk for babies that are fed using baby bottles made of polycarbonate"Brentsalmon (talk) 12:34, 8 March 2008 (UTC)

More Resources on Human Exposure

The following link is to a PhD thesis by Laura Vandenberg, a recognized expert on Bishphenol A. It has a great amount of information that could help improve this article Vandenberg: Human Exposure to Bishphenol A. I am also adding this to the external links.Enviropearson (talk) 02:13, 29 March 2008 (UTC)

Green? Hardly

I removed the text:

methodology is an example of a "green chemical reaction" in the sense that the process

For the primary reason that if one is engaged in the production of the compound that is the subject of this actual Wiki article, one is hardly engaged in any sort of green chemistry! One is instead making a toxic compound that is leached out of plastics! To make the case that polycarbonate could be made from naturally obtained phenol and acetone does not even justify this, as natural ethanol can also be processed into ethylene capable of being used to make standard polyethylene plastic... which happens to not hydrolyze into toxins... Zaphraud (talk) 03:49, 30 March 2008 (UTC)

Totallydisputed

Lots of wildly inaccurate material in this article, from the mischaracterization of scientific studies to the false statements about the meaning of recycling codes. See http://www.factsonplastic.com/today-show-bisphenol-release/ -- RDM2008 (talk) 06:32, 17 April 2008 (UTC)

I don't think RDM2008's allegations suffice for qualifying this page as "totally disputed":

• www.factsonplastic.com is an advocate group publication (copyrighted by the American Chemistry Council (ACC) which "represents the leading companies engaged in the business of chemistry") and as such unfit to support a claim of lacking neutrality.
• "Mischaracterization of scientific studies" is too general a claim to verify or even discuss (it basically means "the scientific basis for this article has been misread", right?). Which studies have been mischaracterized in which specific way?
• "False statements about the meaning of recycling codes" were made in the article's text ("Type 7 plastics, such as polycarbonate plastic and epoxy resins, are made from BPA monomer" is indeed wrong, since the latter part of the sentence syntactically refers to the whole group of #7 plastics, not only to the polycarbonates) but the table stated correctly "Other". I am going to correct which is a mere wording error. The point is that a #7 on the baby bottle is a strong indicator for polycarbonate because the other materials used for bottles would have a recycling code of their own.

Does any of the main contributors to this page feel the tag should be removed, as I do?

Peter schneider (talk) 10:27, 17 April 2008 (UTC)

I think that the article has become a virtually single author report (Wikipedia:Ownership of articles). This chemical has had a massive technological impact in modern society, yet the article has been transformed into a sort of forum on endrocrine receptor aspects. Including such tangential gems as "Some hormone disrupting effects in studies on animals and human cancer cells have been shown to occur at levels as low as 2–5 ppb (parts per billion). It has been claimed that these effects lead to health problems such as, in men, lowered sperm count and infertile sperm." (True possibly, but relevant to BPA?) It is disappointing that an issue as serious as endrocrine competitors is handled in such a biased manner so that the article loses the very impact that the most fervent editors seem to be seeking. It is also disappointing that, in an article about a hugely important chemical compound, the writing is so non-chemical. It is not difficult to Google toxicology studies and paste-in that information. A more demanding editing job entails parsing that information (tox researchers, like chemical factories, produce, period, whether their product is good or mediocre, they must produce, i.e. publish) and placing such information in the context of a very important chemical. So yes, I think that the article has unfortunately veered toward, not quite a rant, but a grab-bag of claims, including those that are anecdotal or alarmist. Speaking for my personal views, I find the endrocine receptor aspects deeply disturbing, but at the same time I assert that the current tone and content are often unenlightened, glib, and unbalanced. For these reasons, I have just stayed away from editing this thing. It's too bad but we've seen the process before - time and some balanced editing will eventually aneal this article into a good one.--Smokefoot (talk) 13:19, 17 April 2008 (UTC)

I don't see what is disputed here. If there are specific things that are wrong or debatable, please point them out. In the meantime, I'm removing the tag. Also, factsonplastic.com in no way trumps the variety of sources we've got represented in the article. Finally, I agree this article could use more info on the uses of bisphenol A, and I encourage editors who are interested in and/or familiar with its uses to add this information.—Preceding unsigned comment added by Yilloslime (talk • contribs)

What is disputed here is the one-sided and fictional material included in the article, and the truth that is omitted. Perhaps the industry website is incorrect, but it is a notable point of view and a reliable source that must be included. Please do not remove the tag until there is consensus that the NPOV and accuracy problems have been resolved. RDM2008 (talk) 18:32, 17 April 2008 (UTC)

RDM, I understand that you think the article is biased, but that alone does not justify the {{TotallyDisputed}} tag. You haven't pointed out a single factual error in the article, so your claim of "fictional material" is pretty thin. If you see something incorrect in an article, the first step is to fix it, not to drop a tag on the article. If your attempts to fix it meet resistance, then you take it to the talk page. And if you can't sort out your differences quickly, then maybe you drop a tag on the article. Likewise, if you think that an important POV is not represented in the article, then the appropriate course of action is to try to introduce that perspective into the article. Only if that fails should you consider the tag. In short, why don't you try improving the article before simply tagging it. Remember: be bold! And if you meet resistance, then maybe you can consider applying the tag, but only if you are prepared to make a case on the talk page about specifically what is "fiction" and how the article is "one-sided". So far, I haven't seen any of this from you. Yilloslime (t) 19:11, 17 April 2008 (UTC)

actually, the fact that i think the article is biased does justify the tag. i've pointed out several factual errors:

• the recycling chart is utterly irrelevant to BPA, and misleading, as it's for sorting garbage, not for determining health factors.
• the article relies on the environmental working group, which is not credible.
• the article is one-sided, citing only studies supporting claims of carcinogenic result, when there are far more studies showing no such problem
• the article fails to provide the industry point of view
• the article fails to note that "some concern" is a low level of concern, and that, for most categories of BPA use, the government's official position is the even lower "negligible concern."

multiple editors have said there are problems with the article. according to WP:NPOVD, that means the tag remains. please return the tag. RDM2008 (talk) 20:14, 17 April 2008 (UTC)

• Recycling chart is not irrelevant or misleading.
• Article does not rely on environmental working group.
• Of course industry-funded research does not find any problems with BPA.Bisphenol_A#cite_note-22
• Feel free to add industry POV.

--Bork (talk) 20:55, 17 April 2008 (UTC)

"yes it is" "no it isn't" is not productive and i will not play that game. i've given cites and they've been ignored. i did add industry perspective by tagging the article and indicating what was wrong with it. the tag was improperly deleted. i don't wish to edit war but ask that the tag be restored. RDM2008 (talk) 21:32, 17 April 2008 (UTC)

I have tried to add, not an industry point of view, but a point of view that does not enhance the negative image portrayed in the extended section on hazards. My edits have been removed, disputed, and questioned, while the toxicology section grows daily. I think again that this article deviates from NPOV and pushes an agenda by Yellowslime. And when some editor tags the article as being needful of a rebalancing, that editor's tag itself is rapidly removed and the poor editor is accused on being a "tagbomber." I agree with several of the comments of RDM2008, but now that editor has or soon will be chased off. Qualified editors with diverse perspectives, especially those with technical backgrounds, avoid this article because it has become virtually a private garden tended by a handful of editors whose main advantages is not knowledge, but the time that they are willing to dedicate to weeding out statements that dont conform to their perspectives. The performance is no crisis and its just part of life in WE, but it is really disappointing because the collective effort of editors from diverse perspectives could have accomplished something here.--Smokefoot (talk) 22:21, 17 April 2008 (UTC)

RDM, in contrast to your assertion, tagging the article with {{totallydisputed}} in no way adds the industry perspective. The only way to add the industry perspective, would be to actually write about the industry perspective, which you haven't even attempted to do, and no one is stopping you from doing. On the contrary, I've encouraged editors to add it in. And while I'll agree that "'yes it is' 'no it isn't' is not productive", you are in fact playing just that game when you say that the recycling table is "irrelevant" without saying why you think that.

Smokefoot, I'm curious what you think my agenda is, and I'm also wondering which edits of yours have been "removed, disputed, and questioned". As far as I can tell, you've made 6 edits to this page in the last few months, and with the exception of this edit deleting an entire section, which you made without any talk page discussion, your contributions are largely intact. I'd also love to see some evidence for this statement: "Qualified editors with diverse perspectives, especially those with technical backgrounds, avoid this article because it has become virtually a private garden tended by a handful of editors whose main advantages is not knowledge, but the time that they are willing to dedicate to weeding out statements that dont conform to their perspectives." Who are the editors that have sworn off this page? It's news to me that anyone is avoiding this page. It's also news to me that this is a cabal-controlled article. Finally if you are implying that I WP:OWN this article, I think that's laughable. When I started watching this page it looked like this. Since then, I've added a few things and rearranged things a bit, but the text of the article is pretty much the same.Yilloslime (t) 23:36, 17 April 2008 (UTC)

one of many npov violations

Missing from the article is the NTP's relevant conclusions, http://cerhr.niehs.nih.gov/chemicals/bisphenol/BPADraftBriefVF_04_14_08.pdf:

The NTP has negligible concern that exposure of pregnant women to bisphenol A will result in fetal or neonatal mortality, birth defects or reduced birth weight and growth in their offspring.

