Wikipedia:Featured article candidates/Water fluoridation/archive2

The following is an archived discussion of a featured article nomination. Please do not modify it. Subsequent comments should be made on the article's talk page or in Wikipedia talk:Featured article candidates. No further edits should be made to this page.

The article was promoted by SandyGeorgia 22:24, 6 June 2009 [1].

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Water fluoridation

Nominator(s): Eubulides (talk) 23:25, 27 May 2009 (UTC)

• Featured article candidates/Water fluoridation/archive1
• Featured article candidates/Water fluoridation/archive2

This became a Good Article after a careful and helpful review from Doc James along with critical and ultimately supportive comments by II. It went through peer review with positive comments by Finetooth and a useful quick comment from Colin. Its first attempt at FA status did not reach consensus, but elicited comments from Xasodfuih, Peripitus, and Mattisse, all of which I've tried to address in edits since then.

Fluoridation is sometimes controversial. The article focuses on technical aspects and briefly summarizes the controversy in its Ethics and politics section, with a subarticle Opposition to water fluoridation (not part of this nomination) that goes into more detail. Eubulides (talk) 23:25, 27 May 2009 (UTC)

How about an image of severe dental fluorosis to contrast with the mild one?--Doc James (talk · contribs · email) 03:51, 28 May 2009 (UTC)

That wouldn't be appropriate, as this article is about water fluoridation (the controlled addition of fluoride to a public water supply to reduce tooth decay), and water fluoridation does not cause severe dental fluorosis. A good image of a severe case would be appropriate for Dental fluorosis article, though, if such an image could be found. Eubulides (talk) 04:49, 28 May 2009 (UTC)

This paper says the rate has been found to be 0.3 and 0.6% in some studies. Now that we are getting fluoride from multiple sources this is becoming more of a concern.

And this one says "Chi-square tests showed a strong association between fluoride levels in well drinking water and severity fiuorosis of tooth #11 (/'<0.001). However, 16.1 % of the children exposed to 0.50-0.79 ppm F were free of dental fluorosis while about 24%) had severe dental fluorosis with pitting (TFI score a5)." Dental fluorosis in 12-15-year-old rural children exposed to fluorides from well drinkin water in the Hail region of Saudi Arabia Source: Community dentistry and oral epidemiolo [0301-5661] Akpata yr:1997vol:25 iss:4 pg:324

So I think this needs to be discussed in greater detail. Some areas have high natural levels of fluoride, some get fluoride from multiple sources, and sometimes the fluoridation equipment breaks down. Just saying that anything other than mild fluorosis does not occur from water fluoridation is a bit dishonest. Even though of course the risks of severe fluorisis is very small.--Doc James (talk · contribs · email) 15:26, 28 May 2009 (UTC)

I'm struggling to find sources that give a rate of severe fluorosis due to artificial water fluoridation. I see some population studies, but it isn't clear they tell us anything about water fluoridation. At present, I don't see how we can judge whether "severe fluorosis" needs to be mentioned in this article at all, let alone have a picture of it. Colin°^Talk 17:04, 28 May 2009 (UTC)

This paper is the best I can find. There is a chart comparing various degrees of fluorosis among populations receiving natural water with sub-optimal fluoride, with those receiving optimal artificially fluoridated water, with those receiving naturally fluoridated water (where there there is no history of taking fluoride supplements). So water fluoridation could be judged "guilty of increasing" Questionable Fluorosis from 28.4% to 36.0%; Very Mild Fluorosis from 11.9% to 19.9%; Mild Fluorisis from 3.0% to 4.4% but no change in Moderate fluorosis at 0.3% and no change in Severe Fluorosis at 0.3%. I worked out the sample size of the suboptimal fluoride group who didn't take supplements was 41.3% of 2081 = 810. So 0.3% of that is 3 cases. In the artificially fluoridated group, the sample size was 85% of 1445 = 1228. And 0.3% of that is 4 cases. These are tiny numbers, so there really isn't enough data to know, in a large population, how many extra cases of moderate or severe fluorosis are due to water fluoridation, but if this is the best analysis we have, there currently isn't any evidence that water fluoridation is guilty of causing any extra cases of moderate or severe fluorosis. Colin°^Talk 17:48, 28 May 2009 (UTC)

