Wednesday, November 9, 2011

Hermetically Soiled

The Mercury Dime. The winged cap was supposed to be a Phrygian cap, symbolizing free thought: (footnote 1).  The design also featured a fascia on the reverse which was fitting, considering the time period.

I'm getting way ahead of myself in the Periodic Table, but elemental mercury is such cool stuff.  Here is a photo of a man floating on a vat of mercury, originally published in National Geographic Magazine:

Man floats on mercury
The acute toxicity of elemental mercury is overblown. Mercury is mainly a chronic poison, meaning it takes long term exposure to do serious damage. Mercury compounds--especially methyl mercury--are a different story. I have been slowly ridding myself of silver amalgam filings, but the brain damage may be too late. :)

Mercury has a long medicinal history. Alchemists believed that it had healing powers. When I was a kid, my dad would treat us with what we called "sting medicine." Marketed as mercurochrome, merbromin doesn't actually contain any chromium --rather the name "chrome" refers to the bright reddish orange dye attached to the mercuric ion. The last time I saw or used mercurochrome was in Italy in 1979. I "smuggled" some back, thinking it was a controlled substance. It is still freely--though not widely--available here. The Straight Dope wrote a piece on mercurochrome here: link.

Of course I played around with elemental mercury quite a bit as a chemist.  The most mercury I ever saw in one place was in a Toepler pump, a device which uses a mercury piston to collect and measure non condensable gases like methane and carbon monoxide.

Here's a modern quandary: incandescent bulbs use more watts of power than the newer mercury-containing CFL bulbs. Burning coal emits tons of mercury into the atmosphere. The EPA and others claim that smokestack emissions are not scrubbed link, even though the technology exists. Link

I think it's ironic that we need to disperse mercury in order to rid ourselves of mercury.

No comments:

Post a Comment