Fluoride absorption through the mouth
Now it is proven how fluoride can badly affect health, damage brain, bones and lower IQ. So I want to avoid it getting into my body. Fluoride can also be absorbed through skin. How much percent of it gets absorbed through mouth while using toothpaste, which for example contains 1040ppm of sodium fluoride?
I also doubt that while washing teeth with toothpaste none of it is ingested, even after spitting it out. More or less is ingested. Please provide research sources.