Comment by oaktrout

The study and my quote literally say " drinking water containing more than 1.5 milligrams of fluoride per liter".

It did not find it lowered IQ in all drinking water concentrations, but it definitely found it in some drinking water concentrations.

So yes, they did explicitly find fluoride in drinking water at certain concentrations was associated with lower IQ.

Are you defining "drinking water concentrations" as "concentrations that have not been shown to be associated with lower IQ."?