You’re wrong on both counts. The geology of many areas cause excess fluoride in well water without any government intervention, which can then become worse when using fluorinated toothpaste. It’s rarely a significant issue in the US, but gets far in some countries.
“These sources include drinking water with fluoride, fluoride toothpaste—especially if swallowed by young children” Ie: swallowing makes it worse but the point of fluoride in toothpaste is to be absorbed, so some will get absolutely even in those who already have issues.
Yeah rat poison can't harm humans regardless of form, concentration, age or literally any possible factor. Trust us with lives of your kids, we say so.
(just to be clear I am a rational science freak, but my kids have higher priority and we know scientists and corporations have messed up more than once, not going into 'just trust us' with literal poison just because it has good side effects on teeth)
Only at low levels: “Moderate and severe forms of dental fluorosis, which are far less common, cause more extensive enamel changes. In the rare, severe form, pits may form in the teeth.”
“These sources include drinking water with fluoride, fluoride toothpaste—especially if swallowed by young children” Ie: swallowing makes it worse but the point of fluoride in toothpaste is to be absorbed, so some will get absolutely even in those who already have issues.
https://www.cdc.gov/fluoridation/faqs/dental_fluorosis/index....