Yes, I think we should state something like "with normal water fluoridation rates of severe dental fluorosis or exceedingly low, however cases have been reported in certain population with risk factors ref, in cases in which equipment has failed and at low rates in populations who are receiving floride from muitiple sources ref" I came across a paper from Africa commenting on how malnutrition increases ones suceptibility to dental flurosis, we have had accedents upnorth that have lead to severe dental fluorosis and death, and have seen papers written about the concerns from fluoride when it is received from muitiple sources which would have been less true in 1980. Cheers --Doc James (talk · contribs · email) 18:56, 28 May 2009 (UTC)

The source doesn't support your proposed text, which will make the reader think the "normal water fluoridation" is responsible for the "exceedingly low rates of severe dental fluorosis". Colin°^Talk 19:12, 28 May 2009 (UTC)

I am not saying that the papers above say the passage I have suggested but I could easily find papers to support what I have just written. This paper for instance found rates of severe fluorosis of 24.1% and 75.9% in mod to high natural fluoride areas. PMID 16430523

Now to set the record straight I am not saying that we should not fluorinate the water we just need to reasonabily discuss the side effects and benefits. Which I will say is mostly done at this point but could use a bit of further clarification.--Doc James (talk · contribs · email) 19:19, 28 May 2009 (UTC)

We need to stick with sources that discuss artificial water fluoridation when dealing with side effects and benefits. Plus, although the initial clause of the proposed text is technically correct, it is quite misleading. Colin°^Talk 19:43, 28 May 2009 (UTC)

Yes. Also, please see my "Severe fluorosis issue" comment below. Eubulides (talk) 08:52, 29 May 2009 (UTC)

Is the page just about artificial water fluoridation or water fluoridation in general? We all agree that some areas fluoride levels are so high they lead to severe dental flurosis in a large portion of the population naturally.--Doc James (talk · contribs · email) 22:19, 28 May 2009 (UTC)

This is just about artificial water fluoridation, but I do think it would be nice to have a picture of more noticeable fluorosis. My little brother and a couple of my cousins have worse fluorosis than the effect seen in that picture. Perhaps we should ask User:Dozenist, the dentist who contributed it, if he can come up with another picture with more noticeable fluorosis, since I'm sure he sees it. II | (t - c) 06:37, 29 May 2009 (UTC)

• The term "water fluoridation" means "controlled addition of fluoride to a public water supply to reduce tooth decay". This definition excludes fluoridation above recommended levels, a topic that is covered in detail somewhere else in Wikipedia. Although the Water fluoridation article briefly discusses the issue of fluoride above recommended levels, it does so only when this is directly relevant to the main topic.
• Any new image should be chosen so as not to mislead a naive reader into thinking that there is reliable evidence that water fluoridation significantly increases the risk of aesthetically-objectionable dental fluorosis. (Such thinking would contradict both the York and the NHMRC reviews, our best reviews.) It's fine to use a image of non-aesthetically-objectionable fluorosis, as we have reliable sources saying this occurs. But aesthetically-objectionable fluorosis would stray from what our reliable sources are saying.

Eubulides (talk) 08:52, 29 May 2009 (UTC)

• Severe fluorosis issue. Some of the above comments are based on the theory that water fluoridation is a significant cause of severe dental fluorosis. However, this simply isn't the case. Here are some comments about the 3 sources cited above:

• Akpata et al. 1997 (PMID 9332811) is not about water fluoridation: it is about water naturally fluoridated above recommended levels. In that primary study, even the 10% of wells that were "low-fluoride" (0.50–0.79 mg/L fluoride) were above the levels recommended by the WHO for water fluoridation (0.5 mg/L in hot and dry climates). Also, the severe fluorosis observed in those wells could easily be explained by halo effects from even-higher-level wells, or by children moving any time in the past dozen years before the study (the study did not examine either issue).
• Wondwossen et al. 2006 (PMID 16430523) is also not about water fluoridation; it is about moderate- and high-fluoride areas in the Ethiopian Rift Valley. Even its "moderate-fluoride" areas mostly consist of wells that are way above recommended levels (in some cases by a factor of 4).
• Beltrán-Aguilar et al. 2002 (PMID 11868834) is directly relevant to water fluoridation, but as Colin said, it directly contradicts the claim that water fluoridation causes severe fluorosis.

While we're on the subject of severe dental fluorosis, unless I'm missing something we haven't seen reliable sources supporting the following claims made in comments above:

• "cases have been reported in certain population with risk factors"
• "we have had accedents upnorth that have lead to severe dental fluorosis and death" (We do have reliable sources on death, and that topic is covered in Water fluoridation #Safety; it's the severe-dental-fluorosis part of this claim that is dubious.)
• "at low rates in populations who are receiving floride from muitiple sources"
• "in cases in which equipment has failed".

