[jcranmer]

Nobody fluoridates the water to 1.5 mg/L. If you're fluoridating the water, your target is 0.7 mg/L.

The people with 1.5 mg/L fluoride (or higher--the EPA limit is 2.0mg/L) are because the groundwater is percolating through rock that is high in fluorides, and people don't want to spend the money on defluoridating the water down to acceptable standards. Defluoridation is of course much harder than fluoridation because fluorides are highly soluble.

[neuroelectron]

Yes, because people only drink a certain amount of tap water so you know they're getting the recommended dosage of fluoride.

[btreecat]

Fairly bad faith argument on your part.

The limits are set such that if you _only_ drank tap water you won't consume more than the safe limit. If you then reduce how much tap water you consume because you get hydration from other sources, your well under the limit.

Not accounting for someone eating tubes of fluorinated toothpaste, which is out of specified usage.

[neuroelectron]

OK, that makes sense. What is the recommended dosage of fluoride?

[btreecat]

The current upper limit consider safe to consume with regularity, is "4 milligrams of fluoride per liter of water"

The CDC sets the recommend fluorination levels are 0.7 mg/L, more than 4x lower than the amount considered safe to consume.

So you would need to consume over 20L of water (think 10 2L soda bottle worth).

I couldn't personally physically do that.

[newZWhoDis]

Absolute nonsense.

The coffee, soda, beer, or kombucha you drink was made with fluoridated water. Your salad was grown with fluoridated fruit was washed in fluoridated water.

Fluoride permeates modern supply chains because it’s literally in the water which is an input to countless things.

Fluoride proponents have utterly failed to control dosage and harmed public health in doing so.

[btreecat]

> Absolute nonsense. > Hardly but let's have fun!

> The coffee, soda, beer, or kombucha you drink was made with fluoridated water. Your salad was grown with fluoridated fruit was washed in fluoridated water. >

How much flouride? And from what sources?

Typically farms need wells because of how much water infrastructure they need can't generally be supported by municipal water. There are exceptions particularly in dense areas with vertical farms or urban farms but this doesn't align with your claim, that effectively everything we consume has some detectable level of flouride.

I bet you've already read this though

https://ods.od.nih.gov/factsheets/Fluoride-HealthProfessiona....

The only thing studied that contained more flouride than municipal water but still 3x less than the safe limit, is tea. And that was measured with distilled water to eliminate the water source as a variable.

Most tea isn't grown in the USA.

So your claims fall flat on their face here, but I'm not done.

> Fluoride permeates modern supply chains because it’s literally in the water which is an input to countless things. >

How much? Making such a claim is fine if we want hand waved values. But when you want to be an Internet advocate for a specific policy, show up with receipts or don't show up at all.

See previous link for current source of information on food supply.

> Fluoride proponents have utterly failed to control dosage and harmed public health in doing so.

Based on what evidence?

You have utterly failed to show you have a solid grasp on the scientific method, public policy, and critical thinking.

[brianbrown]

1. Most tea consumed worldwide is of Asian origin. Camellia sinensis is native to East Asia.

"On any given day, more than one half of the American population drinks tea. On a regional basis, the South and Northeast have the greatest concentration of tea drinkers."

Source: https://www.teausa.com/teausa/images/Tea_Fact_2021.pdf

Tea may easily contain 5 to 10 times as much fluoride as fluoridated water.

2. TOTAL intake is what determines fluoride toxicity. This has been established since the 1930s when fluoride was discovered to be the source of "mottled enamel" - dental fluorosis.

In 1991, total intake among adults in fluoridated areas in the US was estimated to be up to 6.6 mg/day. (US PHS, 1991)

"The daily intake of most adults is about equally divided among food, drinking water, beverages, and mouthrinses." (U.S. Dept. Health & Human Services, Report on fluoride benefits and risks. MMWR Recomm Rep. 1991 Jun 14;40(RR-7):1-8. PMID: 2051975.)

[newtonsmethod]

While you are right that it is very rare that a water system will fluoridate their water to levels of 1.5 mg/L, I don't think it's true that all systems fluoridating their water have targets or achieve a level of 0.7mg/L. You can see in the EPA's analysis of their fourth Sixth Year Review (SYR4) (https://www.epa.gov/system/files/documents/2024-04/syr4_fluo...) that there is a large variation in the fluoride concentrations of fluoridated entry points (from 0.6mg/L to 1.2mg/L, with the 0.6mg/L cut-off being artificial).

The NTP monograph doesn't conclude that fluoridation at levels of 0.7mg/L are safe or unsafe, but it is better to be safe than sorry. With some populations receiving fluoridated water at concentrations of 1.2mg/L and an estimated 2% to 7% of the population receiving water fluoridated above this concentration, I think it's reasonable to be concerned in light of the NTP's monograph on fluoride (even if this just means to increase focus on de-fluoridation of water).

As per the NTP: > The moderate confidence conclusions may also be relevant to people living in optimally fluoridated areas of the United States depending on the extent of their additional exposures to fluoride from sources other than drinking water.

Also just to note, the EPA's secondary maximum contaminant limit (SMCL) is 2.0mg/L. This isn't the federal limit as set forth by the MCL of 4.0mg/L, but notice is still required by the EPA here.

Taking the recent Cochrane report in mind, which shows a small reduction of 0.24 decayed tooth per child in places practicing fluoridation, and fails to find high quality studies on the effects of fluoridation for adults, it is reasonable to question the EPA's limits and the US's policy of fluoridation.

I can't find any strong evidence for the benefits of systemic ingestion of fluoride which makes me ultimately conclude that the policy is an ineffective one of forced medication (in the name of those who can't brush their teeth).

With no evidence of it being a safe policy, I don't know why the CDC and EPA still advocate nowadays for water fluoridation. Although perhaps costly to change, neither do I know why the EPA sets their limits to levels above where known harms (such as dental fluorosis and neurodevelopmental effects) occur. As Judge Edward Chen says:

> In all, there is substantial and scientifically credible evidence establishing that fluoride poses a risk to human health; it is associated with a reduction in the IQ of children and is hazardous at dosages that are far too close to fluoride levels in the drinking water of the United States.