B
bz
- Jan 1, 1970
- 0
I too remember playing with mercury obtained from various sources, coating
a penny with it, and the oily feel of the coated penny.
Metallic mercury is hazardous under three circumstances: 1) when heated.
2) when a small amount of mercury is exposed to the air in the room where
you work regularly. 3) When water soluble form is present in food or
drink.
Mercury builds up in the body over time because the elimination of mercury
is very slow.
So, if you heat mercury, its high vapor pressure puts a lot of mercury
vapor into the air and you can absorb a fatal dose very quickly. If you
work in a room where mercury has been spilled, its room temperature vapor
pressure is sufficient for you to, over time, build up enough mercury to
experience toxic effects.
"The Handbook of Laboratory Safety" (CRC) has an interesting chapter on
mercury.
When I was studying chemistry in college, we had an almost fatal accident.
A student was working alone in a lab [never work alone!]. Another
student had left, leaving a beaker of Mercuric Chloride solution heating.
The water evaporated and the mercuric chloride decomposed, giving off
mercury vapor.
The student that had been working alone in the room was found, crawling out
of the lab. They got him to the hospital and started treating him
immediately for mercury poisoning.
He spent about a week in the hospital, with special chemicals being
dripped into his veins to remove the mercury from his body. He said that
the treatment felt like liquid fire being pumped into his veins. During
that time, he wished he were dead.
His first urine sample, taken after admission, had enough mercury in it
to KILL ten people.
Of course, water soluble mercury and lead compounds are much more
dangerous than metallic mercury or metallic lead as they are easier to get
into the human body.
Normal 'clearance' of mercury is on the order of a maximum of 2 mg per
day. So if you are absorbing more than that, you are building up toward a
toxic dose.
Of course, children are more sensitive to the toxic effects of heavy
metals.
--
bz
please pardon my infinite ignorance, the set-of-things-I-do-not-know is an
infinite set.
[email protected] remove ch100-5 to avoid spam trap
