According to the Journal of Dental Research (Whitford 1987, 1990), there is enough fluoride in a tube of children’s fluoride toothpaste to kill an average-weighing child under the age of 9. Why else would the FDA require the following warning label on fluoride toothpaste?
“WARNING: Keep out of reach of children under 6 years of age. If you accidentally swallow more than used for brushing, seek professional help or contact a poison control center immediately.”
The 1984 Clinical Toxicology of Commercial Products rates lead’s toxicity at 3-4, while fluoride is rated at 4 (3 = moderately toxic; 4 = very toxic).