The NTP concurs with the conclusion of the CERHR Expert Panel on Bisphenol A that there is negligible concern that exposure to bisphenol A causes reproductive effects in non-occupationally exposed adults and minimal concern for workers exposed to higher levels in occupational settings.

I am readding the tag, as no one has adequately defended its removal against the complaint made by two users on this talk page about the unbalanced nature of the article. RDM2008 (talk) 04:19, 18 April 2008 (UTC)

Question to RDM: Why not simply add this material directly to the article yourself, rather than simply tagbombing and doing nothing to fix the perceived problem? Yilloslime (t) 04:26, 18 April 2008 (UTC)

Two thirds of the article needs a complete rewrite. I'm not experienced enough to do that in one go.

More missing stuff:

• http://www.bisphenol-a.org/whatsNew/20071101.html

In the human body, bisphenol A is efficiently converted to a metabolite known as a glucuronide,(2) which has no known biological activity and is rapidly and entirely excreted into urine. Before analysis, human urine samples are first treated with an enzyme that hydrolyzes the glucuronide back to bisphenol A, which is easier to measure. Although bisphenol A is measured and reported by CDC, this does not mean that bisphenol A itself is present in the body or in urine.

blatant copyvio removedNil Einne (talk) 10:19, 17 February 2009 (UTC)

Yilloslime's edit does not fix the NPOV problem: the page is still one-sided, because the truth is buried in one sentence deep within layers of quote-mining. The inaccurate recycling information still hasn't been removed. RDM2008 (talk) 04:56, 18 April 2008 (UTC)

RDM. Thank you for finally providing some concrete examples of what you think is wrong with article. I added in the NPT's other findings as you suggested. If you think they can be expressed better, please feel free to modify the section or suggest a change here on the talk page. Simply stating that "the truth is buried" isn't very helpful. Likewise, what exactly about the "recycling information" is inaccurate. Finally, this edit to this talk page is a blantant WP:COPYVIO from here. I'd remove it myself, but I don't want to look like a dick. At any rate, you do raise a good point in that there have been several biomonitoring studies for BPA and none of this info is mentioned in the article. I'll try to add something about it, but I encourage you dive in yourself and try to improve things. Yilloslime (t) 05:26, 18 April 2008 (UTC)

I believe I've addressed every specific, actionable issue brought up by RDM, so I am removing the totally disputed tag, per WP:TAGGING "any editor who sees the tag but does not see any problem with the article and who does not see any detailed complaint on the talk page should feel free to remove the tag and note on the talk page that they are doing so." Also, editors should keep in mind that per the intro to WP:NPOVD: "Drive-by tagging is strongly discouraged. The editor who adds the tag must address the issues on the talk page, pointing to specific issues that are actionable within the content policies, namely Wikipedia:Neutral point of view, Wikipedia:Verifiability, Wikipedia:No original research and Wikipedia:Biographies of living persons. Simply being of the opinion that a page is not neutral is not sufficient to justify the addition of the tag. Tags should be added as a last resort." And in the future please be sure you are using the appropriate tag. {{TotallyDisputed}} "is a combination of Template:Disputed and Template:POV. Consider using one of those templates instead, if appropriate."[6] While eventually RDM did point out some specific things he felt violated NPOV (and I amend the article accordingly), he still hasn't brought up any specific factual errors, and therefore he probably should have used {{POV}}. Finally, if you see a NPOV problem or factual error in a page, the best and first course of action is to jump in and fix it yourself. Tags should be added as a last resort. In my opinion, and I'm pretty sure I've got wikipolicy on my side here, RDM has/had the cart before the horse. Yilloslime (t) 15:43, 18 April 2008 (UTC)

One small point I'd like to mention is that Germany has certified BPA as non-harmful, yet the wikipedia page only mentions the countries that are proposing legislation against it. Seems very lop-sided to me. Check out Germany's Federal Institute For Risk Assessment (BfR) Joins FDA, Others, In Affirming Safety Of Bisphenol A Could we balance the BPA bashing with this? --Angryapathy (talk) 17:41, 9 October 2008 (UTC)

"EFSA has issued a statement regarding the conclusions of a study published in the Journal of the American Medical Association. The European Commission asked EFSA to rapidly assess the relevance of this study and its implications for hazard and risk assessment of Bisphenol A. Read more in our key topic section." The EFSA statement was issued on October 24, 2008. Should this be referenced in the section on the Lang study? EFSA's conclusion was that "This single study does not provide sufficient proof for a causal link between exposure to BPA and the health conditions mentioned above. Therefore, EFSA considers that there is no need to revise the TDI as derived by the AFC Panel in 2006." [7] --195.216.7.115 (talk) 14:52, 28 October 2008 (UTC)

Identification of Plastics

1. 7 should be Polycarbonate (PC). Someone keeps changing it to Other. —Preceding unsigned comment added by 24.201.230.216 (talk) 14:19, 17 April 2008 (UTC)

Why do you think recycling code 7 equals (only) Polycarbonate? Cf. International_Universal_Recycling_Codes, and if you don't trust wikipedia, cf. the first hand source from the SPI who conceived the codes http://www.plasticsindustry.org/outreach/recycling/2124.htm: 'The SPI coding system also includes a seventh code, identified as "other." Use of this code indicates that the product in question is made with a resin other than the six listed above, or is made of more than one resin used in combination.'

This should end this discussion.-- Peter Schneider (talk) 16:46, 17 April 2008 (UTC)

Also: http://www.americanchemistry.com/s_plastics/bin.asp?CID=1102&DID=4645&DOC=FILE.PDF

The recycling codes have nothing to do with BPA, and should be omitted entirely if the article is ever going to lose its totally disputed tag. Resin codes 3 and 6 are based on monomers that don't always have BPA. RDM2008 (talk) 04:46, 18 April 2008 (UTC)

The codes identify what kind of plastic an item is made out of, and thus are useful for identifying items that may leach BPA, which is why the table, or at least the information in it, is relevant to the article. And don't see how is it "misleading" or "inaccurate" as you have claimed without explanation in posts above. I do think, however, that the section Bisphenol_A#Identification_in_plastics is probably overkill and could be trimmed. I'm on it. Yilloslime (t) 05:35, 18 April 2008 (UTC)

this is why no one trusts wikipedia

As documented above, the page is one-sided quote-mining, anti-scientific, ignores the substantial evidence for BPA safety, but it's a waste of my time to edit-war with activists who refuse to follow Wikipedia rules and suffer no consequences for refusing to adhere to NPOV or NPOVD. I've documented why the tag should remain, other users agree, but Yilloslime repeatedly removes the tag without discussing or addressing the problems. Administrators should do something about his refusal to collaborate and the WP:OWN violation. The tag indicates the existence of a dispute, and Yilloslime is affirmatively misleading people with his disruptive edits. Shame on Wikipedia. RDM2008 (talk) 04:55, 18 April 2008 (UTC)

The page looks good to me; all assertions are based on consistent scientific findings. If you want to add things, you can, although they should be said in the context of all the opposing information. If you find something worth adding, add it. But don't put tags up that don't reflect the truth. And try not to use the Talk page as your soapbox. OptimistBen (talk) 06:07, 18 April 2008 (UTC)

---

I wonder whether one shouldn't condense the discussion about the health effects to about two sentences, citing the two irreconcilable POVs, including a bullet list of health concerns. Cf. the Epoxy article which has to deal with the same problem as this article. It just refers to a comprehensive Greenpeace paper which cites many original sources (vom Saal etc.). Opposing that with a reference to the industry page http://www.factsonplastic.com would certainly provide the amount of neutrality required. Providing additional sources in footnotes would certainly be ok.

I understand and partly agree with the idea that this page is not the place to give a detailed overview of the latest state of research; perhaps it should indeed rather provide interested readers with the means to do the reading and form their own opinions.-- Peter Schneider (talk) 14:07, 18 April 2008 (UTC)

Here's what I think would improve this page.

• More info on uses, including

• production statistics,
• why BPA is added to some plastics--i.e., what properties does it impart, etc.

• More on the chemistry of BPA

• perhaps the polymerization rxn, although it is already discussed here
• how BPA functions as an antioxidant
• other useful reactions of BPA

• More info on environmental fate
• Significant tweaking of the the health effects section

Given the vast amount work that been done on the health effects of BPA and the media attention to the topic, it definitely deserves way more attention in the article than just 2 sentences as suggested by Peter. However, what we've got is far from perfect. I think the section should rely mostly on secondary sources: review articles in scientific sources, the expert panels, risk assessments by governments (e.g. EPA, NTP, Health Canada, etc.) and intergovernmental associations (IARC, WHO, etc.). Maybe we cite a few key primary research papers, but I certainly don't think we need as much attention to the primary literature as we have now, and I'm not sure that the studies that are included now are the most appropriate ones. This article definitely should not cite every study that's ever been done. There have also been a lot of biomonitoring studies (CDC, etc.), and these aren't mentioned at all. They should be (IMHO).

