My honest opinion:
Change your diet to a plant-based diet. Karma-free food. Less processed stuff, less conservative additives.
Eat clean, eat healthy.
No need for fluoride. Third eye calcification might be true. Scientists don't know everything.
It's not harmful in low dosages? How can they be so sure?
This is more scientific: It's probably not harmful in low dosages.
So there is this probability. I rather live without unneccessary chemicals and keep it natural, clean and healthy.