Oh oh, I've got one too. It's not containing Asbestos but Thorium (or Radium respectively) tho.
"Doramad radioactive toothpaste"
"Creates natural freshness in the mouth!"
"Special biological healing effects by radium rays. A thousand times medically prescribed and recommended."
"What does Doramad do? Through its radioactivity, it increases the defenses of teeth and gums. The cells are charged with a new vigorous life energy, which inhibits bacteria in their destructive ability. Hence the exquisite prevention and healing effect on gum diseases. Polishes enamel to the softest shiny white. Prevents tartar approach. Good foam, new taste, pleasant, mild and refreshing. Use extensively."
Quick disclaimer: The last two quotes can be found on Wikipedia but they are not backed up with sources.
The irony is that production was only stopped after Hiroshima and Nagasaki as nobody wanted to buy radioactive toothpaste any more. So the US which developed nukes against the Germans actually saved the Germans from radioactive poisoning by dropping said nukes on Japan.
One could say it left a bitter taste in some German's mouths. ^(I couldn't resist)
It's because of that kind of thing that I'm always skeptical of startups bringing new and shiny things, that weren't properly studied or tested, and promising to revolutionize something.
Weapons grade teeth.....you should only have 20 teeth left at adulthood to safely use this product with a 90% chance of having no chain reaction events.