What we've got now is far from perfect, but it's even further from being inaccurate or totally disputed.Yilloslime (t) 15:22, 18 April 2008 (UTC)

My problem with how the scientific findings are sourced is that they're taken out of context. You shouldn't quote a fetal hormone study and not say as such, as this implies that it messes with adult hormones with equal effect. The same thing happens in many other wikipedia articles, where raw, high-dose carcinogen studies based on mutagenesis are favored over appealing to actual authorities on translating such data. I don't trust anonymous authors on wikipedia to properly contextualize journal articles involving the words "toxin" or "carcinogen", and so citations should instead be made to secondary authorities on the subject. It's astoundingly easy to cherry-pick your way through journals and cite articles to non-scientists in support of your claim, whatever it may be. Lesser sins involve citing journal conclusions as fact when the articles themselves show only correlation, not causation, in failing to carry-over the journal article's sense of confidence in the findings, or in ignoring journal-published responses to the journal article in question.--67.171.22.86 (talk) 07:54, 25 April 2008 (UTC)

Identification in Plastics

The final section of this article is titled "Identification in Plastics" and discusses plastics in packaging and leaching, so I think the previously removed paragraph needs to be added back in, as it further discusses the possibility of leaching. —Preceding unsigned comment added by Mlamb1 (talk • contribs) 20:54, 28 April 2008 (UTC)

I removed that paragraph since it's not actually about Bisphenol A, the topic of this entry. In fact, neither bisphenol A nor polycarbonate plastic is even mentioned in the passage. The info discussed might be useful to include somewhere in this encyclopedia, but not here. Why do you feel it should be in this article? Yilloslime (t) 21:10, 28 April 2008 (UTC)

Bisphenol A is used in the passage. '...but these resins do not use bisphenol A during polymerization and package forming.' I think it should be in this article because just as a reader wants to know which plastic can contain BPA, he or she also wants to know which plastics don't use BPA, especially if there has been an erroneous statement in a public printed piece as was the case with the Environmental Health Perspectives magazine article that was then corrected (hence the reference to EHP.)

Mlamb1 (talk) 12:32, 29 April 2008 (UTC)

I don't really think that the EHP article has led to wide spread confusion about which plastics leach BPA. Still, I still see your point, but I trimmed the section down, while still making it explicitly clear which plastics don't contain BPA. I removed sentence about terephthalates, though, since it's pretty far off-topic. Yilloslime (t) 15:26, 29 April 2008 (UTC)

Misleading Table - Redux

This table is bizarre and nonsensical. The lower the amounts of BPA involved, the worse the consequences? Is this homeopathy? Can someone restore the NPOV tag that this desperately needs? Joseph N Hall (talk) 18:54, 22 May 2008 (UTC)

Actually I looked at this further and of the half dozen articles I read (a couple fairly carefully), the exposure levels were those applied to mice and rats. So we have two egregious problems -- a) what if any statistics can be used to scale 'rodent exposure' to 'human exposure', and b) what studies are there that show a link between effects in rodents and effects in humans. You can't put human exposure limits in the same column as the numbers from animal studies! If BPA is mutagenic, it's mutagenic, but this table is made from whole cloth. 65.113.40.1 (talk) 22:15, 22 May 2008 (UTC)

And so - I deleted this table. I don't have any objection to tables filled with dire content, but this one didn't even pass the laugh test. You have values from tests conducted on different species under different protocols accompanied by one-line summaries that constitute original research in the way they draw brief conclusions from lengthy conclusions in papers. And those values are mixed in with human exposure limits set through processes and testing that aren't even documented or directly available here. It's not apples and oranges, more like apples and rocks. Editors on Wikipedia can't go around creating their own metastudies (which is what this table is, or was). 65.113.40.1 (talk) 22:27, 22 May 2008 (UTC) (these last two entries are mine - I got logged out somehow. Joseph N Hall (talk) 22:29, 22 May 2008 (UTC))

I put the table back in. It has been a part of the article for quite sometime, and so in the absence of consensus to remove it, it should stay.

To respond to 65.113.40.1: The use of animal studies to assess the risks of chemicals to humans is standard practice in risk assessment, and "safe" levels for human exposure are routinely estimated/extrapolated from such studies. See Reference dose for an example, and the US and Canadian risk assessments linked in this article for more gory details. That the studies in the table are in rodents should have been apparent from the heading of the second column, but I've modified the title to make it even more obvious.

To respond to Joseph N Hall: inverse or U-shaped dose-response curves are possible and not uncommon for endocrine disruptors. See for example this or this. Furthermore, the various studies were conducted on different species and strains, with adult, young, or pregnant animals, used different dosing schedules, and evaluated different end points, so even without invoking a non-monotonic dose-response curve, there's nothing weird about the table showing that "lower the amounts of BPA involved, the worse the consequences." Finally, the table is not original research. It is a adapted from a table in a report by the Environmental Working Group that subsquently appeared in the Globe and Mail, and the study descriptions in the article are taken from the EWG report verbatim. So no, wikipedia editors have not created their own meta-study here. Yilloslime (t) 23:55, 22 May 2008 (UTC)

I appreciate that you have made some changes that indicate that animal studies were involved. However, I have other concerns. Please don't see me as an advocate for one position or another. I really don't know that much about it except for a few common-sense rules of thumb that have always served me well both in life and as, in the past, an author of a technical paper or three, articles, and a book. This table juxtaposes an animal study that found weirdly low levels of BPA producing very significant changes in reproductive morphology of mice, with what are merely recommended levels of human exposure. I'm not aware of any way in which the article presents a well-founded relationship between both sets of numbers. Including both in the same table is provocative and is definitely not neutral. As a chemist who has presumably authored or co-authored peer-reviewed papers, do you think that such a thing would ever be permitted in a refereed journal? Your choices are a) no and b) hell, no. I think the appropriate thing would be to separate the tables. If there are human studies to present along with the government recommended maximum levels of exposure, I think they would be quite useful there.

(Cont'd) In addition, the tables should present results of similar importance and weight that show 'no' effects, should they exist, and on the face of it, they do exist. Undoubtedly there are reputable studies that show no statistically significant effects at levels that are within the bounds of the disturbing negative effects that are presented. For one thing, the studies that led to the initial safe exposure levels presumably followed the 'determine a level of exposure without ill effects and divide that by 1000' methodology mentioned elsewhere in the talk page. Perhaps the methodology there was flawed; presumably it was different.

(Cont'd) But then, there is, again on the face of it, room for criticism of the studies that you quote. Were they blind? The two or three I looked at were not blind. Studies where researchers are looking for a very specific effect and perform experiments that are intended to elicit that effect are 'investigative', are notoriously unrepeatable, and in a larger context are often less significant. Of course it's not the role of Wikipedia editors to perform studies on the studies (that is original research), but it is the role of editors to attempt to assign weight to the material presented subject to a reasonable consensus evaluation of its quality. A large, lengthy, randomized blind study of human or primate subjects would have to carry more weight than a small study of mice implanted with osmotic pumps in the most vulnerable stages of embryonic development. The article shouldn't fail to present research that suggests a safe level of exposure, if such research exists - either present or past.

(Cont'd) I simply want to see data presented in a neutral, unbiased way that leads readers to consider investigating all aspects of what is a controversial, sensational, and alarming topic. I hope that sounds reasonable. Joseph N Hall (talk) 05:43, 23 May 2008 (UTC)

It's not our place to critique the individual studies, that would be WP:OR. Suffice it to say that they were all published in peer reviewed journals, and then EWG thought they were of sufficient quality to include in their report, and the Globe and Mail though the EWG table was trustworthy enough to reprint. Furthermore, as indicated in the EWG report([http://www.ewg.org/node/20941}), most of the studies were also included the CERHR report and judged by CERHR to be moderately to highly useful for assessing the risks of BPA to human reproduction. I would be OK with removing from the table the few studies considered by CERHR to be of less than moderate utility or not included in their study at all. (I think it's only 1 or 2 anyways.) I don't see an inherent problem with including the US, Canadian, and EU reference doses along side these studies, and if I were writing a scientific paper on this I wouldn't hesitate to include such a table. However, the EU and Canadian RfDs are not included in the EWG report, so in the name of scrupulously avoiding WP:SYN, I'll remove them. Yilloslime (t) 06:12, 23 May 2008 (UTC)

I'm not objecting to a list of human exposure levels or levels from human studies. It's just that the numbers for humans don't belong in the same column with numbers for rats and mice. And you wouldn't get away with putting the numbers in the same column in the same table. Stop and think about that for a second, which should be a second too long. It's like a page right of How to Lie with Statistics. So is bolding or highlighting human exposure levels (which are not direct experimental results and are incongruous there as well) as if they were most important. Joseph N Hall (talk) 06:40, 23 May 2008 (UTC)

