Although it is more poisonous than many heavy metals.

I've seen the falsehood that fluorine is a heavy metal repeated on the internet several times, when in fact fluorine is the VERY LIGHTEST HALOGEN.

    For additional info about underlined words, hold your pointer over them.

    When someone claims that fluorine is a heavy metal, you can be sure of a few things:
    1. That if they are not intentionally dishonest, they at least are willing to repeat an unproven statement as fact;
    2. And that they know nearly nothing of even elementary chemistry;
    3. And therefor lack personal and reliable knowledge of the chemistry of other subjects such as nutrition, medicine, biology, etc.

    Fluorine (atomic number 9) is lighter than many metals essential to human (and other) life, such as sodium (atomic #11), magnesium (#12), potassium (#19), calcium (#20), iron (#26), cobalt (#27), copper (#29), and zinc (#30). Those metals below #21 are not considered "heavy". Iron (#26) and above are.

    Fluorine IS a HALOGEN. Halogens are not only NON-metals, but they are on the OPPOSITE side of the periodic table. In other words, as "non-metal" or electronegative as you can get!

    Someone may have thought that only heavy metals are poisonous, or that all heavy metals are, but: There ARE heavy metals that are relatively nonpoisonous. And there are light elements, both metals and non-metals that are VERY poisonous.

    You might think that an M.D. (such as doctor Joseph Mercola) would be a reliable source for chemical information, but it was on his site that I first saw this misinformation. In fact, I've known several doctors that were fairly ignorant of chemistry outside of that they regularly used. And obviously, when confronted with an example outside that regular usage, Dr. Mercola didn't bother to check. (This may be a common problem among some doctors. I've noticed a tendency for some of them to be egotistical and even arrogant.)

    In Thomase's ebook "Surviving Survivalism" (I can't find his signature, even a pseudonym) He uses this imaginary quote:
    "Hey, why not feed it (fluoride) to the people! Let's put it in their water! After all, it's only a heavy metal and would go straight to their brains!"
    It's all very well to point out how poisonous fluoride is, but to call it a "heavy metal" hurts anyone's credibility. He should have also pointed out that it's virtually impossible to buy a toothpaste that doesn't have floride in it.

    I haven't cited this information because there are so very many references in the chemical domain that would of necessity agree. However, almost all of the information presented here can be found in John Emsley's book, "Nature's Building Blocks", 2003, Oxford University Press, and also on wikipedia.

    2nd Edition
    FL101 2013