This blog is my attempt to reconnect with the world of chemistry. I have a PhD in Inorganic Chemistry and make a living doing research for a large company in Michigan. As times have changed, that company has changed its focus and I no longer have as much chance to do the basic, fundamental research which I most enjoy. Through this blog, I am hoping to recapture the magic which I felt during my graduate (and undergraduate) days in college. Expect topics on chemistry and alchemy along with some non-chemistry related items which I think might be interesting.

"The chymists are a strange class of mortals, impelled by an almost insane impulse to seek their pleasure among smoke and vapour, soot and flame, poisons and poverty; yet among all these evils I seem to live so sweetly that may I die if I would change places with the Persian King."

Johann Joachim Becher (phlogistonist)
Acta Laboratorii Chymica Monacensis, seu Physica Subterranea, (1669).

Thursday, March 6, 2008

Dangers of HF

Today I received an email from my supervisor informing me of an online training session to cover the handling of hydrofluoric acid. Included was a story about a chemist at another company who had apparently been exposed to HF, had simply washed their hand, and concluded that it was no big deal. By the next day the chemist had reported to the hospital, and after 2 more days there had been a good chance of losing the end of his/her finger!

Everything apparently turned out fine, but HF is some really nasty stuff. I used some of it once as an undergraduate, but because my advisor had warned me of the danger, I was very careful. Knowing what I know now, he probably could have given me even sterner warnings. With a pKa around 3, it is one of the stronger weak acids, but it's the F- that causes most of the damage. Fluoride ion is quite toxic. It can penetrate deeply into the skin, forming CaF2, which depletes calcium levels in the body. According to one source, skin burns of 25 in2 or greater can result in serious systemic toxicity and death. Calcium gluconate or calcium carbonate gels are the first line of defense in case of skin exposure, precipitating CaF2 before it can work its way into the skin. Fortunately, I do not ever forsee myself using HF again.

This is a reminder that chemistry can be a dangerous business, especially when we start taking things for granted. I've had a few close calls over the years, but I've never been hurt. I wish everyone could be so lucky.

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