As for the highlighting of the RfD, I don't really care one way or another—I think others have argued on this page that they should be rendered differently from the rodent results to avoid confusion. And I'm not getting you're argument about not including the two types of data in the same table. You've claimed it wouldn't be allowed in a journal article (which this is not anyway), but haven't explained why. Yilloslime (t) 15:01, 23 May 2008 (UTC)

I'd argue that the table itself and controversy does not make much sense unless the context for "low dose" is clearly laid out somewhere. This is currently accomplished by including and highlighting the RfD in the table. Another approach would be to list the study that the current risk assessments are based on (a 1982 NTP study with a LOAEL of 50,000 μg/kg/day - the risk assessors chose an uncertainty factor of 1000 in order to derive an RfD of 50 μg/kg/day for humans - see [8]) and choose a series of the 100+ studies since 1982 that show effects below the effects found in the 1982 study. Because of the way risk assessments are conducted, I would argue that it makes more sense to include and highlight the RfD and include some of the 30+ that show adverse effects below this level. However, providing context could also be accomplished by including the RfD in the title/caption for the table. Kmarkey (talk) 11:18, 28 May 2008 (UTC)

I hear what you're saying about context, low dose v "regular" dose, and including the 50,000 ug/kg/day. The problem I see with adding that particular study (or most any study to the table) is that doing so might constitute WP:SYN. It's not really for WP to select a subset of studies and put them in a table and say that these are somehow important. The only reason the table in it's present state works is because someone else put it together, and then it was even republished by someone else. So I don't think we can just add another study not included by the source. But I agree that context is needed. I just think it would be best to give it that context by including some relevant discussion in the article, rather than putting another line in the table. For the record, I'm not opposed to giving the table a more descriptive name or including explanatory footnotes. Yilloslime (t) 15:47, 28 May 2008 (UTC)

This data is also available as individual peer-reviewed scientific articles, summarized in a single article, and detailed at the Endocrine Disruption Exchange. [WP:Syn] not only does not prohibit summarizing source material from original research, it calls editors to actively summarize material to adapt it for Wikipedia. Indeed this is already occurring, as various editors have excluded different pieces from the original EWG table (only including rat and mice studies, only including studies that CERHR called of moderate utility or above, several columns are missing, etc.). The debate (and various versions of the table) already exists in the mainstream, the question becomes how to summarize the findings for the purposes of Wikipedia. As a comparison, it would not be possible or desirable to describe every global warming study, so Wikipedia summarizes with a few choice articles (120 out of 10,000+). Kmarkey (talk) 09:19, 29 May 2008 (UTC)

Continuing the comments of Hall, and Kmarkey, the article is ridiculously biased. The US government (the FDA), the EU, the japanese, all hold that 50 microgrammes/kg is a safe dose; and they have good reason for doing so. This article only puts the perspective of the studies that have found "low dose" effects. The point of good editing is to make plain why there is a disagreement. The disagreement is because studies performed to Good Laboratory Practice find that the LOAEL is 50 mgs/kg, and this is what governments (including Canada) rely on. I have therefore included the relevant references in the table.

there's nothing weird about the table showing that "lower the amounts of BPA involved, the worse the consequences."

This statement is amazing. Pharmacology, as a discipline, rests on the concept of the law of mass action to describe how chemicals interact with a receptor. You can get physiological antagonism between two different receptors; but you will always find that below a certain concentration, the lower the dose, the less the consequence. Without any known exception. —Preceding unsigned comment added by 82.7.75.23 (talk) 00:41, 10 January 2009 (UTC)

One of the problems both with the overall premise of this article and with what you just said is that most substances exhibit a U-shaped dose-response curve. Some degree of hormesis. Things that are bad for you in large doses are quite often good for you in small doses - biological systems react to a toxin by triggering response systems which overprotect, much as breaking down muscles via exercise leaves you stronger. It's quite possible that very-small doses of BPA might protect people against the harm that might be done by larger doses. (If we had a large enough sample of comparable data points we could draw a response curve.) Here's a good paper which does that for a variety of substances. --Blogjack (talk) 21:31, 4 June 2009 (UTC)

Yilloslime has simply reverted the table. He ignores the discussion above, and simply reverts the article to being one-sided. there is a clear argument as to why you need the high dose studies. They contrast with the low dose studies, and they are the basis for government regulation in the USA, Europe and Japan. There is no reason whatsoever for removing these studies from this discussion of bisphenol. —Preceding unsigned comment added by 82.34.112.2 (talk) 01:04, 11 January 2009 (UTC)

As discussed above, it's not up to wikipedia editors to sift through the dozens of available toxicological studies and decide which ones are most relevant, and then highlight them by putting them in a table. That would violate WP:SYN. The only reason the table in its long standing form (i.e without the 2 studies the anon editor wants to include) is permissible is because someone else, a reliable third party source, put that table together. Specifically, CEHRH selected a list of studies which it deemed to be at least of moderate usefulness for assessing the risk of BPA to human reproduction, and then EWG selected studies from that list and featured them in a table. Later, that table was reprinted by a major newspaper (I forget which one, but it's discussed above.) The table we have in this article is a reproduction of that EWG table, minus a few studies that were removed to keep things from getting too long.

With regard to the industry studies that the anon-IP editor wants to include, I am not opposed to including a discussion of these studies in the article, especially since they have been touched on in numerous secondary sources, but they simply cannot be included in the table, as that would violate WP:SYN. Hope that makes sense. Yilloslime (t) 02:15, 11 January 2009 (UTC)

I personally think you misunderstand what is stated at WP:SYN. From the first sentence there: "Do not combine material from multiple sources to reach a conclusion not explicitly stated by any of the sources."

Last two sentences of WP:SYN: "Carefully summarizing or rephrasing source material without changing its meaning is not synthesis—it is good editing. Best practice is to write Wikipedia articles by taking material from different reliable sources on the topic and putting those claims on the page in your own words, with each claim attributable to a source that explicitly makes that claim."

Simply putting data into tables doesn't change its meaning. Breaking tables up into sub-tables doesn't change its meaning either (these are both merely format changes). A table is a way of summarizing meaning, and is used in many, many articles to summarize data (almost all lists here on wikipedia, and no few articles, are such "synthesized" tables).

The next time this comes up, if you still think a table or sub-tables would be original research of a sort, I suggest a WP:RFC. --Formerly the IP-Address 24.22.227.53 (talk) 07:56, 10 July 2009 (UTC)

Recommendations for improvement

The following suggestions were generated by a semi-automatic javascript program, and might not be applicable for the article in question.

• Please expand the lead to conform with guidelines at Wikipedia:Lead. The article should have an appropriate number of paragraphs as is shown on WP:LEAD, and should adequately summarize the article.^[?]
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• Per Wikipedia:Manual of Style (numbers), there should be a non-breaking space -   between a number and the unit of measurement. For example, instead of 50 µg, use 50 µg, which when you are editing the page, should look like: 50 µg.^[?]
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• As per Wikipedia:Manual of Style (dates), dates shouldn't use ^th; for example, instead of (if such appeared in the article) using January 30^th was a great day, use January 30 was a great day.^[?]
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You may wish to browse through User:AndyZ/Suggestions for further ideas. Thanks, Wim van Dorst (talk) 20:52, 9 June 2008 (UTC)

Regarding section of primate research

I'd initially installed a paragraph on research that shows BPA causes brain damage in primates. This research is very significant because it's been done on primates because it approximates the effect on humans - more so than rodents for example. It's a very important development in the debate on BPAs health effects, and there should be a paragraph to specifically cover this within the article. When the original paragraph that I installed on this topic was removed I was somewhat surprised. An addition or an edit maybe, but not a removal. The comment in the history re removal of the original primate res paragraph was:"moving stuff on primate study to new section". Where is it?

Wikipedia is an encyclopedic type information service that spells things out in a good lay fashion. Critical topical information should not buried. Please come in and justify this action if you wish to do that again. Thank you.John Moss (talk) 08:25, 6 September 2008 (UTC)

I'm not going to spend a lot of time digging, but it appears you might have been mistaken. It seems that your paragraph was not removed, it was edited and inserted somewhere else. With much better references, too, IMO. [9] --Rifleman 82 (talk) 11:24, 6 September 2008 (UTC)

Thanks Rifleman, I found it. I must be going blind. lol. Sorry about that Yilloslime. Cheers.John Moss (talk) 13:21, 6 September 2008 (UTC)

No worries! Yilloslime (t) 17:11, 6 September 2008 (UTC)

Cheers Yilloslime. Anybody have thoughts about the implications of this new primate research, on-top of the other studies showing endocrine disruption. Is this the final blow for BPA credibility? (if it had any left) John Moss (talk) 22:37, 6 September 2008 (UTC)

Well, John, this primate research has implications if you are a post-menopausal woman taking estrogen therapy while also injecting BPA into your veins. So I'm not very sure how totally relevent this research is. --Angryapathy (talk) 17:30, 9 October 2008 (UTC)

The NON-identification problem in plastics

There's a big question still unanswered in the section on identifying plastics using BPA: How does a consumer gauge the likely content of plastics where NO 1-7 designation is provided?

