“Children with chronic exposure to high levels of fluoride in drinking water made more errors on drawing and cognitive tests, according to a new pilot study by researchers at Tulane University…
For the study, researchers recruited 74 children ages 5-14 from demographically and ethnically similar rural Ethiopian farming communities with varying levels of natural fluoride in their community wells, ranging from 0.4 to 15.5 mg/L.The U.S. Public Health Service recommends 0.7 milligrams per liter (mg/L) as the “optimal level” for water fluoridation and the World Health Organization recommends that fluoride levels be kept below 1.5 mg/L.”