> such as drinking water containing more than 1.5 milligrams of fluoride per liter
> The PHS panel that provided the recommendation considered all sources of fluoride intake and recommended 0.7 mg/L as the concentration that maximizes fluoride's oral health benefits while minimizing potential harms, such as dental fluorosis.
1.5mg/L was where effects could possibly start to be detected. That's over twice the recommended concentrations.
> It is important to note that there were insufficient data to determine if the low fluoride level of 0.7 mg/L currently recommended for U.S. community water supplies has a negative effect on children’s IQ.
> The PHS panel that provided the recommendation considered all sources of fluoride intake and recommended 0.7 mg/L as the concentration that maximizes fluoride's oral health benefits while minimizing potential harms, such as dental fluorosis.
1.5mg/L was where effects could possibly start to be detected. That's over twice the recommended concentrations.
https://www.cdc.gov/fluoridation/about/community-water-fluor...
From the NIH source above posted by WorkerBee:
> It is important to note that there were insufficient data to determine if the low fluoride level of 0.7 mg/L currently recommended for U.S. community water supplies has a negative effect on children’s IQ.
https://ntp.niehs.nih.gov/whatwestudy/assessments/noncancer/...