Two other comments on dental fluorosis:

• "I came across a paper from Africa commenting on how malnutrition increases ones suceptibility to dental flurosis" Can you please let us know the citation for that? Offhand it doesn't seem directly relevant to water fluoridation, but perhaps the source establishes the relevance.
• Multiple reviews are available on the subject of water fluoridation and fluorosis. As per WP:MEDRS#Definitions and WP:PSTS, the Water fluoridation article should typically defer to what these reviews say, and should not cite primary sources in order to dispute the reviews.

Eubulides (talk) 08:52, 29 May 2009 (UTC)

Here is the paper on equipment failure Waldbott GL (May 1981). "Mass intoxication from accidental overfluoridation of drinking water". Clin. Toxicol. 18 (5): 531–41. doi:10.3109/15563658108990280. PMID 7023807.

Here is papers that discusses many sources [2][3]

This one says "While the increase has occurred primarily in the very mild and mild categories of dental fluorosis, there is also some evidence that the prevalence is increasing in the moderate and severe classifications as well."[4]

--Doc James (talk · contribs · email) 13:40, 29 May 2009 (UTC)

• Thanks for the paper on many sources (Skotowski et al. 1995, PMID 7562728). I followed the reference chain to a recent review that discusses the topic (Alvarez et al. 2009, PMID 19179949, freely readable, yay!) and added some coverage of it. This review isn't the best quality, but it is reliable and it is certainly better than nothing.
• The paper on equipment failure (Waldbott 1981, PMID 7023807) isn't relevant to fluorosis, as it doesn't mention fluorosis at all. More generally, that paper is a primary study of one overfeed incident, and for the overfeed issue we're better off using a reliable review that summarizes the topic. Water fluoridation #Safety already does this, citing Balbus and Lang 2001 (PMID 11579665).
• As far as I know, the primary study about increase in moderate/severe fluorosis (Clark 1994, PMID 8070241) doesn't attribute this to water fluoridation, but to fluoride in general. Also, that study is rather old, and as fluoride practice has changed since then (particularly for infants) its current relevance is a bit suspect. A much more recent primary study by the same author (Clark et al. 2006, PMID 16674751) found no significant difference in dental fluorosis of aesthetic concern after water fluoridation was discontinued in one community, which suggests that water fluoridation was not a significant cause of the problem in that case. In any case Water fluoridation shouldn't be citing either of these primary sources by Clark now that it is citing a reliable review on the topic.

Eubulides (talk) 17:42, 29 May 2009 (UTC)

• Comment I think I'm confused about the difference between "topical fluorides" and the fact that all fluoride therapy works "topically". I'm guessing that fluoridated water doesn't much affect the teeth directly (contact between the water being held in the mouth briefly while drunk) but is absorbed and the fluoride comes back in the saliva. Is that correct? Could we say so in the mechanism section? Out of interest... I'm also guessing that mouthwash has the opposite mechanism in that you don't swallow it so it is only effective while some wash remains in your mouth. One of the sources commented that fluoride tablets can be more effective if sucked for as long as possible. Is that because it can have a directly-topical effect as well as the ingested...saliva route? Colin°^Talk 12:29, 28 May 2009 (UTC)
  • I'm pretty sure your intuition is wrong. When you drink fluoridated water, that water washes over the teeth and perhaps a bit of that water remains in your mouth, exerting a topical effect. Once it's drunk it's either excreted or distributed to the entire body as well as the mouth, significantly diluting any effect it would have on the mouth area. There's a paper which argues that the systemic effect is understated (Newbrun 2007), but I don't have access to the paper, and he's going against the consensus. I'd say at most the systemic effect is 10% (I seem to remember reading that from the NRC), more likely lower. II | (t - c) 07:02, 29 May 2009 (UTC)

I am also confused on the topical vs. topical-saliva issue. I have a few comments on the content issues saved to Notepad, but got distracted before chasing down the reference on topical effects. Perhaps Eubulides could elaborate. On a technical well-written and well-referenced basis though, the article is stellar.