Common items that that have this ID problem: Household PVC piping (how commonly is this used for water piping?), and ubiquitous kitchen items, including hard coffee thermos linings that have no numerical label, coffee makers, coffee filter fittings, coffee pot lids and sealings/stoppers, plastic lunchbox linings, hard bottle caps for nutritional supplement/medication vials, plastic linings on metal food cans or on metal lids to glass-bottled drinks, and so on. Can someone add more guidance on plastics composition of unlabeled consumer products, please?

Also, can anyone provide the website for a database of tests of product packaging for BPA?

For example, I've just noticed a bottle of ACT flouride comes in a #3 container -- flouride is acidic and it seems likely to induce leaching. Also perturbing, a tub of "all natural" hummus has been packaged in #7 plastic. Most of these murky instances are ones that an outside source would have to investigate the composition of, if there is no legal obligation among producers to supply it.

Can anyone identify any Congressional bills that propose requiring plastics suppliers to label the makeup of these suspect plastics categories?A.k.a. (talk) 22:40, 16 September 2008 (UTC)

The problem is, WP does not give medical advice, and WP is not a how-to guide. I think the article already says what needs to be said on this topic. But to answer your question, there really no way, other than the voluntary 1-7 labeling system, to know whether a product might contain BP. Yilloslime (t) 03:47, 17 September 2008 (UTC)

WAIT! WEIGHT!

Sorry for the totally cheesy pun of a section header, but anyways: A.k.a. you're doing great work here, but I also think you are going a little overboard. You've added about 9Kb of new material, and it's almost entirely about the new JAMA study and accompanying editorial. And while I agree that this a very important new study, 9Kb is just way more WP:WEIGHT than it deserves--almost a fifth of the article is devoted to it now. I think this needs to be pared down quite a bit. Yilloslime (t) 04:57, 17 September 2008 (UTC)

I just trimmed about 6Kb out, and I think it's an improvement. I returned the Human Exposure section back to how it was prior to Sept 16, and made a new section on the Lang study. Then I tried to incorporate the criticism and praise for it into the Government and Industry response section. It's definitely a challenge trying to organize this article. I've tried to keep all the info on health effects--including scientific studies and risk assessments by gov't agencies--in one section, and all the politics in another. But that's kinda hard b/c what's happening in politics is largely a reaction to the studies and assessments. It would be easier to write the article chronologically: this study came out, then this hearing happened, then this agency finalized it's risk assessment, then this politician said... But that would get tedious to read. So if anyone has any ideas for improving the organization of this article, please, let's hear them! Yilloslime (t) 07:20, 17 September 2008 (UTC)

I think the article should be pared down to the basics, with references/links to major reviews (e.g. NTP, Health Canada, etc.) for more information - this is after all meant to be an encyclopedia-type article, not a major technical report. I don't see a lot of value in describing all the individual studies, especially since both the chemical industry and environmental groups have done some pretty poorly designed studies basically designed to reach a specific conclusion, and the average layperson doesn't have the background to distinguish the good science from the bad (even experts can't always tell from the publications). Instead, maybe just briefly listing the known effects in humans/animals (based on the conclusions of the major reviews), then stating "some other studies have also suggested links with...(other possible effects)". Also, maybe some of the government/industry response could be summarized in more of a point form or table format to make it a bit more readable.Ashartus (talk) 14:56, 17 September 2008 (UTC)

Everyguys, I'm all for these edits. I very much appreciate the patient tone you took re my own contributions, and appreciate even more that you've revisited the article so quickly after the JAMA study broke. I'm low on the totem pole of contributors, and new, so will improve with time. Please bear in mind that some fraction of the bloat here is the conundrum every peon faces: Should I actually delete anything a previous contributor might have left in that could be deemed obsolete? For reputation's sake, best to let the project managers make the cuts. A.k.a. (talk) 03:19, 19 September 2008 (UTC)

3 Million Tons?

http://jama.ama-assn.org/cgi/content/full/300/11/1303 says 2003 production was 2 million, 6-10% growth anually. Someone please fix 132.198.84.83 (talk) 12:48, 17 September 2008 (UTC)

BPA in PVC plumbing?

This article states that BPA is used in PVC to prevent polymerization. Now, there are many grades of PVC, from soft to hard. Shall I presume that soft contains a fair amount of BPA, and hard contains very little? Typical indoor plumbing PVC is yellow and hard; white PVC is softer, and not rated for indoor/hot-water use, but is often used in water supply mains running to the house. So the question is: how much BPA do these two common types of plumbing contain, and how much might leech into the water? linas (talk) 01:36, 22 September 2008 (UTC)

New credible study from Environmental Health Perspectives

This study should be integrated in the article."Exposure to Bisphenol A Prenatally or in Adulthood Promotes TH2 Cytokine Production Associated with Reduction of CD4+CD25+ Regulatory T Cells" [10].

The study showed that BPA promotes the development of Th2 cells in adulthood, and both Th1 and Th2 cells in prenatal stages, by reducing the number of regulatory T cells. This could have a profound effect on your health as Th1 and Th2 are the two “attack modes” of your immune system. Based on the type of invader, your immune system activates either Th1 or Th2 cells to get rid of the pathogen. Th1 (T Helper 1) attacks organisms that get inside your cells, whereas Th2 (T Helper 2) goes after extracellular pathogens; organisms that are found outside the cells in your blood and other body fluids. When your Th2 are over-activated, your immune system will over-respond to toxins, allergens, normal bacteria and parasites, and under-respond to viruses, yeast, cancer, and intracellular bacteria, because as one system activates, the other is blocked. MaxPont (talk) 16:33, 11 October 2008 (UTC)

I'm not sure that we need mention this study. There have been literally hundreds of in vitro and in vivo studies of BPA, we can't talk about every one of them. The article currently focuses on risk assessments and consensus statements (secondary/tertiary sources) and only mentions a handful of primary sources. One is the first and only epidemiological study of BPA exposure and another is a recent monkey study--both are far more relevant (and have received far more attention) than this rat study in EHP. The other primary sources are mostly rat studies and they are cited as illustrative examples of the numerous low dose toxicological studies that have been conducted. So I don't see how adding this improves the article. If we do mention it, we can't go into all this detail about Th1/2 cells. Perhaps something like, "BPA exposure in rats has been linked immunosuppression[cite]" if that's an accurate summary. Yilloslime (t) 20:56, 11 October 2008 (UTC)

Bisphenol and the metric system

The recent change from milligrams to micrograms was, I believe, based on faulty arithmetic. The edit summary stated, "3250 mg/kg = 3.25 kg/kg... this doesn't make sense... if one had to ingest 3.25x their own weight, there would be no issue with this substance. µg is the proper measure". But 3250 mg doesn't equal 3.25 kg; it equals 3.25 grams, a milligram being 1/1000 of a gram and a kilogram being 1000 grams. It is entirely possible that my holiday-addled brain is messing this up, but I don't think so, so I'm reverting it. (3.25 grams = 0.115 oz., btw, fwiw.) Rivertorch (talk) 15:03, 26 December 2008 (UTC)

Split proposal

I have added a {{splitsection}} tag to the health effects section. This section is a large portion of the article and therefore should be split out. Some editors may be concerned about content forking to push a POV but I do not see this as a valid reason for not carrying out a split. There are many WP articles that are largely critical in their content eg. Pollution in the United States, Criticism of religion, Health effects of tobacco etc. -- Alan Liefting (talk) - 21:06, 21 March 2009 (UTC)

I disagree, the article would look like a stub otherwise. Also, moving the information would shadow it.--Nutriveg (talk) 18:15, 22 March 2009 (UTC)

There is potential for two seperate articles here: Bisphenol A and Health issues with bisphenol A (or such-like). At present it is almost an article on the later! If the new article was split out with the Bisphenol A article becoming a stub then this is not a fault of the split. -- Alan Liefting (talk) - 10:00, 27 March 2009 (UTC)

I can't see why a split is necessary. This seems to be an integral part of a not-particularly-long article, and as Nutriveg says, removing it would leave rather a short article. Alan, could you explain more of your reasoning please? Richard New Forest (talk) 18:39, 22 March 2009 (UTC)

My reasoning for the split is not so much the length of the article but the fact that there are two separate articles here with one topic overshadowing the other. -- Alan Liefting (talk) - 10:00, 27 March 2009 (UTC)

Also disagree. What makes more sense is to section off "Human exposure to bisphenol A" and "Government and industry response" out from under the overburdened and misleading health effects section. Just because people are exposed, doesn't mean there is a health effect. Also, how government and industry respond to toxicological/epidemiological data isn't a "Health effect" either. I'm going to be BOLD and make those changes, and remove the split proposal, because these minor organizational changes will efficiently eliminate the concerns leading to the proposal (sheer length). -Shootbamboo (talk) 19:28, 22 March 2009 (UTC)

Can you explain what you mean by "section[ing] off"? -- Alan Liefting (talk) - 10:00, 27 March 2009 (UTC)

I also don't see what's to be gained by splitting. There was brief exchange on my talkpage on this topic about a month ago, which I think might be informative:

Hey Yilloslime, I've noticed that you've been fairly active in trying to keep this article under control. As alluded to by yourself and Smokefoot, the article has become swamped with BPA controversy. Between the average concerned editor and the usual array of scaremongering fruitloops, the info about the compound itself seems fairly minor in comparison. Is it about time to split this into two, namely bisphenol A and bisphenol A poisoning, or similar? Cheers, Freestyle-69 (talk) 03:28, 22 February 2009 (UTC)

I agree the article is in need being updated, reworked, and trimmed, though I don't think I've got the time (or motivation) to do it, at least right now. W/r/t to splitting, I'm generally opposed to splitting out "controversy" articles, though there are certainly times when it is warranted. I mainly worry that the controversy article becomes a POV fork/playground for editors with an axe to grind. I also think we do a disservice to our readers when we stuff highly sought after content into sub articles. In other words, most people visiting Bisphenol A are probably more interested in its health effects and the recent controversy than they are about it's physical properties and chemical reactions. Therefore it seems to me that the former should be covered in Bisphenol A and the latter could be covered in Chemistry of bisphenol A or something like that, if we do split the article. But as I said already, I'm not sure that splitting is in necessary at this point. That's my 2¢; I'm often in the minority when it comes to split-proposals, though. Yilloslime 01:29, 23 February 2009 (UTC)

Yeah, fair call- I take your point about the general public and why they would hit the article. No biggie either way. Cheers Freestyle-69 (talk) 21:37, 23 February 2009 (UTC)

Also, with 18kb of readable prose, the article is not unreasonably long, and, per Wikipedia:SIZE#A_rule_of_thumb, for articles of this size "Length alone does not justify division". Yilloslime ^T_C 20:00, 22 March 2009 (UTC)

As mentioned above, I see a need for the split based on the two distinct topics within the article rather than the length of the article itself. -- Alan Liefting (talk) - 10:00, 27 March 2009 (UTC)

Can't really see the two topics. The substance and its effects – why is that two topics not one? Richard New Forest (talk) 21:23, 27 March 2009 (UTC)

That is the two topics - the substance and its effects. They can be two standalone and complimentary articles. -- Alan Liefting (talk) - 23:58, 27 March 2009 (UTC)

Yes, it would pe possible to split them – but why? I can't see that any serious case has yet been made for a split: "because we can" seems to be the only reason, and it is not a good enough one on its own. Richard New Forest (talk) 16:05, 28 March 2009 (UTC)

[rm indent] My reason for suggesting the split is:

• there are two separate topics with one being a large portion of the article and therefore giving it an unbalanced structure
• having two separate articles makes linking and categorisation easier
• encyclopedias traditionally consist of many short articles This makes it easier to find info. Also, in this day and age with info overload, short concentration span and the need for instant gratification it makes sense to have an easily digested and locatable article. -- Alan Liefting (talk) - 19:20, 28 March 2009 (UTC)

Still no substantive reason I can see... It still looks like one subject, one article, and I think it would only need splitting if it became so long as to be unwieldy. Richard New Forest (talk) 19:28, 28 March 2009 (UTC)

Also, as per notability guidelines, a new article is justified. Collectively all the reasons that I have given are grounds for a separate article. Article length is not the only reason to split an article. -- Alan Liefting (talk) - 21:46, 28 March 2009 (UTC)

I agree with Alan that these could be separate articles. Notability requirements easily would be met for either topic, and if either were subjected to AfD then I'm sure they'd survive. Having said that, nothing requires us to split them, the current article is not overly wrong, and I think the topics are best treated together (for now at least). Yilloslime ^T_C 22:01, 28 March 2009 (UTC)

Oppose split. The article isn't overly long. (Btw, there are "fruitloops"—nice term, that—on both sides of the equation.) Rivertorch (talk) 03:41, 23 March 2009 (UTC)

On reflection of the reasons put forward, I oppose the split too. Like I said, no biggie either way, but I am concerned about the way it's all coming across. Since I've opened my trap I'm happy to help if given some direction. And... yeah, we have a few words over here to describe the odd people, whichever side they're on :) Freestyle-69 (talk)

I say we follow the lead of the asbestos article and do not split. I think that article should be a good template for the issues going on here since health problems with asbestos have been going on for decades longer than the recent developments with BPA. Angryapathy (talk) 12:09, 27 March 2009 (UTC)

The asbestos article has had no discussion on whether it should be split or not. Therefore the status quo is no indication of whether it is the preferred option. -- Alan Liefting (talk) - 23:58, 27 March 2009 (UTC)

Second split proposal

The "Government and industry response" section should be split out. As the article currently stands it is more of a "Government and industry response" article rather than an article about a chemical. I have also suggested splitting out an article called Bisphenol A in the United States to avoid systemic bias. -- Alan Liefting (talk) - 01:28, 31 July 2009 (UTC)

I disagree, spliting US would break NPOV since much of recent response to BPA has happened in the US.--Nutriveg (talk) 15:22, 31 July 2009 (UTC)

It will not be POV if a summary is left behind. -- Alan Liefting (talk) - 19:49, 31 July 2009 (UTC)

It would unbalance yet the new article since most controversy is removed or summarized. The leftover would be stub.--Nutriveg (talk) 21:47, 31 July 2009 (UTC)

I also disagree with splitting the "Government and industry response" section, since its most a response to the recent studies cited on the top of the article and would look meaningless if split. The remaining of the article is still small to be left alone.--Nutriveg (talk) 15:36, 31 July 2009 (UTC)

A summary would be left at this article of course. Whether the article is "small" or not after a potential split is subjective. A small article can be expanded. Alos there are a number of advantages in two small articles over one larger one. Given the media coverage and community interest in the health and policy issues means that an article should be written. -- Alan Liefting (talk) - 19:49, 31 July 2009 (UTC)

I don't see the need for a split, I see the need for some article trimming/consolidation, which has been in progress, thanks Nutriveg. As a comment, I think it's an awkwardly worded title (government and industry) because it begs the question, why not academics (or others)? -Shootbamboo (talk) 21:38, 31 July 2009 (UTC)

I don't see the health studies and public response to them as subject of split. Shootbamboo, most of the response has been from governments/indutry but one can rename it to "Public response" if will--Nutriveg (talk) 21:47, 31 July 2009 (UTC)

I should have been clearer, I was talking about a theoretical stand-alone article. -Shootbamboo (talk) 22:45, 31 July 2009 (UTC)

Reclcyling codes are not useful

The article tries to relate the broad plastic recycling codes to identification of BPA: This is false. The attempted logic seems to be: 1) BPA in plastics sometimes can be a problem, 2) Some polycarbonates use BPA, 3) Recycling Group 7 includes polycarbonates (among MANY other plastics and combinations), therefore 4) Recycling group 7 recycling codes are a health warning to us. This is very false logic. Recycling codes are for recycling only. Rlsheehan (talk) 16:47, 2 August 2009 (UTC)

It sounds like you just don't like it; I am not sure what improvements to the article you are suggesting. The article is clear — only some #7 plastics are PC. -Shootbamboo (talk) 17:00, 2 August 2009 (UTC)

It's a good form to identify at least by exclusion (not PETE, not PS, ...). If you are aware of any plastic bottles that are #7 but not PC, and have a form to identify them please add that information.--Nutriveg (talk) 17:34, 2 August 2009 (UTC)

some sources for recycling codes

These two articles both claim that #1, #2, #4 & #5 are BPA free. I couldn't find much in the way of claims about #6. Maybe someone can add these references? Thanks.

• http://www.washingtonpost.com/wp-dyn/content/article/2008/04/15/AR2008041502161.html
• http://www.usatoday.com/news/health/bpa.htm

Ozy42 (talk) 19:41, 27 August 2009 (UTC)

2009 research section

I was bold in tidying to make it appear more like the 2008 section, in order to reduce what I saw as unscientific non-WP:NPOV and WP:RECENTISM and WP:UNDUE weight on WP:PRIMARY sources. -Shootbamboo (talk) 04:30, 6 September 2009 (UTC)

I just looked at your first edit [11] where you removed a referenced section, that was valid by the provided access date, and I tried to revert it but couldn't because you made several edits on top of each other. So I'm bold reverting the article to the stable version previous of your massive unorganized edits.--Nutriveg (talk) 03:15, 7 September 2009 (UTC)

I reviewed your other individual edits and re added those I found relevant, please discuss the others in the talk page before including them again.--Nutriveg (talk) 03:52, 7 September 2009 (UTC)

My edits

I organized the health effects section by mechanism of action, types of effects and exposure levels, rather than a miscellaneous dump of any related studies into the 2009 section. Obviously historical studies were moved to a separate history section for the interested. I found no place for sentences xxx expressed concerns about bisphenol A without further specification, and I doubt they are of significant value, although being referenced. Mikael Häggström (talk) 18:47, 1 October 2009 (UTC)

Thanks for being bold but I would separate reviews from other studies, I'm undoing your edits.--Nutriveg (talk) 18:51, 1 October 2009 (UTC)

