Childhood fluoride exposure has no effect on IQ.
About a year ago, the city of Portland, Oregon was in the news because of its water supply-and not because a teenager decided to relieve himself into a reservoir. Instead, the issue was fluoridation, the addition of trace amounts of fluorine to municipal drinking water. Fluoridation is widespread in the US, as copious evidence indicates it improves oral hygiene. That evidence prompted the Portland City Council to approve fluoridation-only to see voters reject that plan by a wide margin. While some of the opposition focused on the finances of the deal for the fluoridation process, concerns about the safety of fluoridation also played a major role in organizing the opposition.
It turns out that a similar drama had been playing out in New Zealand, where the city of Hamilton reversed course on water fluoridation several times over the past two years. Now, in response to the kerfuffle, some New Zealand researchers (combined with a ringer from Duke) have looked into one of the supposed health threats posed by fluoridation: it stunts the mental development of children. Their new report finds no evidence of this, however. In fact, children who grew up with fluoridated water had slightly higher IQs than their peers, though the difference wasn't statistically significant.
(Score: 5, Insightful) by VLM on Tuesday May 20 2014, @08:08PM
Gimme a reaction mechanism. Its not enough to show a correlation, need to have a plausible biochemical reason. And fluorine and its ions are ridiculously active, so how it would get into the bloodstream and then cross the blood brain barrier and then finally do "something" to nerve cells to make people dumb sounds pretty unlikely to me.
Enough to screw up your nerve cells would melt your bone structure completely away first.
(Score: 5, Funny) by MozeeToby on Tuesday May 20 2014, @08:13PM
Screw logic! Protect the purity of essence of our precious bodily fluids!
(Score: 4, Funny) by hubie on Tuesday May 20 2014, @08:19PM
(Score: 1, Interesting) by Anonymous Coward on Tuesday May 20 2014, @09:05PM
So if you substantially increased the concentration of fluoride it won't have much of an effect?
"The fatal period ranges from 5 min to 12 hours.[24] The mechanism of toxicity involves the combination of the fluoride anion with the calcium ions in the blood to form insoluble calcium fluoride, resulting in hypocalcemia; calcium is indispensable for the function of the nervous system, and the condition can be fatal."
http://en.wikipedia.org/wiki/Fluoride#Safety [wikipedia.org]
(Score: 2) by Covalent on Wednesday May 21 2014, @02:49AM
Your link says that 10L of fluoridated water delivers 10mg of fluoride ion. Let's multiply the concentration by 10 ... that makes 10L of water equivalent to 100mg of fluoride.
4 grams of sodium fluoride is the minimum fatal dose, which would require consumption of 400L of this extra-concentrated water. In a day. That's around 100 gallons for us Americans. 100 gallons of water in a day would kill you straight away from water toxicity...no fluoride required.
Now I know a smaller dose might be still dangerous, but like every drug, it's all about dosage. At 1ppm, there's no chance of getting anywhere close to a dangerous quantity.
You can't rationally argue somebody out of a position they didn't rationally get into.
(Score: 0) by Anonymous Coward on Wednesday May 21 2014, @02:34PM
Duh but that's not the point I was making. The point I was making (perhaps I should have added emphasis on the words nervous system) is that there is a potential reaction mechanism that could cause fluoride to reduce IQ. I'm not saying it does at these concentrations just that there is a potential mechanism.
So when someone suggests that there is no plausible mechanism it could cause a decrease in IQ I call nonsense. If there is statistically significant data to suggest fluoride reduces IQ then I would say here is a possible mechanism.
If there is statistically significant data to suggest that fluoride does lower IQ then just because this person can't personally think of a mechanism doesn't mean that the data should just be disregarded. By his logic since he personally doesn't know of or can't think of a mechanism then we should all just not conduct any studies on it at all and just go on assuming that it has no effect. By that logic much of what we know in modern science would not have ever been discovered because often times researchers first discover patterns before further investigating the cause of those patterns instead of just noticing a pattern, thinking 'gee, I can't think of any mechanism that could cause this' and ignoring the issue from there.
For instance it was first noticed that previous exposure to cowpox may confer immunity to smallpox. At the time of this discovery no one knew anything about the immune system or the mechanisms of immunity. But it was by further investigating these patterns that advancements in our knowledge were made.
So, no, conducting studies on fluoride is an important part of determining the impact it has. I don't care that this one person can't personally think of a mechanism, if there is statistically significant data suggesting fluoride does X then his personal inability to figure out why doesn't mean we should just disregard the data.
(Score: 3, Insightful) by Covalent on Wednesday May 21 2014, @02:45AM
This is exactly correct. Fluoride is reactive enough to react with the calcium minerals in your teeth...there's no way it's getting into your blood in its pure form.
What this study re-re-re-reconfirms (because this result has been arrived at a large number of times) is that whatever fluoride is becoming on its way into your body, it doesn't lower your IQ.
Take off your tin foil hats people...fluoride is just one of those things that really is good for you in small quantities and bad for you in large quantities.
You can't rationally argue somebody out of a position they didn't rationally get into.
(Score: 3, Insightful) by VLM on Wednesday May 21 2014, @11:21AM
"one of those things that really is good for you in small quantities and bad for you in large quantities."
I don't think the general public understands this chemistry concept.
(Score: 1, Insightful) by Anonymous Coward on Tuesday May 20 2014, @08:38PM
What makes the Duke researcher a ringer? Seems a strange way to refer to professional academics
(Score: 3, Interesting) by kaszz on Tuesday May 20 2014, @09:01PM
Checklist:
* Who financed the study?
* What feature career offers were made?
* Any "irresistible" offers you can't refuse?
* Is the sampling technique correct?
* Is the selection of samples without bias?
* Algorithms used has been scrutinized?
* Falsifiable theory?
* Any second opinion research independent of the first?
* Are the ones executing the research competent enough?
* Blind spots in the methodology?
* Long term effects that show up way later?
* Getting sick is also bad. IQ is not everything. Checked that?
* Let people make their own choice?
* Did side track hints get checked even if they would wreck the main study? or was that just to inconvinient?
* Check the facts - credentials are usually a distraction for poor minds.
"The researchers found that airplanes are impossible because they weigh more than air." :P
There's a lot into determining things. It's usually not "study X found Y and thats it!".
(Score: 2) by kaszz on Tuesday May 20 2014, @09:03PM
Oh I forgot. Sometimes whole societies are so ingrained with bias so very very few people see the whole picture.
(Score: 0) by Anonymous Coward on Wednesday May 21 2014, @01:48AM
What's your point? Are you saying that we should do this work for you and come back with a study on the study? Or are you FUDding this study to protect yr bodily fluids?
(Score: 2) by Appalbarry on Wednesday May 21 2014, @02:44AM
IQ has big effect on beliefs about Childhood Fluoride Exposure.
(Score: 2) by jimshatt on Wednesday May 21 2014, @07:07AM
(Score: 2) by mechanicjay on Wednesday May 21 2014, @11:30AM
My VMS box beat up your Windows box.