Also, the topical bit I believe is mostly for adults. For children, systemic ingestion may be a little different. Again, it's been a while since I visited the topic, and the discussions are split between this and the "Opposition" article, so it's rather difficult to pin down where this has been discussed previously. Franamax (talk) 00:50, 29 May 2009 (UTC)

Actually, the effect of fluoridated water is almost entirely topical, for both adults and children. A bit of fluoride does come back via plasma to the saliva, but this apparently doesn't benefit teeth much. For many years it was thought that there were systemic effects, but nowadays reliable sources generally agree that systemic effects have little benefit. (Newbrun evidently is an exception, but his 2007 paper is not cited much.) Thanks for bringing up this issue; I added some text to try to clear it up, citing Hellwig & Lennon 2004 (PMID 15153698) on topical vs systemic and Oganessian et al. 2007 (PMID 18780642) on plasma. (And thanks for the compliment, Franamax!) Eubulides (talk) 08:52, 29 May 2009 (UTC)

OK. I think the sentence about "systemic (whole-body) fluoride" is still confusing as it mentions swallowing supplements rather than the swallowing of fluoridated water, which is more directly relevant to this article. Could we find a source that directly states that it is the presence of fluoridated water in the mouth that contributes to fluoride in the saliva and thus to remineralisation. Perhaps also the mechanism section could note that fluoride toothpaste and mouthwash are simply more concentrated methods of delivering fluoride to the mouth. I read with interest in the Sheiham 2001 article that brushing with non-fluoride toothpaste has no effect on dental caries.

If the positive effects of fluoride occur due to what you put and hold in your mouth, and only once teeth have erupted, then the negative effects of fluoride seem to be due to what you swallow, and only up to the age of about eight (ignoring toxic doses). So I think the third paragraph in Mechanism is a bit confusing as it mainly concerns the ingestion of fluoride. I note that your source only indicates that drinking water is "typically" the most important source of fluoride: the article text and the two sources seem to indicate that in low-fluoride-water-areas, ingested toothpaste "may" result in higher fluoride consumption that from the water.

Should the Mechanism discuss the mechanism behind fluorosis, or just stick to the mechanism behind the desired effects? If the the later, then perhaps the body-intake stuff should be moved to the Safety section, and keep this section totally topical. Colin°^Talk 12:44, 1 June 2009 (UTC)

• "Could we find a source that directly states..." I attempted that, citing Tinanoff 2009 rather than Oganessian et al. 2007. I couldn't offhand find a source making the "more concentrated" point, though obviously it's true.
• "I read with interest in the Sheiham 2001 article that brushing with non-fluoride toothpaste has no effect on dental caries." Good point; I added that.
• "the third paragraph in Mechanism is a bit confusing as it mainly concerns the ingestion of fluoride ... 'typically' ... 'may'" Thanks; I tried to fix that.
• "Should the Mechanism discuss the mechanism behind fluorosis" Yes, I thnk so, and the change cited in the previous bullet also attempts to do that.

Thanks for the comments; they're helping to improve the article. Eubulides (talk) 09:33, 2 June 2009 (UTC)

• Comment about alternatives. This section is a bit of a jumble; the lead sentence is particularly hard to parse. Covering the mix of theoretical and unproven methods before covering the proven standard methods (in detail) is a mistake IMO. How about abandoning the lead paragraph and have the following paragraphs: 1. Fluoride toothpaste - head and shoulders the most important and effective alternative. 2. Other community programmes(salt, milk, healthy-eating, etc) 3. Other personal methods (mouthwash, sealants, chewing gum etc). 4. Theoretical, research and unproven ideas. Colin°^Talk 20:55, 1 June 2009 (UTC)

• Thanks for the suggestion. I installed a change that did much of what you suggest. It puts the unproven stuff after the proven stuff. It turns out that "healthy-eating" doesn't work, by the way; I guess nobody follows the regimen. (Our summary of Kumar 2008, PMID 18694870, briefly discusses this.) However, I left the sealants first, as they're the most effective; put the fluoride mouthwash next to the other fluoride treatments; and put chewing gum later. Eubulides (talk) 09:33, 2 June 2009 (UTC)

• Comment on cost. The numbers here are all relative, with the aim of showing it is cost-effective. But since they are small, they are perhaps hard for the reader to appreciate the total cost of tooth decay. Your Sheiham 2001 paper claims "Dental diseases, particularly dental caries, are the most expensive part of the body to treat. Caries is indeed the most expensive human disease in terms of direct costs. For example, the direct costs of caries treatment in Germany was 20.2 billion, CVD 15.4 billion DM, diabetes 2.3 billion DM" (citing an 1993 paper). It would be nice to have up-to-date figures for the direct cost of caries -- to give the reader the idea of the big pot of money that is worth reducing, even by a small amount. The "Caries is the most expensive human disease in terms of direct costs.", if justified, is certainly eye catching enough to appear in the lead. Colin°^Talk 20:55, 1 June 2009 (UTC)

