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by colordrops 1215 days ago
This is not a good faith argument to claim that fluoride and water are in the same class of substances when it comes to toxicity.

Also you are wrong that all flour in the US must be enriched. I have some unenriched flour on my shelf right now.

https://www.hsph.harvard.edu/news/features/fluoride-children...

2 comments

I’m not implying they’re in the same class, I’m saying that the level used is implicitly important in saying whether or not something is toxic. To me it’s not a good faith argument to assume otherwise.

You’re right I was wrong about enrichment [1] - I didn’t know that. It is wide spread, however.

The study you cited seemed to be from areas of naturally occurring high levels. So I guess I should further qualify my statement - I am to mean that it’s non-toxic at the levels used in municipal water and in toothpaste. I thought you were saying there were studies suggesting otherwise at the levels used, which the CDC disagrees with [2]. I’m now rereading your comment where you talk about the levels used so you did address that. Apologies for not better latching onto that. But it did make it sound like these levels in use were potentially toxic, which has been very widely studied across many countries over decades with increasing life expectancy and dental improvements, so it would be very unexpected if so.

It seems that there isn’t a federal requirement for fluoride in municipal water - perhaps there are areas that don’t.

[1] https://www.fda.gov/media/94563/download

[2] https://www.cdc.gov/fluoridation/faqs/community-water-fluori...

To claim that dose is the only factor involved is bad faith, or at least overly simplistic. For example, radiation and lead are cumulative. There is no minimum safe dose. Can you say definitively that there is no damage or cumulative effect from regular small dosages of fluoride?

Did you look at the study? The naturally occurring levels are below levels added to water in the US in many of the regions studied.

In any case you should be able to see that I'm not coming at this from some conspiracy nutjob angle but from sourced studies and reasonable thought processes.

My point is not that you are wrong. It's that, even if you are right, it's not some obvious open and shut case.

The Harvard quoted study above looks at children in China in areas with high levels in groundwater .. high being of the order of 3-11 mg/litre.

The correlated 'damage' cited was of less than half an IQ point observed difference at the upper end of the high levels.

The fluoride doses used in water treatment (here in Australia) are at most 1 mg/litre.

The amounts with measurable cognitive deficits were less that the amounts added to drinking water in the US in several of the Chinese regions. It's in the study's data.
The study Developmental Fluoride Neurotoxicity: A Systematic Review and Meta-Analysis [1] (discussed in your link above) has data on drinking water in China.

It includes quotes relavant to the USofA:

    Such circumstances are difficult to find in many industrialized countries, because fluoride concentrations in community water are usually no higher than 1 mg/L, even when fluoride is added to water supplies as a public health measure to reduce tooth decay.
and

    In response to the recommendation of the NRC (2006), the U.S. Department of Health and Human Services (DHHS) and the U.S. EPA recently announced that DHHS is proposing to change the recommended level of fluoride in drinking water to 0.7 mg/L from the currently recommended range of 0.7–1.2 mg/L, and the U.S. EPA is reviewing the maximum amount of fluoride allowed in drinking water, which currently is set at 4.0 mg/L
Note that the U.S. EPA is reviewing the maximum amount of fluoride allowed in drinking water concerns levels naturally occuring and is not a recommendation to add fluoride to US drinking water in excess of 1 mg/litre.

I am unable to find data in that report that supports your assertion.

If you have data you wish to draw eyes to then please quote the numbers and link to the source.

[1] https://ehp.niehs.nih.gov/doi/10.1289/ehp.1104912

The problem is that it's an EPA recommended dosage, and not regulated nationwide, leading to a large variance in levels. "The fact that fluoridation of water is not regulated nationwide leads to a challenge for individuals interested in generating meaningful data for nationwide databases." [1] In the short list of measurements in the quoted paper, it ranged from almost nothing to 1.5 mg/L, and that's a very small sample. Borden County in Texas has levels above 5.5 mg/L in some areas [2]

[1] https://www.ars.usda.gov/ARSUserFiles/80400525/Articles/jfca...

[2] https://www.beg.utexas.edu/files/content/beg/research/TCEQ_s...

You still have not supported the claim made above that:

> The amounts with measurable cognitive deficits were less that the amounts added to drinking water in the US ...

Your first link ( [1] ) cites a source in Springfield as the maximal value seen (in that report) of 1.5 mg / litre (with no mention of whether that's due to added fluoride or a result of natural fluoride in the groundwater).

Your second link ( [2] ) is about an untreated groundwater source that serves 150 people with:

    Fluoride has been detected between 4 milligrams per liter (mg/L) and 5.57 mg/L from July 2002 to March 2007, which exceeds the maximum contaminant level (MCL) of 4 mg/L as well as the Secondary MCL of 2 mg/L set by the USEPA.
and is titled as a DRAFT FEASIBILITY REPORT looking at the costs of treatment with (for example) :

    Centralized treatment alternatives for arsenic and fluoride removal have been developed and were considered for this report; ...
To summarise; you have claimed but not demonstrated that intentional treatment in the USofA has added fluoride to reach levels that (are assumed | correlated ) caused IQ losses of less than half a point in China.

Your link clearly do not support this, Borden County is untreated and the intent is to look at reducing the high fluoride levels.

You should re-read the study I linked:

"The average loss in IQ was reported as a standardized weighted mean difference of 0.45, which would be approximately equivalent to seven IQ points for commonly used IQ scores with a standard deviation of 15."

Seven points IQ difference.

Also, if you bother to look at the data in the linked paper, many of the regions with measurable deficits were in the 0.5 to 2 mg/L range, well within typical treatment levels in the US.