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Yup; it's absolutely terrifying.

The scales chosen in the study make it sound a lot more scary, though, given the unfluoridated mean intake was 0.3 mg and the fluoridated mean intake was 0.93mg. Still, this is an estimated difference of two whole IQ points between the populations.

I'm on Detroit water and just checked the latest water test I could find -- .57ppm fluoride. If I did the math right, there is 1mg fluoride in every .46 gallons of water.

Additionally, the maximum level allowed in my city is 16mg per gallon, and has been since I was born. However, in the year I was born(1992) the maximum measured level per the city test was 48mg per gallon.

Compare with average ingestion of fluoride salts from toothpaste. (Nobody precisely rinses teeth after applying it.)

P=.04 is barely significant. What it means is that further research may be worth pursuing, not that we found conclusive evidence.

I am personally a bit spectical, sounds too big to be true. Here is an illustration of what I am saying https://xkcd.com/882/