We can surely organize by effects and highlighting reviews from individual studies. Indeed, every section as it is now should have a separate review section. I showed how, including your last edit. Surely it's not perfect, but I think it is much better than it was before when any study could just be dumped into the article without further sorting. I think we'll force future edits to be more organized, for instance, having to include more reviews. Mikael Häggström (talk) 19:16, 1 October 2009 (UTC)

If there isn't a significant number of secondary sources you can separate health issues under the research section, but not in the main section, giving WP:DUE balance to those issues. Don't forget to point the year and kind of study when you move those around.--Nutriveg (talk) 19:27, 1 October 2009 (UTC)

Good points, I'll do that. I'll keep that revision separate from reviews and add dates where needed. Mechanism of action and exposure levels could still be separate sections. Mikael Häggström (talk) 19:59, 1 October 2009 (UTC)

Also, when we've reached a version we are both happy with, the Human exposure section below should also be merged with Health effects.Mikael Häggström (talk) 20:02, 1 October 2009 (UTC)

That "Mechanism of action" section is awful, just a bunch of poorly cited phrases from unreliable sources. This it not a medical article but take a look on WP:MEDRS to get aware of how to cite medical sources.--Nutriveg (talk) 20:28, 1 October 2009 (UTC)

Surely, at least the newspaper-cited one can be excluded. Mikael Häggström (talk) 20:39, 1 October 2009 (UTC)

The source shouldn't be excluded but the original source cited and context added, you are stating those claims as they were well accepted, not a result of some study.--Nutriveg (talk) 20:48, 1 October 2009 (UTC)

You also eliminated dosages and overall context, that are very important issues.--Nutriveg (talk) 20:48, 1 October 2009 (UTC)

I made a separate section for exposure levels without any direct association to a specific effect that could sorted elsewhere [12]. If you mean the first lines under the Health effects header as overall context, I agree there should be some kind of introductory text, and the one you added is just fine. However, I doubt Previous studies give much additional information, since I sorted that same text into specific effects where there was a specific effect. However, I don't see any direct harm of having it, as long as it doesn't start to be randomly expanded by any previous studies. Yet, studies are much more useful in what they've indicated rather than when they were carried out.Mikael Häggström (talk) 05:58, 2 October 2009 (UTC)

The consensus of the section named "Previous studies", but could be named something else, is not about a specific effect, and that section citations need to be contextualized in time since they were made when most of the article cited articles weren't available for analysis.--Nutriveg (talk) 11:27, 2 October 2009 (UTC)

It seems they may almost be moved to the historical studies (and statements), but it's no big deal. Anyhow, I think it's a great improvement with the reviews you added, and that readers now easily can read about e.g. thyroid effects without having to take history classes. Mikael Häggström (talk) 13:57, 2 October 2009 (UTC)

What does difunctional mean?

The second sentence says "It is a difunctional building block..." I think "difunctional" is a rather obscure word to put in the introduction without explanation. I'd guess that it means it has two functional groups, but I'm not sure. Billgordon1099 (talk) 05:14, 9 November 2009 (UTC)

"bifunctional" may be a better word. 129.42.184.35 (talk) 18:28, 11 November 2009 (UTC)

Style

This article has adopted a style of "a 2007 review states X" instead of just stating X. I understand that this could occasionally be useful, but I find this repeated "review" and "study" wording distracting and poor in style. If we are presenting an overview on the toxicity of BPA for the thyroid gland, for example, I would assume this statement is being pulled from a review itself or a review section of an original research article. Also, these contextual frames are not in the text itself. A 2007 review does not begin with "This 2007 review..." A minor point but still, I find this distracting and senseless when applied en masse. Comments? -Shootbamboo (talk) 23:27, 14 November 2009 (UTC)

It might be necessary to use this style on Wikipedia. If we're talking about interpretations and general conclusions rather than basic primary science (in which the date is less important - a study of a mouse is the same regardless of date), the date of the information is very important, and I don't necessarily always want to have to click the footnote to find it out. Also, although there are no doubt many who disagree with me, in science clarity and information trump style. The current style might be overkill - and unfortunately when you say "a 2009 review", you don't identify it uniquely. So referencing it again can get confusing.

Over at water fluoridation, Eubulides dealt with the reviews by simply reporting a lot conclusions as if they were factual (not really attributed). This can be somewhat misleading but reads a bit better. Controversial uncertain facts should be attributed, but others can be stated as facts. II | (t - c) 00:52, 15 November 2009 (UTC)

Paper

This edit incorporated a study as a reference in such a way that does not verify the sentence. Rather, it appears to be a synthesis which advances a position as the study measured effluents and states "Bisphenol A...is believed to have originated from waste containing thermal paper and/or other printed paper" (p. 978). WP:V and WP:OR are (is a) core polic(y). This is a problem I hope does exist elsewhere in the article... I discussed the problems with this content here also. -Shootbamboo (talk) 00:02, 15 November 2009 (UTC)

The information is supported by the source, on the other hand you saying that "BPA is used to produce paper", completely misrepresents such use, since BPA is used to for the printing purpose of papers that don't need an external source of ink. In that same edit you removed a valid reference, maybe to justify the exclusion of the term "high concentration". I'm reverting that your edit.--Nutriveg (talk) 12:05, 16 November 2009 (UTC)

Where in Fukazawa does it verify that "BPA is found in high concentration in thermal paper and carbonless copy paper"? I read that it was "high" in effluents... but where do you get "high in paper" from? I did not remove any reference, they are all here [13]. -Shootbamboo (talk) 21:35, 16 November 2009 (UTC)

That source you cite is out of context, there are other sources clearly supporting the information: "Thermal paper (...) due to its extremely high BPA content". You may not have completely removed the source but you moved it to another place to isolate it from other sources supporting the information. I'm reverting your edits.--Nutriveg (talk) 12:30, 17 November 2009 (UTC)

Why do you repeatedly cite a source that, by your own admission, does not verify the sentence you construct? Why do you remove mention of the use of BPA in thermal and copy paper? "High" and "extemely high" are unnecessarily vague, in the opinion of the MOS (and mine). (I don't follow your statement that I cited something out of context.) -Shootbamboo (talk) 04:10, 27 November 2009 (UTC)

I don't know what you're talking about, there isn't a single source supporting the statement as you're trying to make it and the source I provided above is already cited. "Use in production" is vague, since it implies it may not present in the product itself or it doesn't represent a form of contamination. The sources supersede your opinion.--Nutriveg (talk) 11:01, 27 November 2009 (UTC)

(Outdent)—to clarify, I will list my concerns (and concessions) I have regarding your most recent revert concerning BPA and paper. (You did not most recently revert me saying "use in production", however.)

• It seems inappropriate to cite doi:10.1016/S0045-6535(00)00507-5 (Fukazawa) behind the sentence "BPA is found in high concentration in thermal paper and carbonless copy paper" as Fukazawa does not WP:V this.
• It appears to be poor judgment to remove the sentence "BPA is used in the color developing layers of thermal paper and carbonless copy paper" because the sentence is under the "Use" section. I think it is best to explain that BPA is a key constituent in the color developing layer of the paper itself. Your revert left no detail on why BPA is used.
• The Society for Science and the Public news source describes the levels as "high" in carbonless copy paper, but this is based on unpublished data, making it problematic.
• To concede, The WIT Press publication did not equivocate on the issue for "extremely high" levels in thermal paper, so I think including it would be fine. If an accurate value is out there, however, it does make it unnecessarily vague. -Shootbamboo (talk) 19:52, 28 November 2009 (UTC)

The source is appropriate because its on topic, and referenced by other authors. It's not a singe source supporting that phrase it just adds to the others.

I moved it to a more appropriate section, since most sources talk about exposure, if you think a relevant amount of the Bisphenol production is used to produce those kind of papers please add something about that in the "Use section".

There's nothing problematic, the information is supported by reliable sources, there's no need to use specific sources.

Both sources use the "high" term, I don't see any source agreeing in a single value and how that would be accurate or more understandable by the reader.--Nutriveg (talk) 20:35, 29 November 2009 (UTC)

• As it doesn't support the phrase, it shouldn't be included, in my opinion. I find it misleading. I am going to remove as a source for that sentence.
• Moving down there (minus Fukazawa!) is fine with me. However, reverting/removing my mention of the Use of BPA with these sources shows poor judgment, in my opinion.
• The source admits the researchers' findings are unpublished. I find this problematic.
• A value is intrinsically more accurate than a descriptor. I have attempted to contextualize this for the reader multiple times in contrast to polycarbonate water bottles, but you revert here and at carbonless copy paper. -Shootbamboo (talk) 15:58, 26 December 2009 (UTC)

• It's a additional source supporting the information and cited by other scientific sources in that sense, so it's relevant and should stay.
• As you said we're talking about different things: exposure and use. I'll revert your edits if I find them problematic.
• As I said the information is supported by different sources, not a single one and they follow Wikipedia requisites for this particular kind of article.
• That doesn't justify original research.--Nutriveg (talk) 20:03, 26 December 2009 (UTC)

BTW, this citation you made, is about how a source should be cited, not about which references should be included.--Nutriveg (talk) 20:11, 26 December 2009 (UTC)

• I disagree, and don't get your BTW, feel free to elaborate on my talk page. (I'm not going to ask others for input because I don't think it would be a good use of others' time, but I find it a misleading and inappropriate citation still.)
• Well what's there now is remarkably similar to what I've written previously but was reverted...
• I'm skeptical.
• I disagree that what I did with the news source was OR... -Shootbamboo (talk) 22:00, 26 December 2009 (UTC)

• I'm not going to move the discussion to anyone's talk page, please point what you didn't understand.
• So what's the problem?
• What counts here are the sources not your personal views.
• I've said enough about that in Talk:Carbonless copy paper#OR.--Nutriveg (talk) 22:13, 26 December 2009 (UTC)

Outdated?