• Thanks again. I installed a change, both to Goal and to the lead, that mentions that caries is the most expensive disease and cites Sheiham. Eubulides (talk) 09:33, 2 June 2009 (UTC)

• Support. I've finished re-reading this and it is excellent. Per previous FAC: readable, comprehensive and sticks closely to high quality sources. A good set of appropriate pics too. Colin°^Talk 12:20, 2 June 2009 (UTC)

• Comment Support Shortly after this article was not promoted, I said that I'd wished I'd voted support. It is much better than probably most featured articles, and Eubulides has done a pretty good job of presenting both sides, although it's taken some nudging. He also has a tendency to repeat things word for word if they've been "published", particularly in a "review", regardless of the supporting data presented. I was reading the lead and I looked closer at the statement in the lead: "Almost all major public health and dental organizations support water fluoridation, or consider it safe", sourced to Armfield 2007. Armfield cites the American Dental Association's Fluoridation Facts 2005 to support this statement. The ADA's statement on this can be found on page 6, with a further list on page 69. These organizations are almost exclusively Anglo, with the exception of the Anglo-dominated World Health Organization. European and Asian safety organizations are not mentioned. And their absence makes it "almost"? It's not surprising that countries which practice fluoridation officially support it. But what do the academics say? In fact, the most in-depth review of the topic, the York review (which served as the basis for the later more surface-level NHMRC review of reviews) concluded that research on adverse effects was mostly of low-quality, which is in the lead. Anyway, the ADA's statement, channeled through Armfield, seems dubious, especially given letters which fluoridation opponents have received from European and Asian organizations [5], which indicate that they're more in agreement with York that the safety hasn't been conclusively established. Armfield's statement on health organizations is not as dubious as some of Armfield's other statements, like the one which directly precedes his public health org. statement: "Statements regarding the scientific controversy surrounding water fluoridation are generally regarded as artefacts of antifluoridationist activity, with actual scientific debate over water fluoridation being resolved decades ago", sourced, if you can believe it, to a 1978 Consumer Reports article. Fortunately, that's not in the article. Armfield's statement contrasts interestingly with a statement from one of the most prominent toxicologists alive today, John W. Doull, who chaired the 2006 NRC report on high natural fluoride. Doull told a Sci. American journalist [6]: "when we looked at the studies that have been done, we found that many of these questions are unsettled and we have much less information than we should, considering how long this [fluoridation] has been going on. I think that's why fluoridation is still being challenged so many years after it began. In the face of ignorance, controversy is rampant". There's also the interesting statement from Burt & Tomar that fluoridation is more justified in the U.S. than Europe because of socioeconomics; unlike Armfield and the ADA's statements, this bold statement is entirely unsupported by any citations or data. However, because it's in a "review", it apparently passes muster to be included in the lead. I'll admit it's plausible. II | (t - c) 06:37, 29 May 2009 (UTC)

Thanks for bringing up Armfield's hyperbole; I reworded the article to remove it, citing Pizzo et al. (a more skeptical source) instead. Burt & Tomar's statement about socioeconomics is indeed plausible; also, Burt and Tomar are recognized experts in the field and we have no reliable sources disputing their statement. If any other points need clearing up to get your support this time around, please let me know. Eubulides (talk) 08:52, 29 May 2009 (UTC)

Using Armfield 2007 to support the "opposition to it has been based on ethical, legal, safety, and efficacy grounds" clause seems a bit inflammatory and unfair, but I suppose it's balanced by the Cheng et al's BMJ article. II | (t - c) 21:25, 1 June 2009 (UTC)

II's comments seem verging on WP:SYNTH there. I'd have a minor gripe about U.S. bias in the article, , but the pros and cons of fluoridation are presented admirably. Physchim62 (talk) 20:32, 1 June 2009 (UTC)

Removing obviously implausible and poorly-supported statements is just an exercise of good editorial judgment. II | (t - c) 21:25, 1 June 2009 (UTC)

• Comments - sources look okay, links checked out with the link checker tool. Ealdgyth - Talk 12:16, 29 May 2009 (UTC)
• Support - In my view the article satisfied the criteria at the last FAC; it surpasses them now. Graham Colm ^Talk 16:32, 30 May 2009 (UTC)

Image review: images are verifiably in the public domain or appropriately licensed. No issues. Jappalang (talk) 03:23, 2 June 2009 (UTC)

The above discussion is preserved as an archive. Please do not modify it. No further edits should be made to this page.