Here in DC another school was closed while a Mercury spill was cleaned up. Apparently a thermometer broke.
When I was in elementary school in teh '70s I remember a classmate bringing in a vial of Mercury that her dad had given her. We rolled it around on the floor at recess and had great fun. As far as I can tell there were no negative results. Similar things happened later in high school.
So what’s the deal? Were we in great peril back in the day, or is there a bit of irrational fear today?
Stickly my own opinion but I think there’s an awful lot of hysteria involved. We did the same thing in school as you because mercury is such fun to play with. I have also told here about my college chemistry experience with a big blue splotch on the palm of my hand from mercuric oxide poisoning.
Exposure to mercury over a long period of time is no doubt dangerous and maybe in the case of an elementary school they were worried about children ingesting it but it sure seems like an over reaction to me.
In fact, come to think of it, it’s probably a Cover Your Ass maneuver to forestall any possible legal problems.
Some of Column A, some of Column B.
Yes, mercury is toxic stuff. Yes, we probably were putting ourselves at some risk by playing with it in our hands. But to close an entire school because someone dropped a thermometer? Do they also plan to evacuate the neighborhood if the custodian drops a fluorescent tube when changing one?
If they were planning on such an extreme response, why didn’t they get rid of all the mercury thermometers earlier? And, when can we expect schools to start replacing those horribly dangerous mercury vapor-filled fluorescent lamps with incandescant light bulbs?
I fear this is yet another example of “zero tolerance” taken too far.
The main problem is that you might leave some lying about. Brief exposure like you describe won’t really be a problem, but “loose” mercury has the nasty habit of rolling into a crack someplace and staying there. It vaporizes, and becomes a source of long-term mercury exposure to people who are in the room every day.
Heavy metals like mercury are accumulative poisons that the body doesn’t rid itself of easily. You can slowly build up enough of a dose to do you harm by being exposed to very small amounts every day. This factor probably justifies worry about seemingly small amounts of the stuff in the environment.
That said, closing a school because of a broken thermometer is probably overkill, and a sign of our litigous society. Some responsible person should be able to handle making sure they picked it all up, and maybe sprinkling some sulphur on the area for a few hours. But if they aren’t “qualified”, the school is risking a lawsuit, so in comes the hazmat team.
Mercury, the liquid metal, is not dangerous, unless you happen to be crazy enough to drink some (and for all I know may not even be a problem then).
But mercury is slightly volatile, and mercury vapor is a mild toxin, which as yabob notes is an accumulative poison. Trust me on this; I lost my mother to interstitial fibrosis brought on by 30+ years doing quality control in a mercury-thermometer manufactory.
As noted, it’s probably overkill to evacuate more than the room the thermometer broke in, and a simple cleanup would probably be sufficient. Fear of lawsuits is, as noted, probably behind it.
But this is a case where intelligent caution is indicated – it’s neither a catastrophic disaster nor a “Chicken Little” situation.
IMHO the dangers of mercury spills are somewhat underestimated in this thread.
However, the follwing two links suggest, that the U.S. regulations about hazardous materials require to call a hazmat team in order to handle a mercury spill:
http://www.jtbaker.com/msds/englishhtml/m1599.htm
http://environmentalchemistry.com/yogi/hazmat/erg/gn/172.html
cu
One more site with very detailed toxicology information on mercury:
http://www.atsdr.cdc.gov/toxprofiles/tp46.html
Cite from this site: "How does mercury affect children?
Very young children are more sensitive to mercury than adults. <snip> Children poisoned by mercury may develop problems of their nervous and digestive systems, and kidney damage."
This also suggest to be very careful about mercury spills in schools.
cu
little hijack …
I was working on a computer in an elementary school when a rather large black widow ran from under and scooted behind a table. I happen to loathe those things and went to get a spider spray. But there is none. I was told that, before you spray that spider, you have to send written, 2day notice to all the parents.
I’m not licensed, so I couldn’t use the spray, anyway. I have permission to stomp on her, but I couldn’t see her or get to where she is with a stick. She’s still there.
I wonder how big they get?
Oh, just dump some flowers of sulfur on it, let it sit for a while and then clean it up. Properly dispose of the waste and stop whining. As my mother said, when she worked in a hospital back in the day, it was SOP. And lightbulbs have as much mercury in them, if I’m not mistaken. Lots of schools have gotten rid of their mercury thermometers, I know, as I think they gave them all to our lab.
I have been flabbergasted by the local news reports on these two DC schools in the past week or so. It is dangerous, but only with prolonged or extreme (as in swallowing) exposure. Years of constant use will do it. Lewis Carroll’s Mad Hatter in Alice in Wonderland is a (parodied) example of the actual problems faced by haberdashers from mercury poisoning. More sobering, Polycarp’s mother is an unfortunate further example of constant exposure over an extended period of time.
Breaking a thermometer in class? It’s overreacting, pure and simple. The floor gets cleaned and waxed that night, the kids get their clothes washed and a quick shower in the evening, everything’s fine. There was a time that kids did poke and prod mercury with their bare hands in Chemistry class, and they seemed to live and grow up to be the overreacting school officials today.
You weaken your own case with that final underscored statement. Clearly there was some significant cognitive damage! 
Well, when I started that post, there was a word of thanks between the two halves of quote! :o
But one should leave room for doubt that it was not the mercury to stunt their minds. Og only knows to what other chemical substances they were exposed in college. 
The don’t get very big but they produce hundreds of little black widows. Fortunately, when the eggs hatch and the case ruptures the little spiders, white by the way, come out they are close together and hungry so mostly they eat each other leaving only a few survivors.
Even it one stings you, you might not die.
Yeah sure. Was it not in the U.S. in the 1950s that the government educated children to duck and hide in case of a nuclear war? Well if this works, then surely you do not need to worry about a little bit of mercury.
I have to go now, before I am getting too cynical.
cu
The amount of mercury in lamps is way down from the good old days:
National Electrical Manufacturer’s Association on Mercury in lamps