I replaced a 1998 external link with a 2008 one here but it was removed here as being "outdated". Considering the lead states "in 2008 after several governments issued reports questioning its safety..." I can't imagine how adding context to the 2008 NTP conclusion of "some concern" would be "outdated". -Shootbamboo (talk) 23:47, 16 November 2009 (UTC)

I removed both. It's outdated since most relevant studies were published after that date (29 April 2008).--Nutriveg (talk) 12:33, 17 November 2009 (UTC)

That appears to be your opinion, but can I see that in a reliable source? Until then I disagree. -Shootbamboo (talk) 03:55, 27 November 2009 (UTC)

The article content is a good start, for example the Lang study that triggered most of the response documented in the "Government and industry response" is September 2008. Certainly outdated.--Nutriveg (talk) 10:49, 27 November 2009 (UTC)

Wikipedia is not a reliable source for Wikipedia. See WP:CIRCULAR. Can you provide a WP:RS that states "most relevant studies were published after 29 April 2008" please? -Shootbamboo (talk) 17:43, 28 November 2009 (UTC)

Even if you found an source that showed the NTP Panel agreed with you that its own assessment was "outdated" I would still argue that there is historical value of understanding where the science was then, and what drove their thinking. I think our readers can understand that some of our sources have been published after 29 April 2008. The source also helps puts the lead in context as I mentioned in my edit summary. -Shootbamboo (talk) 18:02, 28 November 2009 (UTC)

That section is properly referenced. I'm reverting your edit.--Nutriveg (talk) 20:12, 29 November 2009 (UTC)

How is that "That section is properly referenced" a WP:ELNO? The source is a discussion from an academic in the low-dose field, another academic, a representative from industry, a Health Canada minister, and the associate director of the NTP—giving context to the 300+ page 2008 NTP report. The source provides a media rich (radio with no transcript) neutral perspective with lots of context for a big BPA publication, in my opinion. In your edit summary you asked I please not add the source; I had indicated I thought discussion should take place. Your discussion is lacking, in my opinion. The consistent reverts make me wonder if you think you WP:OWN the article. I'm going to restore the EL. Furthermore, I do not see how your "outdated" rationale would apply to other pre-April 2008 sources. -Shootbamboo (talk) 00:51, 30 November 2009 (UTC)

You said that section is a circular source, that section content is properly referenced where the actual sources are available. As I said many times most of the public response was motivated by studies published after 29 April 2008 and most studies in the "Health effects" were later published as well. So the link you're trying to add is outdated. You're the one trying to add that content so you're the one that need to get agreement before adding that content, and so far you didn't get it so stop readding it.--Nutriveg (talk) 10:41, 30 November 2009 (UTC)

I don't think we understanding each other well. This may help: Wikipedia:Don't revert due to "no consensus". -Shootbamboo (talk) 16:05, 26 December 2009 (UTC)

This is an essay, the same way "the status quo reigns until a consensus is established to make a change", you're the one trying to make changes, you're the one re adding that link.--Nutriveg (talk) 19:41, 26 December 2009 (UTC)

I wouldn't take an EL section that seriously...Other external links would be "outdated" by your logic, as far as I understand it. Yet those remain. Your opinion that it is outdated is not supported by WP:RS and is not a WP:ELNO. I see no logic to exclude it. -Shootbamboo (talk) 21:33, 26 December 2009 (UTC)

My opinion may apply to others external links in the same situation, the information is outdated, so "factually inaccurate".--Nutriveg (talk) 21:41, 26 December 2009 (UTC)

That's silly. -Shootbamboo (talk) 21:53, 26 December 2009 (UTC)

Top Scientific Breakthroughs of 2009

Wired have released a list of the top science breakthroughs of 2009, listing at number 5: No. 5 Bisphenol A in Plastics Harms Humans.

“ For years, the plastic additive Bisphenol A was the center of a bitter environmental health battle. Researchers pointed to studies showing that its estrogen-mimicking qualities caused cancer and developmental damage in laboratory animals, and might do the same in people. Plastic manufacturers said animal tests were no substitute for human studies, which didn’t exist. The U.S. public — of whom 90 percent have detectable levels of BPA in their bodies — was caught in the crossfire.

In November, epidemiologists produced a study of BPA in humans. In 164 male Chinese factory workers exposed to high levels of BPA, severe sexual dysfunction was rampant. Their exposures were far higher than most people, but it can no longer be argued that BPA affects only lab animals, not people.

”

78.105.234.140 (talk) 15:48, 2 January 2010 (UTC)

Conclusions of follow up study on cardiovascular disease

The reference concluded diet and survivability could theoretically account for the observation. How then is it an "extrapolation"? -Shootbamboo (talk) 19:50, 17 January 2010 (UTC)

You should focus on the conclusion of the article, not the discussion section which included phrases such "would strengthen the evidence for BPA playing a causal role" that likewise look unappropriated.--Nutriveg (talk) 02:11, 18 January 2010 (UTC)

efficient and only byproduct is water? LOLOL

The reference material actually says:

Bisphenol A. There are many processes for the industrial synthesis of this most important bisphenol [362], [372-376]. Currently, hydrogen chloride or sulfonated cross-linked polystyrenes [372], [377-379] are used as the catalyst which are usually arranged as a fixed bed over which the reaction mixture is passed (Fig. 2). The reaction of phenol with acetone takes place at 50 – 90 °C, the molar ratio phenol – acetone is up to 15 : 1. Bisphenol A crystallizes as an adduct with 1 mol phenol, after separation of the hydrogen chloride by distillation or neutralization. The use of ion exchangers is preferred to that of hydrogen chloride because they are less corrosive. The yield is normally 80 –95 %. Figure Figure 2. Flowchart of a bisphenol A plant according to [383] a) Storage tank; b) Reactor; c) Column; d) Crystallizer; e) Separator; f ) Melt; g) Desorber; h) Flaking off To isolate the bisphenol, the whole reaction mixture can be fractionally distilled, whereby bisphenol A itself is distilled over particularly carefully under high vacuum, separated from resinous byproducts, and subsequently recrystallized under pressure at elevated temperature [380]. Crude bisphenol A can also be purified by extracting into hot heptane or mixtures of aromatics [381] or by recrystallization from aromatics [382]. A very high purity product with polyester quality is obtained if the bisphenol A – phenol 1 : 1 adduct is separated, recrystallized from phenol, and the phenol removed by distillation [375], [383]. These processes are mostly carried out continuously [372], [374], [376], [380], [383].

Essentially, the reference material says that BPA synthesis produces LOTS of byproducts (A resiny mess, in fact.. probably what that oozy stuff behind the polycarbonate factory is made of, huh?) and that distillation is required - either of the BPA itself under high vacuum (INEFFICIENT!) or by boiling off the phenol (and recapturing it). In the context of the original sentence, it appears the claim of "efficient" suggested that the reaction was neat, with no byproducts, as if the ketone and alcohol molecules just stuck together in only the prescribed arrangement, coming together with just enough force to expel the generated water molecules... but the reference text does not suggest industry operates with a catalyst that performs in such a manner (if it even exists). Zaphraud (talk) 06:30, 29 May 2010 (UTC)

References

Something around reference #98 makes all the references appear as bullets (instead of having numbers) thereafter. -Shootbamboo (talk) 15:27, 31 May 2010 (UTC)

How about getting rid of most of the primary sources?

This article seems to have a ton of primary sources (references to journal research papers) and reads like a survey of the research literature. However, WP:MEDRS says, "In general, medical information in Wikipedia articles should be based upon published, reliable secondary sources whenever possible. Reliable primary sources may occasionally be used with care, but there remains potential for misuse." I think the article would be of higher quality if most of the primary sources were removed and replaced by secondary sources (overview and review articles), and the article brought into compliance with WP:MEDRS. Billgordon1099 (talk) 05:35, 13 June 2010 (UTC)

Inaccurate introduction

The 2nd paragraph begins "Suspected of being hazardous to humans since the 1930s[citation needed]......" This is not accurate. I have yet to find a reference that supports this notion. Apparently the potential for estrogenic effects was indicated in the 1930's but not necessarily as a hazard to humanhs. An indication that it might be hazardous, especially at low doses (but still not in humans), wasn't discovered until 1993, when D. Feldman, et al, at Stanford University published an article about effects of trace BPA leaching from polycarbonate in Endocrinology, Vol 132, 2279-2286, 1993. 67.180.70.83 (talk) 06:21, 5 July 2010 (UTC)